VoltIC pro I is the perfect combination of voltammetry and ion chromatography for the fully automated analysis of anions, cations, and heavy metals (e.g., Zn, Cd, Pb, Cu): comprehensive water analysis on a single system.

This Process Application Note details the simultaneous online analysis of H2S and NH3 in sour water which was previously treated in the sour water stripper (SWS). The method includes automatic cleaning and calibration. Fast and accurate results are continuously supplied for process control.

Acrylic acid dimerizes spontaneously. Determining the dimer content is, therefore, a key part of the quality control for acrylic acid. One quality control parameter for the dimerization is the acid number. This Application Note describes its determination by automated, potentiometric titration.

This Process Application Note describes a method to determine the strontium and barium concentration in brine as early detectors ofmembrane fouling via online process ion chromatography. Using this multiparameter analytical technique can help reduce the risk of premature membrane fouling and avoid unexpected maintenance and high utility costs with 24/7 automated analysis.

This White Paper compares automated Inline Ultrafiltration and Inline Dialysis to the traditional Carrez clarification procedure for the analysis of milk samples by ion chromatography (IC). A continuous test series over approximately six months proved Inline Dialysis to be a reliable and valuable alternative to treat dairy products prior to IC analysis.

The TitrIC flex II system is the perfect combination of titration, direct measurement, and ion chromatography for fully automated analysis of all key parameters. These include pH, conductivity, hardness, anions, cations, as well as the calculation of the ion balance: comprehensive water analysis from one system.

The automated combination of pyrolysis and subsequent ion chromatography (Combustion IC) permits the parallel detection of halogens and sulfur in all flammable solid and liquid matrices. The method is captivating, not only because of its outstanding precision and trueness, but also because of the high sample throughput.

Identification of unknown materials in the field can be a complicated affair, especially in critical situations, where speed, safety, and ease-of-operation are essential. Mira DS, Metrohm Raman’s handheld Raman analyzer, and the intelligent Universal Attachment (iUA) give the user automated Content ID capabilities. Content ID achieves through container identification of unknown materials quickly, easily, and safely.

ASTM D8192 describes the photometric titration of the total hardness, calcium hardness, and magnesium hardness in water with an optical sensor for objective endpoint indication, increasing precision and reliability. The method is suitable for both colored and colorless samples such as groundwater, surface water, wastewater, and drinking water. Using a fully automated OMNIS system equipped with an Optrode ensures that the sample preparation and analysis are repeatable.

The water content of lyophilisates contained in vials is determined by Karl Fischer titration. Conditioned solvent (methanol) is injected into the vial to dissolve the sample and extract the water (ultrasonic bath). Afterwards the contents of the vial are transferred to the titration vessel to carry out the automatic determination.

VoltIC Professional 1 is the perfect combination of voltammetry and ion chromatography for the fully automated, simultaneous analysis of anions, cations, and heavy metals (e.g., Zn, Cd, Pb, Cu). The multiple-parameter analysis uses the same "Liquid Handling" elements and a shared sample changer, thus saving on space and costs.

Determination of the total sodium content of sodium aluminate liquors, such as Bayer Process liquor. This method is suitable for the analysis of all sodium aluminate solutions down to at least 1 g/L as Na2CO3. The determination may be automated by adding an 814 USB sample processor to an 859 Titrotherm.

A setup that allows online sampling is crucial for immediate and contamination-free analysis of power plant water samples. This application recommends a setup that facilitates simultaneous anion/cation determinations. Automated inline sample preparation combines variable preconcentration (MiPCT) and calibration with a single multi-ion standard. AN-Q-005 shows the respective anion results.

A setup that allows online sampling is crucial for immediate and contamination-free analysis of power plant water samples. This application recommends a setup that facilitates simultaneous anion/cation determinations. Automated inline sample preparation combines variable preconcentration (MiPCT) and calibration with a single multi-ion standard. AN-Q-004 displays the respective cation results.

The basicity and the CPR (controlled polymerization rate) are very important parameters for the quality of polyols used in polyurethane production. The knowledge of these values is crucial to prevent gelation during handling in the production. In this Application Note their determination by automated, potentiometric titration according to ISO 14899 is described.

The Application Bulletin describes the determination of suppressor in acid copper baths by smartDT. The determination of suppressor with dilution titration (DT) involves numerous additions with standard solution or sample to reach the evaluation ratio. Usually fixed, equidistant addition volumes are used. With smartDT, variable addition volumes are used that are dynamically calculated by the software. At the beginning, the volumes are bigger. Towards the evaluation ratio, the addition volume becomes smaller to guarantee a good accuracy of the result. The operator defines the first and the smallest addition volume to be used. All volumes in between are calculated by the software considering the progress of the determination. The time saving with smartDT compared to a classic DT with fixed addition volumes can be up to 40%. smartDT is suitable for nonlinear regression and quadratic regression as well as linear interpolation. It can be used for determination of suppressor in acid copper baths as well as in tin and tin-lead baths and works with 1, 2, and 3 mm Pt working electrodes. A 800 Dosino is required for the automatic addition of suppressor standard or sample. The method can also be used in fully automated systems.

Methods are described for the potentiometric analysis of the following bath components:Brass plating bath: copper, zinc, free cyanide, ammonium, carbonate, and sulfite.Bronze plating bath: copper, tin, and free cyanide.

Sodium fluoride tablets for pharmaceutical use need to comply with U.S. Pharmacopeia (USP) requirements. Ion chromatography (IC) with suppressed conductivity detection has been approved by the USP as a validated method to quantify fluoride content in sodium fluoride tablets. In the course of the USP monograph modernization, using automated IC makes this type of analysis even easier.

The total acid number (TAN) indicates the amount of potassium hydroxide required for neutralizing all carboxyl-terminated groups and free acids plus the free anhydride groups in an unsaturated polyester resin (UPR). In this Application Note the TAN determination using automated, potentiometric titration according to EN ISO 2114 using KOH in ethanol as titrant is described.

The iodine adsorption number (IAN) of carbon black is related to the surface area and can therefore be used for the characterization of carbon black. The presence of volatiles, surface porosity, or extractables will influence the iodine adsorption number. In this Application Note, the fully automated determination of the iodine adsorption number including sample preparation is described.

The EU directive for limiting the use of certain hazardous substances in electrical and electronic devices and IEC 61249-2-21 define limit values for halogen contents in materials that are used in electronics. Metrohm Combustion IC with ion chromatography determination permits precise, rapid and automated halogen determination in raw materials that are used in printed circuit boards according to IEC 61189-2.Keyword: pyrohydrolysis

Anion analysis in milk requires a sophisticated sample preparation to avoid column fouling by fats or proteins. Here Metrohm Inline Dialysis is the perfect automated technique. In dairy products iodide, thiocyanate, and perchlorate need to be determined regularly for health and hygiene reasons. This application allows for the first time to analyze these three components in this matrix within one run.

The partial acid number (also partial acid value) describes the quantity of potassium hydroxide that is required for neutralizing all carboxyl-terminated groups and free acids plus half the anhydride groups in an unsaturated polyesterresin (UPR). This Application Note describes the determination of the partial acid value by automatic, potentiometric titration according to EN ISO 2114 using KOH in ethanol as titrant.

The hydroxyl number indicates the amount of potassium hydroxide in milligrams required to neutralize the acetic acid taken up on acetylation of 1 g of an unsaturated polyester resin (UPR) containing free hydroxyl groups. In this Application Note the determination of the hydroxyl number by automated, potentiometric titration according to EN ISO 2554 using KOH in methanol as titrant is described.

Metrohm Raman presents a unique handheld materials identification system designed to meet the needs of defense and security professionals. Meet Mira DS, the most adaptable Raman analyzer available today. Mira DS was developed directly in response to requests from first responders in the field for a small, rugged, automated materialsidentification system that ensures the safety of the user in any situation.

This poster presented jointly with USP at AAPS meeting shows the new USP method for zinc as per <591> using Ion Chromatography which is highly selective and sensitive. Selectivity is achieved by separation and further improved with PCR reaction. Sensitivity and wide linear quantification limit make the new USP method ideal for QA/QC. Automated PCR delivery makes the overall method performance easy to validate.

Tafel analysis is an important electrochemical technique used to understand reaction kinetics. By studying the Tafel slope, it reveals the rate-determining steps in electrode reactions, aiding fields like corrosion and fuel cell research. This method helps industries optimize processes and improve device performance by tailoring materials and conditions for greater efficiency.

The lithium-ion battery market is continuously growing due to the tremendous demand for battery powered consumer products. So-called «NCMs», a mixture of nickel, cobalt, and manganese oxides, have been gathering interest as cathode materials, replacing traditional compounds like cobalt oxides.Quality analysis of the post-sintered materials or recycled batteries can be performed by titration, as demonstrated in this Application Note. A fully automated analysis of the corresponding metals can be performed with OMNIS and its pipetting equipment.

Electrochemistry, spectroscopy, and spectroelectrochemistry (SEC) are widely used techniques in many fields. However, the data curves obtained from these analyses are quite varied, and not all electrochemical peaks and spectroscopic bands can be measured with the same procedures. This Application Note examines four tools included in the DropView 8400 and DropView SPELEC softwares to facilitate the measurement and analysis of the collected curves and data. The following measurement options are explained in detail: automeasurement, set on curve measurement, set free measurement, and set step measurement.

Ion chromatography (IC) provides an automated, fast, and sensitive solution to accurately quantify cationic and anionic components including acetate simultaneously. This comprehensive approach makes IC an economic alternative to traditional techniques for the quality control of pharmaceutical solutions like haemodialysis concentrates. Ease-of use, accuracy, and the high-throughput of IC increase productivity and comply with the demands of modern routine and research labs.

Ion chromatography tackles difficult separation problems of various ionic species and typically works with conductivity detection. Mass detection as a secondary independent detector significantly lowers the detection limits and confirms the identity of analytes even when coeluting. This poster describes how the combination of IC-MS and automated sample preparation techniques cope with the analysis of anions and oxoanions in challenging matrices such as soil or explosion residues.

Eluent preparation on demand (EPOD) is the convenient and flexible way of automatic eluent preparation. The 849 Level Control together with an 800 Dosino equipped with a 50 mL dosing unit are used to dilute an eluent concentrate to the required eluent concentration. The use of eluent concentrates is suitable for any eluent. This facilitates unattended operation of the system over several weeks (see AN S-296 for anion eluent preparation).

Sample dilution is a work-intensive routine task in the analysis laboratory. An automatic two-step dilution exponentiates the dilution factor – 1:100 – thus incorporating a dilution factor of 10,000. The intelligent dilution is made possible by MagIC Net, which calculates the essential dilution steps, and by the dosing properties of the 800 Dosino and the Liquid Handling Station. The Application Note shows statistical results of a 1:10,000 dilution.

Chromate (Cr(VI)) is considered toxic and potentially carcinogenic, which is why its concentrations in children's toys should be kept as low as possible. The EU directive 2009/48/EC defines limit values for the migration of chromate from children's toys. The hydrochloric-acid-containing migration solution is diluted with a buffer. 2000 μL of this solution are injected automatically using intelligent preconcentration technology and matrix elimination. Detection takes place via ICP/MS.

Basic chemicals are added to petroleum products to prevent corrosion as they neutralize acidic components that form during the use and aging of these products. The base number (BN) gives an indication regarding the amount of these basic additives present, and it can be used as a measure for the degradation of the petroleum product.This Application Note describes the potentiometric determination of the base number according to ISO 3771, ASTM D2896, and IP 276 using the Metrohm Solvotrode easyClean and a fully automated OMNIS system.

This study compares air sampling data obtained by a filter-based method including off-line manual filter extraction followed by ion chromatographic analysis with those gained by an automated Particle-Into-Liquid-Sampler coupled to an ion chromatograph (PILS-IC).PILS-IC is a straightforward instrument for aerosol sampling that provides near real-time measurements for long-term unattended operation and is thus an indispensable tool to monitor rapid changes in aerosol particle ionic composition.

With the advent of electric automobiles, the demand for lithium batteries and with it the demand for lithium material will increase sharply. Brine lakes and hard silicate minerals are numbered among the most important sources of lithium. This Application Note addresses cation determination in seepage water from lithium minerals. Alkali and earth alkali metals are separated in the lithium digestions on the Metrosep C Supp 1 - 250/4.0 column, with subsequent conductivity detection after sequential suppression.

A combination of the 850 Professional IC and the 872 Extension Module Liquid Handling opens the field of Metrohm’s online monitoring by IC. In this application, Inline Preconcentration is coupled to Matrix Elimination (MiPCT-ME). By removing excess matrix components, corrosive anions can be sensitively determined. Additionally, this technique allows automated calibration using a single multi-ion standard solution. Online trace analysis for chloride and sulfate is possible for several different sample lines.

Eluent preparation on demand (EPOD) is the convenient and flexible way of automatic eluent preparation. The 849 Level Control together with an 800 Dosino equipped with a 50 mL dosing unit are used to dilute an eluent concentrate to the final eluent concentration. The use of eluent concentrates is suitable for any type of eluent. This facilitates unattended operation of the system over several weeks (see AN C-134 for cation eluent preparation).

Titrants are normally bought ready to use. However, it is necessary to determine the accurate concentration of your titrant solution on a regular basis using a primary standard. To correct the mentioned variation, a so-called «titer factor» is applied. The titer can be easily and quickly assessed by using the Metrohm brand of autotitrators. Predefined calculation formulas implemented in Metrohm titrators or software, respectively, as well as the automatic storage of the titer factor, makes standardization a simple task.

This Application Bulletin describes the determination of the thermostability of PVC in accordance with ISO 182 Part 3 using the dehydrochlorination method with the 895 Professional PVC Thermomat. The instrument permits fully automatic determination of the stability time. The test is suitable for monitoring the manufacture and processing of PVC products manufactured in the injection molding process, for their final clearance, characterization and for the comparison of PVC products and for testing the effectiveness of heat stabilizers.

Inline Ultrafiltration is a proven sample preparation technique for samples that are slightly or massively contaminated with particles, algae or bacteria. Filtration and injection are coupled and fully automatic. As a rule, 100 or more samples can be filtered through a single membrane. Service life is extended – even with highly contaminated tannery effluent – to more than 300 injections because the filter membrane is rinsed again once more after the analysis with the aid of the Dosino backflush.

EN ISO 10304-1 is one of the most important standards for the determination of the seven standard anions in water samples. Many other standards refer to EN ISO 10304-01 if anion determination by IC is required. This standard asks for a membrane filtration for samples to avoid bacteria and solids, if required. This application shows the determination of anions according EN ISO 10304-1 applying Inline Ultrafiltration. This setup avoids tedious manual sample filtration and handles any samples fully automatically.

OpenLab CDS is the newest generation of the Agilent chromatography data systems platform. The Metrohm IC Driver 1.0 for OpenLab CDS enables introducing Metrohm IC instruments to this platform for full control and data acquisition. This application shows the analysis of iodide by amperometric detection, enabling detection at trace levels. The eluent is produced automatically by the 941 Eluent Production Module. In this way, amperometric detection can be executed with the same functionality and performance as with MagIC Net.

The combination of 850 Professional IC, 858 Professional Sample Processor, Dosino and MagIC NetTM software offers a variety of automated ion chromatographic sample preparation and calibration techniques available as an anion, cation or dual channel system. Calibration is straightforward and requires only one multi-ion standard.Inline calibration allows the calibration of any standard concentration in the ppt range by using one single stable standard solution at the ppb level. By using a preconcentration column and switching the valves one, two or more times different calibration concentrations at the ultra-trace level can be created with unprecedented reproducibility. The inline preconcentration technique uses a pre-concentration column and is ideally suited for trace analysis in complex matrices, especially when combined with matrix elimination. Besides facilitating the preparation of g/L to ng/L calibration graphs Metrohm`s intelligent techniques are capable of logical decision making. While Metrohm`s intelligent Partial Loop technique (MiPT) allows samples with a wide concentration range to be injected without previous manual dilution, the intelligent inline dilution technique, after the first sample injection, compares peak areas, calculates, if necessary, the dilution factor, dilutes and automatically re-injects the sample. The presented inline techniques allow the rationalization of the time-consuming, error-prone and cost-intensive manual preparation of standard solutions. They guarantee that the determined sample concentrations always lie within the calibration range. Higher sample throughputs as well as lower analysis costs and improved data reliability are achieved.

The determination of the total causticizer, sodium carbonate and aluminum oxide contents in (Bayer) process liquors can be accomplished with high precision and speed by using the 859 Titrotherm in a thermometric acid-base titration. A complete titration takes approximately 5 minutes.The procedure is an automated adaptation of the traditional Watts-Utley method, and is similar to the VanDalen-Ward thermometric titration method, but with the added advantage that the analysis can also be performed for the carbonate content of the liquor.

For titrations in low conducting media (e.g., non-aqueous titrations) the potentiometric indication can be disturbed by interfering signals. When differential amplification is used, these signals are measured by both the measuring electrode and the reference electrode and thus neutralized. It is therefore possible to obtain smoother titration curves and more reproducible results.This Application Note describes the potentiometric determination of the acid number and base number in used motor oil by the differential amplification using a fully automated OMNIS system.

Lithium carbonate is a key cathode material for lithium-ion batteries, and accurate carbonate content determination is essential for assessing purity and ensuring consistent battery performance, stability, and safety. This Application Note describes the automated determination of carbonate in lithium carbonate using the OMNIS Titrator and OMNIS Sample Robot with Dis-Cover lids according to the draft ISO 10662 standard. The OMNIS system provides fast, reliable purity analysis and can be readily expanded to support additional titration applications.

Lithium nitrate is an oxidizing agent used in the manufacture of red-colored fireworks and flares. In addition, the lithium nitrate trihydrate compound absorbs heat well and can be used for thermal energy storage. Since lithium nitrate is a hygroscopic substance, its purity must first be verified before it is used for synthesis or other applications. The purity assay is done by a fully automated precipitation titration between lithium and fluoride in an ethanolic solution. The benefit of titration is that the lithium nitrate does not need to be diluted after dissolving in ethanol as with other techniques such as ICP-MS.

Cellulose ester foils are produced using chlorinated solvents. The residual amount of the solvent used in production evaporates within a few days in ambient conditions. The residual solvent is determined by combustion IC, through the conversion of organically bound chlorine to chloride by pyrohydrolysis. The final product needs to be free of all chlorinated solvents. Therefore, critical contents of such compounds can be detected in quality control analysis. Application of MiPT in this study has enabled an automated and precise calibration out of a single standard.

Due to its price and wide availability, the anionic surfactant sodium lauryl sulfate (SLS; SDS) can be found in many detergents as an emulsifier or as a fat solvent e.g., in cleaning or cosmetic products. To avoid causing severe dry skin and hair, and thus skin irritation, regulations in many countries have restricted the sodium lauryl sulfate concentration in ready-to-use products to a range between 0.05–2.5% SLS. To control the concentration of SLS in different products, a titration is carried out with TEGO® trant A100 and the Optrode. The evaluation is done automatically by means of a software, leading to reliable and reproducible results.

The bromine number indicates the degree of unsaturation and relies on the simple addition of bromine to the double bonds of alkenes. One mole of bromine is consumed for each mole of carbon-carbon double (C=C) bond present in a substance. In petroleum products, the bromine number corresponds to the olefin content.Normally, chlorinated solvents are used for the determination of the bromine number. In this Application Note they have been replaced by toluene. This makes the determination more ecological. The titration is performed automatically on an OMNIS system in combination with a double Pt-wire electrode. With this setup, a fast and accurate determination by potentiometric titration can be realized.

Measures to monitor or prevent corrosion are crucial in nuclear power plants, where significant risks to health and safety can occur if corrosion is left unchecked. Anions corrode metals under high temperature and pressure, therefore their concentrations must be monitored at all times. The analytical challenge in the primary circuit is detection of anions in the μg/L range alongside gram quantities of boric acid and lithium hydroxide. Precise, reliable trace analysis requires the method to be automated as much as possible. The 2060 IC Process Analyzer from Metrohm Process Analytics can measure several anions from a single injection, with combined Inline Preconcentration and Inline Matrix Elimination to measure low anion concentrations precisely and reliably time after time.

Material verification models with complex algorithms such as Principal Component Analysis (PCA), quasi-infinite parameters, and preprocessing options can be incredibly complex. Each model must be rigorously built, evaluated, and validated before it can be put into routine use. Mira P simplifies material verification for all. With a short, defined user workflow, straightforward results, and a foolproof Operating Procedure-based design, Mira P is already one of the simplest RMID tools available. ModelExpert, in Mira Cal P, does a chemometrician’s work. ModelExpert automatically determines the best model parameters for robust method development. With Mira P and ModelExpert, even non-technical users can achieve better results in a fraction of the time.

The metals Cd, Co, Cu, Fe, Ni, Pb, and Zn are determined in the sub-ppb range (limit of detection 0.05 µg/L) by means of stripping voltammetry. The DP-ASV method is used for Cd, Cu, Pb, and Zn whereas Co, Ni, and Fe are determined by means of the DP-CSV method (dimethylglyoxime or catechol complexes).Use of the VA Processor and the sample changer allows automatic determination of the above metal ions in one solution. The method has been specially developed for trace analysis in the manufacture of semiconductor chips based on silicon. It can naturally also be employed successfully in environmental analysis.

The commercialization of Li-ion batteries in 1991 was the culmination of in-depth R&D conducted by scientists and engineers around the globe over the preceding few decades. Further development of Li-ion batteries and alternative rechargeable batteries has continued until today. As the world is rapidly moving towards a new era defined by green technologies, more practical and accurate R&D is required in order to meet the increasing demands for energy storage systems, specifically from the automotive industry. This white paper presents the basics of the Li-ion battery technology and guides the reader through the relevant techniques and terminologies in Li-ion battery research.

Corrosion of metallic components is an inherent problem for engines, because metals naturally tend to oxidize in the presence of water and/or low pH value. The reserve alkalinity of engine coolants and antirusts is a measure of the buffering ability to absorb acidity. The reserve alkalinity is frequently used for quality control during production and often listed in the specifications of the coolants. A fast and accurate determination is therefore important.This Application Note describes the straightforward determination of reserve alkalinity according to ASTM D1121. Using a fully automated system allows an accurate and reliable determination due to the reduction of human errors. Furthermore, the operator is free to carry out other tasks increasing the efficiency of the laboratory.

Moisture in petroleum products causes several issues: corrosion and wear in pipelines and storage tanks, an increase in debris load resulting in diminished lubrication, blocked filters, or even harmful bacterial growth. As a result, increased water content can lead to infrastructure damage, higher maintenance costs, or even unwanted downtimes.Coulometric Karl Fischer titration is the method of choice for low water content in petroleum products. Using a Karl Fischer oven to vaporize the water present in the sample prior to titration not only greatly reduces matrix interferences, it can also be fully automated. This allows a reliable and cost-efficient analysis of the water content according to ASTM D6304 (Procedure B) in products such as diesel, hydraulic oil, lubricant, additive, turbine oil, and base oil.

Neutralizing amines are added to adjust pH levels within the water-steam circuit of power plants to avoid corrosion-inducing conditions. This preventive maintenance can reduce costly and critical downtimes due to corrosion, however frequent monitoring of the amine chemistry is necessary to ensure conditions stay optimal. The 2060 IC Process Analyzer featuring the Metrohm intelligent Partial Loop Technique (MiPT) option is ideal for this application, with the ability to measure trace amounts of the analytes precisely and reliably through an automated method. The benefit of using IC is that multiple analytes can be monitored simultaneously, and here the ability to measure the presence of sodium next to the high ammonium or amine concentrations could indicate that cooling water is seeping into the circuit, indicating a problem upstream.

In order to maintain product quality, the sodium chloride content in dairy products must be monitored and not exceed the limits defined by the respective public health authorities. The chloride content in food correlates with the salt content, its determination is therefore described in various norms and standards. However, preparation of such samples is time consuming, as it includes a chloride extraction with warm water. Whole milk powders in particular are difficult to handle as an inhomogeneous dispersion of fat in the titration suspension occurs.In order to reduce the workload, increase sample throughput, and eliminate the matrix challenges posed by high fat products, this Application Note presents a fully automatic potentiometric titration of chloride with silver nitrate in milk and milk powder based on ISO 21422, IDF 242, AOAC 2015.07, AOAC 2015.08 and AOAC 2016.03

In power plants, corrosion is the primary factor leading to costly and critical downtimes. In a nuclear power plant, a separate water circuit known as the Pressurized Water Reactor (PWR) ensures radioactive material stays contained while still transferring heat and energy to the other circuits. Boric acid and lithium hydroxide are added specially to the PWR circuit in amounts which can complicate other analytical measurements. Lithium prevents corrosion and must be monitored, along with other cations such as zinc, nickel, and ammonium. In order to measure these cations online at sub-µg/L range in a single analysis, the 2060 IC Process Analyzer is offered with combined Inline Preconcentration and Inline Matrix Elimination. Several cations can be analyzed in a single injection, with automated sample preparation making precise and reliable measurements easier.

Lithium salts (e.g., lithium carbonate and lithium hydroxide) are used in myriad applications. Lithium hydroxide is used for the production of lithium stearate, an important engine lubricant. In addition, it is utilized as an air purifier due to its ability to bind carbon dioxide. While the majority of lithium carbonate is used for aluminum production, it is also used for the glass and ceramic industry. It lowers the melting point of these materials, lowering the associated electricity costs and making it cheaper to produce them.For all of these applications, it is important to know the quality of the pure lithium salts used in the various production processes. This Application Note presents an easy method for the assay of lithium hydroxide and lithium carbonate on an automated OMNIS system.

UV/VIS detection is one of the most sensitive detection techniques in trace-level chromatography. Sometimes, however, spectrophotometric detection lacks sensitivity, selectivity or reproducibility and chemical derivatizations are required. By using Metrohm`s rugged and versatile flow-through reactor, single- or multi-step derivatizations can be done fully automatically, in either pre- or post-column mode at any temperature between 25…120 °C. The variable reactor geometry allows to adjust the reactor residence time of the reactants according to derivatization kinetics. The flexibility of the reactor is demonstrated by optimizing four widespread post-column techniques: the relatively slow ninhydrin reaction with amino acids and the fast derivatizations of silicate, bromate and chromate(VI).

Sulfite is found in many drinks, dried fruit, snacks etc. It acts as a preservative and may be added artificially or can be a side product of fermentation. As sulfite can induce a health risk, it is banned in raw foods and must be labeled on processed foods. Analysis of sulfite by IC with DC amperometric detection is nearly impossible due to the food matrix which fouls and deactivates the electrode surface very fast. The new automatic CV activation procedure (CV treatment, patent pending) cleans the electrode surface and recovers its sensitivity. This report shows DC amperometric detection of sulfite in several foodstuffs applying this activation step prior to the sulfite detection.

Nitrate is present in all common agricultural products and due to an extensive use of fertilizers, the nitrate content can be disconcertingly high in vegetables and their fabricated products, like juices. The nitrate content is regulated in many countries because it can form nitrosamines within the human body. Nitrosamines can potentially cause cancer and therefore, the World Health Organization (WHO) has defined an accepted daily intake (ADI) for nitrate of 3.7 mg/kg. To control the nitrate content e.g., in juices, a quick and inexpensive assessment of its concentration is performed via standard addition with a nitrate ion selective electrode . The method can be automated and is faster and less expensive compared to competing chromatographic or spectroscopic methods.

Electroplating processes are used in several different industry sectors to protect the surface quality of various products against corrosion or abrasion and significantly improve their working life. It is essential to check the bath composition on a regular basis to ensure that the process is operating correctly. Typical examples of electroplating baths include alkaline degreasing baths or acidic or alkaline baths containing metals e.g. copper, nickel, or chromium, or components like chloride and cyanide. It is crucial that the chosen analysis technique fulfills high safety standards for these kinds of analyses and produces reliable results. The OMNIS Sample Robot system automatically pipettes and analyzes aggressive electroplating bath samples on different workstations, increasing the safety in the lab. This provides more reliable results in comparison to manual titration and is more time efficient as different parameters can be analyzed in parallel.

Compared to the classical Epton titration, potentiometrically indicated two-phase titrations using organic-solvent-resistant Surfactrodes can be easily automated and require no toxic and environmentally hazardous chloroform. Even challenging matrices such as fats and oils in bath oils and hair conditioners or strong oxidizing agents in washing powder and industrial cleaners do not interfere with the titration of the ionic surfactants. Results obtained show excellent agreement to those of the Epton titration. Irrespective of the matrix, relative standard deviations of threefold determinations are all below 2.1%. While the Surfactrode Resistant is mainly used for oil-containing formulations, the Surfactrode Refill is ideal for washing powders and soaps. Both electrodes excel by their ruggedness and allow the rapid and precise determination of anionic and cationic surfactants.

The hydroxyl number (HN) is an important sum parameter for quantifying the presence of hydroxyl groups in chemicals. As a key quality parameter, it is determined in various substances. For pharmaceutical samples, USP chapter <401> and Ph. Eur. Chapter 2.5.3 describe the determination. However these methods either use toxic pyridine and require refluxing or have long reaction times.In this Application Note, an alternative method according to ASTM E1899 is presented. This method is pyridine-free and does not require refluxing or long reaction times. The determination is performed at room temperature with only a small sample size. The analysis including all preparation steps is performed with a fully automatic OMNIS system. This allows parallel analysis of multiple samples, increasing productivity in the laboratory by 50%.

In the food industry, it is essential to determine and monitor certain quality parameters to guarantee consistency. This is especially important for liquid dairy products, which are subject to a strict cold chain. Both the dissolved oxygen (DO) and the pH value have proven to be reliable quality criteria. Oxygen shortens the shelf life and influences the product quality (e.g., nutritional value, color, and flavor). The DO content depends on the salinity in the sample, which is automatically calculated and corrected by the 914 pH/DO/Conductometer during the parallel conductivity measurement. Acidity is another important characteristic to measure that can be checked easily using the pH value. With the 914 pH/DO/Conductometer, all important quality criteria can be monitored with one device.

The determination of suppressor with dilution titration (DT) involves numerous additions with standard solution or sample to reach the evaluation ratio. Usually fixed, equidistant addition volumes are used. With smartDT, variable addition volumes are used that are automatically calculated by the software. At the beginning, the volumes are bigger. Towards the evaluation ratio, the addition volume becomes smaller to guarantee a good accuracy of the result. The operator defines the first and the smallest addition volume to be used. All volumes in between are calculated by the software considering the progress of the determination. Using smartDT with intelligent addition volumes, the determination of suppressor can be significantly accelerated with the same or even better accuracy than with the classic DT. The time saving per determination is between 20 and 40%.

Iron sucrose injection is a dark brown liquid which contains sucrose and iron(III) hydroxide in an aqueous solution, commonly used for the treatment of iron deficiency anemia. As a medical product, iron sucrose is subject to strict controls. Among other tests, the U.S. Pharmacopeia (USP) requires to monitor the limit of Fe(II) in the iron sucrose injection solution by polarography. The benefit of polarography is that Fe(II) and Fe(III) show signals at different potentials, and therefore an easier determination of Fe(II) without a previous separation of the two oxidation states is possible. The 884 Professional VA together with the viva software allows a straightforward determination of the Fe(II) content of iron sucrose injection solution following the requirements of the USP. The Fe(II) content is automatically calculated and stored in a database together with all relevant determination and calculation parameters.

This document outlines complexometric and potentiometric determination of metal ions via EDTA titration using a copper-selective electrode (Cu-ISE) with a durable epoxy shaft and crystal membrane. Because the electrode is insensitive to complexing agents, a preformed Cu–metal complex must be introduced into the sample prior to analysis. The method, applicable to direct or back-titration, exploits EDTA–metal formation constants to define equivalence points and enables quantification in several different matrices.

Ion chromatography mass spectrometry (IC-MS) is a powerful tool that can handle many challenging analytical tasks which cannot be performed adequately by IC alone. IC-MS is a robust, sensitive, and selective technique used for the determination of polar contaminants like inorganic anions, organic acids, haloacetic acids, oxyhalides, or alkali and alkaline earth metals. After separation of the sample components via IC, mass selective detection guarantees peak identity with low detection limits. The inclusion of automated Metrohm Inline Sample Preparation (MISP) allows not only water samples, but also chemicals, organic solvents, or post-explosion residues to be readily analyzed without need for extensive manual laboratory work. This White Paper explains the benefits of IC-MS over IC in certain cases, the hyphenation of IC and different MS systems, as well as related norms and standards.

Beer is a popular beverage consumed by millions of people for enjoyment, despite its humble beginnings as a water purification technique in pre-modern times. Brewing beer requires large amounts of water which must adhere to strict alkalinity, hardness, and pH parameters to ensure uniformity in flavor and appearance between each batch. Alkalinity is introduced by carbonates and hydroxides in water which raise and buffer the pH. Hardness, balanced to a large degree by the alkalinity, comes from Ca and Mg ions, mainly present as hydrogen carbonates. Depending on the concentration ranges, the 2035 Process Analyzer or the 2060 Process Analyzer are ideally suited for the fully automatic execution of these important analyses, as well as additional parameters like pH or conductivity. These process analyzers can signal the plant’s distribution system to correct the water chemistry, ensuring consistent product quality. In addition to alkalinity and water hardness, numerous other parameters can also be determined (pH, conductivity, etc.).

As the determination of the exact content of individual glycerides in fats and oils is difficult and time-consuming, several fat sum parameters or fat indices are used for the characterization and quality control of fats and oils. Fats and oils are not only essential for cooking, they are also an important ingredient in pharmaceuticals and personal care products, such as ointments and creams. Consequently, several norms and standards describe the determination of the most important quality control parameters. This Application Bulletin describes eight important analytical methods for the following fat parameters in edible oils and fats:Determination of water content in accordance with the Karl Fischer method; Oxidation stability in accordance with the Rancimat method; Iodine value; Peroxide value; Saponification value; Acid value, free fatty acids (FFA); Hydroxyl number; Traces of nickel using polarography; Special care is taken to avoid chlorinated solvents in these methods. Also, as many of the mentioned methods as possible are automated.

Sulfites are well-known additives in foods and beverages used to extend shelf life and preserve colors. Such properties have led to the broad usage of sulfites in a range of foodstuffs like fruits, cereals, vegetables, seafood, juices, alcoholic and non-alcoholic (soft) beverages, and in some meat products. The term «sulfites» describes a group of molecules that include sulfur dioxide (SO2) and chemically related molecules like sodium sulfite (Na2SO3), sodium bisulfite (NaHSO3), or sodium metabisulfite (Na2S2O5). Sulfite intake has been correlated with several adverse reactions, and therefore sulfites are included in the FAO/WHO Codex Alimentarius list. Labelling sulfite content in foods and beverages is necessary when the total concentration exceeds 10 mg/kg. Metrohm ion chromatography allows the reliable measurement of sulfite in different matrices using either conductivity or amperometric detection. The inclusion of automated sample preparation and cleaning steps with Metrohm instrumentation saves additional analyst time and helps increase sample throughput.

The difference between the toxic and essential levels of selenium to human health are very slight. Therefore, the current provisional guideline value for selenium(IV) in the World Health Organization’s «Guidelines for Drinking-water Quality» and in the European Drinking Water Directive is set to a maximum concentration of 10 µg/L.The anodic stripping voltammetric (ASV) technique performed on the unmodified scTRACE Gold can be used to determine concentrations as low as 0.5 µg/L selenium with a 30 s deposition time. These limits can be lowered even further by increasing the deposition time. The linear range at 30 s deposition time ends at approximately 100 μg/L. The scTRACE Gold electrode does not need extensive maintenance such as mechanical polishing. Measurements can be performed in the laboratory with the 884 Professional VA or alternatively in the field with the 946 Portable VA Analyzer. This method is suited for manual or automated systems.

Automated determination of the zirconium content of zirconium acetate, as well as other zirconium compounds which can be rendered soluble as zirconium acetate.

Quality and process control of biofuels require straightforward, fast and accurate analysis methods. Ion chromatography (IC) is at the leading edge of this effort. Traces of anions in a gasoline/ethanol blend can accurately be determined in the sub-ppb range after Metrohm Inline Matrix Elimination using anion chromatography with conductivity detection after sequential suppression. While the analyte anions are retained on the preconcentration column, the interfering organic gasoline/bioethanol matrix is washed away.Detrimental alkali metals and water-extractable alkaline earth metals in biodiesel are determined in the sub-ppm range using cation chromatography with direct conductivity detection applying automated extraction with nitric acid and subsequent Metrohm Inline Dialysis. Unlike high-molecular substances, ions in the high-ionic strength matrix diffuse through a membrane into the low-ionic water acceptor solution. In biogas reactor samples, low-molecular-weight organic acids stem from the biodegradation of organic matter. Their profile allows important conclusions concerning conversion in the anaerobic digestion reaction. Volatile fatty acids and lactate can be accurately determined by using ion-exclusion chromatography with suppressed conductivity detection after inline dialysis or filtration.

Voltammetry (VA) is a fast and established method for testing the remaining antioxidant content in industrial lubricants. The flexible and modular Metrohm VA system setup discussed in this White Paper delivers more repeatable and more reproducible results which fulfill all ASTM requirements. Additionally, users can automate the complete analysis process which makes it possible to run series of samples completely unattended.

OMNIS Client/Server boosts business performance with scalable server management, cutting costs by reducing hardware, energy use, and maintenance across locations.

Anionic surfactants can be titrated with cationic surfactants and vice-versa. The Bulletin describes a multitude of substances that can be determined in this fashion and specifies the respective working conditions and parameters. In contrast to the classic two-phase titration in accordance with Epton, the titration with the anionic and cationic surfactants electrodes can be performed without chloroform. Furthermore, the equivalence point of the titration is difficult to determine in some cases with the Epton method and the titration cannot be automated.In many cases, a surfactant ISE is a remedy that is both environmentally friendly and suitable here. It was developed specially for application with potentiometrically indicated surfactant determinations.

Many of the key factors that influence coffee taste correlate with chemical properties that can be measured. These include pH, titratable acidity, refractive index, and caffeine. Historically, many of these analyses have included long, manual sample preparation processes using the time-consuming, liquid chromatography (LC) technique. This Application Note looks at a faster, simpler, alternative method for analysis of key quality parameters in coffee using a single titration platform: OMNIS.

AOF (adsorbable organic fluorine) is used to screen for per- and polyfluorinated alkyl substances in aqueous matrices via pyrohydrolytic combustion and ion chromatography.

Combustion ion chromatography (CIC) measures AOX (adsorbable organically bound halogens, i.e., AOCl, AOBr, AOI) and AOF as well as CIC AOX(Cl) according to EN ISO 18127.

Harmful industrial flue gases like H2S and CO2 cause corrosion of pipes and damage the environment. Adding the correct amount of amines in scrubber solutions, e.g. ethanolamines and methylamines, will neutralize these gases («gas sweetening»). Non-suppressed cation analysis with direct conductivity detection is a straightforward and robust technique for the quantification of monoethanolamine (MEA), diethanolamine (DEA), triethanolamine (TEA), monomethylamine (MMA), dimethylamine (DMA), and trimethylamine (TMA) via ion chromatography. Thanks to the high capacity of the Metrosep C 6 column, large volumes can be injected without compromising the peak shapes. The analytical technique can be used at laboratory scale but also for process analysis.

Boric acid requires precise monitoring in the primary circuit to control nuclear reactor reactivity. The 2060 TI Process Analyzer monitors boric acid online in near-real time.

Ion chromatography (IC) is the method of choice to determine the concentration of common ions in water. This information is crucial as drinking water must meet certain standards to guarantee health (e.g., nitrite and nitrate), as well as technical suitability (e.g., corrosiveness of chloride and sulfate). The Eco IC is an ion chromatograph suitable for economical routine water analysis. Using an A Supp 17 anion column, the analysis of major anions in drinking waters is robust and can be performed at ambient temperatures without additional temperature conditioning.

This application focuses on the simultaneous analysis of cations and suppressed anions with a dual channel Metrohm IC operated by OpenLab CDS.

This Application Note presents an update to the standard AOAC method for total GOS determination in foodstuffs.

Worldwide, milk and dairy products are vital sources for human nutrition. A major component and energy source in dairy products is lactose. To efficiently metabolize lactose, the enzyme lactase is indispensable. However, globally nearly 70% of the population is lactose intolerant and they have difficulties to digest lactose. Lactose malabsorption leads to numerous gastrointestinal and extra-intestinal symptoms and other complaints with varying extents. Therefore, consumers rely on accurate food labels and for manufacturers appropriate sensitive analytical techniques are a must to comply with these demands. Ion chromatography with pulsed amperometric detection (IC-PAD) enables the determination of very low lactose contents. Validation according to AOAC requirements shows the high sensitivity and reliability of this method as a routine analysis.

This Application Note presents ion chromatography with pulsed amperometric detection as fast and reliable method to determine low level lactose in complex matrices such as infant formula.

NIRS enables rapid, chemical-free analysis of glucose, fructose, sucrose, and Brix in fruit juices without sample prep, offering a fast alternative to traditional methods.

Differential electrochemical mass spectrometry (DEMS) is used to monitor gaseous and volatile species during electrochemical reactions in situ.

Ion chromatography (IC) with suppressed conductivity detection has been approved by the U.S. Pharmacopeia (USP) as a validated method to quantify the monofluorophosphate (MFP) content in sodium monofluorophosphate. This Application Note shows that all acceptance criteria for the USP Monograph «Sodium Monofluorophosphate» are fulfilled and the procedure was approved as a validated USP method.

This White Paper explores the critical role of advanced online and inline process analysis in brine chlorine operations, emphasizing their advantages over traditional methods.

Monitoring organic additives in copper plating baths is crucial. The 2060 CVS Process Analyzer optimizes copper electroplating by providing precise bath control.

The alpha acid level (AA%) in hops plays a major role in the bitterness they can impart to beer. The AA% can vary between 1% up to 20% in hops. During boiling in the brewing process, alpha acids transform into iso-alpha acids which make the beer bitter. For this reason, it is important for brewers to know the exact AA value of the hops they use. The determination of AA% in hops with conductometric titration according to the EBC method 7.4 is shown in this Application Note.

Ethanol content can be quickly and easily determined in different wines during fermentation and afterwards for quality control using near-infrared spectroscopy.

Fresh coconut water quality is influenced by crop location, harvest timing, and storage duration, creating challenges for consistent industrial production. This application describes the analysis of the parameters Brix, conductivity, turbidity, pH value, and salinity in coconut water with the OMNIS NIR Analyzer Liquid. Near-infrared spectroscopy (NIRS) enables rapid, reagent-free multiparameter analysis without sample preparation, reducing reliance on conventional laboratory testing.

Manufacturers and laboratories must use validated methods to determine the zinc content in skin care products and pharmaceutical supplements to meet strict quality standards set by the United States Pharmacopeia and National Formulary (USP-NF). USP-NF has updated the zinc monograph (General Chapter <591>, Zinc Determination) and replaced the existing identification procedure of titration with ion chromatography (IC). The analysis involves separating Zn using a Metrosep A Supp 10 column followed by post-column reaction using 4-(2-pyridylazo)resorcinol and detection at 530 nm.

Application: Free and total carbohydrate determination in instant coffee with IC-PAD according to AOAC 996.04 and ISO 11292.

The basic chemicals industry is responsible for producing thousands of raw materials at very large scales. The industries downstream rely upon a certain level of chemical purity to manufacture their own goods, as certain impurities can cause major issues in various processes. During the production of the basic chemicals NaOH and KOH, electrolysis of saturated brine solutions with membrane-cells yield the product which is further concentrated by evaporation. Impurities from the salts used in the brine will also be concentrated. Typically, this impurity analysis is performed offline with various hazardous chemicals with varying shelf-lives. The Process Ion Chromatograph is able to perform the measurement described in ASTM E1787-16 online, ensuring quality product without the need for time-consuming, hazardous laboratory experiments.

Organic halides must be monitored in the environment. Combustion ion chromatography (CIC) is used for accurate halogen analysis in solids following EN 17813:2023.

Gold leaching by cyanidation requires precise monitoring of cyanide and gold. Online process analyzers perform such measurements, improving safety and compliance.

This Application Note describes carbonate determination with ion chromatography in a 50% sodium hydroxide solution. Sodium hydroxide solutions form carbonates through the absorption of carbon dioxide from ambient air. The carbonate content of an NaOH solution is determined using ion-exclusion chromatography with subsequent conductivity detection following inverse suppression. The samples are diluted 1:20 prior to the analysis and – in order to prevent CO2 absorption – stored in closed sample vessels.

This Application Note details a method to determine the peroxide value of edible fats and oils based on EN ISO 27107, EN ISO 3960, AOAC 965.33, Ph.Eur. 2.5.5, and USP<401>.

Copper is used widely in industrial cooling water systems for its heat transfer properties, although it is susceptible to corrosion. Corrosion can cause a loss of efficiency and eventually a failure of equipment, leading to costly maintenance, replacement, and downtime. Corrosion inhibitors (triazoles) can be added to the water chemistry, which form sparingly soluble protective layers on the surface of the metal. Triazole concentrations must be maintained to protect the copper, which necessitates regular concentration determinations in cooling water. The 2060 IC Process Analyzer with UV/VIS detection is well-suited for this application, able to precisely and reliably measure multiple ionic and UV-active compounds simultaneously in cooling water.

This Application Note presents a potentiometric titration method for a potassium bicarbonate and potassium carbonate assay meeting all USP General Chapter <1225> requirements.

Citric acid and oxalic acid are present in many products, such as foods or chemical solvents (e.g., decontamination solutions). Both acids are reducing agents and citric acid is additionally a powerful antioxidant. Due to their mutual impact (buffer effect), a content calculation is only possible with correction factors for each acid. A fast and accurate determination by potentiometric titration using the dEcotrode plus and sodium hydroxide as titrant can be realized in this Application Note.

Fresh as well as used petroleum products may contain acidic components as additives or degradation products. The acid number (AN) is a measure for the relative amount of acids present expressed as mg KOH per g sample. Moreover, AN is used as a quality parameter of lubricating oils both for assessing the quality of new formulations and as an indicator for the degradation of such formulations during service. The use of a pH electrode suitable for non-aqueous titrations ensures the reliable determination of the equivalence point. A flexible sleeve diaphragm facilitates its cleaning especially after use in heavily contaminated samples, such as in used engine oils. Using the correct electrode greatly increases the precision and reliability of the results. This Application Note describes the potentiometric determination of the acid number according to ASTM D664 and IP 177 using the pH electrode Solvotrode easyClean.

Monitoring sulfuric acid and zinc sulfate in the viscose wet-spinning process is essential. Online potentiometric titration and colorimetric analysis are recommended for this purpose.

The Bayer Process is the method used to refine alumina from bauxite ore, as smelting aluminum directly from alumina is much more cost- and energy-effective. In this process, "aluminate liquors" are created by digesting the crushed bauxite with CaO and NaOH at high temperatures. Additionally, the CaO causticizes carbonate which forms in the alkaline solution from organic degradation and CO2 absorption from the atmosphere. Contaminations are removed at various steps in the process, and the liquor is filtered from the alumina crystals before it is recycled back to the digestion step. Before the spent liquor can be reused, a determination of the concentrations of the total hydroxyl (“caustic”), carbonate, and alumina values is required. These parameters can be determined quickly via thermometric titration with the 2035 Process Analyzer.

In the Solvay process, ammonium hydrogen carbonate and table salt are converted to sodium hydrogen carbonate and ammonium chloride. Heating the former yields sodium carbonate (soda), an important raw material for the soap and glass industries. Ammonia is an incipient and is regenerated almost completely through conversion of the ammonium chloride with lime milk (Ca(OH)2).A Metrohm process analyzer monitors the ammonia content in the saturated table salt solution after absorption tower, thus guaranteeing a good product yield in the carbonization tower. Additional parameters which can be determined with the analyzer in the Solvay process include: alkalinity, carbonate, chloride, calcium oxide and carbon dioxide.

In power plants, corrosion is the greatest enemy. If corrosive impurities are present in the circuit streams (e.g., chlorides and hydroxides), deposition of an insulating layer of scale on the heat transfer surfaces occurs, resulting in costly and critical downtimes. To ensure high throughput of power plants, online analysis of critical parameters such as sodium is highly advantageous for safety, protection, and process optimization. With the 2035 Process Analyzer from Metrohm Process Analytics, operators gain the information they need to accurately identify trends, reduce downtimes, and address operational issues before costly problems arise.

Lithium is a soft alkali metal that is typically obtained from salt lake brines. Lithium is used for many applications, but especially for production of lithium-ion batteries in electric cars, mobile phones, and more. This Process Application Note presents a method to monitor lithium as well as other cations in brines by online process ion chromatography (IC), a multiparameter analytical technique that can measure ionic analytes in a wide range of concentrations.

Titration is an accurate and precise method that can be used to determine the pyrophosphate content in aqueous products. The OMNIS Titrator equipped with a dUnitrode delivers reliable determinations.

The presence of iron in drinking water can lead to an unpleasant taste, stains, or even growth of «iron bacteria» that can clog plumbing and cause an offensive odor. Over a longer period, the formation of insoluble iron deposits is problematic in many industrial and agricultural applications. To avoid these problems, the U.S. Environmental Protection Agency (EPA) defines the Secondary Maximum Contaminant Level (SMCL) for water treatment and processing plants as 0.3 mg/L Fe in drinking water.The voltammetric determination of the iron triethanolamine complex on the non-toxic Bi drop electrode allows both the detection at very low levels (limit of detection of 0.005 mg/L) and measurements in a wide range of concentrations up to 0.5 mg/L.

The main sources of nickel pollution are electroplating, metallurgical operations, or leaching from pipes and fittings. Catalysts for the petroleum and chemical industries are major application fields for cobalt. In both cases, the metal is either released directly, or via the waste water-river pathway into the drinking water system. Therefore in the EU the legislation specifies 20 µg/L as the limit value for the Ni concentration in drinking water.The simultaneous and straightforward determination of nickel and cobalt is based on adsorptive stripping voltammetry (AdSV). The unique properties of the non-toxic Bi drop electrode combined with AdSV results in an excellent performance in terms of sensitivity.

One way to maximize heat transfer efficiency and reduce costs in a power plant is by controlling the water chemistry in the cooling circuit. This cooling water is kept alkaline to maintain the protective oxide layer on the metal piping throughout the water circuit. However alkalinity above the recommended range increases the probability of scale formation (deposition), so it is buffered with carbonate (CO32-) and bicarbonate ions (HCO3-). Titration of the cooling water to pH 4.5 gives the so-called "M-Alkalinity" (methyl orange alkalinity), a measure of total alkalinity. Below this pH, there is no more alkalinity present, only free acid (H+), carbonic acid (H2CO3), and CO2.

Even in low concentration, sulfide ions cause odor and corrosion problems in ground water and waste water. They can release hydrogen sulfide in acidified water, which is toxic in even minuscule amounts. This Application Note describes the determination of sulfide concentration in water via direct measurement with the Ag/S-ISE in accordance with ASTM D4658.

To reduce the toxic effects of cadmium on the human body, as well as to limit the neurotoxic effects of lead, the provisional guideline values in the World Health Organization’s «Guidelines for Drinking-water Quality» are set to a maximum concentration of 3 µg/L for cadmium and 10 µg/L for lead. The completely mercury-free Bi drop electrode takes the next step towards converting voltammetric analysis into a non-toxic approach for heavy metal detection. Using this environmentally friendly sensor for anodic stripping voltammetry (ASV) allows the simultaneous determination of Cd and Pb in drinking water. The outstanding sensitivity is more than sufficient to monitor the provisional WHO guideline values.

In this Process Application Note, the analysis of low concentrations of calcium and magnesium (0–20 µg/L) in brine is addressed. The presence of calcium and magnesium can shorten the performance and lifetime of the membranes used in the chlor-alkali industry for the production of chlorine. Accurate online monitoring of the hardness is needed in several stages of the process. Other parameters such as acidity, carbonate, hydroxide, silica, alumina, ammonia, iodate and chlorine can also be analyzed online.

The size of the indigo molecule makes it difficult to dye synthetic fibers, but the large pores of cellulose (such as in cotton) accept it readily. Indigo is insoluble in water, so it must first be reduced to the water-soluble leuco-indigo form by sodium hydrosulfite in a strong alkaline bath. Good circulation within the bath is imperative for consistent dye coverage, but care must be taken not to introduce any oxygen. Fabrics must be oxidized between dips in the dye bath in order to set the indigo within the pores of the fibers, but multiple dips are necessary for darker, uniform coverage. Many parameters need to be monitored and controlled to ensure high quality of the end product: the pH value for proper NaOH (alkali) dosage, the concentrations of both hydrosulfite and indigo, as well as the temperature of the bath and even the redox potential.

To improve the performance of electrochemical energy storage devices like batteries and supercapacitors, one can focus on enhancing the ion conductivity (ƠDC) of the electrolyte. It is a common method for obtaining ƠDC values of different electrolyte systems, to carry out electrochemical impedance spectroscopy (EIS) experiments, at different temperatures, in a 2-electrode setup.

This Application Note describes the titration of acid value and free fatty acids in different edible oils, based on the standards EN ISO 660, USP<401>, and Ph.Eur. 2.5.1.

The acid number (AN) of insulating, transformer, and turbine oils is crucial to ensure safe operation, operating equipment control, and corrosion prevention. These oils generally have low AN specifications and their AN determination by manual color-indicator titration is difficult, especially when analyzing colored samples.Using a Titrator with a photometric sensor to detect the end point ensures that the titrations are always carried out under the same conditions. This greatly increases the precision and reliability of the results, which in turn results in improved monitoring for your operations.

Drinking water which has been disinfected via the ozonation process can contain undesirable levels of bromate, a carcinogen, via oxidation of bromide in the raw water. Already several agencies including the World Health Organization have recommended concentration limits for bromate set in place to limit its risks to our health. Ion chromatography is mentioned in several analytical standards for the determination of disinfection byproducts (DBP) including bromate, such as EPA 300.1, 317.0, 321.8, 326.0, ASTM D6581, ISO 11206, and ISO 15061. Monitoring trace levels of bromate online means higher throughput and less time spent performing manual laboratory tests, and ensures quality drinking water is produced.

Reliable monitoring of TBC in styrene according to ASTM D4590 requires an explosion-proof solution like the 2060 TI Ex Proof Analyzer.

Carbon capture systems strip carbon dioxide from flue gases. Online analysis of amines and carbon dioxide enhances amine usage efficiency and reduces operational costs.

Zinc is an essential trace element for humans. Excessive intake of zinc in higher concentrations can be harmful, however. There is no guideline value for zinc in the World Health Organization’s «Guidelines for Drinking-water Quality» because typical levels usually found in drinking water are of no concern. Anodic stripping voltammetry is a viable, less sophisticated alternative to atomic absorption spectroscopy (AAS) for the determination of zinc in drinking water. While AAS (and competing methods) can only be performed in a laboratory, anodic stripping voltammetric determinations can be used conventionally in the laboratory or alternatively in the field using with 946 Portable VA Analyzer. The determination is carried out on the scTRACE Gold electrode.

No health-based guideline value exists for zinc. However, to maintain good quality municipal drinking water, the United States Environmental Protection Agency (US-EPA) set a maximum concentration of 5 mg/L as the limit value. Typical concentrations in surface and ground waters are between 10–40 μg/L Zn, with values up to 1 mg/L in tap water. Anodic stripping voltammetry (ASV) on the ex-situ mercury film modified glassy carbon electrode provides a less complex alternative to atomic absorption spectroscopy (AAS) for zinc determination in drinking water.

The toxicity of antimony depends on its oxidation state: antimony(III) is more toxic than antimony(V). Due to its carcinogenicity, EU legislation specifies 5 µg/L and the World Health Organization (WHO) sets a maximum concentration of 20 µg/L as the Sb(III) limit value in drinking water.Straightforward determination using anodic stripping voltammetry provides a fast (analysis time under 10 minutes) and an ultra-sensitive tool for monitoring the antimony(III) concentration in drinking water. Measurements can be performed in the laboratory with the 884 Professional VA, or alternatively in the field with the 946 Portable VA Analyzer.

Bromide is ubiquitous in sea water, where it is present in concentrations of around 65 mg/L. By contrast, the maximum bromide concentration in drinking and ground water is usually less than 0.5 mg/L. A higher bromide content may indicate a contamination of the water caused by fertilizer, road salt or industrial waste water. This Application Note describes the determination of the bromide content in water via direct measurement with a Br ion-selective electrode in accordance with ASTM D1246.

This Application Note offers an easy way to determine the ammonia content in cacao nibs by using ion measurement, applying the standard addition technique in a reliable cost- and time-saving manner.

The guideline value for chromium in the World Health Organization’s (WHO) «Guidelines for Drinking-water Quality» is 50 µg/L. It should be noted here that chromium concentrations are often expressed as total chromium and not as chromium(III) or (VI). Chromium(VI) is responsible for changes in genetic material, and is found in significantly lower concentrations than Cr(III). Therefore an extremely sensitive method is required to monitor Cr(VI) in drinking water.The powerful adsorptive stripping voltammetry (AdSV) technique on the ex-situ mercury film modified glassy carbon electrode using DTPA as complexing agent can be used to determine such low concentrations.

Accurate analysis of complexing agents in galvanic baths is possible with inline Raman spectroscopy. This Application Note shows an example using a 2060 Raman Analyzer.

Nitric acid, phosphoric acid, and acetic acid are easily determined in etching baths using thermometric titration (TET). Compared to potentiometric titration, TET is faster and more convenient. Analysis is complete in less than two minutes.

The presence of acidic components in volatile solvents could be a result of contamination, decomposition during storage, distribution or manufacture. An increased acid content in solvents could lead to a variety of problems like shorter storage stability or chemical corrosion. Using the Optrode for indication, the acidity is determined by photometric titration with sodium hydroxide as titrant and phenolphthalein as indicator. If the volatile solvent is water soluble, it is dissolved in deionized water, if not, it is dissolved in carbon-dioxide free ethanol.

To reduce the toxic effects of cadmium on the kidneys, skeleton, and the respiratory system, as well as the neurotoxic effects of lead, the provisional guideline values in the World Health Organization’s (WHO) «Guidelines for Drinking-water Quality» are set to a maximum concentration of 3 µg/L for cadmium and 10 µg/L for lead.The powerful anodic stripping voltammetry (ASV) technique on the ex-situ mercury film modified glassy carbon electrode is more than sufficient to monitor the proposed WHO guidelines for Cd and Pb in drinking water.

Fertilizers are applied in the agricultural sector to provide more essential nutrients to growing plants. The so-called «NPK» fertilizers provide such nutrients to plants with its three main components (N – nitrogen, P – phosphorous, K – potassium). In fertilizers, nitrogen is mainly provided in three forms: as ammonium nitrate (NH4NO3), ammonia (NH3), and urea (H2NCONH2). Determination of the individual nitrogen-contributing components is often laborious work. Thermometric titration offers the possibility to rapidly determine the amount of ammoniacal nitrogen and urea nitrogen in a single titration using sodium hypochlorite as titrant.

This application highlights Metrohm’s XTR® technology to identify colored polymers by extracting the Raman signal from spectra with strong background fluorescence.

Due to the toxicity and the detrimental effects of nickel and cobalt on human health, their concentrations in drinking water must be controlled. Therefore, EU the legislation specifies 20 µg/L as the limit value for nickel in drinking water. The current provisional guideline value for Ni in the World Health Organization’s «Guidelines for Drinking-water Quality» is set to a maximum concentration of 70 µg/L. To monitor the concentrations of Ni and Co with the 884 Professional VA, a method for simultaneous determination on the glassy carbon electrode (GC-RDE) modified with a Bi film is used.

Forensic institutes examine terrorist attacks and warfare agents via trace detection analysis of the used explosives and their residuals. Of particular importance is the acquisition of «chemical fingerprints» for criminal investigation departments and governmental security agencies. Institutes for public health and environmental protection analyze such compounds that can contaminate the underlying soil and infiltrate ground water.Forensic investigation with ion chromatography (IC) using suppressed conductivity detection allows a sensitive and robust determination of anionic contaminants such as chlorate, thiosulfate, thiocyanate, and perchlorate next to the common inorganic anions over a broad concentration range.

Kjeldahl method is used to determine the nitrogen content in organic and inorganic samples. Kjeldahl consists of three steps: digestion, distillation, and titration. During the catalytic digestion step, organic nitrogen is converted into ammonium. Sodium hydroxide is added just before the distillation step for converting ammonium into ammonia. Through steam distillation the latter is transferred into the receiver vessel containing an absorbing agent (e.g., boric acid). Finally, the separated ammonia is titrated against sulfuric acid. Protein content in samples can also be determined from the nitrogen content obtained by Kjeldahl setup. USP describes the titration method to determine nitrogen content in organic products using Kjeldahl nitrogen setup. This Application Note illustrates nitrogen determination in heparin sodium.

Nitrogen-based compounds are widely distributed in the environment and are essential growth nutrients for photosynthetic organisms. Therefore, it is important to monitor and control the amount of nitrogen compounds which are released into the environment.In this Application Note, a method to determine the nitrogen content in water by Kjeldahl digestion and distillation followed by a photometric or potentiometric titration according to ASTM D3590 is presented. The universality, precision, and reproducibility of the Kjeldahl method have made it the internationally recognized method for e.g. estimating the protein content in many matrices and it is the standard method to which all other methods are judged against.

Groundwater contains many minerals, but can be contaminated by sodium-rich leachate from landfills. Accurate Na determination in water is possible following AOAC 976.25 using the Na-ISE.

This Application Note presents a modified time-saving method to determine iodine value (IV) in edible oils based on several standards (EN ISO 3961, ASTM D5554, etc.).

The Devanathan-Stachurski cell (or «H cell») is successfully used to evaluate the permeation of hydrogen through sheets or membranes. As small amounts of hydrogen pass through the sheet or membrane, a very sensitive potentiostat is required for its detection. A study of the hydrogen permeation properties of different iron sheets is discussed in this Application Note while taking the instrumental requirements into account.

Phenol is a key chemical intermediate used to manufacture polymers, synthetic fibers, resins, detergents, herbicides, and pharmaceuticals. Most phenol production relies on the cumene hydroperoxide route, in which acid cleavage generates phenol and acetone. This Process Application Note describes the online potentiometric titration of sulfuric acid using the 2060 TI EX Proof Process Analyzer to maintain tight process control, enhance phenol quality, and reduce chemical consumption.

The standardization of the cationic surfactant TEGOtrant is performed using potentiometric titration as well as near-infrared spectroscopy (NIRS) in this application.

Yaba, produced in Southeast Asia, is a popular drug of abuse and is actively targeted by police squads. Two strong and highly addictive stimulants make up Yaba: caffeine, which comprises up to 60% of each tablet, and methamphetamine at approximately 20%. Identifying these two active ingredients in different proportions in a colorful tablet with other excipients could be an analytical nightmare. With handheld Raman, bulk material identification is achieved in seconds onsite with simple point-and-shoot analysis. SERS (surface-enhanced Raman spectroscopy) analysis is used to detect the minor component in mixtures without interference from fillers, dyes, and coatings. MIRA DS is uniquely capable of both analyses—Raman testing positively identifies caffeine in Yaba, while methamphetamine can be detected with SERS sampling. This application describes quick, dual analysis of Yaba tablets with MIRA DS.

Nitrosamine presence in medicines, even at trace level poses high safety risks to patients (carcinogenic). Nitrosamine formation can be avoided by controlling and monitoring the nitrite concentration in pharmaceutical products and substances. This Application Note describes the analysis of nitrite in duloxetine hydrochloride with ion chromatography (IC).

Permanganate absorption number (PAN) analysis per ISO 8660 ensures caprolactam purity, a precursor of Nylon 6. This application describes real-time, continuous PAN monitoring.

Excess sodium intake increases the risk of health issues. Ion-selective electrodes (ISEs) offer a fast, accurate, and cost-effective method for measuring sodium in food.

This Process Application Note deals with online measurements of ammonia, nitrite, and nitrate in wastewater treatment plants. These nitrogen compounds are analyzed simultaneously using a drift-free colorimetric measurement in a multi-parameter process analyzer from Metrohm Process Analytics.

Salmon farms are becoming ever more popular. Strong population growth increases the demand for salmon which has an effect on their cultivation. Ever more fish live in limited space in open net cages. Parasites such as salmon lice can multiply quickly due to the high density of fish. One possibility of fighting the lice is to use baths with weak concentrations of H2O2. The salmon are treated in these concentrations for up to 20 minutes until the lice fall away and die. While it is true that hydrogen peroxide decomposes relatively quickly, it is nonetheless deadly for salmon in higher concentrations. The concentration must therefore always lie within the specifications during treatment. Our process analyzer requires less than two minutes per titration. This means that it permits more concentration determinations per treatment and always guarantees the correct dosage.

Incineration flue gas requires treatment such as wet scrubbing. The 2060 VA Process Analyzer monitors heavy metals in the scrubbing water, ensuring compliance.

brightRC enables reliable CVS (or CPVS) brightener quantification without repeated standard additions, especially for additive systems with nonlinear signal behavior. By using external response curve (RC) calibration and flexible regression, it avoids systematic errors inherent to linear standard addition methods and significantly reduces analysis time. This makes brightRC ideal for high throughput routine control in stable copper plating baths.

TacticID-1064 ST is a handheld Raman device that can identify materials through paper, plastic, glass, and multilayer packaging, reducing exposure risks and eliminating the need to open containers.

Online acid number analysis in various oil products is possible with thermometric catalytic titration according to ASTM D8045 using the 2060 TI Ex Proof Process Analyzer.

NIRS can simultaneously measure several quality parameters in hops like cohumulone, hop oils, and moisture content, the hop storage index (HSI), and alpha and beta acids.

Lithium-ion (Li-ion) battery electrolyte quality is essential for performance, stability, and safety reasons. Ion chromatography is an accurate method for electrolyte analysis.

Determination of Total Acid Number (TAN) values in biodiesel to <0.05 mg KOH/g sample.

Monitoring the range of organic acids in wine is crucial to improve flavor and quality, and to fulfill universal standardized criteria such as the International Code of Oenological Practices. Analytically, organic acids can be properly determined with ion chromatography (IC) and suppressed conductivity detection. As a multicomponent method, inorganic acids can also be resolved which are also valuable tracers for wine quality and taste. This Application Note presents two IC methods for wine quality analysis: a fast isocratic screening method of major organic acids and anions including sulfite, and a complex monitoring method with a binary gradient to separate 15 organic acids. Inline Ultrafiltration was used for economical sample treatment.

The objective of validation of an analytical procedure is to demonstrate that it is suitable for its intended purpose. Recommendations for the validation of analytical methods can be found in ICH Guidance Q2(R1) Validation of Analytical Procedures: Text and Methodology and in USP General Chapter <1225> Validation of Compendial Procedures. The goal of this white paper is to provide some recommendations for the validation of titration methods.

This white paper presents IC-MS as powerful analysis technique. This multiparameter method determines various analytes such as inorganic cations and amines in one run.

Higher levels of copper in drinking water are usually caused by corrosive action of water leaching copper from copper pipes. While copper is an essential nutrient for the human organism, ingestion of higher concentrations have an adverse effect on human health. The current World Health Organization’s «Guidelines for Drinking-water Quality» recommend a maximum concentration of 2000 μg/L. With a limit of detection (LOD) of 0.5 μg/L, anodic stripping voltammetry is a viable, less sophisticated alternative to atomic absorption spectroscopy (AAS) for the determination of copper in drinking water. While AAS (and competing methods) can only be performed in a laboratory, anodic stripping voltammetry can be used conventionally in the laboratory or alternatively in the field with the 946 Portable VA Analyzer. The determination is carried out on the scTRACE Gold electrode.

Bismuth is considered as a metal with a very low toxicity. In high concentrations toxic effects have been described, however. There is no guideline value for bismuth in the World Health Organization’s «Guidelines for Drinking-water Quality» because typical levels usually found in drinking water are of no concern. Anodic stripping voltammetry is a viable, less sophisticated alternative to atomic absorption spectroscopy (AAS) for the determination of bismuth in drinking water. While AAS (and competing methods) can only be performed in a laboratory, anodic stripping voltammetry can be used in the laboratory or alternatively in the field with the 946 Portable VA Analyzer. The determination is carried out on the scTRACE Gold electrode.

Arsenic is ubiquitous in the earth’s crust in low concentrations. Elevated levels can be found in mineral deposits and ores. Arsenic from such deposits leaches into the groundwater in the form of arsenite (AsO33–) and arsenate (AsO43–), causing its contamination. As(III) is more toxic than As(V) and shows higher mobility in the environment. The selective determination of this species is possible using the method described in this document.With a limit of detection (LOD) of 0.3 μg/L, anodic stripping voltammetry allows speciation, i.e. the specific determination of As(III). While atomic absorption spectroscopy (AAS) (and competing methods) can only determine the total element concentration, anodic stripping voltammetry is selective to the As(III) oxidation state. The determination is carried out on the scTRACE Gold electrode.

The determination of the acid number plays a significant role in the analysis of petroleum products. This is manifested in the numerous standard procedures in use over the world (internal specifications of multinational companies, national and international specifications of ASTM, DIN, IP, ISO, etc.). These procedures differ mainly in the composition of the used solvents and titrants.This bulletin describes the determination of the acid number in petroleum products by applying different types of titration.The potentiometric determination is described according to ASTM D664, the photometric according to ASTM D974 and the thermometric titration according to ASTM D8045.

As a key quality control parameter for fats and oils, the iodine value (IV) represents the degree of unsaturation. In this Application Note, excess Wijs reagent reacts with double bonds in the sample, and the iodine formed is quantified by thermometric back-titration with sodium thiosulfate. Thermometric endpoint titration (TET) provides a rapid, robust alternative to potentiometric methods by detecting the reaction enthalpy change without requiring sensor maintenance.

This Application Note shows the rapid, non-destructive identification of isopropyl alcohol from two manufacturers using Raman spectroscopy following the creation of a suitable library. The measurements with the hand-held Raman spectrometer Mira M-1 require no sample preparation and provide immediate results that identify the samples unambiguously.

Vitamin C, also known as ascorbic acid or L-ascorbic acid, is an essential nutrient involved in the repair of tissues and the enzymatic production of certain neurotransmitters. It is required for the functioning of several enzymes and immune performance, and is also an important antioxidant. This nutrient is found in many foods and is often used as a dietary supplement.This Application Note describes the photometric determination of ascorbic acid according to the standard ISO 6557-2. To increase the objectivity on the determined equivalence point and the reproducibility of the results, an autotitrator equipped with a photometric sensor, the Optrode, is used. The titrant 2,6-Dichlorophenol-indophenol (DCIP or DPIP) simultaneously serves as titrant and indicator.

This Application Note describes the photometric determination of zinc sulfate using the Optrode at a wavelength of 610 nm. Complexometric titration of zinc requires EDTA as titrant and Eriochrome Black T as indicator. The method fully complies with Ph. Eur. and USP.

Lithium is a soft metal which is used for many applications, such as production of high-temperature lubricants or heat-resistant glass. Furthermore, lithium is used in large quantities in for battery production. It is obtained from brines and high-grade lithium ores. Depending on the lithium concentration, extraction may or may not be economically viable.This Application Note demonstrates a method to determine the lithium concentration in brines by potentiometric titration. Lithium and fluoride precipitate in ethanol as insoluble lithium fluoride. Using ammonium fluoride as the titrant and a fluoride ion-selective electrode (ISE), determination via potentiometric titration is possible. This method is more reliable, faster, and less expensive than the determination of lithium in brine by other more sophisticated techniques such as atomic absorption spectroscopy (AAS).

Boehm titration is a quantitative analysis of functional groups on the surface of carbon materials based on their reactions with basic solutions of NaHCO3 (pKa = 6.4), Na2CO3 (pKa = 10.3), and NaOH (pKa = 15.7). This is a cost-efficient method that gives absolute values with high precision of the accessible, mainly oxygen-containing functional groups on the surface. Originally, Boehm titration was developed for carbon materials like conductive carbon black (CCB), activated carbon, porous carbon, and graphite. Modern carbon-based materials like graphene, graphene oxide (GO), or carbon nanotubes can also be analyzed this way.

Arsenic is ubiquitous in the earth’s crust in low concentrations. Elevated levels can be found in mineral deposits and ores. Arsenic from such deposits leaches into the groundwater in the form of arsenite (AsO33–) and arsenate (AsO43–), causing its contamination. In addition to the arsenic originating from natural sources, industry and agriculture contribute to the contamination to a lower extent. The guideline value for inorganic total arsenic in the World Health Organization’s «Guidelines for Drinking-water Quality» is set to 10 μg/L. With a limit of detection (LOD) of 0.9 μg/L, anodic stripping voltammetry is a viable, less sophisticated alternative to atomic absorption spectroscopy (AAS) for the determination of arsenic. While AAS (and competing methods) can only be performed in a laboratory, anodic stripping voltammetry can be used conventionally in the laboratory or alternatively in the field using the 946 Portable VA Analyzer. The determination is carried out on the scTRACE Gold electrode.

Mercury and its compounds are toxic. The highest risk is posed by chronic poisoning with mercury compounds ingested with food. A significant part of the mercury present in the environment is of anthropogenic origin. Considerable sources are coal-fired power plants, steel, and nonferrous metal production, waste incineration plants, the chemical industry, or artisanal gold mining where the use of elemental mercury for the extraction of gold from the ore is still common. The guideline value for inorganic mercury in the World Health Organization’s «Guidelines for Drinking-water Quality» is set to 6 μg/L.With a limit of detection (LOD) of 0.5 μg/L, anodic stripping voltammetry is a viable, less sophisticated alternative to atomic absorption spectroscopy (AAS).While AAS (and competing methods) can only be performed in a laboratory, anodic stripping voltammetry can be used conventionally in the laboratory or alternatively in the field with the 946 Portable VA Analyzer. The determination is carried out on the scTRACE Gold electrode.

Iron is an essential element in human nutrition. It can be present in drinking water as a result of water treatment or from corrosion in the water piping system. There is no guideline value for iron in the World Health Organization’s «Guidelines for Drinking-water Quality» because typical levels usually found in drinking water are of no concern. However, there are national limit values in various countries. The European Union has set a guideline indicator value for iron of 200 μg/L. Voltammetry is a viable, less sophisticated alternative to atomic absorption spectroscopy (AAS) for the determination of iron in drinking water. While AAS (and competing methods) can only be performed in a laboratory, anodic stripping voltammetric determinations can be done used conventionally in the laboratory or alternatively in the field using the with 946 Portable VA Analyzer. The determination is carried out with adsorptive stripping voltammetry (AdSV) using 2,3-dihydroxynaphthalene (DHN) on the scTRACE Gold electrode.

Nickel is widely used in stainless steel production. At high enough concentrations, it is known to cause allergic reactions when in contact with skin. Drinking water may be contaminated by taps which are made from metals containing nickel. The guideline value for nickel in the World Health Organization’s «Guidelines for Drinking-water Quality» is set to 70 μg/L. National limit values of typically lower at e. g. 20 μg/L. Cobalt usually occurs associated with nickel and can be found in smaller concentrations besides nickel. Adsorptive stripping voltammetry is a viable, less sophisticated alternative to atomic absorption spectroscopy (AAS) for the determination of nickel and cobalt in drinking water. While AAS (and competing methods) can only be performed in a laboratory, adsorptive stripping voltammetric determinations can be used in the laboratory or alternatively in the field with the 946 Portable VA Analyzer. The determination is carried out on a bismuth film applied to the scTRACE Gold electrode.

Thermometric titration can determine the total acid number (TAN) of various crude oil products according to ASTM D8045 without requiring any sensor maintenance.

Identification of individual polymers with FT-IR spectroscopy can be a challenge due to sample inhomogeneity especially when larger sample sizes need to be analyzed. This application note demonstrates that the DS2500 Solid Analyzer operating in the visible and near infrared spectral region (Vis-NIR) provides a reliable and fast solution for the identification of high-density polyethylene (HDPE), low-density polyethylene (LDPE), and polypropylene (PP). With no sample preparation or chemicals needed, Vis-NIR spectroscopy allows the identification of larger inhomogeneous sample amounts in less than a minute.

About 20% of our sugar comes from sugar beet crops, mostly grown in Europe and the U.S. where the climate is temperate, whereas the other 80% is produced from sugar cane in tropical areas. Lime salts and pH are very important factors which are controlled during the sugar manufacturing process. Complexometric titration is often used to determine the concentration of lime salts in such kinds of samples. This Application Note presents a more robust method for determining calcium compounds in sugar beet juice. Subjectivity of color change determination is eliminated by using an ion selective electrode (ISE).

Lithium iron phosphate batteries offer users safety and durability. Polarographic speciation evaluates Fe(II) and Fe(III) in cathode material, useful for several tests.

This Application Note describes the determination of aluminum in samples containing silicon dioxide using thermometric titration and EDTA as the titrant. Excess EDTA is titrated with a Cu2+ solution of known concentration. The initial, uncomplexed Cu2+ ions react immediately with the H2O2 present in the solution, leading to a recognizable sudden increase in temperature.

Determination of the density of polyethylene (PE) (ASTM D792) is normally a challenging procedure due to reproducibility difficulties. Measurement via FT-IR can be problematic when larger sample sizes must be analyzed due to sample inhomogeneity. This application note demonstrates that the DS2500 Solid Analyzer operating in the visible and near-infrared spectral region (Vis-NIR) provides a reliable and fast solution for determination of the density of PE. With no sample preparation or chemicals needed, Vis-NIR spectroscopy allows the analysis of larger, inhomogeneous sample sizes of PE in less than a minute.

This Application Note presents a complementary method that allows a consecutive determination after the sample preparation (digestion) of both metal ions in one beaker with an optical sensor and xylenol orange as an indicator.

This Application Bulletin shows the determination of the total base number in petroleum products by applying different titration types according to various standards.

One of the major sources of fluoride intake for humans comes from foodstuff, such as tea. Tea actually has one of the highest potentials to increase the daily fluoride intake. Excessive fluoride intake may lead to dental or skeletal fluorosis. The World Health Organization does not recommend consuming water with a fluoride content higher than 1.5 mg/L. In the presented method according to DIN 10807, the fluoride content can be assessed quickly with an ion selective electrode.

Specialty chemicals have to fulfill multiple quality requirements. One of these quality parameters, which can be found in almost all certificates of analysis and specifications, is the moisture content. The standard method for the determination of moisture content is Karl Fischer titration.This method requires reproducible sample preparation, chemicals, and waste disposal. Alternatively, near-infrared spectroscopy (NIR) can be used for the determination of moisture content. With this technique, samples can be analyzed without any preparation and without using any chemicals.

Alkaline additives in engine lubricants are used to prevent the build-up of acids and as a result, they inhibit corrosion. The total base number (TBN) indicates the amount of basic additives present in samples and thus can be used as a measure for the degradation of the lubricant. The standard test method for TBN in lubricants is potentiometric titration according to ASTM D2896. This method requires the use of toxic reagents involves a labor-intensive cleaning procedure. In contrast to the primary method, near-infrared spectroscopy (NIRS) is a fast analytical technique which does not produce any chemical waste and completes the TBN analysis in less than one minute.

This Application Note documents the suitability of hand-held Raman spectrometers, e.g., the Mira M-1, for the identification and differentiation of salts such as carbonates, phosphates, and sulfates. The focus of the work was the rating of the influence of the cationic part and of the crystal water on the Raman spectroscopy identification of the salts.

The vaping and electronic cigarette industries have grown impressively in the past decade. The mixtures used in these products are usually called «e-liquid», «e-fluid», or «e-juice». To ensure the quality of these e-liquids, testing the most important quality parameters, such as nicotine content, is required. Nicotine in tobacco is usually determined by gas chromatography or liquid chromatography. Aqueous acid base titration is a much more affordable alternative for this determination. As e-liquids do not contain other components which might interfere with the titration, the aqueous acid base titration presented in this Application Note can be applied for nicotine determination. This method is an affordable and reliable way to determine the nicotine content in e-liquids and their nicotine starting material, ensuring the quality of these products.

Polypropylene (PP) is a general purpose resin widely used in industries such as electronic manufacturing and construction, as well as in packaging materials. PP resins must be melted first in order to be formed into the intended shape, and therefore flow properties are important characteristics which affect the production process. The standard procedure to analyze melt flow rate (MFR) requires a significant amount of work with packing the sample, preheating, and cleaning. With no sample preparation or chemicals needed, Vis-NIR spectroscopy allows the analysis of MFR in less than a minute.

Near-infrared spectroscopy saves time and resources by simultaneously measuring key quality parameters like lactose, moisture, fat, and protein content in milk powder.

Raman spectroscopy can easily monitor polymerization by tracking monomer consumption and polymer formation, providing a valuable tool for polymer manufacturers.

NIR spectroscopy offers fast, chemical-free analysis of ash, protein, moisture, and rheological properties in flour – ideal for routine lab or atline quality control.

The Kraft process is the dominant pulping process in the pulp and paper industry with the highest chemical recovery efficiency. In order to run each part of the papermaking process optimally, constant quality checks and analyses should be performed. This Process Application Note illustrates the straightforward online analysis of alkali (active, effective, total titratable alkali (TTA)), carbonate, hydroxide, sulfide and the causticizing degree (CE%) in pulping liquors using a 2060 Process Analyzer from Metrohm Process Analytics.

Acid throwing, a historical method for retribution against women, has become a modern threat of a different nature. Concentrated acids and other corrosive substances have emerged as modern tools of social violence. Aggressors use common plastic containers with openings that create a powerful directional spray, such as lemon juice squeeze bottles. Sulfuric and phosphoric acids were chosen for analysis here due to their highly corrosive nature- acid attacks in London most commonly use sulfuric, phosphoric, and nitric acids.2017 saw a remarkable number of acid attacks in the UK, with reported incidences averaging 2x a day. Detection and regulation of acids may contribute to prevention of this social scourge.