Applikasjoner

This article demonstrates the utility of portable Raman spectroscopy as a versatile tool for process analytical technology (PAT) for raw material identification, in-situ monitoring of reactions in developing active pharmaceutical ingredients (APIs), and for real-time process monitoring. Raw material identification is done for verification of starting materials as required by PIC/S and cGMP, and can be readily done with handheld Raman. Portable Raman systems allow users to make measurements to bring process understanding and also provide proof of concept for the Raman measurements to be implemented in pilot plants or large-scale production sites. For known reactions which are repetitively performed or for continuous online process monitoring of reactions, Raman provides a convenient solution for process understanding and the basis for process control.

Although the process of building, validating and using a method is well-defined through software, the robustness of the method is dependent on proper practice of sampling, validation, and method maintenance. In this document, we will detail the recommended practices for using the multivariate method with NanoRam-1064. These practices are recommended for end users who are in the pharmaceutical environment, and can expand to other industries as well. This document aims to serve as a general reference for NanoRam-1064 users who would like to build an SOP for method development, validation and implementation.

Raman spectroscopy’s use for process analytics in the pharmaceutical and chemical industries continues to grow due to its nondestructive measurements, fast analysis times, and ability to do both qualitative and quantitative analysis. Spectral preprocessing algorithms are routinely applied to quantitative spectroscopic data in order to enhance spectral features while minimizing variability unrelated to the analyte in question. In this technical note we discuss the main preprocessing options pertinent to Raman spectroscopy with real applications examples, and to review the algorithms available in B&W Tek and Metrohm software so that the reader becomes comfortable applying them to build Raman quantitative models.

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.

This Application Bulletin gives an overview of the volumetric water content determination according to Karl Fischer. Amongst others, it describes the handling of electrodes, samples, and water standards. The described procedures and parameters comply with the ASTM E203.

This Application Bulletin gives an overview of the coulometric water content determination according to Karl Fischer.Amongst others, it describes the handling of electrodes, samples, and water standards. The described procedures and parameters comply with the ASTM E1064.

Application Bulletin AB-076 contains a description of the polarographic determination of low concentrations (1–100 mg/L) of NTA and EDTA in bodies of water. NTA, EDTA and citrate have gained in importance as complexing agents and builders due to the fact that the laws of some countries have made it necessary to find a substitute for phosphates in detergents.This Bulletin describes the determination of larger quantities of complexing agents in detergents using potentiometric titration. The ion-selective copper electrode (Cu-ISE) is used here as the indicator electrode. The determination of complexing agents is not disturbed by the other constituents often present in detergents.

The bromine number and bromine index are important quality control parameters for the determination of aliphatic C=Cdouble bonds in petroleum products. Both indices provide information on the content of substances that react withbromine. The difference between the two indices is that the bromine number indicates the consumption of bromine in gfor 100 g sample and the bromine index in mg for 100 g sample.This Application Bulletin describes the determination of the bromine number according to ASTM D1159, ISO 3839, BS2000-130, IP 130, GB/T 11135 and DIN-51774-1. The bromine index determination for aliphatic hydrocarbons is described according to ASTM D2710, IP 299, GB/T 11136 and DIN 51774-2. For aromatic hydrocarbons the determination of the bromine index is described according to ASTM D5776 and SH/T 1767. UOP 304 is not recommended for the determination of the bromine number or bromine index because its titration solvent contains mercuric chloride.

Only coulometric Karl Fischer titration can determine low water contents with sufficient accuracy.This Application Bulletin describes the direct determination according to ASTM D6304, ASTM E1064, ASTM D1533, ASTM D3401, ASTM D4928, EN IEC 60814, EN ISO 12937, ISO 10337, DIN 51777, and GB/T 11146. The oven technique is described according to ASTM D6304, EN IEC 60814, and DIN 51777.

The titrimetric determination of nonionic surfactants on the basis of polyoxyethylene adducts (POE adducts) is described in the Bulletin. The basis for the determination is the transfer of the nonionic surfactant into a pseudo-cation compound and its precipitation titration with sodium tetraphenylborate (Na-TPB). The NIO electrode is used for the indication of the potentiometric titration. This Bulletin describes determinations in raw products, formulations and wastewater and draws attention to special features, possibilities, limits and disruptions.

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.

The two potentiometric titration methods described here allow the determination of the content of commercial betaine solutions. Neither method is suitable for determining the betaine content of formulations. The possibilities and limits of both methods are described and distinctive features and possible sources of interference are mentioned. The Bulletin explains the most important theoretical principles and is intended to help users to develop their own product-specific titration methods.

The present Bulletin offers an overview of the multitude of surfactants and pharmaceuticals that can be determined with potentiometric titration. Metrohm provides five different surfactant electrodes for indicating the titration endpoint: the Ionic Surfactant, the High Sense, the Surfactrode Resistant, the Surfactrode Refill and the NIO Surfactant electrode. The manufacture of the respective titrants and their titer determination are described in detail. In addition to this, the Bulletin contains a tabular overview of more than 170 proven applications from the area of surfactant and pharmaceutical analysis. This guideline leads you reliably to your destination: At a glance you can see from the table which surfactant electrode and which titrant are optimally suitable for your product.

On the basis of a multitude of practical examples, this Bulletin describes the potentiometric two-phase titration of ionic surfactants in raw materials and many other formulations.Two surfactant electrodes – the Surfactrode Resistant and the Surfactrode Refill – make it possible to perform this type of surfactant titration, analogous to the classic "Epton titration", with a high degree of automation. The achieved results correlate very well with those of Epton titration. The toxic, carcinogenic and environmentally hazardous chloroform can be replaced by other solvents such as methyl iosbutyl ketone or n-hexane.

Two-phase titration with potentiometric indication is a universal method for the determination of ionic surfactants in detergents. The results obtained are comparable to those with the classic two-phase titration in accordance with Epton (mixed indicator system disulfine blue / dimidium bromide). The present Bulletin addresses various parameters that could have an influence on potentiometric surfactant titration. The information provided makes it possible for the user to determine precisely the anionic surfactant content in practically all formulations.

Generally speaking, the gas extraction or oven method can be used for all samples which release their water when they are heated up. The oven method is indispensable in cases in which the direct volumetric or coulometric Karl Fischer titration is not possible, either because the sample contains disruptive components or because the consistency of the sample makes it very difficult or even impossible to transfer it into the titration vessel.The present Application Bulletin describes automatic water content determination with the aid of the oven technique and coulometric KF titration, using samples from the food, plastic, pharmaceutical and petrochemical industry.

This Application Bulletin provides information regarding the MATi 10 (Metrohm Automated Titration) system. MATi 10 is a completely configured system for automatic volumetric Karl Fischer titration with which the water content in liquid and solid samples can be determined. Up to 24 samples can be analyzed directly in 75 mL titration vessels. The samples are weighed into the titration vessels and covered with an aluminum foil. This prevents falsification of the water content.

The present Application Bulletin contains NIR applications and feasibility studies for NIRSystems devices in the chemical industry. Qualitative and quantitative analyses of a wide variety of samples are part of this bulletin. Each application describes the instrument that was originally used for the analysis, as well as the system recommended for the analysis and the results that were achieved thereby.

MATi 4 (Metrohm Automated Titration) is a configured system for automated water content determination in liquid samples using coulometric Karl Fischer titration. The maximum sample volume is 5 mL. Up to 160 samples are filled in glass vials and sealed with lids. This ensures that the water content in the samples remains constant. The samples are aspirated and transferred into the coulometric cell through a needle. The tiamo™ software controls the system.

Pyrithione complexes, such as zinc pyrithione (ZnPT), copper pyrithione (CuPT), and sodium pyrithione (NaPT), are used as fungicides and bactericides. ZnPT is used in the treatment of skin conditions such as seborrheic dermatitis or dandruff. Furthermore, ZnPT is sometimes used as an antibacterial agent in paints to prevent algae and mildew growth. CuPT is primarily in use as a biocide to prevent biofouling of surfaces submerged in water. Meanwhile, NaPT is used as antifungal agent for treatment of mycosis, such as athlete’s foot. The different pyrithione complexes are determined by iodometric titration using a maintenance-free Pt Titrode for the indication.

This method is applicable to all samples containing glycerin in the absence of other triols or other compounds that react with periodate to produce acidic products. Glycerin may be determined in the presence of glycols. A periodate solution reacts slowly with diols and triols in acidic aqueous media at room temperature. A quantitative amount of formic acid is generated from the reaction with glycerin (a triol). The reaction with diols produces neutral aldehydes. The amount of formic acid generated by this reaction is determined by titration against sodium hydroxide.

Determination of zinc, sodium, ammonium, and manganese in the presence of magnesium and calcium in an extract of a zinc compound using cation chromatography with direct conductivity detection.

Determination of sodium, potassium, calcium, and magnesium in the water soluble fraction of a washing powder using cation chromatography with direct conductivity detection.

Determination of traces of methylamine, dimethylamine, and trimethylamine in methylpyrrolidone using cation chromatography with direct conductivity detection.

2-amino-N-(2,2,2-trifluoroethyl)-acetamide is a organic building block for synthesis of pharmaceutical products. Its purity is crucial for the success of the respective synthesis step. 2,2,2-trifluoroethylamine, glycine, and inorganic cations are of interest. Their total peak area is required to be < 2 % of the peak area of all peaks above the reporting level. Separation and quantification is achieved on a Metrosep C 4 - 250/4.0 cation column.

Lanthanum (La) is a transition metal which oxidizes easily in air to lanthanum(III) oxide. This oxide, as well as salts resulting from its dissolution in acid and recrystallization, is a component of different catalysts. Here, a lanthanum(III) acetate solution prepared by dissolution of lanthanum(III) oxide in acetic acid, has to be tested for a sodium contamination. The high concentration of La3+ is complexed by the dipicolinic acid in the eluent and forms anionic complexes. These complexes are eluted in the front and therefore do not interfere with the sodium impurity as well as other cations such as ammonium and calcium.

Determination of fluoride, chloride, bromide and sulfate in residual solvent using combustion digestion as sample preparation and subsequent anion chromatography with conductivity detection following sequential suppression. The analysis is significant for use in dividing waste products into non-halogenated and halogenated solvents.Keyword: pyrohydrolysis

This application describes the determination of fluoride, chloride, bromide and sulfur (as sulfate) in an ethanol standard solution with halo organic (4-halogen benzoic acids; F, Cl and Br) and sulfur organic compounds (3-(Cyclohexylamino)-1-propanesulfonic acid) by means of Metrohm Combustion Ion Chromatography with flame sensor and Inline Matrix Elimination.Keyword: pyrohydrolysis

Determination of a nonionic surfactant of the alkyl propylene oxide derivative type in commercial mixtures containing anionic surfactants.

Determination of chlorine in household bleaches.

Determination of sodium lauryl ether sulfate surfactants.

Weak, organic bases that are soluble in nonaqueous solvents (including nonpolar solvents) are determined in glacial acetic acid using titration with strong acids, e. g., anhydrous perchloric acid or trifluoromethanesulfonic acid. The endpoint of such titrations can be determined thermometrically, insofar as a suitable thermometric endpoint indicator exists. The exceptional suitability of isobutyl vinyl ether (IBVE) as indicator has been demonstrated.

Metal-organic compounds are commonly used in organic chemistry, for example as Grignard reagents or as strong bases (e.g., butyl lithium compounds). The knowledge of the exact content of reactive species allows to better plan the required amounts for reactions preventing the waste of material or too low yields.This Application Note describes the analysis of metal organics by thermometric titration using 2-butanol as titrant. Due to the strongly exothermic nature of the reaction between 2-butanol with metal-organic compounds, a fast and quantitative analysis of these substances is possible.

Lucigenin is one of the most often used chemiluminescent reagents and might be used for e.g., the indication of the presence of superoxide anion radicals.Lucigenin is rather expensive to buy, however, its synthesis only includes a two stage synthesis starting from acridanone. The first stage includes an Nmethylation, the second forms the lucigenin chloride, which is finally transformed into lucigenin nitrate. To check the purity of the synthesized lucigenin, ion measurement can be applied using a nitrate selective electrode. This is a fast and inexpensive method compared to competing methods such as ion chromatography.

The water content of methyl ethyl ketone peroxide is determined according to Karl Fischer using two-component reagents in order to prevent unwanted side reactions. (Separate solvent is used to ensure a high excess of sulphur dioxide and amine in the titration vessel.)

The water content of ammonium and potassium peroxodisulphate is determined according to Karl Fischer using two-component reagents. To prevent unwanted side reactions the determinations are carried out at -20 °C. Because the potassium salt is insoluble in the solvent, a high-frequency homogenizer is used to disintegrate the salt particles.

The water content of organic peroxides is determined according to Karl Fischer using two-component reagents. To prevent any unwanted side reactions, the determinations are carried out at -20 °C.

The water content of cyclopropyl methyl ketone is determined according to Karl Fischer by coulometric titration using special reagents for aldehydes and ketones.

This Application Note describes the determination of water content in pesticides using Karl Fischer titration.

The water content of 2-methyl-1,3-butadiene and 2,5-norbornadiene is determined according to Karl Fischer using a special solvent mixture to prevent unwanted side reactions.

The water content of acetophenone and benzophenone is determined according to Karl Fischer using special KF reagents for ketones/aldehydes to prevent unwanted side reactions.

The water content of piperidine and piperazine is determined according to Karl Fischer using a buffered solvent mixture.

The water content of 2-methyl-5-mercaptothiadiazole is determined according to Karl Fischer using a special solvent mixture to prevent unwanted side reactions.

Determination of acetate and methansulfonate in an organic salt using anion chromatography with direct conductivity detection.

Determination of carbonate in a solution of methyl-monoethanol-amine with anion chromatography with direct conductivity detection.

Determination of chloride, bromide, and iodide in alkaline combustion solutions using anion chromatography with direct conductivity detection.

Determination of pyrophosphate, tripolyphosphate, and trimetaphosphate using anion chromatography with direct conductivity detection.

Determination of fosetyl-aluminum (aluminum tris(o-ethylphosphate)) using anion chromatography with direct conductivity detection.

Determination of carbonate in washing powder using anion chromatography with direct conductivity detection.

Determination of borate and silicate in washing powder using anion chromatography with direct conductivity detection.

The purity of a recovered solvent (dichlormethane/methylene chloride) and two of its most important contaminants (methanol and water) are monitored with NIR spectroscopy.

Visible near-infrared (Vis-NIR) spectroscopy can be used as a fast and accurate analytical method for the quantification of different analytes and active ingredients in detergents, such as tetraacetylethylendiamin (TAED), sodium percarbonate (PCS), and enzymes. This Application Note shows how NIRS can be used for multi-constituent analyses in detergents in a single measurement.

Near-infrared spectroscopy (NIRS) was used as an analysis method for quality control of soap noodles. Quantitative models for the determination of Total Fatty Matter, Iodine Number, and C8–C14 were developed, enabling fast and reliable quality control.

This Application Note shows that visible near-infrared spectroscopy (Vis-NIRS) can be used for the quantification of five effective insecticide and herbicide components (Abamectin emulsifiable concentrate (EC), Emamectin EC, Cyhalothrin EC, Cypermethrin and Glyphosate) in pesticides. Vis-NIRS is an excellent alternative to conventional lab methods, saving both cost and time.

Determination of glycolic acid and monochloroacetic acid in cocoamidopropyl betaine using ion-exclusion chromatography with direct conductometric detection.

Arabinonic acid, glyceric acid, glycolic acid and formic acid can be determined in organic compounds using ion-exclusion chromatography with subsequent conductivity detection in accordance with inverse suppression. The Metrohm Suppressor Module in its lithium form is used for this purpose: This reduces background conductivity and ensures that the acids are present in their completely disassociated Li+ form. The suppressor is regenerated with lithium chloride.

Monoethylene glycol (MEG) is used to remove water from natural gas before further processing. Due to high temperatures applied, glycol degradation to glycolic, formic, and acetic acid may occur. These reactions are unwanted as the emerging acids are corrosive. The determination of the organic acids is achieved by ion-exclusion chromatography with conductivity detection after inverse suppression.

Glycol solutions act as antifreeze agents and are often used as such in motor vehicles. Due to the toxicity of (mono)ethylene glycol (MEG), use is being increasingly expanded to the non-toxic propylene glycol. This Application Note presents the separation and quantification of the two glycols. Separation is performed on the Metrosep Carb 2 - 250/4.0 column. Due to the absence of chromophores and the low conductivity of the glycols, pulsed amperometric detection (PAD) is used to facilitate determination.Key words: ethanediol, propanediol

This Process Application Note presents a method to accurately monitor low levels of moisture in tetrahydrofuran (THF) in «real-time» safely, reliably, and optimally with a 2060 The NIR Analyzer from Metrohm Process Analytics. Due to the hazardous and hygroscopic nature of THF, a single explosion-proof inline process analyzer is the preferred solution for industries to reduce chemical treatment, improve product quality, and increase profits.

The combination of 940 Professional IC Vario, 942 Extension Module Vario LQH and 941 Eluent Preparation Module enables process monitoring with the aid of ion chromatography. Assigned the designation ProfIC Vario 12 Anion, this combination is the anion variant of Metrohm Process IC. Intelligent preconcentration technology with matrix elimination is used for sample preparation. The use of an ELGA PURELAB® Flex 6 guarantees the supply of ultrapure water of the highest quality, particularly in cases of high numbers of samples.

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.

This application note presents the Orbital Raster Scan (ORS) technology from Metrohm Raman to overcome low resolution, poor sensitivity, and sample degradation while still interrogating a large sample area.

Signal-to-noise ratio, spectrograph design, resolution of MIRA handheld Raman analyzers.

Metrohm’s MIRA XTR handheld Raman spectrometer enables fast, reagent-free identification of phosphate species, enabling continuous monitoring of dynamic systems.

Raman spectroscopy with PLS modeling enables rapid, accurate, nondestructive quantification of the total phosphate content in solution with minimal sample preparation.

Low frequency Raman spectroscopy extends conventional Raman analysis by capturing vibrational modes down to 65 cm-1, enabling deeper insights into molecular structure, protein characterization, polymorph identification, and phase changes.

Determination of chloride, sulfite, and sulfate in a surfactant solution using anion chromatography with conductivity detection after chemical suppression.

Determination of phosphate and sulfate in a cleaning solution using anion chromatography with conductivity detection after chemical suppression.

Determination of traces of chloride in a technical product using anion chromatography with conductivity detection after chemical suppression.

Determination of phosphate and phosphite in poly(phosphonic acid) using anion chromatography with conductivity detection after chemical suppression and dialysis for sample preparation.

Determination of chloride, nitrate, and sulfate in sodium thiocyanate using anion chromatography with conductivity detection after chemical suppression.

Determination of chloride, nitrite, nitrate, phosphate, sulfate, trimeta-, and pyrophosphate in tripolyphosphate using anion chromatography with a high pressure gradient and conductivity detection after chemical suppression.

Determination of o-phosphate, pyrophosphate, and trimetaphosphate in sodium tripolyphosphate using anion chromatography with conductivity detection and chemical suppression.

Determination of bromoacetate, methanesulfonate, chloride, phosphate, and sulfate in an acidic cleaning solution using anion chromatography with conductivity detection and chemical suppression.

Determination of hexafluorophosphate in an ionic liquid BMIHFP (1-butyl-3-methylimidazolium hexafluorophosphate, >97%) using anion chromatography with conductivity detection after chemical suppression.

Determination of sulfate, phosphate, citrate, pyrophosphate, trimetaphosphate, and tripolyphosphate in a washing powder using anion chromatography with conductivity detection after chemical suppression.

Determination of traces of chloride in a quaternary ammonium hydroxide using anion chromatography with conductivity detection after chemical suppression and inline cation exchange to remove the matrix cations.

Determination of chloride, sulfite, sulfate, and thiosulfate in metam potassium (potassium N-methyldithiocarbamate) using anion chromatography with conductivity detection after chemical suppression.

Determination of sulfate in methanedisulfonic acid using anion chromatography with conductivity detection after sequential suppression.

Determination of molybdate in 2.5% NaCl using anion chromatography with conductivity detection after chemical suppression and inline matrix elimination by molybdate preconcentration after the first separation and subsequent reinjection.

Determination of chloride, nitrate, and sulfate in cobalt acetate solution using anion chromatography with conductivity detection after sequential suppression using Metrohm Inline Dilution.

Determination of fosetyl-aluminum in a formulation using anion chromatography with conductivity detection after sequential suppression.

Determination of phosphate, HEDP (etidronic acid), and pyrophosphate in a biocide sample using anion chromatography with conductivity detection after sequential suppression.

The high-capacity suppressor MSM-HC allows to run analyses with high eluent concentrations, e.g., sodium hydroxide eluents. The determination of anions in washing powder is a typical example where the high pH of NaOH is required for the separation of polyphosphates.

Ionic liquids, also denominated as «designer solvents», are organic salts that are liquid at low temperatures. They are powerful solvents, conduct the electric current, and are therefore used in many applications. Anions, in particular halogenides, are common byproducts in the manufacturing of ionic liquids. Therefore, their concentration has to be controlled.

Sulfamic acid is a reasonably strong acid, used in descaling agents and for cleaning of dairy and brewing equipment. Here, a chemical solution is analyzed for sulfamate, chloride, nitrite, nitrate, and sulfate. As the solution can also contain hydramine, sufficient separation from the ions of interest is required.

Determination of the cationic surfactant «cetrimide» in an antiseptic disinfectant by potentiometric titration with sodium dodecyl sulfate using the «Ionic Surfactant» electrode.

This application note shows a reliable way to determine the content of non-ionic surfactants in liquid cleaning solutions by potentiometric titration.

Determination of nonionic surfactants in compact washing powders by potentiometric titration with sodium tetraphenylborate using the NIO surfactant electrode.

Determination of perborate, percarbonate, or persulfate in washing powder by iodometric potentiometric titration using the Pt-Titrode.

Determination of free alkali in sodium hypochlorite by potentiometric titration with hydrochloric acid using a combined glass electrode.

Determination of the soap content of soap noodles by potentiometric titration with TEGO®trant A100 using the «Ionic Surfactant» electrode.

Determination of soaps and anionic surfactants in washing powder by potentiometric two-phase titration with TEGO®trant A100 using the «Surfactrode Resistant» electrode.

Determination of cationic surfactants in a household cleaner by potentiometric two-phase titration with sodium dodecylsulfate using the «Surfactrode Resistant» electrode.

This application note describes the determination of nonylphenol ethoxylate by potentiometric titration with sodium tetraphenylborate using the NIO surfactant electrode.

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.

Determination of lauryl ether sulfate (LAES) by potentiometric/turbidimetric titration with TEGO®trant A100 using the 610 nm Spectrode.

Tallow amine ethoxylates are toxic to aquatic life, and therefore their use is restricted. This Application Note explains an approach to determine these non-ionic surfactants potentiometrically.

This application note shows how coconut oil ethoxylates can be determined via potentiometric titration.

Inorganic sulfate is determined in secondary alklysulfonate (raw material) in accordance with DIN EN 14880 with the use of the Pb ISE.

Citrate is used in detergents as a water softener for the prevention of lime deposits. The citrate or citric acid content is therefore an important parameter for the quality control of detergents that can be determined conveniently and precisely using titration with copper sulfate.

Nitrilotriacetate (NTA) is a complexing agent that is used in detergents as a water softener. NTA forms complexes with metal ions such as Ca2+, Cu2+ and Fe3+ and thus prevents the formation of lime and its deposits. The NTA content is therefore an important parameter for the quality of detergents and is determined using back titration of an excess of copper nitrate.

Quaternary ammonium salts are the active ingredients in fabric softener and require accurate determination to assess the cost and the performance of the fabric softener. This Application Note describes the determination of diamidoamine-based quaternary ammonium salts by potentiometric titration.

Quaternary ammonium salts are the active ingredients in fabric softener and require accurate determination to assess the cost and the performance of the fabric softener. This Application Note describes the determination of dialkyl dimethyl quaternary ammonium salts by back titration.

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.

Anionic surfactants represent, by volume, the most important group of surfactants used in cleaning products. The potentiometric two-phase titration is a universal method for the accurate and fast determination of them. Using the Surfactrode Refill, the anionic surfactants are determined by potentiometric titration with hyamine as titrant.

The bromine index is an important parameter for the determination of aliphatic C=C double bonds in petroleum hydrocarbons. For the titration, a solvent mixture of glacial acetic acid, methanol, and dichloromethane is usually used.In this Application Note, the chlorinated solvent in the solvent mixture was replaced with toluene, resulting in a more environmentally beneficial method in comparison to ASTM D2710 and IP 299.

The bromine index is an important quality control parameter for the determination of aliphatic C=C double bonds in aromatic hydrocarbons and is thus a measure for the presence of aliphatic unsaturation in these materials. In situ generated bromine reacts with the aliphatic double bonds. When the titration is finished an excess of free bromine causes a sudden change in the measured potential thus indicating the equivalence point.

This Application Note shows the automatic pH adjustment of a mixture of acetonitrile, water and amine using a Metrohm titrator.

The amine value is an important parameter and quality indicator to determine in chemical processes and pharmaceuticals. This Application Note presents the nonaqueous perchloric acid titration of triethanolamine.

Determination of HEDPA, PBTC, and NTP using anion chromatography with UV/VIS detection after post column reaction (PCR).

Determination of cadmium and lead in herbicide powder containing 37% copper after digestion.

Determination of W(VI) in the organic phase after digestion

The concentration of nitrobenzene in aniline is determined by polarography in an ethanol / acetic acid electrolyte.

Enhance quality control in material and chemical production with NIRS. Fast, cost-effective, and no sample prep needed. Learn more in our eBook.

Near-infrared spectroscopy (NIRS) is a widely used analytical technique for qualitative and quantitative analysis of various products in research and industrial applications. Because of different reasons it might be necessary to transfer analytical methods from one NIR analyzer to another one. This white paper summarizes the workflow of such method transfer.

Quality control is impacted by multiple challenges, which can have an influence on the functioning of the QC lab. The present White Paper provides approaches, how to simplify the daily quality control using near-infrared spectroscopy combined with a dedicated smart software like Vision Air.

Analyzer systems monitoring product quality can offer substantial advantages when organized in a client-server network compared to the more traditional local installation. This white paper presents different client-server setups and their benefits. Security aspects that need to be considered are discussed based on the example of the client-server Vis-NIR (visible near-infrared) spectroscopy software Vision Air, widely used for quality control in the chemical, polymer, pharmaceutical, and petrochemical industry.

Underestimation of quality control (QC) processes is one of the major factors leading to internal and external product failure, which have been reported to cause a loss of turnover between 10–30%. As a result, many different norms are put in place to support manufacturers with their QC process. However, time to result and the associated costs for chemicals can be quite excessive, leading many companies to implement near-infrared spectroscopy (NIRS) in their QC process. This paper illustrates the potential of NIRS and displays cost saving potentials up to 90%.

With Hydranal™ NEXTGEN FA reagents, the water content in ketones can be determined quickly and reliably. Compared to other existing KF reagents for ketones on the market, the side reactions are measurably better suppressed.

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