Aplikácie

The FOS/TAC value is an important characteristic to assess the status of the fermenter before costly problems arise. The new Eco Titrator from Metrohm allows the determination of this quotient in a fast, cost-efficient, and precise way.

A measured amount of salt is titrated directly with a solution of 1 mol/L tetrasodium EDTA to thermometrically determined endpoints for Ca and Mg. Acetylacetone is added to alter the Ca and Mg EDTA stability constants for better endpoint sharpness.

Sulfate is precipitated as barium sulfate by reaction with an acidified barium chromate solution. The excess barium chromate is precipitated by basification with ammonia solution. Residual soluble chromate, equivalent to the sulfate content of the sample, is titrated with a solution of standard ferrous ion to a thermometrically determined endpoint.

A measured amount of acidic hydrometallurgical leach liquor is pH modified with a small amount of glacial acetic acid, and the Fe(III) content reduced to Fe(II) with iodide ion. The liberated iodine is titrated with standard thiosulfate solution to an exothermic endpoint. Thus, 1 mol Fe3+= 1 mol S2O32-.

Sulfate is precipitated by reaction with an acidified barium chromate solution. The excess barium chromate is precipitated by basification with ammonia solution. Residual soluble chromate equivalent to the sulfate content of the sample is titrated with a solution of standard ferrous ion to a thermometrically determined endpoint.

A routine method for the determination of copper is described. After dissolving the sample and adding a KI/KCNS solution, the released iodine is back-titrated with thiosulfate. The endpoint indication is potentiometric.

The Bulletin describes the determination of the following parameters in wine: pH value, total titratable acid, free sulfurous acid, total sulfurous acid as well as ascorbic acid (vitamin C) and other reductones.

A measured amount of acidic hydrometallurgical leach liquor is first treated with hydrogen peroxide to oxidize Fe(II) to Fe(III), then with potassium pyrophosphate solution to mask interference from Fe(III) and other metal ions. Ammonium acetate solution is then added as a pH modifier, before being titrated with standardized disodium dimethylglyoximate to an exothermic endpoint.

This Application Note describes the determination of the free and total hydroxide and aluminum oxide content in Bayer process and other aluminate liquors. The method is not subject to interference by carbonate ions. An aliquot of sodium aluminate liquor is titrated with potassium hydrogen carbonate solution to yield the free hydroxide ion content of the liquor.

The quality of a vinegar depends on various factors. Since the contents of the individual components vary widely even from bottle to bottle, it is impossible to give average values. This Bulletin describes the determination of the following parameters in vinegar: pH value, total titratable acid, volatile, and non-volatile acid, free mineral acid as well as free and total sulfurous acid.

After acid digestion, the sample solution is neutralized with sodium hydroxide to form sodium dihydrogen phosphate. An excess of lanthanum nitrate is added and the released nitric acid is then titrated with sodium hydroxide solution.NaH2PO4 + La(NO3)3 → LaPO4 + 2 HNO3 + NaNO3This determination method is suitable for higher phosphate concentrations.

A measured amount of milk is treated with trichloroacetic acid to coagulate milk solids and liberate calcium and magnesium as dissociated ion. The coagulated milk is filtered or centrifuged, and an aliquot of the clear serum is titrated with a standard solution of 1 mol/L tetra-sodium EDTA to thermometrically determined endpoints for Ca and Mg. Acetylacetone is added to alter the Ca- and Mg- EDTA stability constants for better endpoint sharpness.

A measured amount of acidic hydrometallurgical leach liquor is treated first with a complexing agent (sodium gluconate). It is then basified to ~pH 10.5 with a NH3 /NH4Cl buffer, prior to the addition of KCN solution to mask Fe(III). Caution! Do not add KCN to solutions of pH below 9! The Fe(III) is then reduced to Fe(II) by additon of ascorbic acid, prior to titrating the Mg content with standard Na4EDTA solution.

This Application Note describes the determination of total content of Ba, Ca, Mg, Pb and Zn in unused lubricating oil by means of the Optrode (610 nm). An excess of EDTA is first added to the metals. Afterwards, the excess EDTA is titrated back with magnesium chloride solution up to the end point of the indicator Eriochrome Black T.

This Bulletin describes the fully automated determination of uranium according to the method of Davies and Gray: Uranium(VI) is reduced in concentrated phosphoric acid solution with iron(II) to form Uranium(IV). With molybdenum as a catalyst, the excess iron(II) is oxidized with nitric acid. The nitrous acid that is formed is destroyed with sulfamic acid before uranium(IV) is titrated with a potassium dichromate solution in the presence of a vanadium catalyst.

This Bulletin describes analysis methods for determining the following parameters: pH value, total titratable acid, ash alkalinity, formol number, total sulfurous acid, chloride, sulfate, calcium, and magnesium. These methods are suitable for the analysis of jams, fruit and vegetable juices, and their concentrates.

This Bulletin describes the potentiometric determination of hydrogen sulfide, carbonyl sulfide, and mercaptans in gaseous and liquid products of the oil industry (natural gas, liquefied petroleum gas, used absorption solutions, distillate fuels, aviation gasoline, gasoline, kerosene, etc.). The samples are titrated with alcoholic silver nitrate solution using the Ag Titrode.

Compared to potentiometric titration, Raman spectroscopy is a rapid, accurate, and reliable secondary method for estimating the amine value (AV) of epoxy hardeners.

This Application Note highlights near-infrared spectroscopy as a faster, cost-effective alternative to KF titration for predicting water content in diesel fuel.

Determination of suppressor «Cupraspeed» in acid copper baths by dilution titration (DT) using cyclic voltammetric stripping (CVS).

Determination of suppressor «InPulse H6» in acid copper baths by dilution titration (DT) using cyclic voltammetric stripping (CVS).

Determination of suppressor «Cupracid BL-CT» in acid copper baths by dilution titration (DT) using cyclic voltammetric stripping (CVS).

Determination of suppressor «Solderon ST-200 Primary» in a tin bath by dilution titration (DT) using cyclic voltammetric stripping (CVS).

Determination of suppressor «Copper GleamTM 2001 Carrier» in acid copper baths by dilution titration (DT) using cyclic voltammetric stripping (CVS).

Determination of suppressor «MACuSpecTM PPR 100 Wetter» in acid copper baths by dilution titration (DT) using cyclic voltammetric stripping (CVS).

Determination of suppressor «MultiBondTM 100 Part A20» in an acid copper bath by dilution titration (DT) using cyclicvoltammetric stripping (CVS).

Determination of suppressor «Ronastan TP Additive» in a tin/lead bath by dilution titration (DT) using cyclic voltammetric stripping (CVS).

Determination of suppressor «Thru-Cup EVF-B» in acid copper baths by dilution titration (DT) using cyclic voltammetric stripping (CVS).

Determination of suppressor «Top Lucina α-M» in acid copper baths by dilution titration (DT) using cyclic voltammetric stripping (CVS).

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.

Fluoride content in drinking water can be determined quickly and conveniently with the help of potentiometric titration and the ion-selective fluoride electrode (F-ISE). The F-ISE is calibrated with suitable standard solutions before the measurement.

Near-infrared spectroscopy (NIRS) was used for quality control of skin creams. A model for the quantification of the water content was developed based on Karl Fischer titration (KF), enabling fast and reliable atline analysis and final product quality control.

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.

Polyols are widely used as polyurethane feedstocks, where tight quality control of parameters such as hydroxyl value, acid number, moisture, and viscosity is essential. Conventional titration methods are standardized but slow and costly due to hazardous chemicals and waste handling. Near-infrared spectroscopy (NIRS), recognized by ASTM for hydroxyl value determination, enables rapid, reagent-free, multiparameter analysis of polyols with significantly lower operating costs.

As an alternative to titration, ion chromatography (IC) with suppressed conductivity detection has been approved by USP as validated method to quantify chloride content in NaCl tablets for solution or oral use.

This bulletin contains two parts. The first part gives a short theoretical overview while more details are offered in the Metrohm Monograph Conductometry. The second, practice-oriented part deals with the following subjects:Conductivity measurements in general; Determination of the cell constant; Determination of the temperature coefficient; Conductivity measurement in water samples; TDS – Total Dissolved Solids; Conductometric titrations;

This Process Application Note deals with the online monitoring of calcium and sulfate in flue gas scrubbing solutions using titration. Other contaminants that can be measured are sulfite, chloride, and chlorine. Low concentrations of heavy metals such as cadmium, zinc, copper, and lead can be measured in the ppb/ppm range with the ADI 2045VA Process Analyzer using voltammetry.

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.

Coagulation and flocculation are an essential part of treating both drinking water and wastewater. Aluminum salts such as aluminum sulfate and polyaluminum chloride (PAC) are often used for this purpose. For the precise application and exact dosage of the flocculant, it is important to accurately determine its aluminum content. In this Application Note, the aluminum content is accurately and reliably analyzed based on ABNT NBR 11176 using the 859 Titrotherm equipped with a Thermoprobe HF and sodium fluoride as titrant.

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 details the determination of acid-neutralizing capacity (ANC) in several pharmaceutical samples in compliance with USP<301> standards.

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

The quantification of residual moisture in lyophilized pharmaceutical peptides is an important measure for quality control in the pharmaceutical industry. For development purposes, such measurements are necessary and routinely performed during stability studies and to optimize the freeze-drying process (lyophilization). Currently, Karl Fischer titration is widely used for moisture determination in routine analysis. However, this method is time consuming and destroys the sample during analysis. This Application Note shows that near-infrared spectroscopy (NIRS) is a fast, reagentless, non-destructive method to determine moisture content in lyophilized pharmaceutical products.

Moisture content is one of the most commonly measured properties of fertilizers. Globally, regulations for different fertilizers vary, but local legal limits ensure that the maximum amount of water must not be exceeded. Next to gravimetric methods, Karl Fischer titration is often used for accurate moisture determination.Compared to these methods, near-infrared spectroscopy (NIRS) offers unique advantages: it generates reliable results within seconds, and at the same time does not create chemical waste. This Application Note explains how NIRS can offer fast, reagent-free analysis of moisture content in various fertilizer products.

This Application Note describes the conductometric determination of the total base number in engine oil according to IP 400.

The planarity and smoothness of silicon wafers are fundamental to manufacture optimal semiconductor devices, and Chemical Mechanical Planarization (CMP) is the most common technology used to achieve ultra-flat surfaces. A slurry is used for this purpose, composed of deionized water, a colloidal silicon or alumina liquid dispersion, and hydrogen peroxide, which has to be constantly monitored at all times.Online monitoring of the CMP process is necessary to avoid chemical waste and enhance wafer production yields. Metrohm Process Analytics can measure not only the H2O2 concentration, but also pH, conductivity, and temperature using the multipurpose 2060 Process Analyzer.

This Application Bulletin describes the method of near-infrared spectroscopy in diffuse reflection for the purpose of determining residual moisture in a lyophilized pharmaceutical product. Numerous sample vials containing freeze-dried pharmaceuticals were spiked with varying amounts of water for calibration purposes. The resulting differences in the absorption wavelengths of the OH-oscillation were correlated with the water content determined by Karl Fischer titration using the algorithm of multiple linear regression (MLR).

Kjeldahl nitrogen is a typical titration application that follows digestion and ammonia distillation. The ASTM Standard D8001 now offers an alternative applying persulfate digestion followed by IC determination. No distillation is required. In addition, the method enables the determination of total nitrogen and total phosphorus. We show the results of control samples containing organic substances. As these substances are dissolved in ultrapure water, the nitrogen concentration found corresponds to Total Nitrogen and Kjeldahl Nitrogen.

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.

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.

Many refiners look at discounted opportunity crudes as a means to improve their margin spread. The varieties of these cheap crude oils on the market are growing in number, but they have hidden risks for the purchaser caused by factors such as high naphthenic acid and sulfur content. Sulfur compounds and naphthenic acids are among the substances that contribute to the corrosive nature of crude oils and petroleum products. This is why the risk of corrosion is increased when processing crude oils with high naphthenic acid and sulfur content. The refiner must balance the cost benefit versus the risk and the cost of corrosion control when processing these crudes. A reliable acid number determination is a crucial part of corrosion control. Guest authors Bert Thakkar, Bryce McGarvey, and Colette McGarvey of Imperial Oil and Larry Tucker and Lori Carey of Metrohm USA were involved in the development of the new ASTM Method D8045 for acid number determination. Here, they report on the method and how it came to be.

This Application Note explains how to use magnesium to standardize tetrasodium EDTA titrant.

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.

This application note shows the use of an ion-selective copper electrode to measure the indium concentration in an aqueous solution.

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.

The hydroxyl number is an important sum parameter for quantifying the presence of hydroxyl groups in a chemical substance. As a key quality parameter, it is regularly determined in various polymers like resins, paints, polyesterols, fats and solvents. Unlinke other standards, ASTM E1899 works pyridine-free and without refluxing at elevated temperatures for a longer time. It is performed at room temperature, requires only a small sample size, is applicable to extremely low hydroxyl numbers (<1 mg KOH/g sample) and can be performed fully automatically. This Application Note describes the potentiometric determination of the hydroxyl number in 1-octanol and polyethylene glycol according to ASTM E1899, EN 15168 and DIN 53240-3. Using the OMNIS DIS-Cover technique all sample preparation steps can be fully automated. Moreover, the use of an OMNIS Sample Robot allows parallel analysis of multiple samples. The average time per analysis for one sample is thus reduced from approximately 24 min to 12 min., increasing productivity in the laboratory considerably.

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.

Online mercaptan and H₂S monitoring with the 2060 TI Ex Proof Analyzer certified for Zone-1 and Zone-2 areas.

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.

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.

This poster presents a straightforward ion chromatographic determination of HF, HNO3, short-chain organic acids and H2SiF6 in etching bath samples. Standard ions such as fluoride, nitrate, acetate and sulfate are determined via suppressed conductivity detection while dissolved silicate is spectrophotometrically detected in the same run after downstream post-column reaction (PCR) as molybdosilicic acid. Analytical results of several commercial HF-HNO3-H2SiF6 mixtures obtained by ion chromatography (IC) and titration showed good agreement, which confirms the applicability of the presented «dual» detection IC method for controlling the composition of acidic texturing baths.

Potassium iodide (KI) is used to treat overactive thyroid and to protect the thyroid gland from the effects of radiation from inhaled or swallowed radioactive iodine. Currently, in the USP Potassium Iodide Monograph, iodide identification is performed by wet chemistry and assay by manual titration, which has a history of reduced precision and accuracy. As part of USP’s global monograph modernization initiative, an alternative selective and sensitive method was developed and validated – ion chromatography (IC). The proposed IC method can also be used for the identification test as an alternative to wet chemistry.

In an electroless plating bath, the consumed ingredients have to be regularly replenished to ensure an even layer of nickel-phosphorus alloy. This requires online monitoring of the active bath constituents. Parameters to be controlled are pH value (4.5–5.0) as well as nickel (NiSO4 < 10 g/L) and hypophosphite concentration (NaH2PO2: 1–12%). Other measurement options include sulfate, alkalinity, and organic additives (via CVS).

Pickling baths are used in the galvanic industry to clean steel surfaces and prevent corrosion through passivation. Maintaining specific Fe2+/Fe3+ and free acid/total acid ratios is vital to ensure the baths' optimal performance, which directly impacts the final product quality and reduces production costs by minimizing reagent consumption. This application presents a method to regularly monitor the acid and iron composition in pickling baths online by using a process analyzer from Metrohm Process Analytics.

Water hardness is often determined photometrically using two different indicators and while performing the determination at two different pH values. Additionally, the determination itself is subjective, as the color change is determined by the analyst and not by an analytical device.This application note introduces a more robust option to easily assess calcium, magnesium, and total hardness in water by using the Cu-ISE and two different titrants. Sample preparation is identical for both analyses and can therefore be automated without any issues.

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.

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.

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

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>.

NPK fertilizers are mainly comprised of three primary nutrients required for a healthy plant growth (nitrogen, phosphorous, potassium). They are available as liquid, or granular form, whereof the last is the most common used one. Knowing the quality and content of a fertilizer allows an optimal utilization for a planned culture and optimizing the amount of used fertilizer. This helps to reduce costs and to improve plant growth and with it, a better harvest follows.To assess potassium, several methods like flame photometry, titration, or ion measurement can be used. In this work, the potassium content is measured by standard addition which is a fast, inexpensive, and easy to use method.

Excessive silica concentrations in the boiler feed water can lead to deposits on turbine blades and must therefore be avoided. Silica analysis is carried out via differential photometry using a leading-edge technology thermostatic cuvette module for non-sample contact at the detector. Typical concentration ranges for silica are 0–50 ppb and 0–1 ppm or higher.

The saponification value evaluates edible oil quality by indicating the average molecular weight of fatty acids. Its titrimetric determination in canola and olive oil is described here.

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.).

Karl Fischer reagents contain buffer substances (usually imidazole) since the reaction constant is dependent on the pH value. A constant pH therefore ensures the most repeatable results. In 2015, imidazole was classified by European Union the as a CMR (carcinogenic, mutagenic or toxic) substance and the statement H360D was added, stating possible harm to fertility or a fetus. Meanwhile, other reagents free of imidazole are available for purchase. This Application Note summarizes test measurements with 34433 HYDRANAL™ NEXTGEN Coulomat AG-FI.

Fluoride is commonly used in dental products to help prevent tooth decay. When fluoride is present in high concentrations, these products are regulated by 21 CFR 355. Three fluoride compounds used in over the counter (OTC) anti‐cavity dental products are sodium fluoride, stannous fluoride and sodium monofluorophosphate (MFP). The assay of fluoride in these active ingredients and finished formulations are determined by manual titration, or by ion‐selective electrodes. As a part of USP’s global monograph modernization initiative, an alternative selective and sensitive method has been developed and validated – ion chromatography (IC). The proposed IC method can also be used for the identification test as an alternative to the wet chemistry method.

The fermentation of corn starch to produce ethanol is a complex biochemical process that requires monitoring of many different parameters (e.g., solids, pH, sugar profile, glycerol, lactic and acetic acid, and water and ethanol content). Traditional laboratory analysis using primary methods (e.g. Karl Fischer titration) takes about an hour to complete and is a limiting step for increasing plant capacity and efficiency. As a fast and non-destructive analytical technique, near-infrared spectroscopy (NIRS) can replace routine laboratory analysis, decreasing operating costs and increasing plant efficiency and capacity. This White Paper describes the capabilities of the modern analytical method near-infrared (NIR) spectroscopy for monitoring and improving the fermentation process of corn to ethanol.

The permanganate index (PMI) is a sum parameter that indicates the total load of oxidizable organic and inorganic matter in water. The substances concerned are mainly humic materials/acids that are primarily formed when dead organic material present in soil is further broken down and released into water sources. As it is an indicator of the water quality, testing of the PMI for drinking water is obligatory in many countries.For the determination, it is necessary to heat the stabilized water sample to 95 °C and higher for a stipulated time. Afterwards, the amount of permanganate that has remained after the reaction with the sample is determined titrimetrically. This sample preparation step requires considerable manual effort.In this Application Note, a fully automated procedure for the determination of the PMI according to GB/T 11892 is described, including all sample preparation steps. The gains in productivity because of a reduced manual workload are considerable.

Anodizing metal surfaces improves resistance against corrosion and wear. Etching baths can be monitored precisely online with the 2060 TI Process Analyzer or 2026 HD Titrolyzer.

This Process Application Note is dedicated to the online analysis of zinc, iron and sulfuric acid in several stages of the zinc production process. Additionally, traces of germanium, antimony, as well as several transition metals (e.g., Ni, Co, Cu, Cd) can be precisely determined (<50 µg/L) in the purification filtrates and reactor trains.

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

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%.

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.

Calcium carbonate has a wide applicability in the pharmaceutical industry as an excipient and also as an active ingredient, and in the food industry as a major dietary supplement. The U.S. Pharmacopoeia (USP) monographs for calcium and magnesium carbonates tablets as well as calcium carbonate and magnesia chewable tablets currently describe manual titration as the assay procedure for calcium and magnesium. The USP has embarked on a global initiative to modernize many of the existing monographs across all compendia. In response to this initiative, two alternative analytical methods were developed to determine the analytes calcium and magnesium. This Application Note presents ion chromatography (IC) procedures using conductivity detection that provide better accuracy and specificity and are suitable for the intended purpose. These validated IC methods (according to USP General Chapter <1225>) offer a significant improvement to the existing assays because they can simultaneously determine both analytes calcium and magnesium, saving both time and effort.

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 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.

Determination of cuprous ions in the presence of ferrous ions in electrochemical copper leaching solutions.

Lithium-ion batteries (LIBs) are the most common rechargeable options available today. Production of LIBs needs to follow stringent quality standards.

This Application Note describes an automated system with which the chloride content in bouillon can be determined. The high degree of automation (e.g., automatic addition of acid and titer determination) reduces errors to a minimum and ensures outstanding reproducibility.

Determination of the sulfate content of brines.

Standardization of 0.1 mol/L in propan-2-ol for use in applications for the determination of weakly acidic species in non-aqueous media.

Standardization of cetyl pyridinium chloride solutions for use as a cationic surfactant titrant in the determination ofanionic surfactants such as sodium lauryl ether sulfate.

Standardization of barium acetate titrant used in the determination of sulfate in phosphoric acid. The same procedure is applied if barium chloride is chosen as the titrant.

Determination of phosphoric and nitric acids in liquors from the Nitrophos fertilizer manufacturing process.

The water content of ointments is determined according to Karl Fischer. Because of their high water and fat content, the samples are prediluted with a 1:1 mixture of chloroform and methanol.

A potentiometric, nonaqueous method is described for analyzing nitrating acid using cyclohexylamine as titrant. Both sulfuric and nitric acid can be determined quantitatively.

Determination of the sulfate content of wet process phosphoric acid.

Determination of chloride in Bayer process liquor.

Determination of mixtures of sulfuric, phosphoric, and nitric acids. The procedure is suitable for automated analysis using an 814 Sample Processor.

The water content of moisturising creams is determined according to Karl Fischer. Because of their high water content, the samples are first mixed and prediluted with dry methanol.

The water content of sweet liquorice is determined according to Karl Fischer. To dissolve the sample, a mixture of methanol and formamide is used as solvent and a high-frequency homogenizer as stirring device.

The water content of spices is determined according to Karl Fischer. To release the water from the cells, a high-frequency homogenizer has to be used.

The water content in panthenol is determined according to Karl Fischer.

The present article addresses the theory, practical aspects and troubleshooting of potentiometry.

The water content of yoghurt powder is determined according to Karl Fischer. Because of the relatively high water and fat content, the sample is prediluted with a 1:1 mixture of chloroform and methanol.

The water content of flour is determined according to Karl Fischer. To shorten the analysis times and to obtain more precise results, the determinations are carried out at 50 °C.

The water content of ethylene dichloride is determined according to Karl Fischer. As the sample may contain free chlorine, which interferes with the determination, separate KF reagents have to be used.

The water content of smoked salmon and smoked trout is determined according to Karl Fischer.

The water content of potato chips is determined according to Karl Fischer using the oven method (140 °C).

The water content of bismuth subnitrate is determined according to Karl Fischer.

The water content of beta-caprolactam is determined according to Karl Fischer.

The water content of vinyl chloride is determined according to Karl Fischer.

The water content of margarine is determined according to Karl Fischer.

Large sample sizes can lead to subtraction of too high blank values. This Application Note describes the calculation of a relative blank and thus helps to improve the accuracy of the method.

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.

Determination of water in moist particulate solids such as cobalt oxyhydroxide.

Determination of moisture in lubricating oils with TEOF (triethyl orthoformate).

Determination of water in automotive lubricating oils.

Determination of sulfate and total acids in a nitrating mixture.

The water content of potassium chlorate is determined according to Karl Fischer using the oven method (300 °C).

The water content of melamine is determined according to Karl Fischer in a buffered solvent mixture at 50 °C.

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

This Application Note describes the determination of the water content in transformer oil using the oven technique.

Monitoring hydrogen peroxide content online in the HP-PO production process requires a rugged explosion-proof solution like the 2060 TI Ex Proof Process Analyzer.

In accordance with the European Pharmacopoeia, sodium sulfate is determined with the PB ISE.

This White Paper gives an overview of the energy-intensive nitrification process that converts ammonia into less harmful nitrogen compounds at wastewater treatment plants (WWTPs). It displays the results from a field test at a WWTP, showcasing the positive influence of single-method process analyzers on the efficiency of the nitrification process.

Determination of chloride in oil well drilling fluids.

Determination of total basicity of extractable organic compounds of acidic character in Bayer process refinery liquors.

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 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.

This Application Note describes the determination of the water content in gelatine using the oven technique.

This Application Note describes the fully automated complexometric determination of total iron in cement with a copper ion-selective electrode.

Determination of Total Acid Number (TAN) values in mineral oils and similar fluids.

Standardization of ~1mol/L tetrasodium EDTA solutions for thermometric complexometric analysis.

Determination of total halides (Cl- + Br- +I-) in seawater and similar brines. This procedure is suitable for the analysis of total halides in seawater contaminated with sodium aluminate solutions emanating from alumina refineries, and seawater which has been used for the neutralization of alumina refinery waste («red mud») slurries. Given the small concentration of bromine andiodine in seawater, the total halide content approximates the chloride concentration.

This application note describes the determination of the total sodium content in soy milk products. The methodology may also be applied to the determination of sodium in milk products from cows, goats and sheep. A standard addition technique is employed to permit the accurate and precise determination of sodium at relatively low levels.

Sodium can be determined thermometrically in cheese without sample preparation and addition of additives. A homogenizer is responsible for distribution and stirring. In addition to this application note, you can find more information on thermometric sodium determination in foods in our application video available on YouTube:https://youtu.be/lnCp9jBxoEs

The water content of lemongrass oil is determined according to Karl Fischer. To prevent unwanted side reactions, special KF reagents for aldehydes and ketones are used and the determination is carried out at 0 ... 4 °C.

Precise online monitoring of peracetic acid (PPA) for beverage bottling requires a reliable stainless steel process analyzer.

The present Application Note describes an automated system with which the acidity can be determined in a wide variety of juice samples. The high degree of automation (e.g., automated calibration and titer determination) reduces errors to a minimum and offers outstanding reproducibility.

In this Application Note, the determination of calcium in milk is shown with the copper ion-selective electrode which is less sensitive to contamination from proteins.

This Application Note describes the iodometric, bivoltametric determination of ascorbic acid in orange juice using the Double Pt-sheet electrode.

This application note describes the fast, accurate determination of cobalt with a copper ion-selective electrode (Cu ISE) and Cu-EDTA complex as an indicator.

Magnesium can be determined with the Cu ISE. A small amount of Cu-EDTA complex is used as an indicator, as the Cu ISE is not selective for magnesium itself.

Nickel can be determined with the Cu ISE. A small amount of Cu-EDTA complex is used as an indicator, as the Cu ISE is not selective for nickel itself.

White paper on monitoring corrosion and the benefits of online or inline chemical analysis over manual sampling and offline laboratory methods for corrosion monitoring. Online and inline process application solutions for corrosion prevention with related application notes for further information are presented.

This poster presents a highly reproducible procedure for the determination of the sodium contribution of acid-extractable organic species in Bayer process liquor. The precision of the method is estimated to be 0.2% RSD.

Determination of mixtures of phosphoric, nitric, and acetic acids used in etching aluminum in the manufacture of semiconductor devices.

Determination of tar acids in coal tar products. This procedure may also be applied to the determination of a range of weakly acidic organic compounds such as carboxylic acids, hydroxy acids, phenols, phenolic acids, keto-enols, imides, and aromatic nitro compounds.11 Vaughan, G. A. Thermometric and Enthalpimetric Titrimetry. Van Nostrand Reinhold Co. Ltd (1973)

The water content of animal fat extract is determined according to Karl Fischer.

The water content of color paste is determined according to Karl Fischer.

The quality of egg-based pasta is primarily determined by its egg content. Also of importance, however, is the water content, which influences the storage life of the product, as well as the degree of acidity which, in the case of high values, indicates undesirable acidification during processing or drying. A check of the chloride content shows whether salt has been added to the pasta.

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

Standardisation of sodium tetraphenylborate (NaTPB) solution for the determination of potassium and for nonionicsurfactants.

Determination of bromide and chloride in photographic developer solutions.

Determination of low content of HCl (around 10 ppm) in silicone oil.

Determination of sodium as chloride in ketchups, sauces and, similar food products.

Determination of calcium and magnesium in seawater. The method is suitable for determining the effect of caustic soda and alumina refinery aluminate solutions on the calcium and magnesium content of seawater.

Determination of free acid in sulfuric acid («acid shot») solutions employed in the removal of silicate scale in heat exchangers. This method is suitable for acid shot solutions where the silicic acid content is so high that the solutions have gelled.

This Application Note describes the determination of aluminum ion down to approximately 0.5 g/L in acidic solutions containing ferric, ferrous, and other ions whose hydroxides do not dissolve in strongly basic solutions.

The water content of explosive pellets is determined according to Karl Fischer after extraction with methanol.

The water content of aniline is determined according to Karl Fischer in buffered solvent.

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.

This Application Note describes an automated system with which the chloride content in various water samples can be determined. The high degree of automation (e.g., automated addition of acid and titer determination) reduces errors to a minimum and ensures outstanding reproducibility.

Manganese is determined as Mn(II) in aqueous solutions at pH 10 with Eriochrome Black T as indicator. Ascorbic acid is added to ensure that manganese is present in its bivalent form. The precipitation of water-insoluble manganese hydroxide is prevented by adding triethanolamine (TEA). The Optrode is used for detection at a wavelength of 610 nm.

Commercially available fuels are complex mixtures of hundreds of different hydrocarbons. For the calibration of the test engines or advanced experimental and computational research they are modeled by means of multicomponent surrogate mixtures that adequately represent the desired physical and chemical characteristics. By definition, every octane and cetane number corresponds to a specific mixing ratio of primary reference fuels (PRFs). Based on this information, the tiamoTM controlled automatic dosing device prepares the surrogate mixtures. The setup drastically minimizes time-consuming and error-prone manual preparation steps and the contact with hazardous solvents. Additionally, precise and accurate results are displayed on customizable reports that fully comply with all current GLP and GMP requirements.

Determination of free acid in solutions containing metal ions, particularly Fe(III).

Determination of phosphate content in an acid etching bath.

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

Determination of the water content of liquid ammonia according to Karl Fischer after absorption of the water in ethylene glycol.

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

This Application Note describes the fully automated complexometric determination of barium in aqueous solutions with a copper ion-selective electrode.

This application note describes the analysis of cadmium in aqueous solution using a copper ion-selective electrode with Cu-EDTA complex used as an indicator.

This Application Note describes the automated complexometric determination of copper with the Cu ISE.

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.

Metformin is one the most commonly used drugs for diabetes type 2 belonging to the group of biguanides. This Application Note describes the determination of metformin hydrochloride assay according to USP using acetic anhydride as solvent.

Determination of acetic anhydride in the presence of acetic acid in acylation mixtures.

Determination of sodium lauryl ether sulfate surfactants.

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

Determination of free acid in copper refining solutions.

Determination of calcium and magnesium in process solutions.

Determination of sodium hypophosphite in electroless plating solutions.

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

Determination of the total acids concentration in mixtures of nitric-hydrofluoric acid intended for etching silicon substrates.

The water content of lime is determined according to Karl Fischer using the oven method (150 °C).

Determination of Na, P, and [Na]/[P] in precursor solutions and solids in the manufacture of sodium tripolyphosphate.

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 poster describes the water determination in pharmaceuticals using the Karl Fischer oven technique.

Determination of chlorine in household bleaches.

Automated determination of the H2SiF6 and HF contents of industrial grade hexafluorosilicic acid.

A high throughput automated system was developed to determine pH of culture media using a pH module equipped with an external flow cell. A custom septum-piercing, vented needle was developed to accommodate the shape and size of the customer sample vials. For this application, both accurate and precise pH measurements were required. The data presented in this document was collected by a customer as a part of their validation process and was provided for use with their consent.

Determination of ferrous ions in heat exchanger and vessel acid wash solutions, for measuring the effectiveness of acid inhibitors used in the solutions. Depending on the condition of the sample, the lower practical limit for the determination will vary from approximately 20-100mg/Kg Fe2+. Samples with high silicic acid contents require relatively large amounts of dilution water to render them mobile, and this limits the aliquot size and hence the amount of Fe2+ which can be analyzed.

Determination of chromium in leather waste solutions in the range between 1000 and 30,000 ppm.

This Application Note describes a method for the determination of causticizer, carbonate and aluminum oxide in used Bayer process liquors. The method is based on processes that were developed by Watts-Utley and VanDalen-Ward.

Corrosion in the water-steam circuit of power plants leads to shorter lifetimes of most metal components and potentially dangerous situations. Flow Accelerated Corrosion (FAC) is a specific case, leading to thinned pipes and elevated Fe concentrations in the circuit. Additionally, metal transport issues such as with Cu from copper heat exchangers can lead to deposition on the high pressure turbine blades, decreasing their efficiency. Current methods can monitor but not prevent these issues, and analysis times are extremely long (up to three weeks). In combination with the power plant’s Distributed Control System (DCS), online monitoring of Fe and Cu with the 2060 Process Analyzer from Metrohm Process Analytics ensures that corrosion can be controlled before it affects the power plant efficiency, ultimately decreasing downtime and lowering maintenance costs. Results are offered within 20 minutes, allowing fast adjustments to the water-steam circuit to protect company assets.

This Application Note describes the fully automated complexometric determination of zinc(II) in aqueous solutions with a copper ion-selective electrode.

Wine sometimes contains heavy metals which can be precipitated out by the addition of potassium ferrocyanide. Generally, these are quantities of iron ranging between 1 and 5 mg, and exceptionally up to 9 mg Fe/L. Zinc, copper, and lead – in descending order of content – may also be present. To estimate the quantity of potassium ferrocyanide necessary for the «décassage of the wine», only very complicated and relatively inaccurate methods have been described until now.This Bulletin permits accurate results to be obtained easily with a simple instrumentation. The results are available in a short time.

This Application Bulletin describes the determination of water in non-explosive and non-flammable gaseous samples using the coulometric Karl Fischer method. This method is ideal for very low water contents.

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

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%.