The content of organic matter, limestone, silt, clay, and sand, along with pH value and exchangeable calcium and magnesium in soil can be determined in seconds with NIRS.

This study shows how NIR spectroscopy simultaneously measures capsaicin content, Scoville Heat Units, water activity, ASTA color, and ash content in paprika powder samples.

NIR spectroscopy can measure several honey quality parameters simultaneously in just a few seconds without any sample preparation as shown in this Application Note.

This Application Note shows how near-infrared spectroscopy is used for fast, chemical-free multiparameter quality control of fabric softeners and laundry perfumes.

NIR spectroscopy is an alternative method for olive pomace fat analysis. Unlike other conventional methods, NIRS requires no sample preparation nor chemical solvents.

NIR spectroscopy measures ice cream quality parameters like total solids, fat content, lactose, protein percentage, sucrose content, and calories in seconds.

Near-infrared spectroscopy (NIRS) can simultaneously determine different quality parameters in deodorants like viscosity, pH, density, and aluminum content.

NIRS simultaneously measures important quality parameters in whey permeate (i.e., ash, phosphate, lactose, protein, pH, and moisture) without any sample preparation.

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

Determination of lauric acid, myristic acid, palmitic acid, and stearic acid using ion-pair chromatography with direct conductivity detection.

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

Determination of citrate and acetate in isotonic solutions using ion-exclusion chromatography with direct conductivity detection.

Determination of citric acid and ascorbic acid in vitamin tablets using ion-exclusion chromatography with direct conductivity detection.

Determination of citric acid and tartaric acid in fruit salt using ion-exclusion chromatography with direct conductivity detection.

Determination of organic acids and phosphate using ion-exclusion chromatography with direct conductivity detection.

Determination of gluconic acid and glycolic acid using ion-exclusion chromatography with direct conductivity detection.

Determination of citrate and saccharin in a nickel plating bath using ion-exclusion chromatography with direct conductivity detection.

Determination of gluconate and salicylate in a zinc plating bath using ion-exclusion chromatography with direct conductivity detection.

Determination of lactate, formate, and acetate in a cataphoretic paint bath using ion-exclusion chromatography with direct conductivity detection.

Determination of citrate, fluoride, lactate, and acetate in a plating bath using ion-exclusion chromatography with direct conductivity detection.

Determination of formate, acetate, propionate, butyrate, valerate, and capronate in an aqueous absorption solution using ion-exclusion chromatography with conductivity detection after chemical suppression.

Determination of lactate, formate, acetate, propionate, butyrate, isobutyrate, valerate,and isovalerate in a standard solution using ion-exclusion chromatography with conductivity detection after chemical suppression.

Determination of glycolic acid, formic acid, acetic acid and carbonic acid in a scrubber solution using ion-exclusion chromatography with conductivity detection after chemical suppression.

Determination of boric acid and acetic acid in process water using ion-exclusion chromatography with conductivity detection after chemical suppression.

Determination of glycolic acid, formic acid, glutaric acid, acetic acid, propionic acid, and butyric acid in a standard solution using ion-exclusion chromatography with suppressed and non-suppressed conductivity detection.

Determination of citric acid and lactic acid in an electroplating bath using ion-exclusion chromatography with conductivity detection.

Determination of glycolic acid, formic acid, glutaric acid, acetic acid, propionic acid, and butyric acid in paper industry process water using ion-exclusion chromatography with suppressed conductivity detection.

Determination of acetic, propionic, isobutyric, butyric, isovaleric, valeric, and caproic acid in potato juice using ion-exclusion chromatography with suppressed conductivity detection.

Determination of carbonate in an aqueous ammonia solution using ion-exclusion chromatography with suppressed conductivity detection.

Determination of citrate, ascorbate, and acetate in a food additive using ion-exclusion chromatography with suppressed conductivity detection.

Determination of sorbate and benzoate in a functional drink using ion-exclusion chromatography with suppressed conductivity detection.

Determination of L-lactide, citrate, and lactate in an acetone solution using ion-exclusion chromatography with direct conductivity detection.

Determination of citrate, succinate, lactate, β-hydroxybutyrate, and acetate in dry albumin powder using ion-exclusion chromatography with suppressed conductivity detection and dialysis for inline sample preparation.

Determination of citrate, ascorbate, and acetate in photographic developer solution using ion-exclusion chromatography with suppressed conductivity detection.

Determination of fumarate, lactate, formate, and propionate in animal food using ion-exclusion chromatography with suppressed conductivity detection.

Determination of carbonate in tap water using ion-exclusion chromatography with suppressed conductivity detection.

Determination of carbonate in sparkling water using ion-exclusion chromatography with suppressed conductivity detection.

Determination of malate and ascorbate in orange juice using ion-exclusion chromatography with suppressed conductivity detection and inline dialysis for sample preparation.

Determination of acetate and formate in an amine solution using anion chromatography with conductivity detection after suppression.

Determination of formate, acetate, propionate, isobutyrate, butyrate, isovalerate, valerate, and capronate added to tap water using anion chromatography with conductivity detection after suppression. The MCS is placed upstream of the chemical suppressor to remove interfering CO2.

Determination of citric, malic, quinic, succinic, lactic, formic, and acetic acid in roasted coffee using anion chromatography with conductivity detection after suppression.

Determination of sulfite, nitrite, nitrate, sulfate, imidodisulfonate, and peroxodisulfate using ion-pair chromatography with conductivity detection after suppression.

Determination of formate, acetate, propionate, isobutyrate, butyrate, isovaleriate, valeriate, and capronate using ion-exclusion chromatography with suppressed conductivity detection after inline dialysis.

Determination of borate in seawater using ion-exclusion chromatography with suppressed conductivity detection after inline matrix elimination.

Evidence of maleic acid in Asian foodstuffs led to the recall of many starchy foods because long-term consumption of maleic acid can cause kidney problems. Cyclic kojic acid is however approved in Asia, both as a bleaching additive in foodstuffs and as a preservative in cosmetics. This Note describes their simultaneous determination in a single analysis.

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.

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

The human daily intake of boron from food and beverages is approximately 2 mg. This is far below any toxic level. Some plants, however, are extremely sensitive to boron concentrations above 1 mg/L, e.g., strawberries, blackberries. As seawater contains 4 to 5.5 mg/L of boron, desalination is required to remove surplus boron besides other ions. This application shows the determination of boron (as borate) by ion-exclusion chromatography with conductivity detection after inverse suppression. The method has been optimized to get a sufficient fluoride/borate separation.

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.

Acidic gas sweetening solvents are used to remove acid gases such as H2S and CO2 from streams. Typically, amines are applied as alkaline components in these solvents. The determination of organic acids (glycolic, acetic, formic, propionic, and butyric acid) is achieved by ion-exclusion chromatography with conductivity detection after inverse suppression.

Sorbic acid and benzoic acid and their salts are used as food preservatives (E200, E201, E201, E203 and E210, E211, E212, E213 respectively). The content of such preservatives in flavored bottled water may easily be analyzed by ion exclusion chromatography. This method determines the concentration of the respective acid and does not allow differentiating between the counter cations. The determination of sorbic acids and benzoic acid is achieved by conductivity detection after inverse suppression.

Separation of polysaccharides with increasing numbers of inulin units using gradient elution and pulsed amperometric detection.

Determination of sucrose, glucose, and sucralose in a low-calorie sweetener using ion-exclusion chromatography with pulsed amperometric detection after post-column addition of sodium hydroxide.

Determination of polysaccharides (n glucose units) in potato starch using pulsed amperometric detection and a high-pressure gradient.

Determination of polysaccharides (n glucose units) in a plant extract using pulsed amperometric detection and a high-pressure gradient.

Determination of phenol, m-cresol, 2,6-dimethylphenol, and 2,3,6-trimethylphenol in tap water using amperometric detection and a glassy carbon electrode.

Determination of carbohydrates on the column Hamilton RCX-30 - 250/4.6 using pulsed amperometric detection.

Determination of carbohydrates on the column Hamilton RCX-30 - 150/4.6 using pulsed amperometric detection.

Nutritionally, banana fruit is a good source of mineral elements and vitamins A and C. Bananas begin the ripening process as soon as they are harvested, when they contain approximately 20-25% starch and 1% sugar. When the bananas turn yellow with some brown spots, they are fully ripened, and the ratio is completely reversed.

The determination of sugar and sugar alcohols is very important for food analysis. The Dose-in Gradient system extends the gradient capability of the standard IC system. The isocratic system is expanded to form a binary gradient system with just one 800 Dosino and one T-piece.

Inulin is a mixture of many fructose molecules. Inulin is increasingly being used in food production in recent times. This Application Note describes the determination of the inulin content in cakes. Correct analysis requires knowing which type of inulin is present, because the total number of fructose units varies. In this task, for example, the F8 peak (eight fructose units) was quantified.

Stevia is a plant of the Compositae family, the leaves of which can be used as a sweetener. In order for it to be used in the food sector, the purity of the steviol glycosides contained in the Stevia must be monitored. Utilization of the flexIPAD potential profile yields a greater sensitivity than standard PAD. The separation is accomplished on an RP column. Post-column addition of sodium hydroxide enables amperometric detection.

The determination of cyanide and sulfide in the trace range requires an alkali eluent and amperometric detection. This Application Note describes a new column/eluent combination for optimized separation. The combination consists of the Metrosep A Supp 10 - 100/2.0 Microbore Column and a sodium hydroxide eluent that contains traces of EDTA for the complexation of the transition metals. This yields a better peak shape and detection limits below 0.05 µg/L.

Sulfide and cyanide are toxic anions. Their trace determination in any kind of water samples, especially in wastewater, is requied for safety reasons. However, metal traces present in the eluent can mask target anions due to complexation. The addition of a stronger complexing agent to the eluent mask these metal cations enabling interference free determaination. This application is mainly used for the analysis of cyanide and/or sulfide in water. However, it also fulfills the requirements of ASTM D2036 for the determination of total, amenable, weak acid dissociable cyanides. The determination of cyanide and sulfide require an alkaline eluent and amperometric detection. This Application Note describes a new column/eluent combination for optimized separation. The combination consists of the Metrosep A Supp 10 - 100/4.0 column and a sodium hydroxide eluent containing a trace of EDTA for transition metal complexation. This yields in better peak shape and detection limits below 0.1 μg/L.

Traditionally, catecholamines are separated using reversed-phase chromatography followed by amperometric detection. This Application Note describes the determination of catecholamines in an emergency medication for life-threatening allergic reactions.

As a result of the private burning of wood, concentrations of levoglucosan, mannosan, and galactosan in the air are usually increased during the winter months. On the other hand, one can expect a greater contribution of sugar components from biogenic sources during the summer months. An optimum separation and sensitivity of the saccharide markers that accumulate on air filters can be achieved on the Metrosep Carb 2 - 150/4.0 column with subsequent pulsed amperometric detection.

Lactose intolerance means that lactose cannot be digested. Lactose is contained in milk and milk products. "Lactose-free milk" is analyzed following Inline Dialysis. No lactose was detected in the milk sample investigated. The chromatogram of the spiked sample corresponds to the limit value of 100 mg/L that applies for lactose-free milk. The separation is performed on the Metrosep Carb 2 - 150/4.0 column.

Polydextrose is a low-calorie, synthetic polymer made of glucose. It is a recognized additive for foodstuffs. Hot water is used to extract the polydextrose from the foodstuff, after which it is centrifuged. Subsequent fermentation removes maltooligomers and fructans. Afterwards, the polydextrose is quantified using anion-exchange chromatography with pulsed amperometric detection.

Scrubber solutions for scrubbing flue gas often contain amines for absorbing acid gases, e.g., sulfur dioxide (SO2). 1-(2-hydroxyethyl)piperazine and 1,4- Bis(2-hydroxyethyl)piperazine from gas scrubber solutions are separated in the Metrosep Carb 2 - 150/4.0 column and then determined using pulsed amperometric detection.

Ion chromatographic determination of sulfide in wastewater is performed using amperometric detection and an alkali eluent to ensure the stability of the sulfide. Measurements are performed in single-potential or direct current (DC) amperometric mode. It is the best-known and most sensitive amperometric measuring method and also provides, in addition to a high selectivity, a large selection of working electrodes.Sulfide determination is performed on a Metrosep A Supp 10 - 100/4.0 type column; a silver electrode is used as the working electrode.

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

EU Regulation 1169/2011 defines rules for nutrition declaration on foodstuffs. The objective is to provide food information to the general public and to label food ingredients that are hazardous to health when consumed in larger quantities. This Application Note describes the determination of four sugars in honey.

The separation of sugar and sugar alcohols in beverages is performed on a Metrosep Carb 2 - 150/4.0 type column using sensitive pulsed amperometric detection as the detection method. The method is explained exemplarily on an apple beverage.

The lactulose/rhamnose (L/R) intestinal permeability test is used for the diagnosis of dysfunctional intestinal permeabilities. This test comprises the determination of mannitol, rhamnose, lactose and lactulose in addition to the usual blood sugars, e.g. glucose, galactose and saccharose. This Application Note presents the analysis of a blood plasma sample enriched with the four sugars mentioned above.Key word: leaky gut syndrome

A low-pressure gradient enables the separation of sugar acids strongly retained on the column and sugars within an appropriate analysis time. The saccharides are separated on a column of the Metrosep Carb 2 - 250/4.0 type with subsequent pulsed amperometric detection (PAD). Galactose and arabinose are not completely separated under the selected conditions.

This Application Note describes the separation of inositol, mannitol, glucose, xylose, fructose, lactose, sucrose and cellobiose on a column of the Metrosep Carb 2 - 150/4.0 type with subsequent pulsed amperometric detection (PAD).

Sucralose is an artificial, non-nutritive sweetener that is approximately 600 times sweeter than saccharose. Sucralose is used in low-calorie refreshments such as soft drinks. Sucralose lends itself readily to determination there using ion-exclusion chromatography. A post-column addition of NaOH is required prior to pulsed amperometric detection.Keywords: E 965

Polyols and sugars in soaps enhance the stability and the size of air bubbles and foam. In addition to the polyol glycerin, sugar alcohols and sugars are often added to soaps. The determination of sorbitol and saccharose in a transparent soap takes place on a column of the Metrosep Carb 2 - 150/4.0 type with subsequent pulsed amperometric detection (PAD).

Biodiesel or green diesel is manufactured from fats and vegetable oils through ester interchange of the triglycerides they contain, during which glycerin accumulates as byproducts in both free and bonded forms. These accelerate fuel ageing and lead to deposits and clogged filters, which is why maximum permissible highest concentrations have been established (in the US in ASTM D6751 and in the EU in EN 14214).The two specifications prescribe the ion chromatography determination of free and bonded glycerin. This Note describes the determination with the aid of the Metrosep Carb 2 - 150/4.0 column in accordance with ASTM D7591.

As a result of the private burning of wood, concentrations of levoglucosan, mannosan and galactosan in the air are usually increased during the winter months. By contrast, a greater contribution of sugar components originating from biogenic sources can be anticipated in the summer months. Optimum separation and sensitivity of the saccharide markers that collect on air filters are achieved on the Metrosep Carb 2 - 150/2.0 column with subsequent pulsed amperometric detection.

EU Regulation 1169/2011 defines rules for nutrition declaration on foodstuffs. The objective is to provide food information to the general public and to label food ingredients that are hazardous to health when consumed in larger quantities. This Application Note describes the determination of three sugars in apple juice with the aid of the Metrosep Carb 2 - 150/2.0 column.

EU Regulation 1169/2011 defines rules for nutrition declaration on foodstuffs. The objective is to provide food information to the general public and to label food ingredients that are hazardous to health when consumed in larger quantities. This Application Note describes the determination of fruit yogurt with the aid of the Metrosep Carb 2 - 150/2.0 column.

Besides the typical sugar components, orange juice contains inositol. This sugar alcohol serves as an important signaling and messenger molecule. This Application Note shows the determination of inositol besides glucose, fructose, and sucrose in orange juice on a Metrosep Carb 2 - 150/4.0 column with pulsed amperometric detection (PAD).

This Application Note shows the determination of glucose and galactose in a 2% solution of lactose. The separation is achieved on a Hamilton RCX-30 - 250/4.6 applying pulsed amperometric detection (PAD) at a gold electrode. Instrument control, data acquisition, and data handling is done by Empower 3.0 using the Metrohm IC Driver 2.0 for Empower.

Mono- and disaccharides, often just called sugars, are constituents in many food products. They need to be quantified for declaration reasons. A flow gradient – on a microbore Metrosep Carb 2 - 250/4.0 column – ensures the separation of the monosaccharides while the disaccharides still elute before 50 min.

Maltodextrin is a polysaccharide consisting of glucose units. Maltodextrins are classified as dextrose equivalents (DE, with DE = 3–20). This application shows the determination of glucose (DE = 1), maltose (DE = 2) till maltoheptaose (DE = 7). The separation is achieved on a Metrosep Carb 2 - 250/4.0 column with subsequent pulsed amperometric detection (PAD).

Propylene glycol, also called propane-1,2-diol, is a humectant and applied in topical solutions to increase the solubility of the active pharmaceutical ingredient (API) or the ability to penetrate the skin. In this application, propylene glycol is determined in a placebo and two topical solutions containing diclofenac as the API. The separation is achieved on a Hamilton RCX-30-250/4.0 column with subsequent pulsed amperometric detection (PAD).

The separation of lactose, lactobionic acid, sialic acid*, 6’-sialyllactose, and 3’-sialyllactose is shown as a proof of concept for the control of these components in fermentation process for a pharmaceutical product. The acceptance criterion of a minimum resolution of the peaks (< 1.3) is reached. The separation is achieved on a Metrosep Carb 2 - 250/4.0 column with subsequent pulsed amperometric detection.

Cooked Italian pasta consists of about 30% carbohydrates, mainly starch. Sugars are water soluble and therefore most of them are extracted into the cooking water. This application identifies and quantifies the extractable sugars after water extraction of pasta at 60 °C.

Gentamicin is an aminoglycoside antibiotic and is composed of a number of related gentamicins. It is applied for several types of infections. For the determination of the major components, USP asks for chromatographic separation with pulsed amperometric detection using a gold working electrode. A post-column addition of NaOH is performed prior to the detection.

The Metrohm IC Driver for OpenLab CDS opens ion chromatography to the world of HPLC, running under OpenLab CDS. In this application, a soft drink is analyzed for sugars and sugar alcohol content applying pulsed amperometric detection.

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

Cyanide in wastewater is an important parameter to measure for health requirements. Free, weakly complexed, and strongly complexed cyanide can be differentiated. Direct measurement in the wastewater is not feasible due to the matrix itself. Therefore, total cyanide is determined after acidification of the sample, which releases all cyanide from complexes, and subsequent distillation and absorption of cyanide in an alkaline solution. Amperometric detection is applied using a gold working electrode. This electrode is advantageous over the silver electrode due to less contamination issues and better long-term stability.

Beer wort is the liquid in which malt starch is converted enzymatically into sugars and is additionally flavored and preserved with hops. The most important sugars for beer brewing are maltose and maltotriose, which will be fermented into alcohol by the added brewing yeast. The composition of carbohydrates in wort is determined on a Metrosep Carb 2 - 250/4.0 column applying a Dose-in gradient to optimize resolution and duration of the analysis.

Iodine is an essential mineral for human health, where it is necessary for e.g., the production of thyroid hormones. The presented method describes the determination of free iodide in milk samples using Metrohm Low Volume Inline Dialysis for automated sample preparation prior to injection into an ion chromatograph (IC) and subsequent amperometric detection in direct current (DC) mode.

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

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

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

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

This 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.

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

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

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.

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.

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 the cumene process, phenol and acetone are produced from benzene and propylene. For a successful process control, it is crucial to monitor the sulfuric acid concentration, which impacts the acid-catalyzed cleavage of cumene hydroperoxide to yield phenol and acetone. This Process Application Note describes the online analysis of sulfuric acid using titration. In such hazardous environments, the analyzer can be ex-proof or located in an ex-proof shelter.

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.

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

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

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).

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.

Automated online analysis with the 2060 TI Ex Proof Process Analyzer facilitates constant monitoring of the crude oil desalting process according to ASTM D3230.

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.

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.

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.

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.

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

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

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

The chemicals used in the manufacture of semiconductors must exhibit an exceptional purity, because even traces of contaminants have a negative effect on electrical properties. For the manufacture of printed circuit boards, the light-sensitive photoresist applied to the substrate (wafer) is exposed to light at defined areas with the aid of a photo template and then developed in a chemical reaction. The developer contains 2.38 to 2.62% tetramethylammonium hydroxide (TMAH) and ensures that the exposed areas can be readily separated from the substrate. The monitoring of the TMAH concentration in the developer solution takes place with a process analyzer from Metrohm Applikon that is configured specially for titration. In addition to this, the analyzer helps with the mixing of the TMAH solutions.

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

Chromium is extracted from chromite ore and is an important part in the production of stainless steel. Chromium is mainly divalent, trivalent and hexavalent in its compounds. In contrast to chromium(III), which is an important trace element and one that is only sparingly soluble in water, hexavalent chromium is extremely toxic and very water-soluble. Cr(VI) is furthermore an important raw material for industry. It must be determined rapidly and precisely in the lower µg/L range in wastewater. Metrohm Applikon offers an array of process analyzers for the analysis of wastewater streams which determine chromium precisely and reproducibly using photometry.

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.

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.

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

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

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.).

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

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.

Phosphorus removal is essential in waste water treatment plants to ensure the environmental balance is not upset by discharged effluent. In the treatment facility it is important to know the bioavailable o-phosphate phosphorus (o-PO4-P) concentration in the influent stream either to feed bacteria or to calculate the amount of reagents needed for chemical treatment. For environmental compliance monitoring purposes, treated effluent is monitored for TP – the sum of all insoluble and dissolved phosphates present. With the Metrohm Process Analytics 2035 TP Analyzer (complete with integrated compact digestion cuvette photometer module), you can keep track of both o-PO4-P and TP according to DIN EN ISO 6878:2004-09 around the clock.

Thermal power plants require enormous amounts of water, using high purity steam at high pressure to rotate turbines. A separate cooling water circuit is implemented, which helps to form a vacuum when the steam condenses after the turbines. Maintaining this vacuum with optimal condensation parameters is critical for the power plant efficiency. The copper condensers are susceptible to corrosion by ammonia, leading to an upper limit of 2 mg/L NH3 set by EPRI in cooling water. Small cracks in the condenser combined with the large pressure differential between the steam circuit and the cooling water circuit will contaminate the high purity water in the boiler, causing major problems and necessitating a shutdown for plant maintenance. Monitoring NH3 online in cooling water with a process analyzer can signal early problems in a plant before significant intermediation is necessary.

Polyurethanes are a class of synthetic polymers formed by reacting liquid di/polyisocyanates and polyols with a catalyst and various additives in a reactor. Polymer properties are modified with stepwise additions of these chemicals at different points in time depending on whether the process has reached an equilibrium. NCO functional groups from unreacted isocyanates must be quenched at the end for a finished product, and this parameter must be known to determine the proper chemical mixing ratio. A fast, non-destructive real-time measurement of %NCO can be obtained by using NIR spectroscopy with a probe seated directly in the reactor.

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

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

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

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

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

A safer way to monitor moisture content in crude distillation unit overhead fractions is with inline near-infrared spectroscopy using the 2060 The NIR-Ex Analyzer.

This Process Application Note provides a detailed account of the inline assessment of moisture during a pilot scale granulation process using a 2060 The NIR Analyzer.

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

In the pharmaceutical industry, the fluid bed granulator/dryer is an integral point in the manufacture of powdered materials. Residual moisture must be kept within certain specifications to avoid fracturing of particles or caking (stickiness) of the bulk material. Current methods are slow and cumbersome, which can lead to damaged or degraded product. The ability to monitor the residual moisture content inline after drying is possible with near-infrared spectroscopy (NIRS). The 2060 The NIR Analyzer offers fast, reagent-free, nondestructive analysis of residual moisture of powders with a fluid bed probe specifically designed for these applications.

This Process Application Note presents a method to closely monitor low levels of moisture in propylene oxide safely and reliably by using a single explosion-proof inline process analyzer.

In refineries, high octane products are desired since they are used to produce premium gasoline. Catalytic reforming converts heavy naphtha into a high octane liquid product called reformate (a mixture of aromatics and iso-paraffins C7 to C10). The reformate must be constantly monitored to ensure high throughput along the refining process. Traditionally, the octane numbers can be measured by two different methodologies: Inferred Octane Models (IOM) and laboratory octane engine analysis. However, these do not provide «real-time» results and require constant maintenance and human intervention to adapt to current operation conditions. «Real-time» analysis of the octane number in fuels can be performed online via near-infrared spectroscopy (NIRS) technology, which fits well within the international standards (ASTM). Utilization of a Metrohm Process Analytics NIRS XDS Process Analyzer (ATEX version) in conjunction with a sample preconditioning system makes analysis of the octane number simple, fast, and reliable, allowing quick adjustments to the process for a better quality product and higher profitability.

This Process Application Note presents a way to closely monitor multiple parameters simultaneously during the dioctyl terephthalate production process with near-infrared spectroscopy.

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.

Rapid inline monitoring of the major SC1/SC2 bath constituents is possible with reagent-free near-infrared spectroscopy, e.g., the 2060 The NIR-R Analyzer.

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

Many fermentation quality parameters can be monitored simultaneously directly in the tank with inline near-infrared spectroscopy, such as the 2060 The NIR Analyzer.

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

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

This 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.

Adulteration in the food industry is a significant concern due to potential health risks and changes in product quality and nutrition. Detecting such adulteration is challenging, however, to ensure high-quality products, precise measurements during the manufacturing process are essential for identifying any contamination in raw materials and final products. This Process Application Note details the inline analysis of potato starch in the wheat flour manufacturing process with a 2060 The NIR Analyzer from Metrohm Process Analytics.

Etching is a vital process in semiconductor fabrication, involving the chemical removal of layers from the wafer substrate. Strict quality control measures are necessary to determine acid etchant concentrations in mixed acid solutions (e.g., SPM, DSP, or DSP+), critical for optimizing etch rate, selectivity, and uniformity during multiple wafer etching steps. This application presents a method to measure sulfuric acid and hydrogen peroxide in etching baths simultaneously using Raman spectroscopy with the PTRam Analyzer from Metrohm Process Analytics.

Boric acid is growing in demand for various industrial applications, but requires a more cost-efficient and environmentally friendly production process. This Application Note describes the performance of a Raman process analyzer (PTRam) when measuring low-concentration boric acid and sodium sulfate solutions (<100 mg/L) during boric acid production.

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

This Process Application Note presents a method to accurately monitor lactic acid and glucose inside a bioreactor in «real-time» with the 2060 Raman Analyzer from Metrohm Process Analytics.

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

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

This Application Note explains how the 2060 XRF Process Analyzer enables real-time chemical monitoring of copper, tin, and zinc concentrations in white bronze plating baths.

The 2060 XRF Process Analyzer continuously monitors elemental concentrations online within zinc-nickel electroplating baths to precisely guide chemical dosing.

A solar cell or photovoltaic cell is a device that converts light energy into electrical energy. Dye-sensitized solar cells (DSC) are currently the subject of intense research in the context of renewable energies as a low-cost photovoltaic (PV) device. Electricity generated from a PV produces zero emissions, is modular, and can produce energy anywhere the sun shines. The standard characterization technique of a PV device consists in the determination of the DC current-voltage curves under different incident light intensities.

DC techniques do not provide any information about the internal dynamics of the PV device. Therefore, additional information can be obtained using time-dependent and frequency-dependent measurements. Electrochemical impedance spectroscopy in particular, offers the possibility to investigate the behavior of the device in the frequency domain under operating conditions, at various light intensities.

Dye-sensitized solar cells (DSC) are currently subject of intense research in the framework of renewable energies as a low-cost photovoltaic (PV) device. To characterize photovoltaic devices, two additional frequency domain methods can be used, based on the modulation of the light intensity. These two methods are Intensity modulated photovoltage spectroscopy (IMVS): measurement of the transfer function between the modulated light intensity and the generated AC voltage, and Intensity modulated photocurrent spectroscopy (IMPS): measurement of the transfer function between the modulated light intensity and the generated AC current.This Application Note illustrates the use of the Metrohm Autolab PGSTAT302N equipped with a FRA32M module, in combination with the Autolab Optical Bench kit to perform IMVS and IMPS characterization of photovoltaic devices.

This application note shows how it is possible with Metrohm Autolab PGSTATs and the Metrohm Autolab Optical Bench, to retrieve information about the mechanism and the kinetics of the back reaction, a side reaction which limits the performances of dye-sensitized solar cells.

In this document, a procedure to calibrate the LED light of the Metrohm Autolab Optical Bench is presented. The procedure can be applied to the single-wavelength LED lights. Calibration is performed in order to relate the LED light intensity to the LED driver current. In this way, it is possible to correct the light intensity values when the distance between the solar cell under test and the LED light is changed. Additonally, the calibration allows the user to perform measurements on solar cells while specifying the light intensity values, instead of the LED driver current.

This Application Note presents the procedure to determine the responsitivity value for calibrating the white lights of the Metrohm Autolab Optical Bench.

Determination of trace levels of chloride, nitrate, phosphate, and sulfate in boiler feed water using anion chromatography with conductivity detection after chemical suppression.

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

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

Water of the primary cycle of pressurized water reactors (PWR) contains boron for neutron absorption. The high borate content interferes with the direct analysis of trace anions. Inline Neutralization combined with variable preconcentration and Inline Matrix Elimination (MiPCT-ME) allows to remove boron as boric acid before injection.

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

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.

The thermostability of polyvinyl chloride (PVC) was determined using the dehydrochlorination procedure at 180 °C. Comparison of the thermostability of pure PVC polymer, blended PVC (blended with stabilizer, plasticizer, filler) and blended PVC after processing.

In this Application Note, the 893 Professional Biodiesel Rancimat measures the oxidation stability of biodiesel (or fatty acid methyl esters, FAME), an eco-friendly fuel.

The oxidation stability of biodegradable lubricating oil is determined using the Rancimat method.

Instant noodles have become very popular in many parts of the world. During the production process instant noodles are deep-fried, which enables a quick preparation for the consumer. Due to their high fat content (up to 22%), instant noodles can get rancid. The 892 Professional Rancimat can be used to determine the oxidation stability of deep-fried instant noodles without prior fat extraction.

The 892 Professional Rancimat can be used for determining the oxidation stability of fats contained in solid, non-meltable foodstuffs, such as peanuts, almonds, potato chips (crackers), cookies and french fries. The crushed samples can be used directly without extraction of the fat.

Oxidation of sweet almond oil can occur over time, affecting its organoleptic characteristics. This Application Note describes the reproducible and accurate determination of oxidation stability of sweet almond oil using the 892 Professional Rancimat.

Using the Rancimat method, the oxidation stability of suntan oil can be determined reproducibly and reliably.

Determination of the thermostability of polyvinyl chloride (PVC) using the dehydrochlorination procedure at 200 °C.

Wax has theoretically an unlimited shelf life, however many additives (flavor, softener, etc.) can affect it negatively. Since both synthetic and natural waxes are used in various products, such as cosmetics and foods, expiry dates have to be specified. The oxidation stability can give an approximate indication for the shelf life. A reproducible and accurate determination of the oxidation stability using the 892 Professional Rancimat can be realized.

Motor oils are exposed to high shear forces and temperatures while the motor is running. Mechanical abrasions set iron and copper free, which act as catalysts for oxidation. All of this decreases the durability of motor oils. The oxidation stability with iron and copper catalysts can give an approximate indication for the shelf life. A reproducible and accurate determination of the oxidation stability using the 892 Professional Rancimat can be realized.

Lipsticks and lip balms consist mainly of natural oils such as seed oils, palm oils or coconut oils. Many manufacturers additionally enhance their product with various vegetable fats, oils and wax. The purpose of these additives is to increase the perceived quality of the products. However, some of these oils and fats are capable to oxidize by autoxidation over time which affects the shelf life and therefore the quality of the products negatively. A reproducible and accurate determination of the oxidation stability using the 892 Professional Rancimat can be realized.Find the method explained in the Metrohm LabCast video at https://youtu.be/xdOmyeyc7Cs

Some samples, such as cosmetics and food, cannot be measured directly with the Rancimat as no evaluable induction time is obtained. There are many reasons for this, for example a high water content, a too low fat content or various matrix effects. However, using polyethylene glycol (PEG) as carrier material, many of these samples can be directly and reproducibly measured without sample preparation. This is due to the antioxidants that are naturally present in the sample matrix, and which stabilize the induction time of the PEG. The induction time can therefore be directly related to the oxidation stability of the sample.Furthermore, with a standard addition it is possible to measure the content of antioxidants (AOC) such as vitamin E, vitamin C or an equivalent of it. The decrease of the antioxidants over time (for example, during storage of the sample) can thus be measured and evaluated. In addition, this method eliminates a costly sample preparation. A reproducible and accurate determination of the oxidation stability using the 892 Professional Rancimat can be realized.

The oxidation stability is an important factor for the quality of cosmetics. It also provides information about the long-term and storage stability of the product. Most cosmetic formulations cannot be measured directly with the Rancimat as no evaluable induction time is obtained. There are many reasons for this, for example a high water content, a too low fat content or various matrix effects. However, using polyethylene glycol (PEG) as carrier material, many of these samples can be directly and reproducibly measured without sample preparation. This is due to the antioxidants that are naturally present in the sample matrix, and which stabilize the induction time of the PEG. The induction time can therefore be directly related to the oxidation stability of the sample.In addition, this method eliminates a costly sample preparation. A reproducible and accurate determination of the oxidation stability using the 892 Professional Rancimat can be realized. In this Application Notes the oxidation stability of body care cream, moisturizer, body milk, body lotion, and toothpaste is determined in this way. More information on the Rancimat method can be found on the Metrohm website.

Oxidation stability is an important quality criterion of chocolate as it provides information about the long-term stability of the product. Cocoa contains various flavonoids that act as antioxidants. The most important and common flavonoids are catechin, epicatechin, and procyanidin. Although the flavonoid content may vary amongst chocolate type, it can be said, the greater the cocoa content in the chocolate, the greater the antioxidant effect.Chocolate cannot be measured directly with the classical Rancimat method, as no evaluable induction time is obtained. There are many reasons for this, for example a too low fat content or various matrix effects. Traditionally, extraction of the fat from the chocolate using e.g., petroleum ether is therefore necessary.In this Application Note, the oxidation stability of white, milk and dark chocolate with varying cacao content is determined in without extraction. Instead, polyethylene glycol is used as conducting medium. More information on the Rancimat method can be found on the Metrohm website.

Oxidation stability is an important parameter to assess the quality of animal feed. It provides information about the long-term resistance to degradation of the fatty acids, which can predict the storage stability of the product. Oxidation stability of many animal feeds can be directly and reproducibly measured by the Rancimat method, if polyethylene glycol (PEG) is used as the carrier material.No sample preparation is required for this application. This Application Note describes the determination of oxidation stability of fish food and dog treats. More information on the Rancimat method can be found on the Metrohm website.

Oxidation stability is an important parameter defining the quality of tea. It also provides information about the long-term stability of the naturally included antioxidants and thus the stability of the product. However, tea cannot be measured directly with the Rancimat method, as no evaluable induction time is obtained. The reason for this is that no measurable oxidation product is formed. However, using polyethylene glycol (PEG) as carrier material, many of these samples can be directly and reproducibly measured without any sample preparation. This is due to the antioxidants that are naturally present in the sample matrix, which stabilize the induction time of the PEG. The induction time can therefore be directly related to the oxidation stability of the sample.A reproducible and accurate determination of the oxidation stability is feasible using the 892 Professional Rancimat. In this Application Notes the oxidation stability of different teas is determined in this way. More information on the Rancimat method can be found on the Metrohm website.

The freshness as well as the smell and taste of coffee depend, among other things, on the content of antioxidants. The antioxidant content is critical to set a retail price and therefore it is of great interest for manufacturers and distributors to determine it. Classically, this parameter is determined via long-term storage tests. Oxidation stability offers a fast, alternative method, which can define the quality of coffee.Using the modified Rancimat method, the oxidation stability of coffee can be determined quickly and reliably. The sample is analyzed together with polyethylene glycol (PEG). The antioxidants present in the sample matrix stabilize the induction time of the PEG. The induction time can therefore be related directly to the oxidation stability and antioxidant content of the sample.This Application Note demonstrates the feasibility of the modified Rancimat method. Using the 892 Professional Rancimat, reproducible and accurate determination of the oxidation stability of different coffees is possible.

The thermal stability of raw or processed PVC provides information about the quality of the plastic. Higher stability times can be correlated with longer lifespans. With the 895 Thermomat, the dehydrochlorination rate at elevated temperatures can be determined within a short time. Additionally, quality deviations in the purchased raw material as well as in the end products can be detected. The 895 Thermomat has been optimized for this application regarding three important points: safety, handling, and time-savings. The measurement is based on the standard EN ISO 182-3.

The determination of the oxidation stability of wine with the Rancimat is a newly developed method able to determine the antioxidant potential of wines. Different grapes as well as varied processing methods impart the color, taste, and anti-oxidative capacity for each wine blend or varietal. With the Rancimat and Polyethylene Glycol (PEG) methods, the antioxidant potential in different wines can be easily compared.The PEG method is used to compare the antioxidant capacity of different vintages and grape varieties. The induction time can be used as a quality criterion for different types of wine or different vintages. In this Application Note, the oxidation stability of different wines is determined in this way.

This Application Note demonstrates the feasibility of the Rancimat method. Reproducible and accurate determination of the oxidation stability of flavored spirits is possible with the 892 Professional Rancimat.

Determining the oxidation stability of raw materials for the cosmetic and pharmaceutical industry.

The oxidative stability of sunflower oil using AOCS Cd 12b-92, EN ISO 6886, and a method based on EN ISO 6886 from Metrohm are compared. No significant differences are found.

This Application Note describes the determination of the oxidation stability of different sausages with the recommended method from Metrohm using an 892 Professional Rancimat.

This Application Note describes the determination of the oxidation stability of the fat in different sausages extracted with cold petroleum ether using an 892 Professional Rancimat.

Higher antioxidant levels mean longer product viability. The 892 Professional Rancimat determines antioxidant content in many products using a linear regression method.

Sustainable biodiesel can be blended with petroleum diesel. The 893 Professional Biodiesel Rancimat measures the oxidation stability of biodiesel and its blends.

Processing degrades antioxidant levels in spices. The 892 Professional Rancimat determines oxidation stability with the PEG method as per AOCS Cd 12b-92 and ISO 6886.