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

The combination of 850 Professional IC, 858 Professional Sample Processor, Dosino and MagIC NetTM software offers a variety of sophisticated ion chromatographic sample preparation techniques. One of these is the automated inline dilution of samples.After the first sample injection, MagIC NetTM verifies if the area of the sample peak lies within the calibration range. If the measured peak area is outside these limits, the software calculates the appropriate dilution factor, dilutes and automatically re-injects the sample. For all investigated ions (Li+, Na+, K+, Ca2+, Mg2+, F-, Cl- , NO2-, Br-, NO3-, SO42- ), automated logical dilution yielded coefficients of determination (R2) better than 0.9999. Direct-injection recoveries for cations and anions were within 98.6…99.5% and 93.4…100.4% respectively. In contrast, after logical dilution, recoveries for cations and anions were within 100.1…102.9% and 98.2…102.6% respectively. The relative standard deviations for all determinations involving diluted sample solutions were smaller than 0.91%.

The analytical challenge treated by the present work consists in detecting sub-ppm quantities of bromide, sulfate, aliphatic monocarboxylic acids and several alkaline earth metals in the presence of very high concentrations of sodium and chloride. Bromide, sulfate, acetate and butyrate can be reliably determined by suppressed conductivity detection. Due to matrix effects, propionate can only be detected qualitatively. This drawback can be overcome by coupling the ion chromatograph (IC) to a mass spectrometric (MS) detector. This results in reduced matrix interferences and significantly enhanced sensitivities. The cations magnesium, barium and strontium are determined by non-suppressed conductivity detection.

The study of adverse effects of air pollution requires semi-continuous, rapid and accurate measurements of inorganic species in aerosols and their gas phase components in ambient air. The most promising instruments, often referred to as steam collecting devices, are the Particle-Into-Liquid-Sampler (PILS) coupled to wet-chemical analyzers such as a cation and/or anion chromatograph (IC) and the Monitoring instrument for AeRosols and GAses (MARGA) with two integrated ICs. Both instruments comprise gas denuders, a condensation particle growth sampler as well as pump and control devices. While PILS uses two consecutive fixed denuders and a downstream growth chamber, the MARGA system is composed of a Wet Rotating Denuder (WRD) and a Steam-Jet Aerosol Collector (SJAC). Although the aerosol samplers of PILS and MARGA use different assemblies, both apply the technique of growing aerosol particles into droplets in a supersaturated water vapor environment. Previously mixed with carrier water, the collected droplets are continuously fed into sample loops or preconcentration columns for on-line IC analysis. While PILS has been designed to sample aerosols only, MARGA additionally determines water-soluble gases. Compared to the classical denuders, which remove gases from the air sample upstream of the growth chamber, MARGA collects the gaseous species in a WRD for on-line analysis. In contrast to the gases, aerosols have low diffusion speeds and thus neither dissolve in the PILS denuders nor in the WRD. Proper selection of the ion chromatographic conditions of PILS-IC allows a precise determination, within 4 to 5 minutes, of seven major inorganic species (Na+, K+, Ca2+, Mg2+, Cl-, NO3- and SO4 2-) in fine aerosol particles. With longer analysis times (10-15 minutes) even airborne low-molecular-weight organic acids, such as acetate, formate and oxalate can be analyzed. MARGA additionally facilitates the simultaneous determination of HCl, HNO3, HNO2, SO2 and NH3.PILS and MARGA provide semi-continuous, long-term stand-alone measurements (1 week) and can measure particulate pollutants in the ng/m3 range.

The analytical challenge treated in the present work consists in detecting trace concentrations (ppb) of bromide in the presence of a strong chloride matrix. This problem was overcome by separating the bromide ions from the main fraction of the early eluting chloride matrix (several g/L) by applying two sequential chromatographic separations on the same column. After the first separation, the main fraction of the interfering chloride matrix is flushed to waste, while the later eluting anions are diverted to an anion-retaining preconcentration column. After elution in counter flow, the bromide ions are efficiently separated from the marginal chloride residues. The four-point calibration curves for bromide and sulfate are linear in the range of 10…100 µg/L and 200…800 µg/L and yield correlation coefficients of 0.99988 and 0.99953 respectively. For the method shown here, a second injection valve and a preconcentration column are the only additional devices needed to master this demanding separation problem.

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.

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

The analytical challenge treated in the present work consists in the determination of chloride, phosphate and sulfate in the presence of difficult sample matrices that interact with the stationary column phase or even render it unusable. Metrohm`s patented stopped-flow dialysis coupled to the new 881 Compact IC pro ion chromatograph overcomes these drawbacks. Two standard solutions covering the concentration ranges 1.0…3.6 mg/L and 10…36 mg/L as well as two samples, an ultra-high temperature (UHT) processed milk and a baby milk powder, were characterized in terms of analyte concentration, relative standard deviation, calibration quality, carryover and recovery rates. While the five-point calibration curves yielded correlation coefficients (R) better than 0.9999, carryover (between two subsequent injections of a concentrated sample and a blank) was less than 0.49%. Recoveries for the low (10…36 mg/L) and high standard concentrations (1.0…3.6 mg/L) were within 91…99% and 94…100%, respectively. Automated compact stopped-flow dialysis is a leading-edge sample preparation technique that ensures optimum separation performance by effectively protecting the column from detrimental matrix compounds.

Sodium fluoride is used as a preservative in biological samples for alcohol analysis. All submitted blood samples, including those taken from vehicle drivers suspected of driving under the influence of liquor, have to be tested for adequate preservation prior to alcohol determination by gas chromatography. This is critical to ensure adequate sample preservation. Inadequate sample preservation may allow glycolysis and/or microorganism growth to produce ethanol.In the past this has been done by direct potentiometric measurement using a fluoride-selective electrode (F ISE), an ion meter and certified NaF standards. The sodium fluoride level was determined manually by dipping the electrode directly into the blood sample. Results were recorded manually. This poster describes two independent automated methods of analysis that allow the minimization of this tedious and time-consuming procedure.In the first one, the fluoride content in a blood aliquot is measured by direct potentiometric measurement after the addition of TISAB and deionized water. The second method employs the titration of the sample aliquot with La(NO3)3 after adding a buffer solution.

Available sample size, mass sensitivity, efficiency and the detector type are important criteria in the selection of separation column dimensions. Compared to conventional 4 mm i.d. columns, microbore columns excel, above all, by their low eluent consumption. Once an eluent is prepared, it can be used for a long time. Additionally, the lower flow rates of microbore columns facilitate the hyphenation to mass spectrometers due to the improved ionization efficiency in the ion source.With the same injected sample amount, a halved column diameter involves a lower eluent flow and results in an approximate four-fold sensitivity increase. In a converse conclusion, this means that with less sample amount, microbore columns achieve the same chromatographic sensitivity and resolution than normal bore columns. This makes them ideally suited for samples of limited availability.

Metrohm`s intelligent Preconcentration Technique with Matrix Elimination (MiPCT-ME) excels in its capacity to perform automatic ion chromatographic determinations over 6 orders of magnitude. Crucial requirements for this are the system`s intelligence and the exact measurement of the sample volume. While the intelligence allows to compare results and take decisions, the dosing device takes over the high-precision liquid handling of even single-digit microliter volumes to the preconcentration column. By using only one analytical setup and without additional rinsing, samples containing both ultratraces and high concentrations can be analyzed.As the other Metrohm Inline Techniques, the MiPCT-ME technique presented reduces the workload, ensures complete traceability, is free of carryover effects and significantly improves accuracy and reproducibility of the results.

The poster presents the ion chromatographic determination of organic degradation products such as glycolate, formate and acetate besides the standard anions fluoride, chloride, nitrate and sulfate.

Determination of chloride and sulfate in the presence of high nitrate concentrations. Optimization of the chromatographic separation by variation of the temperature and eluent composition.

Three different suppressor systems are compared in terms of sensitivity. Additionally, binary gradient elution was applied to analyze phosphates in the presence of mono- and divalent ions.

The poster describes how different suppressors (MSM and MCS) work and mentions possible applications.

The Combustion IC system presented allows the automated determination of organic halogen and sulfur compounds in all flammable samples. Both combustion digestion, which is automatically controlled with a flame sensor, and the professional Liquid Handling guarantee highest precision and trueness. This poster describes the determination of the halogen and sulfur content in a certified polymer standard, a coal reference material as well as in latex and vinyl gloves.

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.

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.

If chloride and bromide are present in approximately equal molar concentrations they can be titrated directly with silver nitrate solution after addition of barium acetate. If, however, the molar ratio n(Br-) : n(Cl-) changes from 1 : 1 to 1 : 5, 1 : 10, 5 : 1 or 10 : 1 then greater relative errors must be expected with this method. The Bulletin describes an additional titration method that allows bromide to be determined in the presence of a large excess of chloride. The determination of small chloride concentrations in the presence of a large excess of bromide is not possible by titration.

This Bulletin describes fluoride determination in various matrices with the help of the ion-selective fluoride electrode (F-ISE). The F-ISE is comprised of a lanthanum fluoride crystal and exhibits a response in accordance with the Nernst equation across a wide range of fluoride concentrations.The first part of this Bulletin contains notes regarding the handling and care of the electrode and the actual fluoride determination itself. The second part demonstrates the direct determination of fluoride with the standard addition technique in table salt, toothpaste and mouthwash.

Bromide is removed from the sample as BrCN by distillation. The BrCN is absorbed in sodium hydroxide solution and decomposed with concentrated sulfuric acid, then the released bromide ions are determined by potentiometric titration with silver nitrate solution. Iodide does not interfere with the determination. Iodide is oxidized to iodate by hypobromite. After destruction of the excess hypobromite, the potentiometric titration (of the iodine released from iodate) is carried out with sodium thiosulfate solution. Bromide does not interfere, even in great excess. The described methods allow the determination of bromide and iodide in the presence of a large excess of chloride (e.g., in brine, seawater, sodium chloride, etc.).

The determination of the physical and chemical parameters as electrical conductivity, pH value, p and m value (alkalinity), chloride content, the calcium and magnesium hardness, the total hardness, as well as fluoride content are necessary for evaluating the water quality. This bulletin describes how to determine the above mentioned parameters in a single analytical run. Further important parameters in water analysis are the permanganate index (PMI) and the chemical oxygen deman (COD). Therefore, this Bulletin additionally describes the fully automated determination of the PMI according to EN ISO 8467 as well as the determination of the COD according to DIN 38409-44.

This Bulletin gives a survey of standard methods from the field of water analysis. You will also find the analytical instruments required for the respective determinations and references to the corresponding Metrohm Application Bulletins and Application Notes. The following parameters are dealt with: electrical conductivity, pH value, fluoride, ammonium and Kjeldahl nitrogen, anions and cations by means of ion chromatography, heavy metals by means of voltammetry, chemical oxygen demand (COD), water hardness, free chlorine as well as a few other water constituents.

This Bulletin describes the determination by ion chromatography of anions, particularly fluoride, chloride, nitrite, bromide, nitrate, and sulfate using the Hamilton PRPX100 IC anion column without chemical suppression.

Copper concentrate is an important raw material for copper mills. The concentrate is often contaminated with corrosive fluorine, which is why the fluorine concentration must be checked at regular intervals. A convenient and reliable determination method is Combustion IC in combination with sacrificing vial technology. The sample is placed inside the quartz combustion pipe in a horizontally positioned quartz vial, both ends of which are sealed with glass wool. During combustion, the quartz-destroying components (e.g., fluoride, alkali and earth alkali metals) that are released are captured by the quartz vial and the quartz wool, ensuring that they are thus unable to reach the quartz combustion pipe at all. Keyword: pyrohydrolysis

Coal contains a certain amount of fluorine, chlorine, and sulfur compounds. During combustion of the coal, these components release corrosive acids (e.g., fluorine compounds form hydrofluoric acid). Thermal power plants therefore request low-fluorine coal to avoid massive hydrofluoric acid production. In this application note, fluorine content in coal is determined by ion chromatography after pyrohydrolysis.

Ezetimibe is a cholesterol-reducing drug. It reduces the cholesterol resorption in the small intestine. The molecule holds two fluorophenyl groups. Applying Combustion IC the amount of fluorine in the drug is determined. To avoid an excessive introduction of fluoride into the system, Ezetimibe is dissolved in ethanol prior to the combustion.

Polymer materials that are used for building and decoration purposes need to be flame resistant. To reach the required level of resistance flame-retardants are added to the plain polymer. Flame-retardants are often haloorganic compounds. The use of such components and the respective concentration of introduced halogens can be determined by Combustion IC. The recovery over the full system is tested with a certified reference material (CRM).

Iron ore is an important resource for steel production. Its natural content of halogens is a quality characteristic due to the corrosiveness of the respective halogenides. Combustion IC applying the sacrificial vial technology is used for the analysis of fluorine and chlorine in ore. WO3 usually is added to improve the release of SO2 and therefore sulfur recovery. In this application, it also significantly improves the recovery of fluoride.

In textiles, the water-repelling effect may be introduced by different treatments, such as the application of fluorochemicals. These compounds, especially perfluoroorganic substances, are extremely persistent in the environment and are therefore listed as emergent contaminants. Combustion IC with pyrohydrolysis and subsequent ion chromatographic determination is applied to analyze the fluorine content in fabrics.

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

AOF (flo hữu cơ hấp phụ) được sử dụng để sàng lọc các chất alkyl per- và polyfluorinated trong các chất nền nước thông qua quá trình đốt cháy nhiệt phân và sắc ký ion.

Combustion ion chromatography (CIC) measures AOX (adsorbable organically bound halogens, i.e., AOCl, AOBr, AOI) and AOF as well as CIC AOX(Cl) according to DIN 38409-59 and ISO 18127.

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

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

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

This Application Note explains how fluoride determination in acid etching baths can be performed with thermometric titration.

Determination of bromide and chloride in photographic developer solutions.

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.

Results from three separate single endpoint titrations are used to calculate the results. The mixture of H2SO4, HF, and NH4F/HF contains H+ from H2SO4, HF, and NH4F/HF, SO42- from H2SO4, and F- from HF and NH4F/HF. Analysis of total H+ («total acids») by NaOH titration, F- by titrating with Al(NO3)3 («total fluoride») and SO42- by titrating with BaCl2 provides the information required to determine the composition of the mixture.

A direct thermometric titration (TET) with 2 mol/L NaOH is used to determine the HF, NH4F, and maleic acid (C4H4O4) contents of acid cleaning solutions. Three endpoints (EPs) are obtained, which may be assigned as follows: EP1: C4H4O4 (pKa1 = 1.9), HF (pKa = 3.17) EP2: C4H4O4 (pKa2 = 6.07) EP2: NH4F (pKa = 8.2) The HF content is determined by subtracting the difference (EP2-EP1) from EP1.

Fluoride protects dental enamel and is an important trace element in toothpaste. A rapid and precise determination is made via standard addition with the help of an ion-selective fluoride electrode (F-ISE).

Determination of fluoride in a chromium plating bath by direct potentiometry using the F-ISE.

Determination of fluoride in cement or clinker by direct potentiometry with the F-ISE.

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.

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

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

Increased fluoride concentrations in water may cause tooth damage, growth disorders, and bone deformation. According to the World Health Organization (WHO), concentrations above 1.5 mg/L are critical. One possible source of fluoride is landfills. Rain washes out harmful substances from landfills which can enter the groundwater. The leachate from landfills should thus be monitored for the fluoride concentration. Ion measurement is a fast and inexpensive method to determine the fluoride content in water samples compared to other methods such as ion chromatography. This Application Note describes a reproducible and accurate measurement of the fluoride content using the fluoride ion-selective electrode with an OMNIS system.

Determination of bromide and bromate in drinking water using anion chromatography with MS detection.

The new DIN draft standard 38407-53 outlines TFA analysis in water using direct injection LC-MS/MS, enabling quantification from 0.1–3.0 μg/L as shown in this Application Note.

Determination of anions in solder paste after alcoholic extraction using anion chromatography with direct conductivity detection.

Determination of anions in a Schoeniger absorption solution of a test mixture without decomposition of the H2O2 using anion chromatography with direct conductivity detection.

Determination of acetate, formate, chloride, bromide, and sulfate in toluene using anion chromatography with direct conductivity detection.

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

Determination of fluoride, chloride, nitrite, nitrate, and sulfate in an effluent sample using anion chromatography with direct conductometric detetction.

Determination of traces of iodide in HCl (25%) using anion chromatography with amperometric detection at a silver electrode.

Determination of traces of nitrite, thiosulfate, and iodide using anion chromatography with amperometric detection at the carbon paste electrode.

Determination of traces of bromide and iodide using anion chromatography with amperometric detection at the silver electrode.

Determination of traces of bromide in HCl (32%) using anion chromatography with amperometric detection at the silver electrode.

Determination of fluoride and chloride in gypsum using anion chromatography and subsequent direct conductometric detection.

Determination of traces of iodide in acetic acid using anion chromatography with amperometric detection at the carbon paste electrode.

Determination of iodide in wastewater (dye industry) using anion chromatography with amperometric detection at the silver electrode and dialysis for sample preparation.

Pure sodium chloride contains much less iodide than e.g., table salt which usually is fortified with it. Trace determination of iodide is easily performed applying ion chromatography with amperometric detection. This detection mode is particularly selective and sensitive. The actual separation is achieved using a Metrosep A Supp 5 - 250/4.0 column. The detection happens at a silver working electrode. LOQ is at approximately 1.0 μg/L (in solution) and 50 μg/kg in the sample. The use of a shorter column might further improve the LOQ.

The synthetic rubber known as Bromobutyl (BIIR) has many of the attributes of butyl rubber, but has better adhesion to other rubbers and metals, resulting in substantially faster cure rates. The simultaneous quantification of the bromine content, Mooney viscosity, volatile content, calcium stearate content, and functional bromide in BIIR can be easily performed with near-infrared spectroscopy (NIRS) without the use of chemicals.

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

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.

Các biện pháp giám sát hoặc ngăn ngừa ăn mòn là rất quan trọng trong các nhà máy điện hạt nhân, nơi có thể xảy ra các rủi ro đáng kể đối với sức khỏe và an toàn nếu không kiểm soát ăn mòn. Các anion ăn mòn kim loại dưới nhiệt độ và áp suất cao, do đó, nồng độ của chúng phải luôn được theo dõi. Thách thức phân tích trong mạch chính là phát hiện các anion trong khoảng & mu; g / L cùng với lượng gam axit boric và liti hydroxit. Phân tích dấu vết chính xác, đáng tin cậy đòi hỏi phương pháp phải được tự động hóa hết mức có thể. Máy phân tích quá trình vi mạch 2060 của Metrohm Process Analytics có thể đo một số anion từ một lần bơm, với sự kết hợp của sự tập trung trước nội tuyến và loại bỏ ma trận nội tuyến để đo nồng độ anion thấp một cách chính xác và đáng tin cậy theo thời gian.

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 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.

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.

Determination of the anions in potable water using anion chromatography with conductivity detection after chemical suppression.

Determination of fluoride, chloride, nitrite, nitrate, phosphate, and sulfate in cooling water using anion chromatography with conductivity detection after chemical suppression.

Determination of fluoride, chloride, nitrite, bromide, nitrate, and sulfate in surface water using anion chromatography with conductivity detection after chemical suppression.

Determination of fluoride, chloride, nitrite, nitrate, and sulfate in soil eluates using anion chromatography with conductivity detection after chemical suppression.

Determination of chloride, bromide, and sulfate in synthetic seawater using anion chromatography with conductivity detection after chemical suppression.

Determination of fluoride, chloride, and nitrate in a solution of NiSO4, ZnSO4 in sulfuric acid using anion chromatography with conductivity detection after chemical suppression.

Determination of chloride, bromide, phosphate, and sulfate in an ashed baking additive using anion chromatography with conductivity detection after chemical suppression.

Determination of 1 (3) µg/L of chloride, nitrite, bromide, nitrate, phosphate, and sulfate after direct injection using anion chromatography with conductivity detection after chemical suppression.

Determination of fluoride, nitrate, phosphate, and sulfate in an etching reagent using anion chromatography with conductivity detection after chemical suppression.

Determination of fluoride, chloride, nitrate, phosphate, and sulfate in surface water using anion chromatography with conductivity detection after chemical suppression; nitrite with electrochemical detection (conductivity and ELCD detectors in series).

Determination of bromide, nitrate, and phosphate in wastewater using anion chromatography with conductivity detection after chemical suppression and dialysis for sample preparation.

Determination of bromide and phosphate in waste dump drainage water in the presence of very high concentrations of other ions and organic substances using anion chromatography with conductivity detection after chemical suppression and dialysis for sample preparation.

Determination of bromide and sulfate using anion chromatography with conductivity detection after chemical suppression.

Determination of fluoride, chloride, nitrite, nitrate, and sulfate in rainwater using anion chromatography with conductivity detection after chemical suppression.

Determination of fluoride, chloride, phosphate, and sulfate in boric acid using anion chromatography with conductivity detection after chemical suppression.

Reproducibility of fluoride, chloride, nitrite, bromide, nitrate, and sulfate in the ppb range using anion chromatography with conductivity detection after chemical suppression.

Determination of fluoride, chloride, bromide, nitrate, sulfate, and iodide in rock leachant using anion chromatography with conductivity detection after chemical suppression.

Determination of fluoride, chloride, bromide, and sulfate in bath salts (sea salt) using anion chromatography with conductivity detection after chemical suppression.

Determination of fluoride, chloride, nitrate, phosphate, and sulfate in boric acid with sample preconcentration using anion chromatography with conductivity detection after chemical suppression.

Determination of traces of fluoride, chloride, nitrate, phosphate, and sulfate in 15% NaOH using anion chromatography with conductivity detection after chemical suppression and inline sample neutralization.

Determination of chloride, bromide, and sulfate in photographic process wastewater using anion chromatography with conductivity detection after chemical suppression.

Determination of iodide and thiosulfate in photographic process wastewater using anion chromatography with amperometric detection at the carbon paste electrode after chemical suppression.

Determination of chloride, bromide, and sulfate in seawater using anion chromatography with conductivity detection after chemical suppression.

Determination of fluoride, chloride, phosphate, and monofluorophosphate in glutamine monofluorophosphate using anion chromatography with conductivity detection after chemical suppression.

Determination of fluoride, chloride, nitrate, sulfite, phosphate, and sulfate in wastewater using anion chromatography with conductivity detection after chemical suppression.

Determination of iodide in common salt using anion chromatography with amperometric detection at the silver electrode.

Determination of fluoride, chloride, nitrate, and sulfate in corrosion powder using anion chromatography with conductivity detection after chemical suppression.

Determination of bromide in NaCl crystals using anion chromatography with conductivity detection after chemical suppression.

Determination of fluoride, chloride, bromide, sulfate, and iodide in mineral extracts using anion chromatography with conductivity detection after chemical suppression.

Determination of gluconate, fluoride, formate, chloride, nitrate, and salicylate using anion chromatography with conductivity detection after chemical suppression.

Determination of bromide and sulfate in brine (300 g/L NaCl) using anion chromatography with conductivity detection after chemical suppression.

Determination of fluoride, chloride, nitrite, bromide, nitrate, phosphate, sulfite, sulfate, and thiosulfate in colored liquors using anion chromatography with conductivity detection after chemical suppression.

Determination of fluoride, sulfate, iodide, and molybdate in mineral tablets using anion chromatography with conductivity detection after chemical suppression.

Determination of chloride, nitrite, bromide, nitrate, and sulfate in water for infusion solution production using anion chromatography with conductivity detection after chemical suppression.

Determination of chloride, nitrate, bromide, and sulfate in process wastewater using anion chromatography with conductivity detection after chemical suppression.

Determination of fluoride, chloride, nitrate, phosphate, and sulfate in wastewater using anion chromatography with conductivity detection after chemical suppression.

Determination of chloride, nitrite, bromide, nitrate, phosphate, and sulfate in Schoeniger absorption solution using anion chromatography with conductivity detection after chemical suppression.

Determination of fluoride, chloride, phosphate, monofluorophosphate, and sulfate in toothpaste using anion chromatography with conductivity detection after chemical suppression.

Determination of fluoride, glycolate, monochloroacetate, and chloride in a surfactant solution using anion chromatography with conductivity detection after chemical suppression and dialysis for sample preparation.

Determination of fluoride, glycolate, chloride, and oxalate in a latex dispersion using anion chromatography with conductivity detection after chemical suppression and dialysis for sample preparation.

Determination of chloride, bromide, nitrate, phosphate, and sulfate in 20% NaOH after inline neutralization by cation exchange on the 793 IC Sample Prep Module using anion chromatography with conductivity detection after chemical suppression.

Determination of fluoride, chloride, nitrite, nitrate, benzoate, and sulfate in PVC film using anion chromatography with conductivity detection after chemical suppression.

Determination of lactate, acetate, chloride, methylsulfate, bromide, and sulfate using anion chromatography with conductivity detection after chemical suppression.

Determination of bromide, sulfate, and iodide in 1 g/L sodium chloride using anion chromatography with conductivity detection after chemical suppression.

Determination of fluoride, chloride, nitrite, bromide, nitrate, phosphate, sulfite, and sulfate in river water using anion chromatography with conductivity detection after chemical suppression.

Determination of fluoride in adipic acid using anion chromatography with conductivity detection after chemical suppression.

Determination of iodide, thiosulfate, and thiocyanate in the presence of fluoride, chloride, nitrite, bromide, nitrate, phosphate, and sulfate using anion chromatography with a high-pressure gradient and conductivity detection after chemical suppression.

Determination of chloride, bromide, nitrate, sulfite, sulfate, phosphate, oxalate, thiosulfate, and thiocyanate (heat stable salts) in scrubber solutions using anion chromatography with conductivity detection after chemical suppression.

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

Determination of fluoride, chloride, nitrite, bromide, nitrate, phosphate, sulfate, oxalate, thiosulfate, iodide, and citrate in a standard solution using anion chromatography with a high pressure gradient and conductivity detection after chemical suppression.

Determination of traces of fluoride, chloride, bromide, nitrate, and sulfate in a boiler feed water containing 10 mg/L ammonia using anion chromatography with conductivity detection after chemical suppression and inline sample preparation by cation exchange.

Determination of traces of fluoride, acetate, formate, chloride, and sulfate in an ion exchanger eluate containing 2 g/L nitrate using anion chromatography with a step gradient and conductivity detection after chemical suppression.

Determination of the method detection limit (MDL) and method quantification limit (MQL) of bromate in drinking water using anion chromatography with conductivity detection after chemical suppression.

Determination of iodide in milk powder using anion chromatography with conductivity detection after chemical suppression and inline sample preparation by dialysis.

Determination of iodide in a table salt using anion chromatography with conductivity detection after chemical suppression.

Determination of chloride, nitrite, bromide, nitrate, and sulfate in inositol using anion chromatography with conductivity detection after chemical suppression.

Determination of fluoride, chloride, bromide, nitrate, sulfate, and trifluoroacetate (TFA) in a peptide sample using anion chromatography with conductivity detection after chemical suppression.

Determination of bromide, sulfite, sulfate, and thiosulfate in a photographic developer solution using anion chromatography with conductivity detection after chemical suppression.

Determination of fluoride, chloride, and sulfate in an absorption solution containing H2O2 using anion chromatography with conductivity detection after chemical suppression.

Determination of fluoride, acetate, formate, chloride, nitrite, nitrate, phosphate, and sulfate in wastewater containing N-methylpyrrolidone using anion chromatography with conductivity detection after chemical suppression and inline matrix elimination.

Determination of fluoride, chloride, nitrite, bromide, nitrate, phosphate, sulfate, and iodide in a mineral water using anion chromatography with conductivity detection after chemical suppression.

Determination of fluoride, nitrate, phosphate, sulfite, and sulfate in an etching bath using anion chromatography with conductivity detection after chemical suppression.

Determination of fluoride, chloride, phosphate, and sulfate in beer wort using anion chromatography with conductivity detection after chemical suppression.

Determination of iodide in a human 24 hour urine sample using anion chromatography with amperometric detection after chemical suppression. The result agrees with that of the photometric method. UV detection did not work.

Determination of 21 anions and organic acids using anion chromatography with conductivity detection after chemical suppression and applying a high pressure gradient.

Determination of fluoride, chloride, nitrite, bromide, nitrate, phosphate, and sulfate in water from an agricultural irrigation system using anion chromatography with conductivity detection after chemical suppression.

Determination of fluoride, acetate, formate, and chloride in gasoline using anion chromatography with conductivity detection after chemical suppression.

Determination of fluoride, acetate, formate, and chloride in a brake fluid using anion chromatography with conductivity detection after chemical suppression.

Determination of fluoride, chloride, nitrite, selenite, phosphate, nitrate, sulfate, and selenate using anion chromatography with conductivity detection after chemical suppression.

Determination of chloride and bromide in an absorption solution after Wickbold digestion using anion chromatographywith conductivity detection after chemical suppression.

Determination of fluoride, MSA (methylsulfonic acid), EDSA (ethyldisulfonic acid), and MDSA (methyldisulfonic acid) using anion chromatography with conductivity detection after chemical suppression.

Determination of traces of fluoride and sulfate in 35% hydrochloric acid (HCl) using anion chromatography with conductivity detection after chemical suppression and sample preparation by inline neutralization.

Qualitative determination of chloride, phosphate, and sulfate as well as chlorite, nitrite, chlorate, bromide, and chromate in urine using anion chromatography with conductivity detection after chemical suppression.

Determination of fluoride, chloride, nitrite, nitrate, and sulfate in a closed cooling water system using anion chromatography with conductivity detection after chemical suppression.

Determination of fluoride, chloride, nitrate, phosphate, and sulfate in a borate effluent using anion chromatography with conductivity detection after chemical suppression.

Determination of chloride, phosphate, sulfite, bromide, nitrate, and sulfate in a beer using anion chromatography with conductivity detection after chemical suppression.

Determination of chloride, bromide, nitrate, phosphate, and sulfate in dimethylacetamide using anion chromatography with conductivity detection after chemical suppression.

Determination of fluoride, chloride, nitrate, sulfate, and oxalate in a perfluorocarbon material using anion chromatography with conductivity detection after chemical suppression.

Fast and reliable analysis of drinking water by combining EPA method 300.1 Parts A and B in a single IC run.

Determination of fluoride, glycolate, acetate, formate, chloride, nitrite, nitrate, and sulfate in the primary cycle water of a pressurized water reactor (PWR) using anion chromatography with conductivity detection after chemical suppression calibrated with Metrohm Inline Calibration.

Determination of fluoride, acetate, formate, nitrate, and sulfate in a gasoline/bioethanol mixture (85% gasoline, 15% ethanol) using anion chromatography with conductivity detection after sequential suppression and Metrohm Inline Matrix Elimination.

Determination of fluoride in green tea using anion chromatography with conductivity detection after chemical suppression.

Determination of fluoride, acetate, propionate, formate, butyrate, chloride, nitrite, bromide, nitrate, benzoate, phosphate, sulfate, malonate, and oxalate in an industrial process water using anion chromatography with conductivity detection after sequential suppression.

Determination of fluoride, acetate, formate, chloride, sulfate, malonate, succinate, and oxalate in Bayer liquor using anion chromatography with conductivity detection after sequential suppression.

Determination of the cross contamination of 100 mg/L of fluoride, chloride, nitrite, bromide, nitrate, phosphate, and sulfate to ultrapure water using anion chromatography with conductivity detection after chemical suppression and inline ultrafiltration.

Determination of fluoride, hypophosphite, chlorite, bromate, chloride, nitrite, bromide, chlorate, nitrate, phosphite, phosphate, sulfate, arsenate, iodide, chromate, and perchlorate using anion chromatography with conductivity detection after gradient elution and chemical suppression.

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

Determination of fluoride, acetate, formate, chloride, nitrite, nitrate, phosphate and sulfate in an E85 mixture (85% ethanol and 15% gasoline) by means of anion chromatography with conductivity detection and sequential suppression. The Inline Matrix Elimination serves as sample preparation.

Determination of fluoride, chloride, bromide, and iodide in petroleum coke after microwave combustion using anion chromatography with conductivity detection after sequential suppression.

Calibration of fluoride, chloride, nitrite, bromide, nitrate, phosphate, and sulfate using intelligent partial loop injection technique and anion chromatography with conductivity detection after sequential suppression. This technique allows a calibration range of 1:100 (e.g. 1 μg/L to 100 μg/L corresponding to 2 μL to 200 μL injected volume) out of 1 calibration solution. Applying the full range of partial loop injection to the samples one calibration covers a sample concentration range of 1 to 10'000.

Determination of fluoride, acetate, formate, chloride, nitrite, nitrate, phosphate, and sulfate impurities in syringe filters using anion chromatography with conductivity detection after sequential suppression.

Determination of fluoride, chloride, nitrate, phosphate, and sulfate on a short column or the ions mentioned plus bromate and nitrite on a long column in water samples applying intelligent column-switching using anion chromatography with conductivity detection after sequential suppression.

Determination of fluoride, chloride, and nitrate in concentrated sulfuric acid (96…98%) using anion chromatography with conductivity detection after sequential suppression.

Determination of chloride, nitrite, bromide, nitrate, phosphate, sulfite, sulfate, and oxalate in a cooling lubricant using anion chromatography with conductivity detection and subsequent UV detection (see AN-U-047) after sequential suppression and Metrohm Inline Dialysis.

Determination of fluoride, formate, acetate, chloride, nitrite, bromide, nitrate, sulfate, oxalate, and molybdate using anion chromatography with conductivity detection after chemical suppression and Metrohm Inline Dialysis.

Determination of fluoride, chloride, phosphate, and sulfate in sodium tetraborate using anion chromatography with conductivity detection after sequential suppression. Inline acidification is applied to convert tetraborate into boric acid which is not retained on the preconcentration column. Inline calibration minimizes the anion contamination.

Determination of acetate, chloride, nitrite, bromide, nitrate, phosphate, sulfate, oxalate, fumarate, and molybdate using anion chromatography with conductivity detection after chemical suppression.

Determination of fluoride, formate, chloride, nitrite, bromide, nitrate, sulfate, oxalate, and molybdate in a coolant using anion chromatography with conductivity detection after chemical suppression and Metrohm Inline Dialysis.

Partial loop injection is a well known way of sample introduction to HPLC. In ion chromatography it is not yet used to a large extent. Liquid handling with Metrohm's Dosino technology now enables to use partial loop injection on a highly reproducible and accurate level. It includes multi-level calibration out of one standard solution. This AN shows its use for parallel anion and cation determination in tap water applying one single Sample Processor. The cation results are shown in Applicatin Note C-133.

The state-of-the-art tri-chamber suppressor technology provides a fresh suppressor chamber for each measurement. The complete regeneration of the chamber after each sample ensures highly efficient cation exchange – today, tomorrow, and even after years of continuous operation. The chromatograms as well as the statistical data demonstrate the outstanding reproducibility of the measurements with the Metrohm Suppressor Module.

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

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

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

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

The determination of anions in tap water is a simple IC application. Here it is used to present Metrohm's intelligent Pick-up Technique (MiPuT). MiPuT enables the injection of volumes of minimum size from very small sample quantities. In the present case, two volumes of 10 µL from a sample 100 µL in size are used for anion and cation analysis, respectively. The calibration takes place through the injection of various volumes of a single standard solution. AN-C-141 describes the corresponding cation determination.

Metrohm Inline Preconcentration Technique with Matrix Elimination (MiPCT-ME) is a powerful tool that combines preconcentration, matrix elimination, and multilevel calibration. The latter only requires a single multi-ion standard solution. The 800 Dosino takes over all liquid handling tasks. The shown system setup allows sample analysis from 0.1 µg/L up to 1.0 mg/L.

Water of the water-steam cycle of boiling water reactors (BWR) needs to be free of corrosive anions. Analyzing these trace anions allows the parallel determination of chromate, which is a potential corrosion product. Automated sample preparation includes variable Inline Preconcentration (MiPCT) and automatic calibration with a single multi-ion calibration standard.

The determination of low nitrite concentrations in the presence of excess sodium chloride is demanding due to the small retention time difference of these two anions. Dual detection – conductivity and UV/VIS – is a powerful method for determining nitrite traces in a 20 g/L sodium matrix. The UV/VIS chromatogram displays no chloride interferences. The determination of ammonium traces in the presence of excess sodium is described in AN-C-145.

Cleanliness is indispensable in electronics production. Ionic contaminations in particular lead to a drastic worsening of the quality of the printed circuit boards. The present Application Note describes the determination of anions on printed circuit board surfaces. The intelligent Partial Loop Injection Technique (MiPT) used for this purpose permits the determination of cations and anions in the same sample. The determination of the cations is described in AN-C-149.

Fast IC means a high sample throughput. This is attained with short columns, relatively high flows and strong eluents. Here standard anions are determined within three minutes on the Metrosep A Supp 10 - 50/4.0.

Fast IC means short run times and a high sample throughput. This is attained using short columns and strong eluents. Fluoride, chloride, nitrate, phosphate, sulfate and oxalate are separated in less than eight minutes using the Metrosep A Supp 5 - 100/4.0.

Fast IC means short run times and a high sample throughput. This is attained using short columns and strong eluents. Drinking water (including fluoride) is analyzed on the Metrosep A Supp 5 - 100/4.0 under the same conditions as in AN-S-322.

Swimming pool water needs to be thoroughly disinfected and this is often accomplished with ozonization. This process can generate harmful oxyhalides, the concentration of which must be monitored. Here the separation and determination of oxyhalides as well as standard anions are carried out using a column of the Metrosep A Supp 5 - 250/4.0 type. Quantification takes place using conductivity detection in accordance with sequential suppression.

FDG gypsum originates from flue gas desulfurization systems in power plants. VGB-M 701 E (2008) describes aqueous extraction methods for determining chloride in FDG gypsum using ion chromatography. The sample preparation described in the VGB permits the determination of other anions besides chloride.

The Metrosep A Supp 5 microbore anion column is available in 150 and 250 mm lengths. For the two columns, the run times for separating the 7 standard anions are 20 and 29 minutes. In addition to the good separation properties and the short running times, microbore columns use approximately 75% less eluent than does their 4 mm counterpart.

The column stability of the microbore version of the Metrosep A Supp 5 - 250/2.0 was determined in long-term laboratory tests. Two injection series each were run on six days in a row. Each series was comprised of nine tap water injections, three check standard injections and six tap water injections. The IC system was shut down on the seventh day of each series. As a whole, the IC system ran over 12 weeks and counted a total of 2,650 injections. The results show an outstanding reproducibility and verify the high column stability.

The stability of the Metrosep A Supp 5 - 250/4.0 column was determined in long-term laboratory tests. Two injection series each were run on six days in a row. Each series was comprised of nine tap water injections, three check standard injections and six tap water injections. The IC system was shut down on the seventh day of each series. As a whole, the IC system ran over 10 weeks and counted a total of 2,150 injections. The results show an outstanding reproducibility and verify the high column stability.

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

4-Hydroxybutyrate (GHB) is numbered among the hydroxycarboxylic acids and is used as a psychoactive drug which is illegal in many countries. GHB can be determined through anion chromatography with suppression. GHB can be separated from the standard anions and the organic acid anions glycolate, acetate and formate on the Metrosep A Supp 16 - 250/4.0 column and under the conditions specific in this Application Note. Key words: Liquid Ecstasy, KO drops

Electronic-grade nitric acid may not contain more than the slightest traces of anion contaminations (in the mg/L range). The ion chromatography determination of these kinds of anion traces requires not only a high-capacity column but also an eluent that allows the nitrate to be eluted by the column, although only after all of the other ions of interest have been eluted. This separation is achieved on a column of the Metrosep A Supp 16 - 250/4.0 type with the aid of a strong carbonate/hydrogen carbonate eluent.

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

Microbore columns with an inner diameter of 2 mm reduce the eluent consumption to about a quarter. Consequently, the detected peak areas of corresponding sample concentration are increased by a factor 4. In this report, the determination of anions in drinking water is described on a Metrosep A Supp 5 - 150/2.0 column.

In ion chromatography with suppressed conductivity detection, calibration curves quite often are not really linear. Especially, if a calibration has to cover a large concentration range, results will be more accurate when multiple calibration curves for different concentration ranges are applied. The MagIC Net software allows to apply multiple calibration curves within one single determination. This means that for every ion the optimal calibration is applied, improving the accuracy of the results. This method is applied to rainwater samples.

Parallel anion and cation analysis is typically used when both anions and cation have to be analyzed. Here, the anion part of such an analysis is shown. The sample is injected to the anion channel from the 889 IC Sample Center by its built-in injector. The whole system is controlled by Empower applying the Metrohm IC Driver 2.0. For cation analysis, see AN-C-166.

Glycolate and lactate have to be determined in a dual phase varnish remover. Analyzed is only the upper aqueous phase. The separation is achieved on a Metrosep A Supp 16 - 250/4.0 column. The eluent composition is adapted to get a sufficient separation of glycolate and lactate without interference by formate and acetate. Conductivity detection after sequential suppression is applied.

Pyrophosphate is used as a stabilizer in aqueous hydrogen peroxide solution. “Reagent grade” solutions may contain pyrophosphate in the higher mg/L range, while “electronic grade” hydrogen peroxide should be free of this stabilizer. Here the determination of pyrophosphate in a high purity H2O2 solution (30%) is performed applying Inline Preconcentration with Matrix Elimination (MiPCT-ME) and a Dose-in Gradient.

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

Monoethylene glycol is used for dehydration of the natural gas before liquefaction and has to be checked for its purity on routine basis. Inorganic anions and their corresponding acids are corrosive. Therefore, they have to be kept at minimum level. The separation is performed on a microbore Metrosep A Supp 16 - 250/2.0 column and quantified by conductivity detection after sequential suppression.

The microbore Metrosep A Supp 4 - 250/2.0 column is particularly suitable for the analysis of anions in critical samples. A waste water sample is being analyzed in the current application. The sample requires only one filtration prior to injection on the Metrosep A Supp 4 - 250/2.0. The anions are quantified with the application of conductivity detection following sequential suppression.