Applikationer

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.

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.

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.

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

This poster presents an approach that couples a Particle-Into-Liquid-Sampler (PILS) to a dual-channel ion chromatograph (IC) for measurement of aerosol anions and cations and a voltammetric measuring stand (VA) to determine the heavy metals. Feasibility of the PILS-IC-VA online system was demonstrated by collecting aerosol samples in Herisau Switzerland, at defined time intervals; air pollution events were simulated by burning lead- and cadmium-coated sparklers.

Nitrite can be determined polarographically after its conversion to diphenylnitrosamine (C6H5)2NNO. Potassium thiocyanate is used as a catalyst in order for the conversion to proceed rapidly and quantitatively. The reaction takes place in acid solution at a pH value of approx. 1.5. The limit of quantification is 5 μg/L NO2-.

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.

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 describes the determination of nitrite using thermometric endpoint titration with sulfamic acid. The nitrite content of a solution can be analyzed down to 0.2 mmol/L.

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

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

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

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.

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.

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 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 fluoride, formate, chloride, nitrite, bromide, nitrate, phosphate, and sulfate in process water using anion chromatography with conductivity detection after chemical suppression.

Determination of nitrite and nitrate in wastewater 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 chloride, nitrite, nitrate, phosphate, and sulfate in cutting oil emulsion using anion chromatography with conductivity detection after chemical suppression and dialysis for sample preparation.

Determination of fluoride, chloride, nitrite, nitrate, and sulfate in rainwater 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 chlorite and nitrite using anion chromatography with amperometric detection at the carbon paste electrode 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 chloride, nitrite, bromide, nitrate, and sulfate in water for infusion solution production using anion chromatography with conductivity detection after chemical suppression.

Determination of chloride, nitrite, nitrate, phosphate, and sulfate in an electroplating bath after inline elimination of heavy metals by cation exchange on the 793 IC Sample Prep Module 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.

As is well known, in non-suppressed ion chromatography a system peak appears after every sample injection. The same is true for suppressed ion chromatography. Here the system peak is usually much smaller but nevertheless may interfere severely with ions of interest. In some cases the operator is not even aware that a peak of interest is hidden by the system peak.The origin of the system peak as well as the factors influencing its size and position are still under discussion. The two main effects are:- the system peak elutes at the elution time of the eluent anion - the size of the system peak depends on the sample matrixKnowing the position of the system peak with different types of columns allows you to select the columns according to the needs of your application.

Determination of chloride, nitrite, nitrate, phosphate, and sulfate in a meat extract (Na2B4O7) after Carrez clearing 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 nitrite, nitrate, sulfite, and sulfate in wastewater containing high levels of chloride using anion chromatography with conductivity detection after chemical suppression and after inline chloride removal.

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 chloride, nitrite, cyanate, azide, nitrate, chlorate, sulfate, thiocyanate, thiosulfate, and perchlorate in an extract of explosives using anion chromatography with conductivity detection after chemical suppression.

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

Determination of 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 chloride, nitrite, nitrate, and sulfate in cooling lubricants using anion chromatography with conductivity and UV detection (230 nm) after chemical suppression and inline sample preparation by dialysis.

Determination of nitrite and nitrate in a plant extract using anion chromatography with conductivity detection after chemical suppression.

Determination of chloride, nitrite, nitrate, and sulfate in betaine 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, 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 chloride, nitrite, nitrate, phosphate, and sulfate in a strongly alkaline solution using anion chromatography with conductivity detection after chemical suppression.

Determination of chloride, nitrite, and sulfate in a used zinc bath using anion chromatography with conductivity detection after chemical suppression.

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