Drei verschiedene Suppressorsysteme werden ionenchromatographisch evaluiert. Zudem werden verschiedene Phosphate neben mono- und divalenten Anionen mit Gradientenelution detektiert.

AN-S-152

2-Fluorobenzoat in Wasserabscheidungen

Bestimmung von 2-Fluorobenzoat in einer Wasserabscheidung aus der Erdölförderungs-Industrie mittels Anionenchromatographie und anschliessender Leitfähigkeitsdetektion und chemischer Suppression.

AN-S-149

Anionen in Tripolyphosphat

Bestimmung von Chlorid, Nitrit, Nitrat, Phosphat, Sulfat, Trimeta- und Pyrophosphat in Tripolyphosphat mittels Anionenchromatographie mit einem Hochdruckgradienten und anschliessender Leitfähigkeitsdetektion nach chemischer Suppression.

AN-S-148

Anionen in Tetranatrium-Pyrophosphat

Bestimmung von Fluorid, Chlorid, Nitrat, Phosphat, Sulfat, Trimetaphosphat und Tripolyphosphat in Tetranatrium-Pyrophosphat mittels Anionenchromatographie mit einem Hochdruckgradienten und anschliessender Leitfähigkeitsdetektion nach chemischer Suppression.

AN-S-147

Zehn Anionen in einem Explosivstoffextrakt

Bestimmung von Chlorid, Nitrit, Cyanat, Azid, Nitrat, Chlorat, Sulfat, Thiocyanat, Thiosulfat und Perchlorat in einem Explosivstoffextrakt mittels Anionenchromatographie und anschliessender Leitfähigkeitsdetektion nach chemischer Suppression.

AN-S-146

Chlorid und Sulfat in Bernsteinsäure

Bestimmung von Chlorid und Sulfat in Bernsteinsäure mittels Anionenchromatographie und anschliessender Leitfähigkeitsdetektion nach chemischer Suppression.

AN-S-145

Chlorid und Sulfat in Hypophosphorsäure

Bestimmung von Chlorid und Sulfat in Hypophosphorsäure mittels Anionenchromatographie und anschliessender Leitfähigkeitsdetektion nach chemischer Suppression.

AN-N-034

Sulfat in Gips

Bestimmung von Sulfat in Salzsäure nach Aufschluss von Gips mittels Anionenchromatographie und anschliessender direkter konduktometrischer Detektion.

AN-N-033

Fluorid und Chloird in Gips

Bestimmung von Fluorid und Chlorid in Gips mittels Anionenchromatographie und anschliessender direkter konduktometrischer Detektion.

AN-N-028

Bromidspuren in Salzsäure (32%) mittels amperometrischer Detektion

Bestimmung von Bromidspuren in HCl (32%) mittels Anionenchromatographie und anschliessender amperometrischer Detektion mit einer Silberelektrode.

AN-N-015

Bestimmung von Pyrophosphat, Tripolyphosphat und Trimetaphosphat

Bestimmung von Pyrophosphat, Tripolyphosphat und Trimetaphosphat mittels Anionenchromatographie und anschliessender direkter Leitfähigkeitsdetektion.

AN-H-095

Determination of urea by non-aqueous titration

Dissolution of urea in glacial acetic acid, and titration with standard 0.1 mol/L trifluoromethanesulfonic acid in acetic acid using isobutyl vinyl ether as a thermometric endpoint indicator.

AN-C-131

Magnesium, cadmium and iron in phosphoric acid

Determination of magnesium, cadmium and iron in phosphoric acid using cation chromatography with direct conductivity detection.

AN-C-053

Bestimmung von Magnesium und Barium in Anwesenheit von grossen Kalziummengen

Bestimmung von Magnesium und Barium in Anwesenheit von grossen Kalziummengen mittels Kationenchromatographie und anschliessender direkter Leitfähigkeitsdetektion.

AN-C-037

Lithium, Natrium und Ammonium in Lithium-Hexafluorophosphat

Bestimmung von Lithium, Natrium und Ammonium in Lithium-Hexafluorophosphat mittels Kationenchromatographie und anschliessender direkter Leitfähigkeitsdetektion.

AN-C-031

Kalzium und Magnesium in hochreinem Natriumchlorid

Bestimmung von Kalzium und Magnesium in hochreinem Natriumchlorid mittels Kationenchromatographie und anschliessender direkter Leitfähigkeitsdetektion.

AB-316

Determination of phosphoric acid in liquid fertilizer with 859 Titrotherm

The phosphoric acid content can be easily titrated with a standardized solution of 2 mol/L NaOH. The interfering calcium content in phosphoric fertilizer can be eliminated by adding a saturated oxalate solution.

AB-314

Determination of total phosphate in phosphoric acid and phosphate fertilizers with 859 Titrotherm

Phosphate can be rapidly and easily titrated thermometrically using a standard solution of Mg²⁺ as titrant. The phosphate-containing solution is basified and buffered with NH₃/NH₄Cl solution before titration. The formation of insoluble MgNH₄PO₄ is exothermic. The method is a titrimetric adaptation of a classical gravimetric procedure.

This bulletin deals with the determination of phosphate in phosphoric acid and granular fertilizers such as MAP (monoammonium phosphate), DAP (diammonium phosphate) and TSP (triple superphosphate). Results are reported as percentage of P and P₂O₅.

AB-308

Determination of sulfate in phosphoric acid (liquid fertilizer samples) with 859 Titrotherm

AB-307

Determination of sulfate in granular phosphate fertilizers with 859 Titrotherm

Sulfate can be rapidly and easily titrated thermometrically using a standard solution of Ba²⁺ as titrant. In industry, the widespread procedure is applied to the determination of sulfate in wet-process phosphoric acid. This bulletin deals with the determination of sulfate in granular fertilizers such as MAP (monoammonium phosphate), DAP (diammonium phosphate) and TSP (triple superphosphate). Results are reported as percentage of elemental sulfur, %S.

8.000.6060EN

Voltammetric determination of iodide in brine used in chlor-alkali electrolysis

In this study, we developed a straightforward and sensitive method for the trace determination of iodide in brine used for chlor-alkali electrolysis. The method involves the oxidation of iodide to iodate and the subsequent determination of the iodate by differential pulse voltammetry. The quantitative iodide conversion to iodate is achieved by treatment with sodium hypochlorite. After 20 minutes reaction time, excess hypochlorite is removed by adding sodium sulfite. Interfering metal traces are complexed by EDTA addition.

The described differential pulse voltammetric method for the determination of iodide in brine has significant advantages over other commonly employed methods. Besides the excellent price-performance ratio, the voltammetric iodide determination excels by its sensitivity, selectivity and high degree of matrix independence.

8.000.6033EN

Analysis of energetic materials in various water and soil samples using HPLC and LC-MS

In modern days, a new breed of energetic (explosive) materials is emerging. Traditional aromatic nitrates are still in use, but there is dire need of analytical techniques for energetic materials in the chemical class of peroxides, azo etc. This presentation will demonstrate the use of a modern HPLC system with traditional detector (DAD) and also coupled with mass spectrometry for the analysis of abovementioned various classes of energetic materials.

8.000.6016EN

Advantages of multidimensional ion chromatography for trace analysis

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.