The concentration of Fe(total) in boiler feed water is determined by adsorptive stripping voltammetry (AdSV) with 2,3-dihydroxy-naphthalene (DHN) as complexing agent. All reagents have to be added in the order as listed below. All reagents typically contain iron impurities, especially the DHN. Therefore a subtraction of the reagent blank is recommended.

AN-T-027

Alkalinity of amine-containing gas washing solutions

Determination of the alkalinity of gas washing solutions containing alkanolamines by potentiometric titration with sulphuric acid using the combined glass electrode.

AN-S-250

Trace anions in tetramethylammonium hydroxide (TMAOH)

Determination of formate, chloride, nitrate, phosphate and sulfate in 20% TMAOH using anion chromatography with conductivity detection after sequential suppression and Inline Matrix Neutralization.

AN-S-242

Trace analysis of anions in the primary cycle of a nuclear power plant (PWR) using Metrohm Inline Sample Preparation

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.

AN-S-228

Anions in perfluorocarbon

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

AN-S-222

Anions in borate effluent

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

AN-S-218

Common anions in a closed cooling water system

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

AN-S-158

Five anions in the presence of 2 g/L nitrate in an ion exchanger eluate

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.

AN-S-157

Trace anions in boiler feed water containing 10 mg/L ammonia

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.

AN-S-066

Trace anions in boric acid after preconcentration

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

AN-S-056

Traces of chloride in ultrapure water under clean room conditions

Determination of traces of chloride in ultrapure water with direct injection under clean room conditions using anion chromatography with conductivity detection after chemical suppression.

AN-S-053

Four anions in boric acid

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

AN-S-032

ppt analysis (ng/L) in ion chromatography

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

AN-S-028

ppb levels of anions

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.

AN-S-005

Six anions in cooling water

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

AN-Q-003

Online monitoring of trace levels of anions in boiler feed water

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

AN-Q-002

Online monitoring of trace levels of cations in boiler feed water

Determination of trace levels of lithium, sodium, ammonium, potassium, magnesium and calcium in boiler feed water using cation chromatography with direct conductivity detection.

AN-Q-001

Online monitoring of trace levels of silicate in boiler feed water

Determination of trace levels of silicate in boiler feed water using anion chromatography with direct conductivity detection.

AN-N-065

Borate in borate effluent

Determination of borate in a borate effluent using anion chromatography with direct conductivity detection.

AN-N-060

Online monitoring of trace levels of silicate in boiler feed water

Determination of trace levels of silicate in a boiler feed water using anion chromatography with direct conductivity
detection.

AN-M-001

Aliphatic monocarboxylic acids in produced water using IC/MS coupling

Determination of acetic, propionic, butyric, valeric and caproic acid in produced water using anion chromatography with conductivity and MS detection after post-column addition of ammonia for MS detection and inline sample preparation by dialysis.

AN-K-010

Water in coal dust

The water content of coal dust is determined according to Karl Fischer. Because of the low water content of the voluminous sample the oven method (nitrogen, 270 °C) and coulometric titration have to be used.

AN-H-012

Determination of ferrous ion content of heat exchanger wash solutions

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

AN-C-096

Trace analysis of monovalent cations in an ethanolamine matrix (secondary cycle of a pressurized water reactor) using Metrohm Inline Sample Preparation with an 800 Dosino for liquid handling

Methylamine (MMA), dimethylamine (DMA) and trimethylamine (TMA) in methylpyrrolidone using Metrohm Inline Matrix Elimination.

AN-C-094

Methylamine, isopropylamine, diethylamine and diethylethanolamine with preconcentration

Determination of traces of methylamine, isopropylamine, diethylethanolamine and diethylamine using cation chromatography with direct conductivity detection.

AN-C-090

Traces of zinc and iron (II) in the presence of the standard cations

Determination of traces of zinc and iron(II) in the presence of lithium, sodium, ammonium, potassium, calcium and magnesium in boiler water using cation chromatography with direct conductivity detection.

AN-C-083

Online monitoring of trace levels of cations in boiler feed water

Determination of trace levels of lithium, sodium, ammonium, potassium, magnesium and calcium in boiler feed water using cation chromatography with direct conductivity detection.

AN-C-078

Ethanolamines in the presence of alkali metal and alkaline earth cations

Determination of mono-, di- and trimethanolamine (MMA, DMA, TMA respectively), in the presence of lithium, sodium, ammonium, potassium, magnesium, cesium, calcium and strontium using cation chromatography with direct conductivity detection.

AN-C-076

Sodium and ammonium in 25% DEA (diethanolamine)

Determination of sodium and ammonium in 25% DEA (diethanolamine) using cation chromatography with direct conductivity detection.

AN-C-075

Sodium and ammonium (2000 : 1) in the presence of standard cations

Determination of sodium and ammonium with a concentration ratio of 2000 to 1 in the presence of lithium, potassium, calcium and magnesium using cation chromatography with direct conductivity detection.

AN-C-052

Determination of cations and ethanolamines

Determination of lithium, sodium, ammonium, ethanolamine (MEA), diethanolamine (DEA), potassium, triethanolamine (TEA), N-methlydiethanolamine (MDEA), calcium and magnesium using cation chromatography with direct conductivity detection.

AN-C-049

Trace cations in power plant feed water stabilized with 7 ppm monoethanolamine (MEA)

Determination of zinc, lithium, cobalt, sodium, ammonium, potassium, manganese, magnesium and calcium in power plant feed water stabilized with 7 ppm monoethanolamine using cation chromatography with direct conductivity detection.

AN-C-038

Five cations in 4% boric acid

Determination of sodium, ammonium, potassium, calcium and magnesium in 4% boric acid using cation chromatography with direct conductivity detection.

AN-C-023

Sodium, ammonium, diethanolamine, diglycolamine and potassium in wastewater

Determination of sodium, ammonium, diethanolamine, diglycolamine and potassium in wastewater using cation chromatography with direct conductivity detection.

AN-C-015

Five cations in high-pressure steam

Determination of sodium, ammonium, potassium, calcium and magnesium in high pressure steam using cation chromatography with direct conductivity detection.

AN-C-007

Determination of monoethanolamine, diethanolamine and triethanolamine

Determination of sodium and ethanolamines using cation chromatography with direct conductivity detection.

AN-C-002

Sodium, potassium, calcium and magnesium in cooling water

Determination of sodium, potassium, calcium and magnesium in cooling water using cation chromatography with direct conductivity detection.

AB-243

Determination of chromium at the Ultra Trace graphite electrode by cathodic stripping voltammetry

The method described allows traces of chromium in the range 1...250 µg/L (ppb) to be determined. It is based on the adsorption of a Cr(III)-diphenylcarbazonate complex at the Ultra Trace graphite electrode. Other organic constituents in the sample (such as could occur in natural waters) interfere considerably with the determination. For this reason they must first be eliminated, e.g. by UV digestion. The determination is carried out by adsorptive stripping voltammetry according to the DC method. It is not necessary to degas the sample solution. The determination also works for samples with a high concentration of inorganic salts.

AB-209

Coulometric water determination according to Karl Fischer in insulating oils as well as in hydrocarbons and their derivatives

Only coulometric Karl Fischer titration can determine low water contents with sufficient accuracy. This Bulletin describes the determination of water traces in insulating oils, hydrocarbons, transformer and turbine oils, etc.

AB-083

Determination of sodium with the ion-selective electrode

The determination of sodium with the sodium ISE represents a selective, rapid, accurate and favorably-priced method which is described in this Bulletin. Examples are used to show how determinations can be carried out with the 692 pH/Ion Meter using either direct measurement or the standard addition technique. The sodium concentration has been determined in standard solutions, water samples (tap water, mineral water, wastewater), foodstuffs (spinach, baby food) and urine. The construction, working principles and areas of application of the two Metrohm ion-selective sodium electrodes – the 6.0501.100 Glass membrane ISE and the 6.0508.100 Polymer membrane ISE – are explained in detail.

AB-066

Potentiometric determination of boric acid

The boric acid content in the primary cooling system of light water reactors can be determined potentiometrically. In pressure reactors boric acid is used as a safety reserve when the reactor is switched off. In addition, boron is used to compensate the difference in reactivity and, more recently, for output regulation.

In the potentiometric determination of boric acid this is treated with a polyvalent alcohol. The complex compound formed behaves like a monovalent medium-strength acid and can be titrated with sodium hydroxide.

AB-045

Colorimetric determination of silicic acid

The determination of silicic acid is important for both mineral waters (spa waters) and normal water supplies (percolating groundwaters). The content of silicic acid is particularly important for thermal power plants, in which the maximum silica content in boiler feed water must not be exceeded owing to the volatility of this impurity.

The classical gravimetric method of analysis is time-consuming and requires a sample of several liters. The method given in the «Deutsche Einheitsverfahren» requires colloidal silicic acid to be digested by sodium carbonate. Fresenius and Schneider have published a method in which a hydrofluoric/perchloric acid mixture reacts in the cold with quantities of silicic acid which will not react with ammonium molybdate after sodium carbonate treatment.

AB-044

Colorimetric determination of boron

This Bulletin describes a colorimetric method for the determination of boron with the aid of curcumin, when boron is present in very small quantities.