ISO/TC 27/SC 5/WG 2 - Carbon, hydrogen, nitrogen, oxygen and sulfur

This document establishes a practice for the ultimate analysis of coal and coke and is intended for general utilization by the coal and coke industries to provide a basis for comparison of coals and cokes.

This document specifies a reference method for determining the total sulfur content of hard coal, brown coals and lignites, and coke by the Eschka method.

This document specifies a method of determining the chlorine content of hard coal, brown coals and lignites, and coke using Eschka mixture.

This document specifies two methods (high temperature combustion and high pressure vessel combustion) for the determination of chlorine in solid mineral fuels. It is applicable to solid mineral fuels. The chlorine in the absorption solution can be determined using different finishes, such as coulometric or potentiometric titration, spectrophotometry or ion chromatography. The method is applicable to determine the chlorine content higher than 0,005 % mass fraction.

This document specifies a gravimetric method of determining the carbon in the mineral carbonates associated with solid mineral fuels. NOTE The result obtained will include any carbon from atmospheric carbon dioxide absorbed by the fuel.

ISO 20336:2017 specifies an alternative method of determining the total sulfur content of coal and coke by high-temperature combustion ? Coulomb titration.

ISO 19579:2006 specifies an alternative method of determining the total sulfur content of hard coal, brown coal, and lignite by high-temperature combustion and infrared absorption using commercially available instruments. This method has been shown to be applicable to coal samples having an ash yield of less than 40 %.

Specifies methods of determining the sulfate and pyrite sulfur contents of coals, including brown coals and methods of calculating the amount of organic sulfur present. Replaces the first edition.

Specifies a method of the determination of the total carbon and the total hydrogen of hard coal, brown coal, lignite and coke by a high temperature combustion method.

Specifies a method of the determination of the total carbon and the total hydrogen of hard coal, brown coal, lignite and coke by the Liebig method.

ISO/TS 18806:2014 specifies two methods (high temperature combustion and bomb combustion) for the determination of chlorine in solid mineral fuels. It is applicable to hard coals, brown coals, coke, and tailings. The chlorine in the digestion solution can be determined using different methods, e.g. an ion-selective electrode, coulometric or potentiometric titration, spectrophotometry, or ion chromatography. In this Technical Specification, the ion chromatographic separation with conductivity detection is described. The method is applicable to determine the chlorine content higher than 0,005 per cent mass fraction.

ISO 334:2013 specifies a reference method for determining the total sulfur content of hard coal, brown coals and lignites, and coke by the Eschka method.

ISO 17247:2013 establishes a practice for the ultimate analysis of coal and is intended for general utilization by the coal industry to provide a basis for comparison of coals.

ISO 17247:2005 establishes a practice for the ultimate analysis of coal and is intended for general utilization by the coal industry to provide a basis for comparison of coals.

ISO/TS 11725 specifies a method of determining the nitrogen content of hard coals, brown coals and lignites, cokes and chars by a semi-micro gasification method.

Specifies a method of determining the nitrogen content of hard coal, brown coal and lignite by the semi-micro Kjeldahl method. Replaces the third edition.

Gives a method of the determination of the total sulfur content of hard coal, brown coal, lignite and coke by a high temperature combustion method. Replaces the second edition.

The reference method specified is based on igniting a test portion (of hard coal, brown coal, lignite, or coke) in intimate contact with Eschka mixture in an oxidizing atmosphere, removal of combustible matter and conversion of the sulfur to sulfate, extraction of sulfate with hydrochloric acid solution and gravimetric determination by precipitation with barium chloride.

The sample is burnt in a stream of oxygen, in a tube furnace at a temperature of 1250 or 1350 °C, and the acid gases (chlorine and oxides of sulphur) formed are absorbed in hydrogen peroxide. The acid solution is neutralized with sodium tetraborate and the sodium chlorine formed is converted by reaction with mercury(II) oxycyanide to sodium hydroxide which is determined volumetrically.