Chlorine determination Eschka mixture

ISO. 2011k. Coal and Coke—Determination of Chlorine Using Eschka Mixture (ISO 587). International Standards Organization, Geneva, Switzerland. 

Determination of Chlorine in the Polymers. The chlorine content was determined by heating 0.1-1 gram of the substance to be analyzed to 700°C with a large excess of Eschka mixture. After cooling, the mass was treated with 6N nitric acid, and the chlorine present in die solution as silver chloride was precipitated, filtered, and dissolved again in an aqueous solution of ammonia. From this solution, silver was precipitated as mercaptobenzothiazolate, which allows determination of the chlorine content in the material under examination (15). 

The test for the determination of chlorine is performed by burning the coal mixed with Eschka mixture in an oxygen bomb followed by potentiometric titration with silver nitrate solution or by a modified Volhard colorimetric titration. The repeatability interval for either procedure is the same. 

Other Elements. To determine chlorine, the sample is mixed with Eschka s mixture and burned to convert the chlorine to chloride or decomposed in an oxygen bomb (18). Chloride is determined by titration (D2361) or using a chloride selective electrode (D4208) (18) (see... 

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