A sample of toluene-soluble extract from brown coal or lignite obtained by the procedure describes in ISO 975 is extracted with acetone at a temperature of 18 to 22 °C. The soluble fraction is filtered or centrifuged off and after evaporation of the solvent dried to constant mass. The percentage of acetone-soluble material is calculated from the mass of reidue after drying.
Текущий статус : WithdrawnДата публикации : 1985-12
Версия : 2
Технический комитет:Methods of analysis