Distribution and Occurrence of Arsenic in Two Typical Chinese Coals

Abstract

Two complementary methods, float-sink experiment and sequential chemical leaching were used to probe into the occurrence of arsenic in two Chinese coals: Yima (YM) and Datong (DT). Flow injection-hydride generation atomic fluorescence spectrometry was employed to measure the arsenic content in parent coals as well as the size and density-fraction samples. Float-sink experiment indicated that the heavy density fractions were enriched mineral containing arsenic in two bituminous coals studied, as confirmed by the sequential chemical leaching method. Sequential chemical leaching revealed that sulfide arsenic was the primary mode of occurrence (> 50%), stable form also abounded in coal with content between 30 and 40%, and a small amount of arsenic took the occurrence of organic form.