义马煤中几种微量污染元素的赋存形态研究

The mode of occurrence of trace element in coal is an important factor that influences the evolution behaviour of the element during coal conversion. In this paper, the mode of occurrence of As, Pb, Cd, Cr in Yima coal was determined using various methods including density fractionation, demineralisation and sequential chemical extraction. The results by different methods were roughly identical. Arsenic in Yima coal was found to be primarily associated with pyrite. Part of Cadmium associated with pyrite, while others with other mineral matters. Lead in Yima coal might be dispersed in many mineral matters such as sulfates, sulfides, silicates and carbonates. The mode of occurrence of Chromium was much different from other three, it was primarily associated with organic matters in Yima coal.