Study on occurrence of sulfur in different group components of Xinyu clean coking coal

Abstract

This paper illustrates the occurrence and distribution of sulfur in coal from the perspective of composition and structure of the coal body. With the organic sulfur-rich Xinyu clean coking coal as the sample, and the method of separating all group components from coal through extraction and stripping process as well as X-ray photoelectron spectroscopy (XPS) and gas chromatography/mass spectrometer (GC/MS) analysis techniques, the content of inorganic sulfur and organic sulfur of different forms in raw coal and various group components is studied and the occurrence of organic sulfur in organic matter of coal is carefully observed. The results show the distribution of inorganic sulfur is mainly dependent upon its particle size and density in coal and has less relationship with the structure of group components of coal. Thiophene sulfur is the major form of organic sulfur either in raw coal or group components. The external environment of molecules dominated by conjugated structure can decrease the electron binding energy of organic sulfur in conjugated structure, while increase that of sulfur in aliphatic structure. The distribution of organic sulfur in coal is balanced as a whole and will not be significantly influenced by structural differences of group components. However, the occurrence of organic sulfur compounds is associated with the structure of group components, showing relatively small difference. And there is only one type of small molecule organic sulfur compounds in light component, with small abundance.