6. Analysis of Chemical Structure of Coal and Weathered Coal by X-ray Photoelectron Spectroscopy

Abstract

X-ray photoelectron spectroscopy (XPS) was used to quantify the carbon and nitrogen forms of coals and weathered coals. In case of carbon forms, the content of carboxyl group increased as the weathering time elapsed. The increase in the carboxyl group when 74μm under coal was used was larger than that for 1mm under coal. For nitrogen forms, the content of quaternary nitrogen species increased, whereas that of pyridinic species decreased after the weathering.