THE PETROLOGICAL CHARACTERISTICS AND THEIR ORIGINATION OF HIGH ORGANIC SULFUR COAL FROM GUIDIN, GUIZHOU PROVINCE

Some high organic sulfur coals exist in upper permian Coal-bearing strata in Guizhou province South-West China. Their origins have attracted high attention from geologists and coal-chemists. To study the sulfur distribution in the coals, a series of coal samples were collected from Guidin. The total sulfur content of the coal is over 11.0%. By electron microprobe analysis of desmocollinite in coal, we found that the organosulfur content is as high as 10.5%(daf base), more than 83% of total sulfur content.
Petrologically, the coal has following features, a), Desmocollinite account for greater part of macerals, with its content as high as 84%. b) Most of the desmocollinite fluorescenize brown-orange under excitation of blue light, although the coal rank is up to R₀=l.48%,c)The sizes of the most pyrite particles are very fine with their diameter about 2 μm.d) There are many pyritized microbe bodies which take the shaps of ccoi, rod, curved rod, indicating that a large amount of microbes took park in the peatification. e). Many authigenic calcite, dolomite and quartz crystals exist in the coal, f) Some caliche fossils have been discovered.
XPS analysis has been made on the bulk coal sample. We found that the molecular structures of the most organosulfur are in the form of thiophene. On the other hand, the major sulfur-containing compounds detected in extract by GC-MS Were also thiophene ring-containing components, The occurence of these compounds reminds us that they might form through addition of H₂S to double bonds of di-and/or polyunsaturated highly branched isoprenoid during peatification. This chemical imformation is useful in helping us to remove the organic sulfur from the coals.