A REVIEW OF SULPHUR IN COAL: WITH SPECIFIC REFERENCE TO THE TELKWA DEPOSIT, NORTH-WESTERN BRITISH COLUMBIA
The Jura-Cretaceous coal seams of the Currier, Mist Mountain, &thing and Gates formations generally formed in delta or strand plain environments with little marine influence. The sulphur contents of coal from these formations is therefore generally low, nearly always less than I % and often less than 0.5 %. Coalbearing formations of the Cretaceous Nanaimo and Skeena groups were deposited in coastal areas with more marine influence. Consequently sulphur contents are more variable and tend to be higher. It is therefore important to study aspects of sulphur in Cretaceous coal seams such as the seams in the Skeena Group at Telkwa (Figure I).
Influence of pyrite on hydrocarbon generation during pyrolysis of type-III kerogen
One coal sample containing type-III kerogen was selected from the Junggar Basin and investigated for gas generation using anhydrous pyrolysis either or not added pyrite at 250 °C, 300 °C, 350 °C and 400 °C for 72 h each. The gases generated in these experiments were quantitatively collected and analyzed for chemical compositions and stable isotopes of carbon. The solid residues were also quantitatively collected and analyzed for iron species using Mossbauer spectroscopy. The results showed that hydrocarbon generation from organic matters would be significantly increased by catalysis of pyrite. The produced hydrocarbons were also evaluated with the following observations: (1) the generation of gaseous hydrocarbons and bitumen can be potentially increased by 0.5–1.0 times and 0.2–1.0 times due to pyrite, respectively; (2) the peak generation of bitumen was shifted forward by 50 °C due to the catalysis of pyrite; and (3) the added pyrite was conversed into pyrrhotite and sulfur since heating temperature at 300 °C, indicating that pyrite may act indirectly as a catalytic agent and/or directly as an inducer via sulfur, and further enhance free radicals’ formation and hydrocarbons generation.
Optical Properties of Coals and Graphite
From Abstract: "Optical Properties of U.S. coals of differing rank have been investigated by the Bureau of Mines for about 20 years. These investigations have been made to further the development of an objective basis for petrographic analysis of coal and to add knowledge of the structure and composition of coal and coal components by determining their optical constants in various regions of electromagnetic spectrum."