Browse

Fluorine as one of the most abundant trace elements in coals is released into the air by combustion and pyrolysis of coal. The produced fluorine gaseous compounds, particularly hydrogen fluoride, are harmful due to their toxicity to living organisms and as a source of corrosion of metallic and ceramic materials. Reliable determination of generally very low concentrations of fluorine in coal (ten to hundred ppm level) is difficult. Standard analytical methods require tedious procedures for sample decomposition and ...

Organic matter of lignites from five Tertiary deposits in the Czech Republic was studied and the general goal was to characterize a series of different coal lithotypes in relation to depositional environment from the viewpoint of organic petrology and geochemistry. Coal samples were chosen to cover various lithotypes: xylite rich coals, matrix coals, liptobioliths, and sapropelic coals. The samples differ in ash, sulphur, carbon, hydrogen, oxygen and volatile matter contents, and calorific values. Xylite rich and ...