FLUORINE IN ASTURIAN COALS

Concentrations of fluorine in Asturian bituminous coals and anthracite s have been determined. Fluorine analysis has been carried out by comp aring oxygen bomb combustion and pyrohydrolysis methods. Pyrohydrolysi s revealed higher values in samples whose ash contents were greater th an 25 wt%, which in turn was related to fluorine contents higher than 100 ppm. Good correlation between fluorine and ash content suggests th at fluorine is present in these coals in mineral species, and is not p robably associated with organic matter. The association of fluorine wi th phosphorus is also discussed. An excess of fluorine concentration v ersus phosphorus, corresponding to fluorapatite, has been found.