FUNGAL ATTACK ON COAL - I - MODIFICATION OF HARD COAL BY FUNGI

Within a screening program more than 750 fungal strains were tested fo r their ability to attack a German hard coal (Westerholt Mine). Six st rains were selected, which modified the physicochemical properties of hard coal pieces placed on the overgrown surface of Petri dishes (loss of the compact coal structure, 'erosion,' increase in wettability). O ne of these strains, Coprinus sclerotigenis C142-1, liberated 2-hydrox ybiphenyl, alkylated benzenes and polycyclic aromatic hydrocarbons (PA H) from powdered hard coal. It is presumed that most of these compound s were liberated from micropores inside of the hard coal macromolecule . Investigations using hard coal derived asphaltenes indicate that the liberation of hydroxylated biphenyls by C. sclerotigenis is due to a real cleavage of chemical bonds. The cultivation of the white-rot fung us Panus tigrinus on wood shavings coated with asphaltenes led to a de crease of the average molecular weights of these hard coal-derived hyd rogenation products. Published by Elsevier Science B.V.