Microorganisms in Coal Desulfurization (Review)

The information on the use of microorganisms and mixed consortia in the biological desulfurization of coal is summarized. The ecological problems that accompany the burning of high-sulfur coals are shown, and the prospects of environmentally friendly and resource-saving biotechnological approaches to coal desulfurization are considered. Analysis of available literature indicates the enormous role of microorganisms of various taxonomic groups in the removal of inorganic and organic sulfur in coals. Mesophilic and moderately thermophilic acidophilic chemolithotrophic bacteria (ACB) of the genus Acidithiobacillus—A. ferrooxidans, A. thiooxidans, A. caldus, as well as some heterotrophic bacteria Bacillus subtilis and paenibacillus polymyxa—play the dominant role in the removal of inorganic sulfur. Mixed cultures and associations of mesophilic and thermophilic bacteria isolated from coal mines or from the coal surface structure are considered an effective tool in the biosulfurization of pyrite sulfur. The prospects of microbial desulfurization of organic coal sulfur with the use of heterotrophic microorganisms of the genera Pseudomonas, Sulfolobus, Rhodococcus, the fungi Agrocybe aegerita and Alterneria sp., the bacterial–fungal consortia Sulfolobus solfataricus and Phanerochaeta chrysosporium ME446, and the laccase enzyme of the basidiomycetes Trametes versicolor ATCC 20080 are examined.