Superiority Desulfurization of Indigenous Microorganisms with Sulfur Metabolism in Coal

Coal plays a vital role in energy production, but its combustion releases SO2, causing serious environmental problems. In this study, indigenous microorganisms with sulfur-metabolism potential were isolated from raw coal and evaluated for coal biodesulfurization. The isolated strain, Arthrobacter sp. DBW, degraded 50% of DBT within 100 h and reduced the total sulfur content of coal by 42%. Since pyrite remained after treatment, the sulfur removal was mainly attributed to organic sulfur removal. Mechanistic analysis indicated that Arthrobacter sp. DBW may remove organic sulfur through enzyme binding to DBT and subsequent C-S bond cleavage via the 4S pathway. In addition, partial kaolinite dissolution occurred during biodesulfurization, reducing the ash content by 1.06%. These results suggest that Arthrobacter sp. DBW has potential for organic sulfur removal from coal and may help reduce SO2 emissions during subsequent combustion.