BIOGENERATION OF IRON-BASED CATALYST PRECURSORS BY ACIDIANUS-BRIERLEYI ON HIGH-PYRITE AND LOW-PYRITE COALS FOR DIRECT LIQUEFACTION

Treatment of high-pyrite, high-sulfur Illinois (IBC) coals and pyrite- free Blind Canyon (DECS) coal with added pyrite in the presence of Aci dianus brierleyi showed formation of iron oxyhydroxide (FeOOH) particl es and subsequent sulfiding caused enhancement in liquefaction and oil yield. IBC No. 101 and 105, and DECS No. 17 containing different amou nts of pyrite were treated with A. brierleyi to evaluate its effect on FeOOH formation. Chemical analysis of the liquid phase and Mossbauer analysis of the coals revealed that all the biotreated coals showed si gnificant reduction in pyrite after 21 days (or less with pH alteratio n in the middle of IBC No. 105 coal run) of incubation. Further data o n bioprocessed coals obtained from Mossbauer spectroscopy verified the formation of an FeOOH phase, which acts as a catalyst precursor for d irect coal liquefaction (DCL). The direct Liquefaction conversion and oil yield of the biotreated DECS No. 17 coal with added pyrite increas ed by 14 and 5%, respectively, over the control which did not contain A. brierleyi.