Volume No. 9 Issue No.: 1 Page No.: 209-215 July-September 2014

 

BIO-PROCESSING OF INDIAN COALS BY MICROORGANISMS : AN INVESTIGATION

 

Manoj B.

Department of Physics, Christ University, Hosur Road, Bangalore (INDIA)

 

Received on : January 10, 2014

 

ABSTRACT

 

Cultures of filamentous fungi, Aspergillus niger and Penicillium spp, developed for bio leaching of subbituminous coal in modified Czepek Dox medium with low sucrose. The changes in the mineral matter composition of the coal sample were evaluated using Scanning Electron Microscopy (SEM) with Energy Dispersive Spectrograph (EDS). The coal sample leached with A. niger decreased the ash content from 12.87 wt% to 0.55 wt% by mainly removing Al and Si containing minerals. Leaching with Penicillium sp. decreased the ash content to 3.05 wt% and with mixed culture, ash content was reduced to 1.21 wt%. Calorific value of the coal samples showed an increase of 27% following A. niger leaching. The High Performance Liquid Chromatography (HPLC) analysis revealed the production of various low molecular weight organic acids mainly acetic acid, citric acid and gluconic acid during bioleaching which leads to lowering of pH of the media and hence removal of silicate and aluminum minerals.

 

Keywords : Biodegradation, Coal characterization, Organic acid, HPLC, SEM/EDS

 

 

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