Isolation and Screening of Coal Solubilizing Aerobic Microorganisms

Abstract

Pakistan with about 185 billion tons is known to contain sixth largest reservoir in the world. The Biosolubilization of coal is a promising technology, which converts coal into valuable added products.Recently this field is seeking increase attention owing to recent development and technology. Coal can be solubilized and transformed from solid to catalytic and liquid state by employing various coal conversion technologies. The coal fired power plant, Thermocatalysis and pyrolysis are thaught to be inefficient as modern world is shifted to more ecofriendly approach. The present research work focused on Biosolubilization of coal and involved coal solubilimnzing microorganisms isolation and screening work. Approximately 50 aerobic bacterial and fungal isolates have been isolated initially from soil,coal and water samples of Dulmiall Coal Mines,Chakwal,Pakistan. Firstly,there occurs screening step of large collection of bacterial and fungal isolates later followed by selection. The isolates were solemnly selected on the basis of their ability to grow on single carbon source. Two bacterial strains AY2, AY3 and fungal strains AY5, AY6 were shown to have effective solubilization activity on coal. The intensity of Biosolubilization was measured by determining the weight loss of the coal pieces. Coal solubilization was observed to be about 25.93% by AY2, 36.36% by AY3 and 50% by AY6. AY5 showed maximum coal solubilization (66.67%). The coal solubilizing activity of microorganisms was correlated with change in pH. Ultravoilet spectroscopy,Infrared spectroscopy and Scanning electron microscopy were performed to characterize the solubilization residues. Ultravoilet spectrum revealed increase in pattern of absorbance across all strains. The Biosolubilization products mainly contains aromatic acids, chain hydrocarbons including organic functional groups of hydroxyl, cyclane, carbonyl, ether linkage and aromatic rings. The IR spectroscopy indicates alterations of solubilized products in comparison to original coal. The evidence for the presence of microorganisms and surface erosion of coal residues in contrast to control samples were observed by means of scanning electron microscopy. Thus,there revealed, the isolated microoganisms were able to survive in coal for long period of time. Therefore present study revealed the microorganisms isolated from coal mines have enough potential solubilizing coal and can be used for different valuable products