Formation of Black Droplets from Coal Biosolubilization

To study mechanisms of coal biosolubilization, this paper investigated the formation of black droplets on the surface of Sabouraud maltose agar (SMA) culture media through coal solubilisation by Hypocrea lixii AH. The black droplets were collected and weighted. Mycelia of Hypocrea lixii AH were characterized by (Full name is required before abbreviation) FTIR spectra and contact angles. The results showed that the first 9 days are black droplets permeation period, solubilized coal in coal pole keep place due to increase of polarity with mycelia aging. Moisture content of the black droplets was 96.4(±0.2) %, largely resulting in high-polarity property of the black droplets. Furthermore, the comparison on moisture contents of coal and black droplets indicated that the water content of black droplets were from the culture media and bio-oxidation instead of coal self.

Status of Coal Biotechnology in Pakistan

Pakistan is endued with 185 billion tons colossal reserves of coal, but only 7.89 % of the country total energy requirements are met by coal. Most of the Pakistani coal reserves are sub-bituminous or lignitic in nature and contain 3-12 % sulphur. Existence of sulphur compounds in coal limits its industrial application due to environmental as well as technical problems. However, coal biotechnology can emerge as panacea for upgrading the huge reserves of coal in Pakistan. In general, coal biotechnology refers to biodesulphurization, biosolubilization and biogasification of coal. NIBGE has long term interests in the field of coal bioprocessing for tapping prime resources of indigenous coal. In NIBGE, lab scale experiments for coal biodesulphurization led to 90% efficiency in sulphur removal. Heap leaching was also carried out at the level of 10 and 20 tons coal heaps with 60% sulphur removal efficiency. Furthermore, a prototype of 300 tons coal heap was set up with a local cement industry and 75% microbial desulphurization was achieved. The league of indigenously isolated chemolithotrophic bacteria was involved in coal desulphurization. On the other side, for making the best use of 175 billion tons of low rank coal reserves, coal biosolubilization and subsequent biogasification is being projected. Consequently, beneficiated coal through biotechnology is supposed to contribute in energy mix of Pakistan for providing electricity requirements of the country and saving huge oil import bills.