Syed Sikandar Shah, Sandra Regina Sponchiado, Mauricio Cesar Palmieri and Denise Bevilaqua
Sao Paulo State University, Araraquara, Brazil
Posters & Accepted Abstracts: J Microb Biochem Technol
Bauxite is the main ore of aluminum (Al) and worldwide, more 95% of alumina is produced through traditional Bayer process from bauxite. To produce one ton of alumina, it needs four metric tons of bauxite and consequently generate more than two metric tons of a highly saline and alkaline bauxite residue called ā??red mudā?. Bio-hydrometallurgy is considered an alternative to the traditional Bayer process. In this study P. simplicissimum was used for the cost effective bioleaching of aluminum from bauxite. The spores of P. simplicissimum were produced using four different solid growth media. Due to the ease and simplicity in preparation, low cost and higher spore production, the oat-agar medium was chosen as the best solid growth medium. The acid production capacity of the fungus was tested using two different sources of energy including molasses and refined glucose. For the determination of the produced organic acids, High Performance Liquid Chromatography (HPLC) technique was used. The medium supplemented with molasses as a carbon substrate produced 95.60Ā±1.8 g/L of citric acid and 12.42 g/LĀ±1.2 of oxalic acid. The study was further extended for the bioleaching of Al from bauxite using the optimized conditions. Three different bioleaching approaches were established using 250mL Erlenmeyer flasks containing 100 mL of metabolite having 1% bauxite pulp density. In the direct one-step bioleaching process, 98.35% of Al was leached on the 5th day of incubation. In the direct two-step bioleaching process, 98.04% of Al was leached on 2nd day and in the indirect bioleaching process about 71.73% of Al was leached on 4th day of incubation. It was concluded that oat-agar medium can be used without any addition of sucrose or glucose for fungal sporulation and cost effective molasses can be used as a carbon substrate for organic acids production, which in turn can be effectively used for the recovery of aluminum from bauxite.
Syed Sikandar Shah is a PhD Research Scholar under the TWAS-CNPq Fellowship at the Department of Biochemistry and Chemical Technology, Institute of Chemistry, UNESP Araraquara, SP, Brazil. He is working under the supervision of Prof. Dr. Denise Bevilaqua and co-supervision of Prof. Dr. Sandra Sponchiado. He has his expertise in the fungal leaching of aluminum from the bauxite ore. Several bioleaching processes has been developed using a variety of fungal strains and different low cost carbon substrates as an energy source. Two national patents have been submitted using the fungal strains for the cost effective bio-recovery of aluminum from the bauxite ore.