Fungal biotransformation of anthracite-grade carbonaceous matter: Effect on gold cyanide uptake
Carbonaceous matter ( CM) present in refractory carbonaceous gold ores adsorbs dissolved gold during cyanidation, leading to a decrease in gold recovery. In an on-going study the fungus Phanerochaete chrysosporium has been shown to reduce the gold adsorption ability of anthracite-grade CM by more than 90％ in a mixture of millet and wheat bran medium. The present study thus focused on establishing the set of incubation parameters responsible for maximum reduction in gold adsorption by anthracite-grade CM. Anthracite coal was used as surrogate for CM, and the results indicate that P. chrysosporium deactivates anthracite within a wide range of time, pulp density, temperature, pH, and level of agitation. A processing time of 4 -7 days at pH 4 and 371 gave the best conditions. The best pulp densities for stationary and shake culturing respectively were 60％ and 25％ . Analyses of the anthracite material using XANES spectroscopy showed an increase in the amount of oxygen-containing groups such as carboxyls and carbonyls. In addition, BET surface area and micropore volume decreased by 76％ and 80％ respectively, whereas average pore diameter increased by 65％. The results suggest that P. chrysosporium biotransforms anthracite by surface oxidation, which leads to a decrease in C/0 ratio and disruption of the continuous graphitic structure, thus decreasing the active sites necessary for adsorption.
fungi biotransformation incubation parameters carbonaceous matter aurocyanide adsorption
Grace Ofori-Sarpong Kwadwo Osseo-Asare Ming Tien
Department of Mineral Engineering, University of Mines and Technology,P. O. Box237,Tarkwa, Ghana Department of Materials Science and Engineering,and Department of Energy and Mineral Engineering Department of Biochemistry and Molecular Biology,Penn State University, University Park, PA 16802, U
国际会议
The 19th International Biohydrometallurgy Symposium(第19届国际生物湿法冶金大会 IBS2011)
长沙
英文
445-451
2011-09-18（万方平台首次上网日期，不代表论文的发表时间）