Biomining is nowadays an emerging technology of bioremediation as well as resource recovery. Acidithiobacillus ferrooxidans is a gram (-), obligate chemoautotrophic bacteria which is capable of oxidation of metal sulfides like FeS, ZnS etc, thus capable of recovering heavy metals from mining wastes as well as industrial sludge. This study has focused on Zn recovery from the sludge of electroplating industry. Experimental observation reveals that after 7, 14 and 21 days of incubation under shaking and static condition in media containing pure ZnS and ZnS recovered from sludge, maximum efficiency of the bacteria has been found under shaking condition after 21 days of incubation from pure ZnS (45.4%) in comparison to ZnS recovered from the electroplating industrial sludge (26.2%) which indicates that as A ferrooxidans is an aerobic bacteria thus maximum bioleaching efficacy depends on aeration, optimum condition, number of bacterial cells in the culture media and purity of metal sulfide.
