Decontamination of multiple heavy metals-containing effluents through microbial biotechnology

MinxiWu, JingjingLiang, JieTang, GuangLi, ShipingShan, ZhaohuiGuo, LeDeng

Department of Microbiology, College of Life Sciences, State Key Laboratory of Developmental Biology of Freshwater Fish, Hunan Normal University, Changsha, Hunan, 410081, People’s Republic of China.

Abstract

To decontaminate heavy metal-containing waste water, a microbial biotechnology was developed by using the synergy between Sulfate reducing bacteria (SRB), Bacillus cereus(B. cereus) and Camellia oleifera cake (COC). In this process the COC degradation assisted by B.cereus, created an anoxic environment and provided energy and nutrition for SRB. Both of B. cereus and SRB played significant roles through biosorption, bioaccumulation and biosurfactant production. Meanwhile, a flotation technology commonly used in many effluent treatments has been led into this system for increasing the efficiency as well. After desorption and regeneration with acid and deionized water, the biosorbents could be reused to adsorb metal ions. 97% of heavy metals removal was achieved by the proposed technology. For multiple heavy metals-containing solutions, the capacities are in the order of Cd²⁺ > Zn²⁺ > Cu²⁺.

Keywords: Heavy metal removal, Bacillus cereus, Camellia oleifera cake, Sulfate reducing bacteria, Flotation.