Biohydrometallurgy as an environmentally friendly approach in metals recovery from electrical waste: A review

Nowadays, large amount of municipal solid waste is because of electrical scraps (i.e. waste electrical and electronic equipment) that contain large quantities of electrical conductive metals like copper and gold. Recovery of these metals decreases the environmental effects of waste electrical and electronic equipment (also called E-waste) disposal, and as a result, the extracted metals can be used for future industrial purposes. Several studies reported in this review, demonstrated that the biohydrometallurgical processes were successful in efficient extraction of metals from electrical and electronic wastes. The main advantages of biohydrometallurgy are lower operation cost, less energy input, skilled labour, and also less environmental effect in comparison with pyro-metallurgical and hydrometallurgical processes. This study concentrated on fundamentals and technical aspects of biohydrometallurgy. Some points of drawbacks and research directions to develop the process in the future are highlighted in brief.