Bioleaching of Copper from WEEE by Acidithiobacillus ferrooxidans and Acidophilic Mixtures from AMD

MSc. Solange Kazue Utimura, MSc. Carlos G.Alvarez Rosário, PhD. Jorge A.Soares Tenório, PhD. Denise C. Romano Espinosa

In this paper, the recycle of waste electric and electronic equipment (WEEE) is important to reduce the quantities of waste in landfills and attenuate the pollution in groundwater, soil and air due the contaminants and toxic substances. The advantage in recycling WEEE is that it becomes an economical option and represents a potential source of valuable metals and materials. Wastes of printed wired boards (PWBs) as a principal part of Electrical and Electronic Equipment (WEEE) and are made of metallic, polymeric and ceramic materials. Biohydrometallurgical process has been applied for extracting metals from low-grade ores and tailings. The bioleaching technologies may offer possibilities to recycling PWBs from discarded printers to recover metals, especially copper and precious metals. Previous studies were conducted with strain bacteria Acidithiobacillus ferrooxidans (A. ferrooxidans) and bacterial consortium from acid mine drainage (AMD) in bioleaching copper from PWBs. The bioleaching experiments were performed in orbital shaker at temperature 30 °C and 170 rpm with 10 % (v/v) inoculum and pulp density of 30 g/L. The copper concentration was determined by energy dispersive X-ray Fluorescence (XRF). The results showed that the copper recovery from PWBs using A. ferrooxidans was 100 % in 8 days and with a mixed culture of bacteria from AMD the copper recovery was 98 % in the same time.