Bioremediation of copper-containing wastewater by sulfate reducing bacteria coupled with iron

• The sulfate reduction capability of SRB was elevated by Fe0.
• The copper wastewater was treated at 25 °C.
• Cu2+ and sulfate was effectively removed in the SRB + Fe0 system.

In order to treat copper-containing wastewater effectively using sulfate reducing bacteria (SRB), iron (Fe0) was added to enhance the activity of SRB. The SRB system and the SRB + Fe0 system were operated under continuous operation. The sulfate reduction efficiency of the SRB + Fe0 system was twice as much as that of the SRB system with the sulfate loading rate at 125  mg L−1 h−1. The effect of COD/SO42− on sulfate reduction indicates an enhanced activity of SRB by adding Fe0. 99% of total sulfate was deducted in both systems at pH 4.0–7.0, and temperature slightly influenced the removal of sulfate in the SRB + Fe0 system. In the copper-containing wastewater treatment, the SRB + Fe0 system shows a better performance since sulfate removal in this system was higher than the SRB system, and the removal ratio of Cu2+ was held above 95% in SRB + Fe0 system at all influent Cu2+ concentrations.