Bio-electrochemical treatment of food wastewater and copper recovery from copper-contaminated plant with electricity production using biomaterial anode

摘要

A lab-based H-type microbial fuel cell (MFC) was developed for the recovery of copper (Cu) accumulated in harvested biomass ash leachate with simultaneous electricity generation and treatment of real food wastewater from cocoa processing (C1), cassava processing (C2) and bakery (C3) at low and high ionic strengths using activated wood (AW) char and activated bamboo (AB) char as anodes. The optimum Cu concentration of 85.37% and 82.14% was recovered for C1 and C3, respectively, with high ionic intensity. The least Cu (23.15%) was recorded for C2 with low ionic strength. The maximum chemical oxygen demand (COD) removal of 79.3% was obtained for C1 with high conductivity in MFCs, whereas C2 with low conductivity gave the lowest COD removal of 47.5%. Maximum power density of 249.88 mW/m~2 was attained in C1 at high ionic strength and 65.70 mW/m2 is achieved C2 with low ionic strength. AW char is a cost-effective and sustainable anode material alternative to carbon and graphite-based electrode in MFC. Findings from this study suggested MFC as a feasible low-cost and ecofriendly technology for copper recovery to limit the toxicity effects associated with disposal of harvested copper phyto-accumulated biomass with simultaneous treatment of real wastewater.