Heavy metal pollution poses a long-term and serious threat to ecosystems and human health because of its high toxicity， difficulty in degradation and ease of enrichment. The harm is often chronic and cumulative， and much of the damage is irreversible. Microbial fuel cell （MFC）， as an emerging green electrochemical technology， is capable of realizing heavy metal wastewater treatment and electric energy recovery， and shows great potential in treating heavy metal wastewater generated by industries such as leather and textiles. This paper systematically reviews the research progress of MFC in heavy metal wastewater treatment in recent years， including the basic structure， treatment mechanism and electrode modification strategy of MFC. It focuses on the anode and cathode modification methods， discusses their correlation with heavy metal removal efficiency and system output power， and systematically analyzes the effects of key operating parameters such as pH value， temperature， initial concentration of heavy metal， electrode spacing， electrolyte composition， performance of ion exchange membrane， etc. on the treatment efficiency and power production performance. Finally， feasible future directions are proposed to address the current bottlenecks and the main problems in the treatment of heavy metal wastewater.

Contents

1 Introduction

2 Composition of microbial fuel cells and mechanisms for the treatment of heavy metals

3 Electrode modification

3.1 Anode modification

3.2 Cathodic modification

3.3 Anode-cathode Co-design

4 Key parameters affecting the performance of MFC in treating heavy metals

4.1 pH value

4.2 Temperature

4.3 Initial concentration of heavy metal

4.4 Battery spacing

4.5 Electrolyte composition

4.6 Performance of ion exchange membrane

4.7 Other factors

5 Conclusions and outlook