Extended petroleum hydrocarbon bioremediation in saline soil using Pt-free multianodes microbial fuel cells

Abstract

Bioelectrochemical remediation is an emerging technology for in situ removal of petroleum hydrocarbons in soil. Here we demonstrated that the remediation can be extended to a larger range by adding multilayer anodes in contaminated soils. Using a three anodes system with activated carbon as the cathodic catalyst, 918 C of charge transferred during 180 days in aged saline soil. The degradation of both polycyclic aromatic hydrocarbons (PAHs) and n-alkanes were accelerated in each layer compared to the disconnected control. The net degradation rates of total petroleum hydrocarbons, 16 priority PAHs and total n-alkanes (C8–C40) were 18%, 36% and 29%, respectively. Popular exoelectrogens (such as Geobacteraceae sp.) and Escherichia were identified, which possibly played an important role in this bioelectrochemical process.