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

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. Greater charge and a higher degradation rate of hydrocarbons in soil are obtained using a multi-anode bioelectrochemical system.