Bioelectrochemical Dechlorination of 1,2-DCA with an AQDS-Functionalized Cathode Serving as Electron Donor

Abstract

In the present study we describe a simple method to immobilize the redox mediator anthraquinone-2,6-disulfonate(AQDS) at the surface of graphite electrodes, by means of acommercial anion exchange membrane. Cyclic voltammetryexperiments confirmed the efficacy of the immobilizationprotocol and the long-term (over 70 days) electrochemicalstability of the AQDS-functionalized electrode. Potentiostatic(-300 mV vs. SHE) batch experiments proved the capabilityof the electrode in accelerating the bioelectrochemicalreductive dechlorination of the groundwater contaminant1,2-dichloroethane (1,2-DCA) to harmless ethene by a mixedmicrobial culture, by serving as electron donor in the process.Considering the reported broad range of anodic and cathodicreactions catalyzed by AQDS, the herein described functionalized electrode has a remarkable potential for application inthe environmental and industrial sector.