Removal of Cr(VI) with Cogeneration of Electricity by an Alkaline Fuel Cell Reactor

• Published in: Journal of physical chemistry. C 2013-07, Vol.117 (28), p.14479-14484
• Main Authors: Zhang, Huimin, Xu, Wei, Wu, Zucheng, Zhou, Minghua, Jin, Tao
• Format: Article
• Language: English
• Subjects: Applied sciences; Direct energy conversion and energy accumulation; Electrical engineering. Electrical power engineering; Electrical power engineering; Electrochemical conversion: primary and secondary batteries, fuel cells; Exact sciences and technology
• ISSN: 1932-7447; 1932-7455
• DOI: 10.1021/jp400896w

Electricity can be harvested directly from an alkaline ethanol fuel cell (AEFC) reactor in which contaminant Cr(VI) is taken as the oxidant. The performance of the AEFC reactor was characterized in terms of power generation, Cr(VI) removal, cathodic efficiency, polarization curves, and Cr(VI) reduction kinetics. The cell potential, Cr(VI) removal, and cathodic efficiency are strongly dependent on pH and Cr(VI) concentration. Using 3.94 mM Cr(VI) in 1 M H2SO4 catholyte and 2.0 M C2H5OH in 0.5 M KOH anolyte, a high open circuit potential of 1.46 V and more than 96.0% Cr(VI) removal efficiency could be achieved, and in case of varying Cr(VI) concentration to 8.65 mM, a power density of 0.19 mW cm–2 at a current density of 0.23 mA cm–2 was observed. The Cr(VI) reduction follows a first-order kinetics. This work shows that the use of fuel cell provides a novel approach for simultaneous electricity generation and contaminant abatement.