Cr-methanol fuel cell for efficient Cr(VI) removal and high power production

•A novel electrochemical cell is designed for Cr(VI) removal with power production.•The power density output can reach up to 903Wm−2.•The electrochemical cell can run in a broad temperature range.•About 1.3mol methanol is consumed with per mole Cr(VI) removed. A novel Cr-methanol fuel cell was designed to remove Cr(VI) with simultaneous electricity production. In this design, methanol was oxidized on anode, while Cr(VI) was reduced on cathode. With 2molL−1 sodium hydroxide as anolyte and 0.1molL−1 sodium sulfate as catholyte, the power density output of as high as 903Wm−2 with external resistance of 15Ω at 45°C could be obtained. More than 91% Cr(VI) could be reduced in one single cycle of around 400min. What is more, the presented electrochemical cell can steadily run in wide temperature ranges from −14°C to 45°C. Our results also demonstrated that the proposed Cr-methanol fuel cell had potential application for Cr(VI) removal with simultaneous electricity production.