Improved performance of SO2 depolarized electrolyser with non-fluorinated and bio-based cellulose membranes

SO 2 depolarized electrolyser (SDE) is a type of proton exchange membrane electrolyser that oxidizes SO 2 while simultaneously producing hydrogen at a lower potential which could aid industrial decarbonization. A non-fluorinated cellulose-based Cellfion membrane is evaluated against Nafion-117 and Vanadion 20 membrane for its performance in SDE over a period of two days. Energy demand for hydrogen production of the cell with Vanadion membrane is the highest, followed by Nafion, and Cellfion has the lowest. A long-term stability test of 15 h is conducted for the Cellfion membrane shows that the energy demand for hydrogen production was stable whereas a slightly decreasing trend is observed for Nafion. Nevertheless, both required lower energy than conventional water electrolysis providing an opportunity to implement SDE on an industrial scale. The study concludes that cellulose-based membranes can perform at par with or better than Nafion-based membranes. • Non-fluorinated cellulose-based membrane has excellent performance in SDE. • New method presents energy demand for gas production based on electrochemical data. • Most membranes showed lower energy demand compared to traditional PEM electrolysis. • Promising results with improved membrane to achieve industrial grade hydrogen.