EAPSI: Controlling Gas Evolution and Natural Convection to Optimize the Current Distribution and Energy Efficiency of Electrochemical Cells

Chmielowiec Brian, Cambridge MA

Investigators

Abstract

Electrochemistry provides a clean and efficient way of producing structural metals at industrial scales. Electricity can be used to produce metal and oxygen or sulfur gas from raw ore whilst avoiding the emissions associated with traditional carbon coke-based production methods. This project seeks to understand how bubble evolution (whether oxygen or sulfur gas) affects the distribution of current across the anode (oxidizing electrode) in an electrochemical cell. Electrochemical engineering principles will be applied so that the results will be applicable to a wide variety of chemical systems and geometries. This research will be performed in collaboration with Professor Takayuki Homma at Waseda University and Professor Toshiyuki Nohira at Kyoto University, both of whom have great expertise with interfacial characterization. The findings will be critical designing more energy efficient electrolysis reactors. This project will utilize the high speed camera capabilities at Waseda University to observe directly the production of electrolytic bubbles and correlate the effect on the current density distribution. Magnetohydrodynamic (MHD) convection will serve as a tool to enhance mass transfer at the anode surface. Confocal laser scanning microscopy at Kyoto University will be used additionally to characterize the interfacial phenomena. Experimental results corresponding to different values of the mass Rayleigh number (Ram) relevant for metal sulfide electrolysis will be analyzed with previously developed computational methods within the Japanese labs. By developing a correlation between mass transfer and current density distribution, this project will aid in the design of more efficient electrolysis reactors with the industrial scale in mind. This award under the East Asia and Pacific Summer Institutes program supports summer research by a U.S. graduate student and is jointly funded by NSF and the Japan Society for the Promotion of Science.