ELECTROCHEMICAL REDUCTION OF CARBON DIOXIDE TO FORMATE IN ACID ELECTROLYTE IN ACETYLENE BLACK GAS DIFFUSION ELECTRODE WITH A LEAD CATALYST

Abstract

The possibility of electrosynthesis of formate from CO2 at a current density of 50–190 mA/cm2 in sulfuric acid aqueous solutions (pH 2–2.5) in a gas diffusion electrode with a lead electrocatalyst deposited on acetylene black was studied. It is shown that with an appropriate selection of the electrolyte composition, it is possible to carry out the electrosynthesis process with parameters that practically differ little from those in alkaline solutions. The highest current efficiency of 74% was obtained at a potential of -1.89 V, a current density of 150 mA/cm2 in an electrolyte of 0.5 M K2SO4 + 0.083 M H2SO4.