Electrochemical reduction of COZ with high current density was studied in a CO2-methanol medium. The mole fraction of C02 in this medium varied from 0.7% to 94% with changing the pressure of the system from 1 to 60 atm. Carbon dioxide was reduced to CO, CH4, CzH4, and methyl formate at a Cu electrode. A methyl group and a formyl group of methyl formate are derived from methanol and COZ, respectively. Methyl formate production in this ...