US EPA

1161998 

Journal Article 

Electrochemical reduction of CO2 to methane in methanol at low temperature 

Kaneco, S; Yabuuchi, M; Katsumata, H; Suzuki, T; Ohta, K 

2002 

Orlando, FL 

224th ACS National Meeting 

223 

1 

U573-U573 

English 

The electrochemical reduction of CO2 on Cu electrode at 273 K was studied in various organic solvents containing dimethyl sulfoxide, N,N-dimethyl formamide, propylene carbonate, acetonitrile, ethanol, and methanol. Results dealing with the effect of the potential on the current efficiencies for the products by electrochemical reduction of CO2 on Cu in LiClO4/ethanol at 273 showed that CH4 was detected as reduction product from CO2, but the formation efficiency was < 2%. The current efficiency for hydrogen was ∼ 100%. Hence, the applied energy was wasted on hydrogen evolution instead of being used for CO2 reduction. Product distribution obtained in the electrochemical reduction of CO2 with Cu electrode in acetonitrile was similar to those in ethanol. In the acetonitrile-based electrolyte, the reduction product from CO2 was only methane and its Faradaic efficiency was < 2%. In contrast, the Faradaic efficiency of hydrogen was very large (∼ 100%). The effect of potential on current efficiencies for the products by electrochemical reduction of CO2 with Cu electrode in methanol at 273 K showed that the main products from CO2 were CH4, ethylene, CO, and formic acid. High formation efficiency of methane was observed at low temperature only in the methanol-based electrolyte.