Reduction of CO2 under high pressure and high temperature on Pb-granule electrodes in a fixed-bed reactor in aqueous medium

The electrochemical reduction Of CO2 has been investigated on Pb granule electrodes at high-pressure conditions and high temperatures (electrode potentials between -1.6 and -2.1 V) by using aqueous 0.2 M K2CO3 as electrolyte in a fixed-bed reactor. Only formic acid was found as a reaction product. The maximum Faradaic efficiency of the product was found to be 94% at -1.8 V (SCE). The space-time yield of the reaction was found to be 1.3 x 10(-3) kg L-1 h(-1) with an A(v) value of 1.1 cm(-1). Transfer coefficient, beta, of the reaction was 0.11, and the exchange current density, j(o), was found to be 4.1 x 10(-4) A cm(-2). (C) 2004 Elsevier B.V. All rights reserved.