Effects of Various Metal Cations on the Ethanol Oxidation in Aqueous Acidic Solution

The effects of CdSO4, Cd(NO3)2, (CH3COO)2Cd, ZnSO4, Zn(NO3)2, (CH3COO)2Zn, K2SO4, KNO3 and CH3COOK on the anodic oxidation of ethanol were studied at a platinum el ectrode in aqueous acidic solution by means of linear sweep voltammetry. The anodic current due to ethanol oxidation increased by the addition of cadmium or zinc salts. The active species responsible for ethanol oxidation was suggested to be univalent Cd+ and Zn+, which may oxidize the reaction intermediates of ethanol. The order of the catalytic activity is as follows: CdSO, >Cd (NO3) 2>(CH3COO) 2Cd ZnSO4 (NO3) 2. Potassium salts and (CH3COO)2Zn are either ineffective or inhibitory.