Abstrait

Investigation of the optimum conditions for the electrocatalytic oxidation of methanol on Ti/PbO2modified electrode

S.S.Mahmoud*, M.M.Ahmed

Electrocatalytic oxidation of methanol on Ti/PbO2 electrode (as anode) was investigated in different conductive electrolytes. The highest electrocatalytic activity was achieved in the presence of NaCl (2g/l) and could be attributed to indirect oixdation ofmethanol by the electrogenerated hypochlorite ions from the oxidation of chloride ions. In addition, contribution fromdirect oxidation 0could also is possible via reaction oofmethanol with the electrogennerated hydroxyl radicals adsorbed on the Ti/PbO2 modified electrode suurface. In the presence of NaOH, the electrocatlytic activity of the employed anode was not compared to that in NaCl due primarily to the absence of chloride. This indicates that methanol degradation in NaOH occurs exclusively via direct electrochemical process. However in H2SO4, the electrode performance was poor due partially to the absence of chloride from the conductive solution. The possiibility of electrode poisoning as a result of growth of adherent film on the anode surface. Optimizing the conditions that ensure effective electrochemical degradation of methanol on Ti/PbO2modified electrode necessitates the control of all the operating conditions.