Electrochemical promotion of catalytic reactions with Pt/C (or Pt/Ru/C)//PBI catalysts.

The paper is an overview of the results of the investigation on electrochemical promotion of three catalytic reactions: methane oxidation with oxygen, NO reduction with hydrogen at 135 °C and Fischer–Tropsch synthesis (FTS) at 170 °C in the [CH₄/O₂(or NO/H₂ or CO/H₂)/Ar//Pt (or Pt/Ru)//PBI(H₃PO₄)/H₂, Ar] fuel cell. It has been shown that the partial methane oxidation to C₂H₂ and the C₂ selectivity were electrochemically promoted by the negative catalyst polarization. This was also the case in NO reduction with hydrogen for low NO and H₂ partial pressures. In both cases the catalytic reactions have been promoted by the electrochemically produced hydrogen. It has been found that the NO reduction with hydrogen on the Pt/PBI strongly depends on NO and hydrogen partial pressures in the working gas mixture. At higher NO and H₂ partial pressures the catalysis is promoted by the electrochemical pumping of H⁺ from the catalyst, i.e. at positive polarization. FTS demonstrated the highest methane production rate (11% of CO conversion) at zero fuel cell voltage. [ABSTRACT FROM AUTHOR]