Using Quartz Crystal Microbalance/Heat Conduction Calorimetry To Monitor Heterogeneously Catalyzed Reaction Rates And Change Of Surface Mass: Hydrogenation Of C2H4 On Palladium And Platinum

摘要

The quartz crystal microbalance/heat conduction calorimeter (QCM/HCC) has been used to monitor simultaneously the heat of reaction and the change in surface mass when hydrogen and ethylene in a carrier gas of nitrogen combine catalytically on both a palladium and a platinum surface at temperatures of 25 – 50°C. The QCM/HCC can easily detect the heat evolved and the mass increase due to sorption of H2 in thin Pd films at 25°C and 1 atm. The catalytic heat generated when both gases are present is accompanied by a small decrease in the mass of the platinum film and its adsorbed hydrocarbon layer. The measured turnover frequency of the H2 + C2H4 reaction on Pt is consistent with literature values