METHANATION ON SUPPORTED NICKEL CATALYSTS USING TEMPERATURE PROGRAMMED HEATING

The techniques of temperature programmed desorption and temperature programmed reaction were used to study methanation of carbon monoxide on three high-weight loading, supported nickel catalysts. A flow system at atmospheric pressure and a mass spectrometer detector was used to continuously monitor the products leaving the surface. The desorption spectra of adsorbed CO and of CO2 were dependent on the catalyst properties. On all three catalysts CO and CO2 desorbed from the surface during heating following CO adsorption. Products were observed leaving the surface up to temperatures in excess of 500 °C. The reaction of coadsorbed CO and H2 as well as the reaction of adsorbed CO with flowing H2 were studied on each of the catalysts. Both CH4 and H2O were observed leaving the catalyst surface at the same temperature indicating that CO bond breaking was rate determining. The results show that temperature programmed desorption is a very useful technique for studying reaction mechanisms as well as characterizing catalysts. © 1979.