Temperature-programmed desorption studies of methanol and formic acid decomposition on copper oxide surfaces

We have obtained temperature-programmed desorption data for methanol and formic acid adsorption on bulk powders of CuO and Cu2O. Methanol adsorption on CuO at 300 K results in CO2, H-2 and H2O desorption at 550 K indicating formate decomposition; this decomposition temperature is very close to that obtained from the decomposition bf formate produced by formic acid adsorption. No significant desorption was observed from vacuum-annealed Cu2O following exposure to methanol due to the formation of a copper metal film at the surface. However, formic acid was adsorbed on this surface decomposing at significantly lower temperature, 485 K, than on CuO.