Hydrogen production from methanol over combustion-synthesized noble metal/ceria catalysts

Methanol decomposition (MD), steam reforming of methanol (SRM) and combined steam reforming of methanol (CSRM) were carried out over three noble metal (Pt, Pd, Rh)/ceria catalysts prepared via the combustion method. XPS measurements suggested the presence of highly dispersed (mainly) oxidized noble metal species in the as-prepared (oxidized) samples, while in-situ reduction led to metallic states only in the cases of palladium and platinum. Their activity increased in the order Rh < Pt < Pd for all three processes, while their selectivity towards CO production was remarkably high, even in the presence of steam, a fact that implies higher activity for methanol decomposition and lower activity for hydrolysis of methyl formate. Based on the activity/selectivity results an overall reaction scheme, which includes the production of both main products and by-products, is proposed.