Hydrogenolysis of methyl formate over copper on silica: I. Study of surface species by in situ infrared spectroscopy

摘要: The hydrogenolysis of methyl formate to methanol over silica-supported copper has been studied using in situ infrared spectroscopy coupled with simultaneous determination rate. Under flow reaction conditions two forms adsorbed exist. One a carbonyl absorption at 1726 cm−1 and is bound the support by hydrogen bonding heat adsorption 65 kJ mol−1. second absorbs 1666 an approximate 140 At 457 K rate directly proportional band intensity latter hence it, or another species equilibrium involved rate-determining step. Adsorption CO from COH2 mixtures gives rise single 2117 cm−1, corresponding being 60 Competitive measurements under show that will partially displace not vice versa. Nonetheless does reversibly inhibit this attributed its displacing surface. lower concentration surface also reduces hydrogenation formaldehyde intermediate leading deposition as polymer revealed bands 1483 1375 cm−1. same accretes more rapidly during reverse for which substantial by-product pressures are much than used hydrogenolysis. Continuous deactivation catalyst then observed.