In situ infrared study of formate reactivity on water–gas shift and methanol synthesis catalysts

In order to investigate the methanol synthesis reaction from CO2/H2, a comparative study of the reactivity of formate species on different types of catalysts and catalyst supports has been carried out. Formic acid was adsorbed on water–gas shift catalysts, Cu/ZnO/Al2O3 methanol synthesis catalyst and ZnO/Al2O3 support, Cu/ZnO/ZrO2 and Cu/ZnO/CeO2 methanol synthesis catalysts as well as their corresponding supports ZnO/ZrO2 and ZnO/CeO2. Superior reactivity and selectivity of dedicated methanol synthesis catalysts was evidenced by their behavior during the subsequent heating ramp, when these samples showed the simultaneous presence of formates and methoxy species and a higher stability of these reaction intermediates in the usual temperature range for the methanol synthesis reaction.