IN-SITU FT-IR SPECTROSCOPY AND KINETIC-STUDY OF METHANOL SYNTHESIS FROM CO H-2 OVER ZNAL2O4 AND CU-ZNAL2O4 CATALYSTS/

The CO/H-2 reaction over ZnAl2O4 (support) and Cu-ZnAl2O4 (catalyst) p erformed at 250 degrees C up to 0.3 MPa, was studied by combining in-s itu FT-IR experiments and kinetic investigations. The obtained results showed the existence of two reaction mechanisms for methanol formatio n involving formate species (mainly on ZnAl2O4) and carbonyl species ( on Cu-ZnAl2O4), as key reaction intermediates. Inactive formate specie s were also evidenced. Carbon dioxide, which is the initial major prod uct formed on the ZnAl2O4 support, is produced through the partial red uction of the latter.