About the Mechanism of Methanol Synthesis
4th International Natural Gas Conversion Symposium
19-23 Nov 1995
||Natural Gas Conversion IV : Proceedings of the 4th International Symposium, 19-22 November 1995, Kruger National Park, South Africa
582 c. ISBN 9780444823526.
Studies in Surface Science and Catalysis
||OXIDE CATALYSTS; COPPER CHROMITE; STATE; HYDROGEN; ACETONE
Boreskov Institute of Catalysis, Pr.Ak.Lavrentieva,5, Novosibirsk 630090,
This chapter presents an overview of the mechanism of methanol synthesis. The synthesis of methanol is catalyzed by copper-containing catalysts. The reduction of an anion-modified ZnO-based solid solution in a H2 medium results in the allocation of ca.50% Cu as metal particles over the ZnO surface and the dissolution of a corresponding quantity of hydrogen in the bulk of ZnO. The reaction between oxygen and copper atoms results in the adsorption of CO2 in the reaction medium. The hydrogenation of CO2 proceeds in two stages—(a) formation of methanol and (b) formation of water. The formation of methanol proceeds via hydrogenation of one of the C–O bonds. This leads to the formation of methanol and an oxygen-containing site. The oxygen-containing sites may proceed toward two different directions. Firstly, it may react with hydrogen to produce water and copper atoms (the catalyst regains its reduced state). Secondly, it may react with CO to produce a fragment whose structure resembles that of the fragment formed upon adsorption of CO2 on metal atoms; as a result a CO molecule is rapidly hydrogenated to methanol. The ratio of the rates of reactions determines the ratio of the rates of methanol formation from CO2 and CO, respectively.