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This paper presents an investigation of the effect of reaction pressure to the activity and stability on Cu/Cr/Mn catalysts for the methanol dissociation reaction under pressure. In order to understand the catalyst deactivation, the catalysts were undergo a series of long time on-stream test and their physical properties beford and after the test were also examined by BET, N2O/H2 titration, XRD ,SEM and EA.
Kinetic studies examined the influence of reaction pressure on the rate-controlling mechanism of the methanol dissociation reaction. We also compared various business caralysts (G-66， G-99， T-2107et al.)with the activity of the Cu/Cr/Mn catalysts with and without modification of alkali metals, and observed the influence of adding CO2 in the feed.
Experiment results show that higher reaction pressure will decrease the activity but clearly increase the stability of catalysts such as the result of adding 20%CO2 in the feed. Adding 2wt% K shows the best promoting affect due to K can enhance the dispersion of active copper. But the Cu/Zn catalysts were not adequate for the methanol dissociation reaction.
It is found by BET ; XRD,EA analysis that the catalyst dectivation may be attributed to singerign and coking at higher reaction temperature. High reaction pressure decreased the coking is the reasion why it can enhance the stability of catalysts.Carbon deposit found in the reaction is retarded by high reaction pressure which increase the CO2 content in reaction system.
Finally, we obtained the following rate equations and parameters with power law model: －rp =1.09x10 8xe22.19/RT xP1.25CH3OHPH2-1.32 PCO-0.31
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