Methanol conversion to olefins over high-silica zeolites in continuous flow fixed-bed reactor

Methanol is a basic petrochemical product produced world-wide in relatively large quantities. Its conversion to hydrocarbons has received great interest. Methanol conversion over high silica-zeolites in a continuous flow fixed-bed reactor was studied in our laboratory. The reaction conditions were optimized for the production of light olefins. Commercially available zeolites were modified, and new ones were synthesized locally. Catalytic performances of commercially available zeolites and of the synthesized one were evaluated. The obtained results indicate that the selectivity of commercial zeolites was improved. However, zeolite active life-time was decreased. The locally synthesized high-silica zeolite has shown better performance than the commercially available ones. Analysis of used (deactivated) samples proved that carbon deposition is the main factor affecting catalyst activity and selectivity. Therefore, fixed-bed operation is not suitable for methanol conversion over zeolite catalysts.