Non-oxidative Dehydrogenation of Methanol to Formaldehyde over Bulk β-Ga2O3

The non-oxidative dehydrogenation of methanol to formaldehyde is considered a dream reaction compared with the classical oxidative route, because the valuable coupled product hydrogen is formed instead of water, and the produced anhydrous formaldehyde is highly suitable for the further synthesis of oxygenated synthetic fuels. This study reports on the high catalytic performance of pure beta-Ga2O3 in this reaction at temperatures between 500 degrees C and 650 degrees C. At 550 degrees C and a GHSV of 45500 h(-1), an initial selectivity to formaldehyde of 77 % was obtained at a methanol conversion of 72 %. Performing the reaction at temperatures beyond this range and lower GHSV resulted in a lower formaldehyde selectivity. The catalyst suffered from deactivation caused by formation of carbon deposits, but it was possible to regenerate its initial activity at 500 degrees C and 550 degrees C completely by an oxidative treatment. Irreversible deactivation occurred at 650 degrees C due to partial volatilization of Ga2O3.

Automated summary

This study reports on the high catalytic performance of pure beta-Ga2O3 in the non-oxidative dehydrogenation of methanol to formaldehyde reaction. Higher formaldehyde selectivity can be achieved under appropriate temperature and GHSV conditions. The catalyst is affected by carbon deposits and Ga2O3 volatilization.