Improvement in efficiency of a chemical reaction system for converting methanol to light olefins by periodic operation

Behavior of a chemical reaction system for converting methanol to light ole fins in a fixed bed reactor under a periodic operation was investigated via numerical simulation to improve the efficiency, of the system through the enhancement of yields of the desired products such as ethylene and propylen e. In the periodic operation, the reactor wall temperature was set to vary sinusoidally along its axis. The recycling of by-products such as pentene a nd butylene was also studied. As a result, we found that the combination of the wall temperature modulation and the rec-cling of pentene led to the po ssible increases in the ethylene and propylene yields Of LIP to ca. 33% and ca. 16%, respectively,, compared with those obtained with a uniform wall t emperature. Further, it was shown that the product ratio of propylene to et hylene can be changed in the range of 1.60 to 6.05 when butylene is recycle d, This suggests that production with variable composition of ethylene and propylene according to need is possible by changing the wall temperature mo dulation arid the recycling ratio even in the same reactor.