(324e) Microwave Fluidized Bed and Microwave Hybrid Fixed Bed Reactor for the Ethane Dehydroaromatization Reaction

Ethane dehydroaromatization under microwave heating has been demonstrated as an efficient process for the conversion of ethane to ethylene over a metal loaded zeolites. However, microwave heating has displayed a deficit in the capability to efficiently aromatize the abundant amount of ethylene produced into the target products benzene and toluene. The low aromatic selectivity is attributed to the underutilization of the catalyst bed due to hot spot formation that drives the high conversion at low temperatures. The objective of this research was to take a systems approach by changing the microwave reactor configurations so that catalyst bed utilization can be increased. In this research a 6%Mo/ZSM-5 catalyst was tested in thermal, microwave, and microwave hybrid heated fixed bed setups. Thermal or microwave heated non-optimized fluidized bed configurations for the ethane dehydroaromatization reactions were also tested. The effects of each reactor configuration were concluded by comparing similar ethane conversions by varying the temperature and power needed in each reactor setup while holding all other variables conditions constant. The temperature distributions on the different microwave heating was examined by a thermal imager and the reaction products were tracked by a micro-GC. It was determined that the addition of the thermal heating to the microwave fixed bed was able to increase aromatic selectivity in comparison to only microwave heating. The fluidization of the catalyst bed resulted in a three times higher aromatic selectivity than when compared to the microwave fixed bed. The microwave fluidization prevented localized hot spot formation thus preventing the detrimental degradation of the zeolite structure. However, the microwave fluidized bed required three times the amount of power to heat the catalyst in comparison to the microwave fixed bed.