(104b) Microwave-Assisted, Performance-Advantaged Direct Propane Dehydrogenation

Non-oxidative propane dehydrogenation (PDH) produces on-site propylene, a valuable chemical feedstock. Although widely used, its efficiency is limited due to moderate selectivity and significant catalyst deactivation, which makes it operate at lower-than-ideal temperatures. This results in high energy consumption and significant pollution in the chemical industry. We demonstrate that employing microwave (MW) heating with PtSn/SiO₂ catalyst pellets in a SiC monolith, acting as a MW susceptor and heat distributor, can enhance the process while maintaining conditions comparable to traditional reactors. Continuous tests show that the MW reactor remains active and stable at 500°C without the co-feeding hydrogen. At higher temperatures, feed concentrations, and with increased space velocity, MW-heated catalysts exhibit remarkable coke resistance, high activity, and exceptional selectivity, unlike conventionally heated reactors that suffer from severe deactivation. Gas-solid temperature gradients are investigated computationally, and nanoscale temperature discrepancies help elucidate the distinct coke formation mechanisms between the heating methods. This strategy highlights the immense potential of electrifying catalytic reactions for eco-friendly chemical production.