Simulation of selective reactions’ performance in transient regimes with periodical separate feeding of reagents: Case study: Propane oxidative dehydrogenation in adiabatic V–Ti catalyst bed

The model simulation study has shown that the anaerobic process of oxidative dehydrogenation of propane under periodic alteration of feeding between propane and air may be realized in adiabatic catalyst beds in stable continuous cyclic mode in two-reactor scheme. In case of appropriate choice of process parameters (cycle duration and residence times), the process appears to be autothermal, i.e. it does not require any inlet gas preheating for stable operation. Compared to similar steady-state adiabatic process, the proposed process is characterized with much lower maximum catalyst temperatures, giving the way to process pure propane without diluting it with inert gases, thus simplifying downstream procedure of product separation. Predicted propylene yield is competitive with one for the steady-state adiabatic process, while sufficient technological benefits of the new technology are expected (decrease of energy consumption and minimization of heat-exchange environment, simplification of product separation procedure, process safety improvement, suppression of coke formation and efficient coke incineration). Notably, the proposed process is characterized with much more degrees of freedom available for further development and optimization than conventional steady-state technologies.