Intensification of the dehydrogenation process of different hydrocarbons in a catalytic membrane reactor

摘要

The process of dehydrogenation of hydrocarbons has attracted a great interest due to the growing demand for monomers for main organic synthesis. Among them, ethylene, propylene, and styrene occupy the leading positions. The efficiency of the dehydrogenation process was numerously shown to be significantly improved by the use of catalytic membrane reactors. Hydrogen elimination from the reaction zone shifts the equilibrium towards products, thus increasing their yields. At the same time, the amount of parallel by-side reactions and, consequently, by-side products can be varied substantially. In the present work, the processes of ethane, propane and ethylbenzene dehydrogenation in catalytic membrane reactors are theoretically compared in terms of efficiency and productivity. A two-dimensional non-isothermal stationary mathematical model of the catalytic membrane reactor was applied to perform the study. The reactor comprises inner hydrogen-permeable tubes with a loaded dehydrogenation catalyst and outer tube. The shell compartment is filled with another catalyst for oxidation of flux hydrogen. It is evident that the heavier is a hydrocarbon, the higher amount of by-products is formed. Since the contribution of the coke formation process is being increased along with temperature, diminishing of the reactor temperature by oxidation of flux hydrogen allows enhancing the target products' yield.