Ethane dehydrogenation in a membrane reactor with palladium alloy foil Pd-Ru with alumina-chromium catalyst at high temperatures

Ethane dehydrogenation is one of the most important processes for ethylene production. The main regularities of this process have been studied in a membrane reactor with an industrial alumina-chromium catalyst and a Pd-6%Ru palladium alloy foil. The working part of the reactor consists of two cylindrical chambers separated by a membrane partition. The upper chamber is vacuumed and the lower chamber is kept at atmospheric pressure. It is known that hydrogen additives at the inlet prevent the formation of carbon deposits on the catalyst, so in this work the effect of these additives on the process was investigated. With uniform feedstock supply (ethane and hydrogen) along the outer perimeter of the lower chamber, the problem is reduced to finding the fluxes of ethane, ethylene, hydrogen and methane from the solution of a system of nonlinear ordinary differential equations. The temperature interval 600 K < T < 1000 K at small values of hydrogen and ethane flux ratios at the inlet is considered. The conditions under which hydrogen yield and ethane conversion reach 100% at maximum flux H2 through the membrane are found. Calculations are compared with experimental data.