Design of highly selective heterogeneous catalyst for CO2-mediated ethane oxidative dehydrogenation based on nonoxidative catalysis in stainless-steel reactor

• Ethane dehydrogenation in empty steel reactor yielded 90% ethylene selectivity. • Active phases formed on the inner wall of the stainless steel reactor. • Highly selective catalyst has been developed for oxidative ethane dehydrogenation. • Catalyst phase FeCr 2 O 4 is responsible for high ethylene selectivity. Highly selective and active phases in the ethane dehydrogenation were formed on the inner wall of stainless-steel reactor after its long-term using in the process at 650–750 °C. The conversion of ethane at 650 °C reached up to 40% with ethylene selectivity closed to 90%. Fe-Cr-Ni and Fe-Cr oxides catalysts supported on carbon were created for CO 2 –mediated oxidative dehydrogenation of ethane (ODE) based on SR-XRD analysis of the inner wall of the steel reactor. In the case of Fe-Cr-Ni/C catalyst, the ethylene selectivity decreased and the catalyst was rapidly deactivated by coke deposits. On Fe-Cr/C catalyst, the ethylene selectivity was 82% and ethane conversion was above 20% at 700 °C. It was found that phase FeCr 2 O 4 forms on the surface of Fe-Cr/C catalyst, which, as we assume, is responsible for high stability of the catalyst and its high selectivity of ODE with CO 2 .