Regularities of Oxidative Dehydrogenation of Ethane Over MoVNbTeOx Catalyst Under Supercritical Conditions

Abstract

One of the most active and high-selective catalytic systems for oxidative dehydrogenation of ethane is the MoVNbTeOx catalyst. However, this catalytic system has the low thermal stability and is prone to deactivation at temperatures above 350 °C. At the first time it was proposed to use oxygen ((Tcr = –119 °C, Pcr = 48 atm) and ethane (Tcr = 32 °C, Pcr = 51 atm) in supercritical state in the oxidative dehydrogenation process. Carrying out the process at supercritical conditions (T = 240–300 °C, P = 60–100 atm) leads to high selectivity up to 90% for ethylene under growth conversion of ethane and oxygen. At the same time, it manages to keep M1 phase crystallinity unchanged throughout the experiment (more than 40 h). Dependences of ethylene productivity on pressure (Reaction conditions: T = 280 °C, C2H6:O2:N2 = 31:23:46, 2 g of catalyst, the density of the reagent mixture varies from 0.65 (at 1 atm ) to 63.15 kg/m3 (at 100 atm )