The oxidative dehydrogenation of n-butane in a differential side-stream catalytic membrane reactor

Abstract

The synthesis of butenes and butadiene from the oxidative dehydrogenation of n-butane is a chemical reaction of economic relevance and the choice of catalyst is of considerable importance. In this simulation exercise a V/MgO catalyst in a differential side-stream catalytic membrane reactor was studied. The Recursive Convex Control (RCC) algorithm was used to determine the operating parameters required to determine the maximum yields of hydrocarbon products. The algorithm, in addition to selecting for the duty a single differential side-stream catalytic membrane reactor (DSR) in preference to a CSTR and a PFR, also developed the profile for the optimal addition of oxygen along the length of the reactor. The maximum yield of butenes, all three isomers, was found to be 0.119 carbon mass fraction. The maximum yield of butadiene from the ODH of n-butane was found to be 0.799 carbon mass fraction. The rates of formation of hydrocarbon reactants and products are discussed. Statistical analyses of the ratios of formation rates of the butene isomers and of carbon dioxide to carbon monoxide are presented. The interplay between alternative reaction routes for the formation of butadiene is reviewed as well as the validity of the kinetic data at low oxygen partial pressures.