Kinetic modeling of the anaerobic oxidative dehydrogenation of n-butane

Abstract

This paper describes the kinetic modeling for the anaerobic oxidative dehydrogenation of n-butane over a V/MgO catalyst supported on α-Al₂O₃. Based on the experimental data reported by Fandiño and Guaran (2007), a mathematical model for the experimental reactor was proposed together with a model that describes the depletion of the catalyst's mobile oxygen throughout the process. Different kinetic models were developed; two of them (M3 and M4) were based on proposed reaction networks with reaction mechanisms for each one of the involved reactions. Other two models (M5 and M6) were based on a semi-empirical approximation for the expression of the reaction rates. A non-linear regression algorithm was developed and used to obtain the kinetic parameters for each model. Afterwards, several statistical tests (mean-squared error test, chi-squared test and t-test) and a cross-validation test were conducted to evaluate and discriminate between models. The kinetic parameters and their corresponding confidence intervals were determined for each model. All named models exhibited a satisfactory fit to the experimental data. The results show that models M3 and M5 can be discarded, while models M4 and M6 can be retained and used to predict the behavior of the ODH of n-butane at the studied conditions.