OPTIMIZATION OF OXIDATIVE COUPLING OF METHANE OVER PEROVSKITE CATALYST AND OCM KINETICS MODELING BY GENETIC ALGORITH

In recent years, there is a strong incentive to study and develop processes that would convert methane into more valuable chemical & petrochemical products.
To this end, in this research, kinetic studies on the oxidative coupling of methane at temperatures of 725, 750, 775, 785°C and a methane/oxygen ratio of 2, 3, 3.5, 4 and 4.5, have been conducted in a tubular fixed bed reaction, using perovskite titanate as the reaction catalysts; optimum operating conditions have been proposed. Correlation of the kinetic data has been performed with the models proposed and their parameters have been optimized.
Modeling is based on random searching algorithms, of which GA is one. Six models have been selected among the common kinetic models; then, the selected models have been regressed with experimental data obtained from the ‍‍Catatest system by GA, in order to obtain optimized parameters.
One of the selected models (Santamaria) had good agreement with experimental data. The Arrhenius parameters of this model have been obtained by linear regression. The Marquardt algorithm has also been used in this research and its results compared with GA. It should be noted that the Marquardt algorithm is sensitive to first guesses and there is a possibility of trapping in the relative minimum.