Comparative Study on the Kinetic Modeling of the Oxidative Coupling of Methane in Laboratory and Bench Scales

Abstract

The aim of this work is to develop and compare kinetic models for the oxidative coupling of methane (OCM) based on the gas hourly space velocity (GHSV) value and CH4/O2 ratio in two scales: laboratory and bench. The experiments were carried out in tubular fixed bed reactors at 1023 K, using 0.7-1.5 g and 30 g of perovskite titanate as the reaction catalyst for laboratory and bench scales, respectively. The various GHSVs (8000, 12000, 17000 h-1) and (3400, 4300, 5200 h-1) and methane to oxygen ratios (1, 2, 3, 4, 7.5) and (2, 2.5, 3) were selected for laboratory and bench scales, respectively. We have proposed a mechanism in which the consumption rate of methane is always twice of production rate of C2. A power law model was assumed for rate of reaction in terms of partial pressure of oxygen and methane. Using a linear regression analysis, the kinetic models were determined. Comparison of the calculated rate of reaction with the experimentally measured data confirmed the accuracy and applicability of the developed model for both scales.