Membrane reactor system model for gas conversion to benzene

Abstract

In the direct nonoxidative conversion of methane gas to liquid chemicals, it has been shown that continuous removal of produced hydrogen is a way to overcome the thermodynamic limit of low equilibrium methane conversion. A plug-flow, isothermal membrane reactor model was developed for the conversion of methane gas to aromatics over Mo/H-ZSM5 and integrated in an Aspen Plus process model using COCO (CAPE-OPEN to CAPE-OPEN) Simulator. Parameters such as reaction rate constants and equilibrium coefficients required by the model were obtained using experimental data. The reactor employs a simplified reaction network whose product distributions agree well with other models and published results. Damkohler number of 0.5 and a dimensionless hydrogen removal parameter δ of 10 were found to be the optimum parameters for benzene selectivity. The reactor model being embedded in the process allows for more detailed exploration of the impact of reactor parameters on the process as a whole. Methane conversion remains at 10.9% and 20% for each case with or without recycle. Benzene molar flow increases by 72% for the single pass configuration when Da=0.5 and δ=10 are used; however, naphthalene molar flow increases by 215%.