MODELING OF MEMBRANE REACTOR FOR METHANOL SYNTHESIS

Abstract

Hydrogenation of carbondioxide into methanol is today considered as one of the promising methods to mitigate the greenhouse effect, caused by a substantial rise in CO2 concentration in the atmosphere. Furthermore the methanol produced could be used as a fuel or basic material for producing various organic chemicals. From a thermodynamic point of view the yield of methanol synthesis is limited by the equilibrium. In order to increase the methanol yield, it is necessary to in situ removal of the condensable products (CH3OH and H2O) of the reaction. A membrane reactor satisfies this situation by selectively removing some reaction products from the reaction system. In the present dissertation work, a steady state model for isothermal conditions has been developed which incorporates 10 differential equations along with 10 boundary conditions for state variables and appropriate constitutive relationships. The model equations are solved by using MATLAB ODE (Ordinary Differential Equations) solvers. Zeolite membranes with different values of the CH3OH and H2O permeances are considered in the membrane reactor modeling. The purpose of this study is to investigate the possibility to increase the CO2 conversion into methanol in a membrane reactor with respect to traditional reactor. A comparison study is performed with the two types of zeolite membranes with respect to traditional reactor. for CO2 conversion, methanol selectivity and methanol yield. In the view of above simulation results it is concluded that the membrane reactor is showing better performance with respect to traditional reactor at any temperature