Simultaneous production of methanol, DME and hydrogen in a thermally double coupled reactor with different endothermic reactions: Application of cyclohexane, methylcyclohexane and decalin dehydrogenation reactions

Abstract

Three different units of a multi-tubular reactor with 2962 three concentric tubes have been investigated as a thermally double coupled reactor (TDCR) in co-current mode. Exothermic reactions are same for all three units and are occurred in the inner (methanol synthesis) and outer tubes (direct DME synthesis from syngas) while endothermic reaction is different for each unit. Three endothermic dehydrogenation reactions of cyclohexane (CH), methylcyclohexane (MCH) and decalin (DC) have been considered for middle tube side of each unit. A steady-state heterogeneous catalytic reaction model is applied to evaluate the performance of TDCR for simultaneous production of methanol, hydrogen and dimethylether (DME) in one reactor. The simulation results of each unit are compared with others that operated at the same feed conditions. Results show that conversion of CH, MCH and DC reaches to 67%, 56% and 77% at the output of each unit respectively. Output methanol yield with application of CH and MCH dehydrogenation as endothermic reactions are same equal to 0.37. Also, methanol yield for DC unit is 0.33. In addition, conversion of monoxide at the output of DME synthesis side reaches to 64%, 65% and 62% for CH, MCH and DC units, respectively.