Cyclic Regeneration of Cu/ZnO/Al2O3 Nano Crystalline Catalyst of Methanol Steam Reforming for Hydrogen Production in a Micro-Fixed-Bed Reactor

Document Type : Research Article

Authors

1 Catalysis and Nanostructured Materials Research Laboratory, School of Chemical Engineering, College of Engineering, University of Tehran, P.O. Box: 11155/456, Tehran, I.R. IRAN

2 Gas Research Division, Research Institute of Petroleum Industry (RIPI), P. O. Box 14665-137 Tehran, I.R. IRAN

Abstract

Hydrogen can be produced for fuel cell applications by using methanol steam reforming reaction. In this article, a method was developed for regeneration of accelerated deactivated methanol-steam-reforming catalyst. Successive deactivation–regeneration cycles were studied in a 250 hours test for the first time including 6 regeneration cycles. It is shown that regeneration of the catalyst in diluted O2 results in dramatic enhancements of the methanol conversion and this catalyst could be regenerated to near fresh activity. Cokes that can deactivate the catalyst will be burned out in presence of oxygen at the regeneration step. XRD, TGA/DTG, TPR, N2O Chemisorption, TPO and SEM techniques were used for a complete catalyst characterization. Effects of temperature, water to methanol ratio, concentration of diluted oxygen, CuO/ZnO ratio and adding oxygen along with or without the main feed were also studied by a set of six experiments with duration of 100 h for each to provide a complete know-how on the developed method of regeneration.

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