Hybrid plasma-catalytic methanation of CO2 at low temperature over ceria zirconia supported Ni catalysts

摘要

A hybrid plasma-catalytic system was used in for the hydrogenation of carbon dioxide (CO2) into methane (methanation) at atmospheric pressure and very low temperature using a dielectric barrier discharge (DBD) plasma reactor packed with Ni-Ce(x)Z(1-x)O(2) catalysts. Three catalysts were prepared by a conventional wet impregnation method, using 15 wt% of Ni loading over ceria-zirconia mixed oxides having different Ce/Zr ratios. The physico chemical features of both catalysts and supports were evaluated by means of X-Ray Diffraction (XRD), Temperature-Programmed Reduction of H-2 (H-2-TPR), Temperature Programmed-Desorption of CO2 (CO2-TPD) and Transmission Electron Microscopy (TEM). The methanation experiments in the absence or in the presence of plasma were carried out in the temperature range of 90-420 degrees C. The hybrid plasma 15NiCZ5842 catalyst combination was found to efficiently convert CO2 into methane even at low temperature. Indeed, CO2 conversions as high as 80%, together with 100% selectivity toward methane was measured in the presence of plasma at 90 degrees C. On the contrary in the absence of plasma, the same conversion and selectivity were only achieved at much higher temperatures around 300 degrees C, for the same catalyst. (C) 2016 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.