Perfomances of different additives on NiO/γ-Al2O3 catalyst in CO methanation

Abstract

In this work, NiO/c-Al 2 O 3 catalyst with different additives prepared by excessive dipping method, was investigated in CO methanation in an attempt to improve the reaction activity and enhance the anti-coking property. The influences of additives, such as Zr, Co, Ce, Zn and La, on catalysts in performance of CO methanation were studied in a fixed-bed reactor. The catalysts were charac-terized by XRD, H 2 -TPR, H 2 -TPD and CO-TPD. The results showed that the addition of the additives could promote the dispersion of nickle species on support and decrease the crystallite size of Nickel species. The reduc-tion temperatures of catalysts were all reduced except the one with Mg. The catalytic results showed that additives improved the reaction activity of CO methanation. Espe-cially, the addition of La gave the best catalytic perfor-mance of 100 % CO conversion and 99.61 % CH 4 selectivity, respectively. The space–time yield of CH 4 was achieved as high as 2134.5 g kg -1 h -1 .