Effect of support on the performance of Ni-based catalyst in methane dry reforming

Abstract

Ni-based catalysts with different supports were prepared and characterized by N2 physisorption, XRD, H2-TPR, H2 chemisorption, and so on; the effect of support on the performance of Ni-based catalyst in methane dry reforming was then investigated. The results indicated that the support has a significant influence on the state of NiO species. SiO2, TiO2 and ZrO2 as a support have a weak interaction with NiO, which facilitates the reduction of the corresponding catalysts; however, the weak interaction may also lead to quick deactivation due to the agglomeration of active metal species. Al2O3 and MgO have a strong interaction with NiO, which may promote the formation of NiAl2O4 spinel and NiO-MgO solid solution, respectively, and make the reduction of corresponding catalysts very difficult. Al2O3 modified by MgO is provided with both proper textural properties and interaction strength between metal and support, which are in favor of the dispersion and stabilization of NiO species. As a result, NiO supported on MgO-modified Al2O3 exhibits superior catalytic performance in methane dry reforming even under very high gas hourly space velocity; it is quite stable during a long term test of more than 100 h.