(Ni/MgAl 2 O 4 )@SiO 2 core–shell catalyst with high coke-resistance for the dry reforming of methane

A novel core–shell catalyst as [(Ni/MgAl2O4)@SiO2] was successfully prepared by three steps. First, the support was prepared, then 10 wt% Ni was loaded upon the support by the wetness incepting impregnation method; finally, the catalyst was coated with mesoporous silica. Two supports with different sizes were synthesized by homogeneous precipitation method and solution combustion method, respectively. Based on different supports, two series of catalysts with the characteristics of same components and different particle diameters were obtained. All catalysts were characterized by X-ray diffraction, transmission electron microscopy, N2-physisorption and thermal gravimetric analyzer to measure the crystallinity, morphology, surface structure and carbon deposition. The results shown that core–shell catalysts [(Ni/MgAl2O4)@SiO2] had better coke-resistance and stability than the uncoated catalysts (Ni/MgAl2O4). Therefore, core–shell catalyst coated by silica exhibited better performance in dry reforming of methane.