Sensitivity of the properties and performance of Co catalyst to the nature of support for CO2 reforming of CH4

Abstract

The structural phases, spinel inversion degree, metal reduction, and performance of Al-Ox and Mg-Al-Ox supported monometallic Co and Ni catalysts, prepared by co-precipitation method, were studied for dry reforming reaction. Catalysts were characterized using ICP-MS, N2-physisorption, XRD, 27Al NMR, CO2-TPD, Ni/Co K-edge XANES and TPO. Incorporation of MgO increased the pore size, while BET surface area was decreased. XRD showed a single spinel phase of NiAl2O4 and CoAl2O4, and the introduction of MgO created an additional phase (MgO-solid) and increased the degree of spinel inversion in both supported Ni and Co monometallic catalysts. These changes promoted better metal dispersion, increased basicity and easy reduction of the active metal. Increased performance was also noticed in the Mg-Al-Ox supported catalysts, with higher resistance to carbon deposition due to the above-mentioned properties related to the structural changes in the catalyst system with the presence of MgO. Slightly better performance was observed for the Co-Mg-Al-Ox catalyst compared to Ni-Mg-Al-Ox catalyst, due to its stronger basicity per site owing to better interaction between Co and MgO.