MICROCALORIMETRIC STUDY OF THE ACIDITY AND BASICITY OF NI SIO2 CATALYSTS MODIFIED BY METALLIC ADDITIVES FE, CO, ZR AND CE/

The acidity and basicity of silica-supported nickel catalysts modified by metallic additives such as Fe, Co, Zr and Ce have been determined by adsorption microcalorimetry. These catalysts have been tested in th e catalytic reforming of methane with carbon dioxide. The results indi cate that the metallic additives modify noticeably the acidity of the Ni/SiO2 catalysts, the acidity increasing in the order: Ni-Ce < Ni < N i-Co < Ni-Fe < Ni-Zr. Moreover, it was demonstrated that the most acti ve catalyst in the CH4 + CO2 reaction is the least acidic, namely, Ni- Ce/SiO2. (C) 1997 Elsevier Science B.V.