The Role of Strontium as an Economic Promoter Over WO3 + ZrO2 Supported Ni Catalyst for H2 Production Through Dry Reforming of Methane.

Group II Metal oxide of the periodic table has always been the attention of the catalytic community due to its basicity as well as low cost. The role of Sr as a promoter over WO3 + ZrO2 supported Ni is investigated for dry reforming of methane (DRM). The catalyst is characterized by X-ray powder diffraction, surface area, porosity, temperature-programmed oxidation/reduction/desorption techniques, infrared-Raman spectroscopy and thermogravimetry. H2TPR–CO2TPD–H2TPR cyclic experiments show the stabilization of active sites (metallic Ni) under DRM feed. CO2-TPO shows the oxidation of carbon deposits by CO2. 2wt% Sr loading over 5Ni/WO3 + ZrO2 catalyst resulted in the organization of stable metallic Ni-sites derived from "moderately interacted NiO species" and highest density bidentate CO2-adsorbed species. It resulted in the highest 57% H2-yield at the end of 470 min. However, 3wt% Sr loading over 5Ni/WO3 + ZrO2 catalyst is found decremental due to the formation of ionic CO32− surface species, highest deposition of coke, and least surface. [ABSTRACT FROM AUTHOR]