Study on characterization and application of novel Ni-Ga based catalysts in conversion of carbon dioxide to methanol

Novel Ni-Ga based catalysts including Ni-Ga alloy, Ni-Ga/mixed oxide and Ni-Ga/mesosilica were prepared through metal melting, co-condensation-evaporation and impregnation methods, respectively. These three methods, by the above order, were established at temperatures of 1500 °C for 3 hours, 70 °C for 24 hours and room temperature overnight, respectively. The activity of these catalysts were studied in methanol synthesis from CO2. Results showed that the Ni-Ga alloy, Ni-Ga/mixed oxides and Ni-Ga/mesosilica catalysts mostly contained the multiple crystal phases, the active sites of crystalline δ-Ni5Ga3 distributed on Ni-Ga mixed oxide, and the active sites of crystalline δ-Ni5Ga3 distributed on mesosilica support, respectively. The Ni-Ga/mesosilica catalyst showed the highest activity in the conversion of CO2 to CH3OH. The catalyst structures and properties were characterized by SAXRD, WAXRD, SEM, TEM and XPS techniques. Gas products were determined by GC coupled with either TCD or FID for inorganic or organic compound, respectively.