Ni/SiO2 core-shell catalysts for catalytic hydrogen production from waste plastics-derived syngas

Ni/SiO2 core-shell catalysts were prepared by deposition-precipitation method and used to produce hydrogen from waste plastics-derived syngas. The SiO2 core synthesized by the Stöber process was used as the support. This core was synthesized using various solvents, and the effect of these solvents on the morphologies and catalytic performance of the Ni/SiO2 core-shell catalysts was investigated. The synthesis parameters of the Ni/SiO2 catalysts were further investigated to enhance the metal-support interaction and dispersion of Ni on the SiO2 support. The highest catalytic activity of 181 mmol/g-h was achieved when the Ni/SiO2 core-shell catalyst was synthesized in methanol (Ni/SiO2-M) and reacted at 800 °C at a water-addition rate of 0.75 g-H2O/h. The Ni/SiO2-M catalyst, which possessed strong metal-support interaction nickel phyllosilicates, high specific area, small particle size, and homogeneous metal dispersion, exhibited the best long-term stability.