Biogas dry reforming for syngas production: catalytic performance of nickel supported on waste-derived SiO2

SiO₂ synthesized from photovoltaic waste by a vapor-phase hydrolysis method was applied as a support for a nickel catalyst in a biogas dry reforming process for the first time. The catalytic performance was compared with those of commercial precipitated SiO₂ and ordered mesoporous SiO₂. Nickel supported on waste-derived SiO₂ exhibited high CH₄ conversion (92.3%) and high CO₂ conversion (95.8%) at 800 °C, and there was no deactivation after a 40 h-on-stream test. Catalyst characterization results revealed that the S_BET values and pore properties of catalysts affected the catalytic performance. A higher pore volume/S_BET ratio led to a smaller crystal metal size and higher metal dispersion, thus the catalyst was less prone to deactivation. This discovery will help improve catalyst design. The use of nickel supported on waste-derived SiO₂, which is competitive with commercial and mesoporous catalysts, shows the use of photovoltaic waste as a high value-added product; it can also deliver a cheap and environmentally benign support for catalysts in the biogas dry reforming process.