Plasmatron-assisted reforming of CO2 and CH4 under catalyst combined with steam to generate hydrogen-rich fuel gas.

Synthesis gas (CO + H2), or syngas, is an environmentally friendly fuel that can be produced from coal, oil, natural gas, biomass, and solid recovered fuels (SRF). Methane (CH4) and carbon dioxide (CO2) are major greenhouse gases, and their reforming into syngas offers a promising approach for greenhouse gas mitigation. This study investigates the steam plasma-catalytic reforming of CH4 and CO2 using a thermal plasmatron coupled with catalysts and steam as a dehydrogenating agent to produce hydrogen-rich syngas. The effects of CH4/CO2 ratios (3/7-7/3), total flow rates (0.5-2.5 slpm), temperatures (573-873 K), steam injection (0-3 mL min-1), catalysts (Al2O3, Ni/Al2O3, Ni-Ce/Al2O3), and space velocities (3072-9215 h-1) were examined. Performance indicators included CH4 and CO2 conversions, CO and H2 selectivities, H2/CO ratio, H2 yield, and energy conversion efficiency (ECE). The Ni-Ce/Al2O3 catalyst improved CH4 and CO2 conversions from 95.12% and 86.22% to 98.33% and 91.7%, respectively. With steam addition, conversions and CO yield slightly decreased, but the H2 yield and H2/CO ratio increased markedly to 192.5% and 3.39, indicating high-purity hydrogen formation. The plasma energy demand can be supplied by renewable energy sources, and CH4 and CO2 feedstocks can be derived from biomass or waste incineration, highlighting the potential of this process for sustainable fuel production.