Thermochemical syngas generation via solid looping process: An experimental demonstration using Fe-based material

Chemical looping is investigated for the production of syngas via reforming or reverse water gas shift in a packed bed reactor using 500 g of Fe on Al₂O₃ was demonstrated. Oxidation, reduction of the OC and subsequent catalytic reactions of reforming or reverse water gas shift were examined in a temperature range of 600–900 °C and a pressure range of 1–3 bar_a at high flowrate. Different inlet gas compositions were explored for the considered gas–solid and catalytic reaction stages. Oxidation with air successfully heated the reactor. CH₄ resulted ineffective at reducing the Fe-based oxygen carrier while H₂ and CO-rich stream were able to achieve full reduction to FeO of the material. In terms of catalytic activity, the maximum conversion of CH₄ achieved during the reforming was limited to 62.8 % at 900 °C and 1 bar_a. Thermally integrated chemical looping reverse water gas shift was studied as option for CCU in combination with green H₂ to produce renewable fuels. A H₂/CO value of 2 could be achieved by feeding H₂/CO₂ of 2. The pressure did not substantially affect the conversion and the bed did not present carbon deposition. The ability of a Fe-based packed bed chemical looping reactor to recover after the carbon deposition was also explored. It was found that using a mixture of CH₄ and CO₂ achieved 92% recovery of the original capacity.