Green Hydrogen\nProduction by Chemical Looping Reforming\nof Wheat Straw Pyrolysis Volatiles via LaNi<sub><i>x</i></sub>Fe<sub>1–<i>x</i></sub>O<sub>3</sub>@SBA-15

Using zero-carbon resource biomass with wide sources\nand abundant\nreserves as raw materials is of great significance for the sustainable\ndevelopment of energy and the environment to produce hydrogen with\ngreen and low carbon. In this study, a LaNi<sub><i>x</i></sub>Fe<sub>1–<i>x</i></sub>O<sub>3</sub>@SBA-15\nperovskite oxygen carrier with strong oxygen storage capacity and\ncontrollable lattice transport was prepared, which was used in the\nchemical looping reforming process of total components of wheat straw\npyrolysis volatiles, and it is expected to realize the efficient production\nof green hydrogen. With volatile conversion, syngas selectivity, and\nH<sub>2</sub>/CO as responses, orthogonal experiments were designed\nand carried out based on the multifactor response surface analysis\nmethod to analyze the interaction between factors. The results showed\nthat Ni doping reduced the metal–oxygen bond’s binding\nenergy and improved lattice oxygen’s mobility. LaNi<sub>0.8</sub>Fe<sub>0.2</sub>O<sub>3</sub>@S was considered the best oxygen carrier,\nwhose volatile conversion and syngas selectivity were 98.0 and 84.5%\nand the output of H<sub>2</sub> and syngas was 544.9 and 880.2 mL·g<sup>–1</sup>, respectively. Multifactor response surface analysis\nshowed that temperature was the key factor of volatile chemical looping\nreforming, and there was a strong interaction between the amount of\noxygen carriers and space velocity. The optimum reaction conditions\nwere 765 °C, 150 mL·min<sup>–1</sup>·g<sup>–1</sup>, and 0.82 g of oxygen carriers. The experimental verification showed\nthat the volatile conversion rate was 98.0%, and the predicted value\nwas 98.7%, and the predicted value was basically consistent with the\nexperimental value. Ten cycles showed that LaNi<sub>0.8</sub>Fe<sub>0.2</sub>O<sub>3</sub>@S had excellent reforming performance, the\nvolatile conversion rate had good stability with a maximum fluctuation\nof less than 2%, the selectivity of syngas remained around 84%, and\nthe CH<sub>4</sub> content remained within 2%. This study provided\na certain experimental basis for the preparation of green hydrogen\nby chemical looping reforming of biomass pyrolysis volatiles.