Hydrogen-Rich Gas Production by Steam Reforming and Oxidative Steam Reforming of Methanol over La<sub>0.6</sub>Sr<sub>0.4</sub>CoO<sub>3−δ</sub>: Effects of Preparation, Operation Conditions, and Redox Cycles
M. Morales, M. Laguna, E. Jiménez‐Piqué
Abstract
High Resolution Image Download MS PowerPoint Slide La 0.6 Sr 0.4 CoO 3−δ (LSC) perovskite, as a potential catalyst precursor for hydrogen (H 2 )-rich production by steam reforming of methanol (SRM) and oxidative steam reforming of methanol (OSRM), was investigated. For this purpose, LSC was synthesized by the citrate sol–gel method and characterized by complementary analytical techniques. The catalytic activity was studied for the as-prepared and prereduced LSC and compared with the undoped LaCoO 3−δ (LCO) at several feed gas compositions. Furthermore, the degradation and regeneration of LSC under repeated redox cycles were studied. The results evidenced that the increase in the water/methanol ratio under SRM, and the O 2 addition under OSRM, increased the CO 2 formation and decreased both the H 2 selectivity and catalyst deactivation caused by carbon deposition. Methanol conversion of the prereduced LSC was significantly enhanced at a lower temperature than that of as-prepared LSC and undoped LCO. This was attributed to the performance of metallic cobalt nanoparticles highly dispersed under reducing atmospheres. The reoxidation program in repetitive redox cycles played a crucial role in the regeneration of catalysts, which could be regenerated to the initial perovskite structure under a specific thermal treatment, minimizing the degradation of the catalytic activity and surface.