Hydrogen production from dry reforming of methane, using CO previously chemisorbed in the LiZnNiO solid solution.

LiZnO was chemically modified by nickel addition, in order to develop different compositions of the solid solution LiZnNiO. These materials were evaluated bifunctionally; analyzing their CO capture performances, as well as on their catalytic properties for H production via dry reforming of methane (DRM). The crystal structures of LiZnNiO solid solution samples were determined through X-ray diffraction, which confirmed the integration of nickel ions up to a concentration around 20 mol%, meanwhile beyond this value, a secondary phase was detected. These results were supported by XPS and TEM analyses. Then, dynamic and isothermal thermogravimetric analyses of CO capture revealed that LiZnNiO solid solution samples exhibited good CO chemisorption efficiencies, similarly to the pristine LiZnO chemisorption trends observed. Moreover, a kinetic analysis of CO isothermal chemisorptions, using the Avrami-Erofeev model, evidenced an increment of the constant rates as a function of the Ni content. Since Ni ions incorporation did not reduce the CO capture efficiency and kinetics, the catalytic properties of these materials were evaluated in the DRM process. Results demonstrated that nickel ions favored hydrogen (H) production over the pristine LiZnO phase, despite a second H production reaction was determined, methane decomposition. Thereby, LiZnNiO ceramics can be employed as bifunctional materials.