2026-06-01T05:32:28Zhttps://riuma.uma.es/rest/oai/request

oai:riuma.uma.es:10630/401262026-02-03T11:27:59Zcom_10630_2254col_10630_37953

Influence of second metal incorporation on nickel-based unsupported catalysts for CO2 reduction (CO2-SR) Technology Essounani-Mérida, Sofía Molina-Ramírez, Sergio Cortés-Reyes, Marina Herrera-Delgado, María Concepción Larrubia-Vargas, María Ángeles Alemany-Arrebola, Luis José Catálisis Catalizadores Metales alcalinoterreos Gases de efecto invernadero - Reducción The incorporation of alkali or alkaline-earth metals in unsupported Ni-based catalyst was analyzed as a strategy for high-temperature CO2 storage and chemical regeneration via methane, within the framework of CO2 storage–regeneration (CO2-SR) technology. It was observed that the addition of Ba, Ca, Sr and K into the Ni-catalyst modifies not only the textural but also the electronic properties of the catalysts. A restructuring of the unsupported oxide surface occurs by the reduction of the modified Ni-oxide catalyst when exposed to a H2-atmosphere at high temperature (600 °C). Upon oxygen release from NiO lattice, the alkali metals favor the reduction and stabilization of these Ni-metallic species. In such a way, nickel-metallic particles are formed from the NiO-bulk, thus generating unsupported metal catalysts; stabilized by interaction with alkali metals and anchored on the surface. The presence of Ba, Ca, Sr or K in the Ni-based catalyst formulation influences the CO2 storage capacity and regeneration by conversion employing CH4 registering the trend Ca>Ba>K>Sr for the catalytic activity at 600 °C in term of CO2 removal capacity and CH4 conversion. 2025-10-08T09:40:36Z 2025-10-08T09:40:36Z 2025-04-12 journal article Results in Engineering Volume 26, June 2025, 104921 https://hdl.handle.net/10630/40126 10.1016/j.rineng.2025.104921 eng PID2021-124098OB-I00 http://creativecommons.org/licenses/by-nc-nd/4.0/ open access Attribution-NonCommercial-NoDerivatives 4.0 Internacional Elsevier