Na/CaFe2O4 catalysts for efficient CO2 hydrogenation to light olefins: Composition effects and catalytic mechanisms

Abstract

Spinel-structured catalysts, with flexible frameworks and adjustable compositions, enhance catalytic performance by creating active sites. During CO₂ hydrogenation, these catalysts promote CO₂ bond cleavage and activation. This paper investigates the performance of the spinel-type catalyst Na/CaFe₂O₄, achieving a 39.29 % selectivity for light olefins and a conversion rate of 49.72 %. Data analysis showed that adding Ca increased the concentration of strong basic sites and oxygen vacancies in the catalysts, enhancing CO₂ conversion. Additionally, Na and Ca facilitated the dissociative adsorption of C-O bonds and subsequent C-C coupling, improving the catalytic efficiency of CO₂ hydrogenation. The catalyst demonstrated exceptional stability over 72 h, suggesting its promising industrial applicability.