Perovskite-Type LaCoO 3 as an Efficient and Green Catalyst for Sustainable Partial Oxidation of Cyclohexane

Abstract

Perovskite-type LaCoO3 catalysts were studied for cyclohexane oxidation with molecular oxygen in a solvent-free system. Catalysts with various Lanthanum to Cobalt molar ratios were prepared through a modified citric acid procedure and characterized by different techniques. Among all catalysts, the best cyclohexane conversion results (8.3%) with a K/A oil (cyclohexanone and cyclohexanol) selectivity of 90% were obtained over LaCoO3 with a La to Co molar ratio of 1:1. The high catalytic activity on the perovskite-type LaCoO3 catalyst was explored by experimental and theoretical methods. Density functional theory-based calculations clarified the role of La and Co ions in oxygen and cyclohexane adsorption, respectively. The characterization results indicated that a single-phase LaCoO3 perovskite with a dominance of surface Co3+ species and relatively high concentration of adsorbed oxygen species on the catalyst surface enhances the catalytic performance. This study presents insights into the design of a highly active, cost-effective, and green catalyst for cyclohexane partial oxidation.