Design, Synthesis, Characterization and Catalytic Activity of Chromium Oxide Nanoparticles Immobilized on Layered Double Hydroxide as Competent Nanocatalyst

Transition metals are commonly used in the oxidation of cyclohexane, but their harsh reaction conditions and lack of efficiency make further use challenging. In this study, we prepared chromium nanoparticles supported on layered double hydroxide abbreviated as Cr2O3/LDH. The physiochemical properties of synthesized nanocatalysts were extensively studied using FTIR, XRD, SEM, EDX, TEM, ICP-AES, and XPS technique. The synthesized Cr2O3/LDH nanocatalyst was used to the liquid phase selective oxidation of cyclohexane under solvent-free condition. The characterization result indicates that the Cr2O3-NPs were uniformly dispersed on the surface of LDH. The Cr2O3-NPs alone have relatively low catalytic activity, while LDH has no catalytic activity. However, the Cr2O3-NPs/LDH hybrid significantly increases both the conversion and selectivity. A maximum conversion of 34.73% cyclohexane and 97.85% selectivity to KA oil obtained over the Cr2O3/LDH nanocatalyst. Furthermore, the leaching test showed that the Cr2O3/LDH nanocatalyst was heterogeneous and could be recycled at least six cycles without significant loss in catalytic efficiency. [GRAPHICS]