Research Progress on Supports for Rh-Based Catalysts in Heterogeneous Hydroformylation of Olefins
Olefin hydroformylation is a pivotal process for synthesizing high-value-added aldehydes, with applications extending from short-chain to long-chain olefins (C6+). Traditional homogeneous catalytic systems suffer from difficulties in separating and recovering precious rhodium (Rh), driving research toward heterogeneous catalytic systems. This review summarizes recent progress in supports for heterogeneous Rh-based catalysts, focusing on the influence of structural regulation strategies of inorganic oxide-supported, porous carbon-supported, organic porous polymer-based, zeolite-supported, and composite-supported catalysts on active site dispersion, regioselectivity, and cycle stability. Key findings include enhanced linear-to-branched (n/i) ratios and turnover frequencies (TOF) achieved through tailored support design. For instance, Rh1/CeO2 with morphology effects demonstrates molecular-level understanding of support effects, while Rh/activated carbon with surface oxygen groups improves catalytic performance in 1-hexene hydroformylation. Porous monophosphine polymers confine atomically dispersed Rh, achieving regioselective hydroformylation. Additionally, Rh-N4 single atoms and Rh clusters dual-active sites on supports yield ultra-high TOF. The review aims to provide insights for rational design of high-performance heterogeneous hydroformylation catalysts, addressing industrial challenges of catalyst recovery and stability.