Structure–Reactivity\nRelationship of Zeolite-Confined\nRh Catalysts for Hydroformylation of Linear α‑Olefins

Substituting the molecular metal complexes used in the\nindustrial\nolefin hydroformylation process is of great significance in fundamental\nresearch and practical application. One of the major difficulties\nin replacing the classic molecular metal catalysts with supported\nmetal catalysts is the low chemoselectivity and regioselectivity of\nthe supported metal catalysts because of the lack of a well-defined\ncoordination environment of the metal active sites. In this work,\nwe have systematically studied the influences of key factors (crystallinity,\nalkali promoters, etc.) of the Rh-MFI zeolite catalysts on their performances\nfor the hydroformylation of long-chain α-olefins (LAOs). With\nthe help of comprehensive spectroscopy and electron microscopy characterization\nresults, we can correlate the structural features of various Rh-MFI\ncatalysts and their catalytic performances. The resultant structure–reactivity\nrelationship guides us to prepare a nanosized Rh-MFI catalyst, which\nexhibits about a 3-fold improvement in specific activity compared\nto the Rh-MFI catalyst with conventional crystallite sizes and maintains\nvery high regioselectivity for hydroformylation of LAOs.