Lengthening alkyl spacers to increase SBA-15-anchored Rh-P complex activities in 1-octene hydroformylation

摘要

The alkyl spacer was lengthened In heterogenizing a Rh-P complex into mesoporous silicate SBA-15 to increase the immobilized catalyst activities in 1-octene hydroformylation.rnHeterogenization of organometallic catalysts into mesoporous molecular sieves has been so far extensively studied. In traditional immobilized catalysts, the metal is stiffly anchored to the support through short organic groups as spacers Although the difficulty in catalyst separation has been hence overcome, the immobilized catalysts usually reveal decreased activities than homogeneous counterparts. In heterogeneous cases, active sites are localized; reactant molecules are supposed to approach to the solid surface, to be adsorbed by the active site, and then to be activated. Mass transfer thus greatly affects the reaction efficiency.