화학공학소재연구정보센터
Catalysis Letters, Vol.149, No.10, 2794-2806, 2019
Synthesis of Convertible {PO4[WO3 reversible arrow W(O)(2)(O-2)](4)}-DMA16 in SBA-15 Nanochannels and Its Catalytic Oxidation Activity
A phase transfer catalyst ({PO4[WO3](4)}-DMA16) had been first synthesized and stabilized in mesochannels of (3-chloropropyl)trimethoxysilane-functionalized mesoporous silica SBA-15 to build an active nano-environment for triphase cyclohexene oxidation. Tungsten precursor ({PO4[WO3](4)}(3-)) and organic amino N,N-dimethylhexadecan-1-amine (DMA16) self-assembled in channels of SBA-15 to form a hybrid catalyst {PO4[WO3](4)}-DMA16-SBA-15, which combined advantages of homogeneous and heterogeneous catalysts. Insoluble {PO4[WO3](4)}-DMA16 formed soluble {PO4[W(O)(2)(O-2)](4)}-DMA16 active species with the aid of H2O2, and when H2O2 was consumed out, {PO4[WO3](4)}-DMA16 was recombined. In addition, free remaining organic moieties (-Cl and -DMA16) on the surface of SBA-15 allowed {PO4[WO3](4)}-DMA16-SBA-15 catalyst possessed more hydrophobic surface property, which further facilitated the compatibility between organic reactant cyclohexene and inorganic H2O2 molecules. The easy reusability of {PO4[WO3](4)}-DMA16-SBA-15 catalyst for five catalytic runs without distinct change in catalytic activity was a significant green attribute of this catalyst. [GRAPHICS] .