Methanesulfonic acid(MSA) was successfully immobilized in silica, leading to a novel and environmentally friendly solid acid catalyst SMSA. The most important feature of SMSA is that anhydrous formic acid is used to h...Methanesulfonic acid(MSA) was successfully immobilized in silica, leading to a novel and environmentally friendly solid acid catalyst SMSA. The most important feature of SMSA is that anhydrous formic acid is used to hydrolysis of tetraethylorthosilicate(TEOS). No water was added in the whole preparation. Therefore, MSA could be anchored in silica matrix more effectively instead of being dissolved in water. This new organic/inorganic hybrid catalyst was characterized by powder X-ray diffraction(XRD), energy dispersive spectrum(EDS), N_2 adsorption-desorption analyzer, thermogravimetric analysis(TGA-DSC) and pyridine-FTIR. The catalytic activity was tested by alkylation of olefins and aromatics. High concentration acid sites, both Lewis and Br?nsted, abundant porosity and large surface area enabled the highest activity for SMSA, among MCM-22, ZSM-5 and industrial acidity clay.展开更多
A novel approach is designed to optimize the synthesis of sulfonic-functionalized silica material. Results from ^(29)Si and ^(27)Al NMR suggest that the Al acts as the bridging atom connecting the methanesulfonate and...A novel approach is designed to optimize the synthesis of sulfonic-functionalized silica material. Results from ^(29)Si and ^(27)Al NMR suggest that the Al acts as the bridging atom connecting the methanesulfonate and silica matrix. Further pyridine-FTIR spectra followed by catalytic activity tests demonstrate that compared with previous methods, our new approach results in higher Lewis acid site concentration, higher thermal stability and superior catalytic activity. Moreover, the whole catalysis preparation procedure is environmentally friendly. Specifically, the silica matrix is synthesized through hydrolysis of tetraethylorthosilicate employing formic acid as hydro-catalyst, in which no surfactant species or precursors were involved.展开更多
文摘Methanesulfonic acid(MSA) was successfully immobilized in silica, leading to a novel and environmentally friendly solid acid catalyst SMSA. The most important feature of SMSA is that anhydrous formic acid is used to hydrolysis of tetraethylorthosilicate(TEOS). No water was added in the whole preparation. Therefore, MSA could be anchored in silica matrix more effectively instead of being dissolved in water. This new organic/inorganic hybrid catalyst was characterized by powder X-ray diffraction(XRD), energy dispersive spectrum(EDS), N_2 adsorption-desorption analyzer, thermogravimetric analysis(TGA-DSC) and pyridine-FTIR. The catalytic activity was tested by alkylation of olefins and aromatics. High concentration acid sites, both Lewis and Br?nsted, abundant porosity and large surface area enabled the highest activity for SMSA, among MCM-22, ZSM-5 and industrial acidity clay.
文摘A novel approach is designed to optimize the synthesis of sulfonic-functionalized silica material. Results from ^(29)Si and ^(27)Al NMR suggest that the Al acts as the bridging atom connecting the methanesulfonate and silica matrix. Further pyridine-FTIR spectra followed by catalytic activity tests demonstrate that compared with previous methods, our new approach results in higher Lewis acid site concentration, higher thermal stability and superior catalytic activity. Moreover, the whole catalysis preparation procedure is environmentally friendly. Specifically, the silica matrix is synthesized through hydrolysis of tetraethylorthosilicate employing formic acid as hydro-catalyst, in which no surfactant species or precursors were involved.