Preparation of Co schiff base complex immobilized on MCM\|41 by the 3\|aminopropyltriethoxysilane modified mesoporous molecular sieve MCM\|41 reacted with cobalt nitrate and salicylaldehyde. Such cobalt schiff base co...Preparation of Co schiff base complex immobilized on MCM\|41 by the 3\|aminopropyltriethoxysilane modified mesoporous molecular sieve MCM\|41 reacted with cobalt nitrate and salicylaldehyde. Such cobalt schiff base complex immobilized on MCM\|41 could be used as the catalyst, with O\-2 as the oxidant and isobutyraldehyde as the sacrificial reagent, to catalyze the epoxidation of cyclohexene and styrene in CH3CN. After 4h of reaction, the conversion of cyclohexene reached 98% and the selectivity to epoxy cyclohexane, 88%; the conversion of styrene reached 89% and the selectivity, 69%. In addition, the catalyst could remain its catalytic activity after several reuses.展开更多
A\} new highly ordered mesostructured silica(possible space group \%Fm3m\%) was synthesized by \{using\} tri\|headgroup quaternary ammonium surfactant \{CH\-3(CH\-2)\-\{17\}N\++(CH\-3)\-2CH\-2CH\-2N\++(CH\-3)\-2CH\-2C...A\} new highly ordered mesostructured silica(possible space group \%Fm3m\%) was synthesized by \{using\} tri\|headgroup quaternary ammonium surfactant \{CH\-3(CH\-2)\-\{17\}N\++(CH\-3)\-2CH\-2CH\-2N\++(CH\-3)\-2CH\-2CH\-2\}CH\-2N\++(CH\-3)\-3\53Br\+-(C\-\{18\|2\|3\|1\}) under a basic condition. The cubic mesoporous silica product has an \{average\} pore size of 2.9 nm, a large BET specific surface area of 991 m\+2/g and a large pore volume of \{0.98 cm\+3/g\}.展开更多
Organically modified MSU- x mesophases containing phenyl, ureidopropyl and methyl along with phenyl two moieties were directly prepared by one- pot synthesis method. Their texture and surface properties were character...Organically modified MSU- x mesophases containing phenyl, ureidopropyl and methyl along with phenyl two moieties were directly prepared by one- pot synthesis method. Their texture and surface properties were characterized by means of XRD, HRTEM, FT- IR, N2 adsorption/desorption, 29Si CPMAS NMR、 13C CPMAS NMR and the microscopic structure was also characterized by small angle X- ray scattering (SAXS) using synchrotron radiation as X- ray source. The results showed that SAXS profiles were hardly constant with Porod′ s law showing a negative slope, i.e. negative deviations (see fig.3). This suggested that the organic groups covalently linked with the matrix of mesoporous silica formed an interfacial layers, which led to the scattering of the pore distortion and gave a negative diviation from Porod′ s law. The average thickness of the interfacial layer in each sample was further obtained by analyzing this deviation. SAXS analysis also showed that the organically functionalized MSU- X displayed mass fractal and the uniform distribution of the organic groups within the mesoporous channels, implying that it′ s formation was a non- equilibrium and non- linear process.展开更多
文摘Preparation of Co schiff base complex immobilized on MCM\|41 by the 3\|aminopropyltriethoxysilane modified mesoporous molecular sieve MCM\|41 reacted with cobalt nitrate and salicylaldehyde. Such cobalt schiff base complex immobilized on MCM\|41 could be used as the catalyst, with O\-2 as the oxidant and isobutyraldehyde as the sacrificial reagent, to catalyze the epoxidation of cyclohexene and styrene in CH3CN. After 4h of reaction, the conversion of cyclohexene reached 98% and the selectivity to epoxy cyclohexane, 88%; the conversion of styrene reached 89% and the selectivity, 69%. In addition, the catalyst could remain its catalytic activity after several reuses.
文摘A\} new highly ordered mesostructured silica(possible space group \%Fm3m\%) was synthesized by \{using\} tri\|headgroup quaternary ammonium surfactant \{CH\-3(CH\-2)\-\{17\}N\++(CH\-3)\-2CH\-2CH\-2N\++(CH\-3)\-2CH\-2CH\-2\}CH\-2N\++(CH\-3)\-3\53Br\+-(C\-\{18\|2\|3\|1\}) under a basic condition. The cubic mesoporous silica product has an \{average\} pore size of 2.9 nm, a large BET specific surface area of 991 m\+2/g and a large pore volume of \{0.98 cm\+3/g\}.
文摘Organically modified MSU- x mesophases containing phenyl, ureidopropyl and methyl along with phenyl two moieties were directly prepared by one- pot synthesis method. Their texture and surface properties were characterized by means of XRD, HRTEM, FT- IR, N2 adsorption/desorption, 29Si CPMAS NMR、 13C CPMAS NMR and the microscopic structure was also characterized by small angle X- ray scattering (SAXS) using synchrotron radiation as X- ray source. The results showed that SAXS profiles were hardly constant with Porod′ s law showing a negative slope, i.e. negative deviations (see fig.3). This suggested that the organic groups covalently linked with the matrix of mesoporous silica formed an interfacial layers, which led to the scattering of the pore distortion and gave a negative diviation from Porod′ s law. The average thickness of the interfacial layer in each sample was further obtained by analyzing this deviation. SAXS analysis also showed that the organically functionalized MSU- X displayed mass fractal and the uniform distribution of the organic groups within the mesoporous channels, implying that it′ s formation was a non- equilibrium and non- linear process.
