SAPO-34 was synthesized with n-butylamine(BA) as a template for the first time.Crystallization temperature and initial Si amount were important factors leading to successful syntheses.Lamellar AlPO-kanemite tends to...SAPO-34 was synthesized with n-butylamine(BA) as a template for the first time.Crystallization temperature and initial Si amount were important factors leading to successful syntheses.Lamellar AlPO-kanemite tends to form as the major phase or as an impurity of SAPO-34 at lower crystallization temperatures,though a higher initial Si amount may offer a positive effect on the crystallization of SAPO-34 that mitigates the low temperature.Higher temperature(240℃) can effectively suppress the generation of lamellar materials and allow the synthesis of pure SAPO-34 with a wider range of Si incorporation.The crystallization processes at 200 and 240℃ were investigated and compared.We used the aminothermal method to synthesize SAPO-34-BA at 240℃ and also found n-propylamine is a suitable template for the synthesis of SAPO-34.The SAPO-34-BA products were characterized by many techniques.SAPO-34-BA has good thermal stability,crystallinity and porosity.BA remained intact in the crystals with ~1.8 BA molecule per chabazite cage.The catalytic performance of SAPO-34 was tested in the methanol amination reaction,which showed high methanol conversion and selectivity for methylamine plus dimethylamine under the conditions investigated,suggesting that this material is a good candidate for the synthesis of methylamines.展开更多
The photodissociation dynamics of 2-bromobutane has been investigated at 264.77 and 264.86 nm by ion-velocity map imaging technique coupled with resonance-enhanced multi- photon ionization. The speed and angular distr...The photodissociation dynamics of 2-bromobutane has been investigated at 264.77 and 264.86 nm by ion-velocity map imaging technique coupled with resonance-enhanced multi- photon ionization. The speed and angular distributions have been derived from the velocity map images of Br and Br^*. The speed distributions of Br and Br^* atoms in the photodis- sociation of 2-bromobutane at -265 nm can be fitted using only one Gaussian function indicating that bromine fragments were produced via direct dissociation of C-Br bond. The contributions of the excited 3^Q0, 3Q1, and 1^Q1 states to the products (Br and Br^*) were discussed. It is found that the nonadiabatic 1^Q1←3^Q0 transition plays an important role for Br photofragment in the dissociation of 2-C4HgBr at -265 nm. Relative quantum yield of 0.621 for Br(2P3/2) at -265 nm in the photodissociation of 2-bromobutane is derived. By comparing the photodissociation of 2-C4H9Br at -265 nm and that that at-234 nm, the anisotropy parameter β(Br) and β(Br^*), and relative quantum yield Ф(Br) decrease with increasing wavelength, the probability of curve crossing between 3 ^Q0 and 1^Q1 decreases with increasing laser wavelength.展开更多
The acid-functionalized ionic liquid([HSO3Pmim]HSO4) was synthesized by a two-step method. Nuclear magnetic resonance(NMR) and Fourier transform infrared spectroscopy(FT-IR) show that the synthesis method is feasible ...The acid-functionalized ionic liquid([HSO3Pmim]HSO4) was synthesized by a two-step method. Nuclear magnetic resonance(NMR) and Fourier transform infrared spectroscopy(FT-IR) show that the synthesis method is feasible and high purity of ionic liquid can be obtained. Using [HSO3Pmim]HSO4as the catalyst, we studied the reaction kinetics of synthesizing sec-butyl alcohol from sec-butyl acetate and methanol by transesterification in a high-pressure batch reactor. The effects of temperature, initial molar ratio of methanol to ester, and catalyst concentration on the conversion of sec-butyl acetate were studied. Based on its possible reaction mechanism, a homogeneous kinetic model was established. The results show that the reaction heat ΔH is 10.94 × 103J·mol-1, so the reaction is an endothermic reaction. The activation energies Ea+and Ea-are 60.38 × 103 and 49.44 × 103J·mol-1,respectively.展开更多
A convergent construction of [2,3]-fused indoline tetrahydropyridazines via an I2/tert-butyl hydroperoxide(TBHP) catalyzed three-component dearomative oxidative coupling of indoles, hydrazines and acetophenone was est...A convergent construction of [2,3]-fused indoline tetrahydropyridazines via an I2/tert-butyl hydroperoxide(TBHP) catalyzed three-component dearomative oxidative coupling of indoles, hydrazines and acetophenone was established in moderate to good yields. This protocol provides a new approach for the synthesis of these biologically interesting fused indolines.展开更多
基金supported by the National Natural Science Foundation of China(21676262,21476228,21506207)the Key Research Program of Frontier Sciences of CAS(QYZDB-SSW-JSC040)~~
文摘SAPO-34 was synthesized with n-butylamine(BA) as a template for the first time.Crystallization temperature and initial Si amount were important factors leading to successful syntheses.Lamellar AlPO-kanemite tends to form as the major phase or as an impurity of SAPO-34 at lower crystallization temperatures,though a higher initial Si amount may offer a positive effect on the crystallization of SAPO-34 that mitigates the low temperature.Higher temperature(240℃) can effectively suppress the generation of lamellar materials and allow the synthesis of pure SAPO-34 with a wider range of Si incorporation.The crystallization processes at 200 and 240℃ were investigated and compared.We used the aminothermal method to synthesize SAPO-34-BA at 240℃ and also found n-propylamine is a suitable template for the synthesis of SAPO-34.The SAPO-34-BA products were characterized by many techniques.SAPO-34-BA has good thermal stability,crystallinity and porosity.BA remained intact in the crystals with ~1.8 BA molecule per chabazite cage.The catalytic performance of SAPO-34 was tested in the methanol amination reaction,which showed high methanol conversion and selectivity for methylamine plus dimethylamine under the conditions investigated,suggesting that this material is a good candidate for the synthesis of methylamines.
基金ACKNOWLEDGMENTS This work was supported by the National Natural Science Foundation of China (No.21073177 and No.20873133), the Ministry of Science and Technology of China (No.2007CB815203 and No.2010CB923302), the Chinese Academy of Sciences (No.KJCX2-YW- N24 and No.KJCX2-EW-W09), the Fundamental Research Funds for the Central Universities of China (No.WK2340000012), and the USTC-NSRL Joint Funds (No.KY2340000021).
文摘The photodissociation dynamics of 2-bromobutane has been investigated at 264.77 and 264.86 nm by ion-velocity map imaging technique coupled with resonance-enhanced multi- photon ionization. The speed and angular distributions have been derived from the velocity map images of Br and Br^*. The speed distributions of Br and Br^* atoms in the photodis- sociation of 2-bromobutane at -265 nm can be fitted using only one Gaussian function indicating that bromine fragments were produced via direct dissociation of C-Br bond. The contributions of the excited 3^Q0, 3Q1, and 1^Q1 states to the products (Br and Br^*) were discussed. It is found that the nonadiabatic 1^Q1←3^Q0 transition plays an important role for Br photofragment in the dissociation of 2-C4HgBr at -265 nm. Relative quantum yield of 0.621 for Br(2P3/2) at -265 nm in the photodissociation of 2-bromobutane is derived. By comparing the photodissociation of 2-C4H9Br at -265 nm and that that at-234 nm, the anisotropy parameter β(Br) and β(Br^*), and relative quantum yield Ф(Br) decrease with increasing wavelength, the probability of curve crossing between 3 ^Q0 and 1^Q1 decreases with increasing laser wavelength.
基金Supported by the New Century Excellent Talents in Fujian Province(JA12014)the Natural Science Foundation for Distinguished Young Scholars of Fujian(2014J06004)
文摘The acid-functionalized ionic liquid([HSO3Pmim]HSO4) was synthesized by a two-step method. Nuclear magnetic resonance(NMR) and Fourier transform infrared spectroscopy(FT-IR) show that the synthesis method is feasible and high purity of ionic liquid can be obtained. Using [HSO3Pmim]HSO4as the catalyst, we studied the reaction kinetics of synthesizing sec-butyl alcohol from sec-butyl acetate and methanol by transesterification in a high-pressure batch reactor. The effects of temperature, initial molar ratio of methanol to ester, and catalyst concentration on the conversion of sec-butyl acetate were studied. Based on its possible reaction mechanism, a homogeneous kinetic model was established. The results show that the reaction heat ΔH is 10.94 × 103J·mol-1, so the reaction is an endothermic reaction. The activation energies Ea+and Ea-are 60.38 × 103 and 49.44 × 103J·mol-1,respectively.
基金supported by the Ministry of Science and Technology(2016YFA0602900)the National Natural Science Foundation of China(21372224,21232008,21420102003,21521002)+1 种基金Shandong Province Independent Innovation and Achievements Transformation of Special(2014XGC06001)the Chinese Academy of Sciences
文摘A convergent construction of [2,3]-fused indoline tetrahydropyridazines via an I2/tert-butyl hydroperoxide(TBHP) catalyzed three-component dearomative oxidative coupling of indoles, hydrazines and acetophenone was established in moderate to good yields. This protocol provides a new approach for the synthesis of these biologically interesting fused indolines.