Single crystals of the molecular sieve, MnAPO-5, were synthesized by hydrothermal synthesis in the presence of fluoride ions. It was shown by X-ray diffraction, infrared spectroscopy, electron paramagnetic resonance s...Single crystals of the molecular sieve, MnAPO-5, were synthesized by hydrothermal synthesis in the presence of fluoride ions. It was shown by X-ray diffraction, infrared spectroscopy, electron paramagnetic resonance spectroscopy, electron probe analysis and chemical composition analysis that the structure of MnAPO-5 is of the A1PO-5 type, and manganese(Ⅱ) is incorporated into the framework. Adsorption properties, thermal stability and surface acidity were also investigated.展开更多
Small-crystal TS-1 was synthesized via a seed-induced approach using ammonia as the alkali source and tetrapropylammonium bromide as an auxiliary structure-directing agent. The TS-1 samples were characterized using X-...Small-crystal TS-1 was synthesized via a seed-induced approach using ammonia as the alkali source and tetrapropylammonium bromide as an auxiliary structure-directing agent. The TS-1 samples were characterized using X-ray diffraction, N2 adsorption-desorption, Fourier-transform infrared spectroscopy, inductively coupled plasma atomic emission spectroscopy, scanning electron microscopy, and ultraviolet-visible spectroscopy. The use of the colloidal seed reduced the crystal size, and an appropriate amount of silicalite-1 seed assisted Ti incorporation into the TS-1 framework. This method reduces the cost of TS- 1 synthesis because a significantly smaller amount of tetrapropylammonium hydroxide is used. The catalytic performance of the synthesized small-crystal TS-1 samples in cyclohexanone ammoximation was better than that of bulk TS-1 as a result of improved diffusion and a larger number of active tetrahedral Ti centers.展开更多
Using tetrapropylammonium bromide(TPABr)as a template,molecular sieve Ni-ZSM-5 and its single crystals were synthesized in a nonalkaline system in the presence of fluoride ions.By means of XRD,IR,EPMA,MAS NMR,EPR,DTA ...Using tetrapropylammonium bromide(TPABr)as a template,molecular sieve Ni-ZSM-5 and its single crystals were synthesized in a nonalkaline system in the presence of fluoride ions.By means of XRD,IR,EPMA,MAS NMR,EPR,DTA and H_2-TPR techniques,it is proved that the hetero-atom,nickel,is really located in the zeolite framework.And finally,Ni-ZSM-5 was found to have high catalytic cracking reactivity.展开更多
Aluminophosphate(AlPO)and silicoaluminophosphate(SAPO)molecular sieves are an important class of open-framework crystalline materials with wide applications thanks to their molecular-scale selectivity,moderate/strong ...Aluminophosphate(AlPO)and silicoaluminophosphate(SAPO)molecular sieves are an important class of open-framework crystalline materials with wide applications thanks to their molecular-scale selectivity,moderate/strong acidity and excellent(hydro)thermal stability.In recent decades,the manufacturing of new microporous solids with ordered structures has been widely investigated and many effective methods have been developed,which enriches the material types and broadens their applications beyond the traditional use as catalysts and adsorbents.However,the development on the synthesis of AlPO/SAPO molecular sieves is still insufficient and lags behind the needs of applications.Herein,we summarize the work on the seed-assisted synthesis of AlPO/SAPO molecular sieves compared with the zeolite synthetic system,aiming to prompt the synthesis and application of AlPO/SAPO molecular sieves.展开更多
文摘Single crystals of the molecular sieve, MnAPO-5, were synthesized by hydrothermal synthesis in the presence of fluoride ions. It was shown by X-ray diffraction, infrared spectroscopy, electron paramagnetic resonance spectroscopy, electron probe analysis and chemical composition analysis that the structure of MnAPO-5 is of the A1PO-5 type, and manganese(Ⅱ) is incorporated into the framework. Adsorption properties, thermal stability and surface acidity were also investigated.
基金supported by the National Natural Science Foundation of China(21403070 and 21373088)Innovation Program of Shanghai Municipal Education Commission(13zz038)+2 种基金Key Project of the Shanghai Committee of Science and Technology(12JC1403600)National Key Technology R&D Program(2012BAE05B02)Shanghai Leading Academic Discipline Project(B409)~~
文摘Small-crystal TS-1 was synthesized via a seed-induced approach using ammonia as the alkali source and tetrapropylammonium bromide as an auxiliary structure-directing agent. The TS-1 samples were characterized using X-ray diffraction, N2 adsorption-desorption, Fourier-transform infrared spectroscopy, inductively coupled plasma atomic emission spectroscopy, scanning electron microscopy, and ultraviolet-visible spectroscopy. The use of the colloidal seed reduced the crystal size, and an appropriate amount of silicalite-1 seed assisted Ti incorporation into the TS-1 framework. This method reduces the cost of TS- 1 synthesis because a significantly smaller amount of tetrapropylammonium hydroxide is used. The catalytic performance of the synthesized small-crystal TS-1 samples in cyclohexanone ammoximation was better than that of bulk TS-1 as a result of improved diffusion and a larger number of active tetrahedral Ti centers.
文摘Using tetrapropylammonium bromide(TPABr)as a template,molecular sieve Ni-ZSM-5 and its single crystals were synthesized in a nonalkaline system in the presence of fluoride ions.By means of XRD,IR,EPMA,MAS NMR,EPR,DTA and H_2-TPR techniques,it is proved that the hetero-atom,nickel,is really located in the zeolite framework.And finally,Ni-ZSM-5 was found to have high catalytic cracking reactivity.
基金This work was supported by the National Natural Science Foundation of China(Nos.21991090,21991091,22171259)the Innovation Research Foundation of Dalian Institute of Chemical Physics,Chinese Academy of Sciences(No.DICP I201909).
文摘Aluminophosphate(AlPO)and silicoaluminophosphate(SAPO)molecular sieves are an important class of open-framework crystalline materials with wide applications thanks to their molecular-scale selectivity,moderate/strong acidity and excellent(hydro)thermal stability.In recent decades,the manufacturing of new microporous solids with ordered structures has been widely investigated and many effective methods have been developed,which enriches the material types and broadens their applications beyond the traditional use as catalysts and adsorbents.However,the development on the synthesis of AlPO/SAPO molecular sieves is still insufficient and lags behind the needs of applications.Herein,we summarize the work on the seed-assisted synthesis of AlPO/SAPO molecular sieves compared with the zeolite synthetic system,aiming to prompt the synthesis and application of AlPO/SAPO molecular sieves.
