Pure Mesoporous TiO2 molecular sieves (Ti-TMS) were synthesized with different templates for the first time and the templates can be successfully removed by refluxing the samples in the EtOH/H2O/KOH solution. The XRD ...Pure Mesoporous TiO2 molecular sieves (Ti-TMS) were synthesized with different templates for the first time and the templates can be successfully removed by refluxing the samples in the EtOH/H2O/KOH solution. The XRD pattern and TEM confirm that the uniformity and stability of Ti-TMS2 synthesized with dodecylamine as template is obviously inferior to that of Ti-TMS1 prepared with dodecylphosphate and hexadecylphosphate as templates. Furthermore, after the templates were removed, the mesostructure of Ti-TMS1 was preserved to a great degree than that of Ti-TMS2.展开更多
The ordered mesoporous aluminosilicate molecular sieve （MASMS-1） stable in the high-temperature steam has been successfully synthesized from the assembly of diluted ZSM-5-type precursor with mesoporous MCM-41. The m...The ordered mesoporous aluminosilicate molecular sieve （MASMS-1） stable in the high-temperature steam has been successfully synthesized from the assembly of diluted ZSM-5-type precursor with mesoporous MCM-41. The material was characterized by XRD, N2 adsorption-desorption, FE-SEM, TEM, FT-IR spectroscopy and 27A1 MAS NMR techniques. This mesoporous material shows high stability in the high-temperature steam [H2O （φ=20%） in N2 at 800 ℃ for 4 h], which might be ascribed to the synergistic effect of both thick walls containing zeolite-like five-membered ring subunits and highly condensed surface silanol groups.展开更多
Following hydrothermal synthesis process, MCM-41 was synthesized by using cetyltriethylammonium bromide as templating agent. The experimental results showed that MCM-41 with pore diameter in the range of 4-7 nm can be...Following hydrothermal synthesis process, MCM-41 was synthesized by using cetyltriethylammonium bromide as templating agent. The experimental results showed that MCM-41 with pore diameter in the range of 4-7 nm can be obtained by adjusting nsurf/nsi. It was proved that cetyltriethylammonium bromide is an effective templating agent for increasing pore diameter of molecular sieve MCM-41.展开更多
The mesoporous molecular sieves MCM-41 were prepared using room tempera-ture ionic liquid （RTIL） synthesized in laboratory and cethytrimethylammonium bromide （CTAB） as compound templates for the first time. They w...The mesoporous molecular sieves MCM-41 were prepared using room tempera-ture ionic liquid （RTIL） synthesized in laboratory and cethytrimethylammonium bromide （CTAB） as compound templates for the first time. They were prepared under low aging temperature and short aging time. Via characterizing by XRD and nitrogen adsorption instrument, MCM-41 synthesized by this new method exhibited good crystal structure and narrow pore distribution. The following pre-paratory conditions was optimal： the molar ratio of RTIL to CTAB was 1.0∶1.0, aging at 80 ℃, for 40 h and calcined at 540 ℃. It is found that the acidified MCM-41 improves its activity as catalyst over the unmodified ones.展开更多
采用水热合成法,以二正丙胺(DPA)和二异丙胺(DIPA)混合物为模板剂合成SAPO-11分子筛,考察了模板剂用量和混合模板剂中DPA和DIPA配比对所得产物的影响,并通过XRD、N2吸附、NH3-TPD和29Si MAS NMR等手段对样品进行了表征。结果表明,改变...采用水热合成法,以二正丙胺(DPA)和二异丙胺(DIPA)混合物为模板剂合成SAPO-11分子筛,考察了模板剂用量和混合模板剂中DPA和DIPA配比对所得产物的影响,并通过XRD、N2吸附、NH3-TPD和29Si MAS NMR等手段对样品进行了表征。结果表明,改变模板剂用量和配比不仅可以调节SAPO-11结晶度,还会改变Si在分子筛骨架上的分布,从而调节SAPO-11的酸性。当模板剂用量比为1.5,模板剂中DPA的质量分数为66%时,样品的Si区面积最小,Si(nAl)(0<n<4)结构最多。因此,分子筛酸性和对正十四烷异构活性也最高。展开更多
文摘Pure Mesoporous TiO2 molecular sieves (Ti-TMS) were synthesized with different templates for the first time and the templates can be successfully removed by refluxing the samples in the EtOH/H2O/KOH solution. The XRD pattern and TEM confirm that the uniformity and stability of Ti-TMS2 synthesized with dodecylamine as template is obviously inferior to that of Ti-TMS1 prepared with dodecylphosphate and hexadecylphosphate as templates. Furthermore, after the templates were removed, the mesostructure of Ti-TMS1 was preserved to a great degree than that of Ti-TMS2.
基金Project supported by Key Program of National Natural Science Foundation of China （Nos. 20433030, 90610002）, the National High-Tech Research and Development Program of China （No. 2006AA03Z328）, and the Natural Science Foundation of Zhejiang Province （No. Z406142）.
文摘The ordered mesoporous aluminosilicate molecular sieve （MASMS-1） stable in the high-temperature steam has been successfully synthesized from the assembly of diluted ZSM-5-type precursor with mesoporous MCM-41. The material was characterized by XRD, N2 adsorption-desorption, FE-SEM, TEM, FT-IR spectroscopy and 27A1 MAS NMR techniques. This mesoporous material shows high stability in the high-temperature steam [H2O （φ=20%） in N2 at 800 ℃ for 4 h], which might be ascribed to the synergistic effect of both thick walls containing zeolite-like five-membered ring subunits and highly condensed surface silanol groups.
文摘Following hydrothermal synthesis process, MCM-41 was synthesized by using cetyltriethylammonium bromide as templating agent. The experimental results showed that MCM-41 with pore diameter in the range of 4-7 nm can be obtained by adjusting nsurf/nsi. It was proved that cetyltriethylammonium bromide is an effective templating agent for increasing pore diameter of molecular sieve MCM-41.
基金Funded by Zhengzhou Natural Science Foundation (No. 064SJZJ23115)Key Laboratory Catalysis and Materials Science of Southcentral Universityfor Nationalities Foundation
文摘The mesoporous molecular sieves MCM-41 were prepared using room tempera-ture ionic liquid （RTIL） synthesized in laboratory and cethytrimethylammonium bromide （CTAB） as compound templates for the first time. They were prepared under low aging temperature and short aging time. Via characterizing by XRD and nitrogen adsorption instrument, MCM-41 synthesized by this new method exhibited good crystal structure and narrow pore distribution. The following pre-paratory conditions was optimal： the molar ratio of RTIL to CTAB was 1.0∶1.0, aging at 80 ℃, for 40 h and calcined at 540 ℃. It is found that the acidified MCM-41 improves its activity as catalyst over the unmodified ones.
文摘采用水热合成法,以二正丙胺(DPA)和二异丙胺(DIPA)混合物为模板剂合成SAPO-11分子筛,考察了模板剂用量和混合模板剂中DPA和DIPA配比对所得产物的影响,并通过XRD、N2吸附、NH3-TPD和29Si MAS NMR等手段对样品进行了表征。结果表明,改变模板剂用量和配比不仅可以调节SAPO-11结晶度,还会改变Si在分子筛骨架上的分布,从而调节SAPO-11的酸性。当模板剂用量比为1.5,模板剂中DPA的质量分数为66%时,样品的Si区面积最小,Si(nAl)(0<n<4)结构最多。因此,分子筛酸性和对正十四烷异构活性也最高。
