Rational design of organic structure-directing agents(OSDAs)is always regarded as a promising strategy to produce ZSM-48 with diverse configurations.However,to date,only OSDAs with alkyl and alkenyl groups have been e...Rational design of organic structure-directing agents(OSDAs)is always regarded as a promising strategy to produce ZSM-48 with diverse configurations.However,to date,only OSDAs with alkyl and alkenyl groups have been employed to produce ^(*)MRE zeolites with different structures.Aromatic heterocyclic groups were rarely considered for the synthesis of ZSM-48 with a unique nanostructure.In this work,a triazine-based bolaform quaternary ammonium bifunctional template was designed for the first time to fabricate nanorod stacked hierarchical ZSM-48(NSH-ZSM-48).Nanorod-stacked ZSM-48 with different SiO_(2)/Al_(2)O_(3) ratios ranging from 100 to 500 was obtained via a conventional procedure,using the synthesized s-triazine based OSDA,and a reasonable formation mechanism was proposed based on geometrical matching.We also demonstrated that the ZSM-48 nanorods piled up to form an ordered bird’s nest-like hollow sphere configuration.The synthesized NSH-ZSM-48 possesses abundant mesopores and a high surface area,attributed to the SDA’s mesopore-forming and nanonrod’s stacking abilities.In contrast to conventional materials,1 wt%Pd/NSH-ZSM-48 experiences a dramatic increase in the conversion(3.59%)and selectivity(95.7%)of a cyclohexanol/cyclohexanone mixture in the selective oxidation of cyclohexane,which are higher than those for silicalite-1 and SBA-15 with the same loading(2.11%/66.1%and 1.76%/68.5%,respectively).展开更多
以α,ω-二溴代烷、丁基咪唑和三丁基膦为原料经过二步反应合成了3种Bola型非对称阳离子表面活性剂。中间体1-（12-溴十二烷基）-3-丁基咪唑溴盐的较佳合成工艺条件为：n（丁基咪唑）∶n（1,12-二溴十二烷）∶n（四丁基碘化铵）=1∶1.5...以α,ω-二溴代烷、丁基咪唑和三丁基膦为原料经过二步反应合成了3种Bola型非对称阳离子表面活性剂。中间体1-（12-溴十二烷基）-3-丁基咪唑溴盐的较佳合成工艺条件为：n（丁基咪唑）∶n（1,12-二溴十二烷）∶n（四丁基碘化铵）=1∶1.5∶0.005,异丙醇作溶剂,反应温度65℃,反应时间6 h;Bola型表面活性剂的合成工艺条件为：n（1-（12-溴十二烷基）-3-丁基咪唑溴盐）∶n（三丁基膦）=1.05∶1,微波辅助反应,反应温度80℃,反应时间12 h。所合成的Bola型表面活性剂表现出了优良的表面活性,30℃时cmc在5.7×10^-3～8.7×10^-2mol·L^-1之间、γcmc在30～36 m N·m^-1之间;随着碳链长度的增长,其cmc,γ_cmc及分子最小横截面积（A_min）逐渐减小,饱和吸附量（Γ_max）和吸附效率（pc_20）逐渐增大。展开更多
A bolaform amphiphile(BP-15) bearing biphenyl group and long spacers of alkyl chains was synthesized. In-situ AFM studies indicate that the amphiphile can form two kinds of surface aggregates with different morphologi...A bolaform amphiphile(BP-15) bearing biphenyl group and long spacers of alkyl chains was synthesized. In-situ AFM studies indicate that the amphiphile can form two kinds of surface aggregates with different morphologies depending on solution concentration: short-range ordered cylindrical surface micelles at the lower concentration and flat domains at the higher concentration. These results agree well with the two critical micelle concentrations in bulk solution as determined by the concentration-dependent conductivity.展开更多
以八铵基头bola型表面活性剂为模板剂,采用水热法在碱性条件下以100Si O2∶4Na Al O2∶4SDA∶33Na OH∶6000H2O配比合成beta中微双孔分子筛。合成的beta分子筛用扫描电镜、透射电镜、X射线衍射、氮气吸脱附、魔角核磁共振等技术对其进...以八铵基头bola型表面活性剂为模板剂,采用水热法在碱性条件下以100Si O2∶4Na Al O2∶4SDA∶33Na OH∶6000H2O配比合成beta中微双孔分子筛。合成的beta分子筛用扫描电镜、透射电镜、X射线衍射、氮气吸脱附、魔角核磁共振等技术对其进行表征。结果表明样品中孔孔壁中具有结晶性硅铝酸盐的微孔结构。醇醛缩合与傅克烷基化催化反应及甲苯气体吸附试验表明,相比于传统的beta分子筛,在涉及大分子的催化反应和大分子有机气体的吸附应用中,所合成的中微双孔分子筛具有明显的优势。展开更多
基金financially supported by the National Natural Science Foundation of China(21776311 and 22102215)Taishan Scholar Foundation(tspd20210308)+3 种基金the“111”Program of National College Disciplinary Innovation(B13031)Shandong Provincial Natural Science Foundation,China(ZR2019MB045 and ZR2019MB022)the National Key Technologies R&D Program of China,the Key Projects of Intergovernmental International Innovation Cooperation(2018YFE0118200)the Key Research and Development Project of Shandong province(2019JZZY010506).
文摘Rational design of organic structure-directing agents(OSDAs)is always regarded as a promising strategy to produce ZSM-48 with diverse configurations.However,to date,only OSDAs with alkyl and alkenyl groups have been employed to produce ^(*)MRE zeolites with different structures.Aromatic heterocyclic groups were rarely considered for the synthesis of ZSM-48 with a unique nanostructure.In this work,a triazine-based bolaform quaternary ammonium bifunctional template was designed for the first time to fabricate nanorod stacked hierarchical ZSM-48(NSH-ZSM-48).Nanorod-stacked ZSM-48 with different SiO_(2)/Al_(2)O_(3) ratios ranging from 100 to 500 was obtained via a conventional procedure,using the synthesized s-triazine based OSDA,and a reasonable formation mechanism was proposed based on geometrical matching.We also demonstrated that the ZSM-48 nanorods piled up to form an ordered bird’s nest-like hollow sphere configuration.The synthesized NSH-ZSM-48 possesses abundant mesopores and a high surface area,attributed to the SDA’s mesopore-forming and nanonrod’s stacking abilities.In contrast to conventional materials,1 wt%Pd/NSH-ZSM-48 experiences a dramatic increase in the conversion(3.59%)and selectivity(95.7%)of a cyclohexanol/cyclohexanone mixture in the selective oxidation of cyclohexane,which are higher than those for silicalite-1 and SBA-15 with the same loading(2.11%/66.1%and 1.76%/68.5%,respectively).
文摘以α,ω-二溴代烷、丁基咪唑和三丁基膦为原料经过二步反应合成了3种Bola型非对称阳离子表面活性剂。中间体1-（12-溴十二烷基）-3-丁基咪唑溴盐的较佳合成工艺条件为：n（丁基咪唑）∶n（1,12-二溴十二烷）∶n（四丁基碘化铵）=1∶1.5∶0.005,异丙醇作溶剂,反应温度65℃,反应时间6 h;Bola型表面活性剂的合成工艺条件为：n（1-（12-溴十二烷基）-3-丁基咪唑溴盐）∶n（三丁基膦）=1.05∶1,微波辅助反应,反应温度80℃,反应时间12 h。所合成的Bola型表面活性剂表现出了优良的表面活性,30℃时cmc在5.7×10^-3～8.7×10^-2mol·L^-1之间、γcmc在30～36 m N·m^-1之间;随着碳链长度的增长,其cmc,γ_cmc及分子最小横截面积（A_min）逐渐减小,饱和吸附量（Γ_max）和吸附效率（pc_20）逐渐增大。
文摘A bolaform amphiphile(BP-15) bearing biphenyl group and long spacers of alkyl chains was synthesized. In-situ AFM studies indicate that the amphiphile can form two kinds of surface aggregates with different morphologies depending on solution concentration: short-range ordered cylindrical surface micelles at the lower concentration and flat domains at the higher concentration. These results agree well with the two critical micelle concentrations in bulk solution as determined by the concentration-dependent conductivity.
文摘以八铵基头bola型表面活性剂为模板剂,采用水热法在碱性条件下以100Si O2∶4Na Al O2∶4SDA∶33Na OH∶6000H2O配比合成beta中微双孔分子筛。合成的beta分子筛用扫描电镜、透射电镜、X射线衍射、氮气吸脱附、魔角核磁共振等技术对其进行表征。结果表明样品中孔孔壁中具有结晶性硅铝酸盐的微孔结构。醇醛缩合与傅克烷基化催化反应及甲苯气体吸附试验表明,相比于传统的beta分子筛,在涉及大分子的催化反应和大分子有机气体的吸附应用中,所合成的中微双孔分子筛具有明显的优势。
