聚(2,5-二氧基苯胺)膜修饰电极的电化学及催化性质

二甲氧基苯胺;电沉积;氧化;化学修饰电极;聚(2;5-二氧基苯胺)膜修饰电极的电化学及催化性质     

微波法研制CaO/NaY强碱性沸石催化新材料

 通过微波辐射可以将CaO分散在NaY沸石上而形成强碱位,高温活化后其碱强度可达到H－＝27．0,成为具有超强碱性的催化新材料．CaO／NaY具有耐水冲刷性,能克服通常负载型固体碱在水中易流失的弱点．     

Kinetics of epoxidation of propylene over TS-1 in isopropanol

The intrinsic kinetics of propylene epoxidation with H₂O₂ catalyzed by TS-1 in isopropanol/water system was investigated. A kinetic model was established in accordance with the proposed reaction mechanism. Based on the experimental data, parameters were estimated, indicating that the Eley-Rideal model fits precisely the experimental data. This revised version was published online in June 2006 with corrections to the Cover Date.     

Selective Deposition of Biocompatible Sol-Gel Materials

Sulphated zirconias with various atomic S/Zr ratios were prepared by sol–gel method. The acidity of these solids has been studied through qualitative and quantitative XPS studies, surface potential measurements and isopropanol dehydration reaction. The Correlation between corresponding results show that when zirconia is doped by sulfate groups the surface becomes more acidic in term of Lewis acidity and that the oxygen species in the sample exist in many types, which one is related to solid acidity. This type of oxygen species, probably in the hydroxyl groups, is other than the oxygen species of zirconia network and the oxygen sulphate groups. Consequently, acidity of sulphated zirconia is mainly due to a strong Lewis nature of the surface, which can give a Brönsted acidity by water or reactant chemisorptions     

Preparation of N-doped TiO<Subscript>2</Subscript> photocatalyst by atmospheric pressure plasma process for VOCs decomposition under UV and visible light sources

The nitrogen doped (N-doped) titanium dioxide (TiO₂) photocatalyst was prepared by the atmospheric-pressure plasma-enhanced nanoparticles synthesis (APPENS) process operated under normal temperature, i.e. the dielectric barrier discharge plasma process. The N₂ carrier gas is dissociated in the AC powered nonthermal plasma environment and subsequently doped into the TiO₂ photocatalyst that was capable of being induced by visible light sources. The APPENS process for producing N-doped TiO₂ showed a higher film deposition rate in the range of 60–94 nm/min while consuming less power (<100 W) as compared to other plasma processes reported in literatures. And the photocatalytic activity of the N-doped TiO₂ photocatalyst was higher than the commercial ST01 and P25 photocatalysts in terms of toluene removals in a continuous flow reactor. The XPS measurement data indicated that the active N doping states exhibited N 1s binding energies were centered at 400 and 402 eV instead of the TiN binding at 396 eV commonly observed in the literature. The light absorption in the visible light range for N-doped TiO₂ was also confirmed by a clear red shift of the UV-visible spectra.     

改进水热法合成SAPO-11及其酸性和异构化活性

在含异丙醇的体系中,采用程序升温水热法合成了SAPO-11分子筛,并通过X射线衍射、扫描电镜、低温氮物理吸附、氨程序升温脱附、吡啶吸附红外光谱和29Si固体核磁共振等手段进行了表征.结果表明,与常规水热合成法相比,该方法合成的SAPO-11结晶度高,晶粒小,微孔分布集中,酸性强,同时还具有较大的比表面积和微孔孔容.以该分子筛制备的Pt/SAPO-11催化剂在正十四烷临氢异构反应中表现出较高的催化活性和异构选择性.     

间歇式水热合成制备丝光沸石膜及其异丙醇脱水应用

采用市售廉价大孔α-Al₂O₃管作为基质材料,通过热浸渍法在管外表面涂敷晶种,随后在无模板剂体系下,利用新型的间歇式水热合成法制备丝光沸石膜。对比了传统加热和间歇式加热对丝光沸石膜形貌、结构及渗透蒸发异丙醇脱水分离性能的差异。考察了合成液中Na₂O/SiO₂、SiO₂/Al₂O₃和NaF/SiO₂物质的量之比在间歇式水热合成下对丝光沸石膜的影响。研究结果表明,当合成液中Na₂O/SiO₂、SiO₂/Al₂O₃和NaF/SiO₂物质的量之比分别为0.24、16.7和0.25时,制备的丝光沸石膜渗透蒸发异丙醇脱水分离性能最佳,在75℃下,对异丙醇/水(9:1,w/w)的渗透通量达5.60 kg·m^-2·h^-1,水对异丙醇的分离因数大于10 00...