杂多酸在活性炭上的固载化 Ⅱ．几种国产活性炭的表面性质对杂多酸吸附作用的影响

本文研究了四种具有Ｋｅｇｇｉｎ结构的杂多酸在五种国产改性活性炭载体上的吸附作用．实验结果表明，不同的杂多酸在活性炭上的吸附量是不同的，并且不同的活性炭对杂多酸的吸附等温线和吸附能力也不同．活性炭的表面化学性质显著地影响杂多酸在其上的吸附。     

杂多酸在活性炭上的固载化Ⅱ.几种国产活性炭的表面性质对…

本文研究了四种具有Ｋｅｇｇｉｎ结构的杂多酸在五种国产改性活性炭载体上的吸附作用。实验结果表明，不同的杂多酸在活性炭上的吸附量不同的，并且不同的活性炭对杂多酸的吸附等温线和吸附能力出不同。活性炭的表面化学性质显著地影响杂多酸在其上吸附。     

杂多酸在活性炭上的固载化Ⅲ．活性炭在酸性介质中对钨硅杂多酸（SiW_（12））的吸附

在氢离子浓度均为３ｍｏｌ／Ｌ的硫酸，盐酸，磷酸，醋酸水溶液中和冰醋酸中研究了具有Ｋｅｇｇｉｎ结构的硅钨杂多酸（ＳｉＷ＿（１２））在不同来源活性炭上的吸附作用。各活性炭对ＳｉＷ＿（１２）吸附等温线的形式是不相同的，吸附剂载体的微孔结构以及杂多酸的溶剂化起着重要的作用。并且在无机酸介质中，杂多酸的吸附量比在水溶液中成规律性地增加，且与酸强度成正比关系。在有机酸介质中，吸附作用比较复杂。根据所得结果，提出了在酸性介质中杂多酸在活性炭表面的吸附模型。     

活性炭负载杂多酸催化剂的研究进展

介绍了以活性炭为载体的负载型杂多酸催化剂的研究进展,包括制备方法、影响负载量的因素、负载催化剂的性质、吸附模型和脱附作用。总结了杂多酸在活性炭上的吸附形态研究以及杂多酸与活性炭表面含氧基团的化学键合作用的研究成果,展望了该催化剂未来的研究方向。     

活性炭表面固载十二硅钨酸的表征

活性炭表面固载十二硅钨酸的表征王新平，叶兴凯，吴越（中国科学院长春应用化学研究所，长春１３００２２）关键词硅钨酸，杂多酸，活性炭，负载型催化剂，表征由于杂多酸的优异催化性能，近年来其固载化的研究深受人们的关注［１］．活性炭是固载杂多酸较好的载体之一［...     

杂多酸的固载化─关于制备负载型酸催化剂的一般原理

杂多酸同时具有酸和氧化－还原的催化特性，有着很广泛的应用前景．这类化合物在一系列精细合成中取代硫酸作为催化剂以满足环保的要求，显示出了很大的潜力．杂多酸固载化后，不仅能在液相氧化和酸催化反应中把催化剂从反应介质中很方便地分离出来，而且还为这类均相催化反应的多相化，甚至利用催化蒸馏新工艺等创造了应有的条件，可以使生产工艺大大简化，获得更广泛的应用．本文以很好表征过的多种孔性材料，包括氧化物，如Ａｌ_２Ｏ_３、ＳｉＯ_２、ＴｉＯ_２、硅藻土、膨润土和来源不同的活性炭为载体，考察了负载杂多酸催化剂的催化活性．在大量前期工作的基础上，通过总结载体对固载杂多酸催化活性的影响等，探讨载体的内在性质在杂多酸固载、吸附和催化反应中的作用本质，为由吸附法制备各种负载型固体酸催化剂在液相中的应用提供可资参考的模型．     

杂多酸在活性炭上的固载化：III.活性炭在酸性介质中对钨硅杂多酸（SiW12…

在氢离子浓度均为３ｍｏｌ／Ｌ的硫酸，盐酸，磷酸，醋酸水溶液中和冰醋酸中研究了具有Ｋｅｇｇｉｎ结构的硅钨杂多酸（ＳｉＷ１２）在不同来源活性炭上的吸附作用，各活性炭对ＳｉＷ１２吸附等温线的形式是不相同的，吸附剂载体的微孔结构以及杂多酸的溶剂化起着重要的，工且在无机酸介质中，杂多酸的吸附量比在水溶液中成规律地增加，且与酸强度正比关系，在有机酸介质中，吸附作用比较复杂，根据所得结果，提出了在酸性中杂多酸在     

活性炭负载磷钨酸催化剂的表征及其催化性能

研究了活性炭负载磷钨酸催化剂的表征及在丁基多苷合成中的催化性能.活性炭负载磷钨酸催化剂采用浸渍法制备,并用FT-IR光谱、XRD光谱、SEM等手段进行了表征.结果表明,磷钨酸负载到活性炭后保持了原有的Keggin结构,它在载体上的吸附过程可以分为单分子吸附、多分子吸附和体相堆积三个阶段.在丁基多苷合成反应中,催化剂负载量、磷钨酸溶脱量、葡萄糖转化率之间有较复杂的关系.杂多酸溶脱量随负载量增大而增大,转化率与杂多酸溶脱量之间没有直接联系.催化剂负载量在5%到60%之间变化时,控制催化活性的主要因素分别是催化剂酸量、比表面积、游离的杂多酸量.最佳负载量为20%.     

酸处理活性炭催化水合肼还原硝基苯(英文)

以水合肼为还原剂,采用硝酸、盐酸、硫酸及氮气或氢气氛处理的活性炭为催化剂,考察了其催化硝基苯还原反应性能.结果表明,经化学处理后,活性炭表面形成了各种含氧官能团,它们可引发水合肼分解,并影响硝基苯的吸附.活性炭表面形成的含氧官能团越多,其催化硝基苯还原速率越快.其中经盐酸处理的活性炭表面形成的含氧官能团最多,因而表现出最高的硝基苯还原活性.     

聚丙烯腈活性炭纤维对硫化氢的常温吸附

聚丙烯腈活性炭纤维（PAN-ACF）对硫化氢（H2S）有比其他活性炭材料更强的吸附能力。H2S在PAN-ACF上的吸附是一个兼具物理吸附特征的化学吸附、催化转化过程。其化学吸附位主要位于微孔表面。吸附过程为：H2S分子首先被物理吸附进入微孔空间,而后在微孔表面的化学吸附位上进行包含电子转移的化学吸附、催化氧化,在炭表面产生相对稳定的化学结构。     

Tungsten/Alumina Catalysts: Effect of H3PW12O40 Countercation on Surface Properties and Hydrodesulfurization Activity

H₃PW₁₂O₄₀ heteropoly acid (HPW₁₂) and its Co, Fe, Ni salts supported on alumina have been used to model hydrodesulfurization catalysts of different activity. All catalysts revealed a promoting effect of the countercation in thiophene hydrodesulfurization, that of the nickel cation being the highest. The catalysts were characterized by measurements of surface area, HDS activity, TPR, FTIR, and DR spectra. IR spectra confirmed an effect of the countercation on the phase composition of the supported heteropoly compounds. 12-Tungstoaluminate heteropoly anions and coordinately unsaturated anions of HPW₁₂ were detected in the IR spectra of the catalysts. The hydrotreating activity of the catalysts was proportional to the amount of hydrogen consumed in the range 20–500°C during TPR.     

Studies on the Interaction of 12-Tungstophosphoric Acid and Diethylene Glycol

The homogeneous system of 12-tungstophosphoric acid and diethylene glycol was studied using IR and NMR spectra. It was found that the protons in 12-tungstophosphoric acid formed proton oxonium ions with the hydroxyl oxygen in diethylene glycol by hydrogen-bonds, and the formed proton oxonium ions could react with the terminal oxygens of heteropoly anions. The dehydration-cyclization mechanism of diethylene glycol in the presence of heteropoly acid was also proposed.     

SiW12／Al2O3为前身态的加氢脱氮催化剂研究

本文制备了担载在Ａｌ２Ｏ３上的十二钨硅酸为前身态的加氢脱氮催化剂，用ＸＲＤ，ＩＲ表征了催化剂的表面结构，结果表明，在Ａｌ２Ｏ载体上，ＳｉＷ１２仍保持着其Ｋｅｇｇｉｎ结构并以高度分散状态存在。     

Voltammetric and FT-IR studies of modified activated carbon systems with phenol, 4-chlorophenol or 1,4-benzoquinone adsorbed from aqueous electrolyte solutions

Cyclic voltammetric and spectral FT-IR studies of the influence of surface chemistry on the adsorption and electrochemical behaviour of powdered activated carbon electrodes (PACE) in the presence of phenol, 4-chlorophenol and 1,4-benzoquinone were carried out. The variety of surface chemical properties was achieved through modification of the carbon samples by heat treatment under vacuum and in an oxygen–ammonia atmosphere as well as by oxidation with conc. nitric acid. Adsorption processes were carried out from aqueous solutions (in air and an oxygen-free atmosphere) in the presence acidic, neutral or basic electrolytes. Some electrochemical parameters of electrode systems with adsorbed organics were estimated and correlated with the adsorption ability of carbon materials. The changes in FT-IR spectra of the carbons caused by adsorption and/or coupling organic molecules are presented and discussed.     

Removal of phenols from water and petroleum industry refinery effluents by activated carbon obtained from coconut coir pith

Coir pith obtained from the coir industry as waste biomass was used to prepare activated carbon by chemical activation using phosphoric acid (H₃PO₄). The influences of activation temperature and lasting time of activation on specific surface areas (SSA) of the activated carbons were observed. Physical characteristics of the activated carbon were investigated using X-ray diffraction (XRD), infra-red spectroscopy (IR), surface area analyzer, scanning electron microscopy (SEM), thermal analysis and potentiometric titration. The feasibility of using activated carbon for the removal of phenol (P), p-chlorophenol (PCP) and p-nitrophenol (PNP) from water and petroleum refinery industry effluents was investigated. The effects of contact time, adsorbent dose, ionic strength and initial concentration on the adsorption of phenols onto the activated carbon were investigated. The optimum pH for the maximum removal of phenols was 6.0. The equilibrium adsorption data of phenols were correlated to Langmuir and Freundlich isotherm models, the latter being the best fit of the experimental data. Dynamics of the sorption process and mass transfer were investigated using McKay and Urano-Tachikawa models. Adsorption kinetic data fits the Urano-Tachikawa kinetic model. The utility of the adsorbent was tested by using petroleum refinery industry effluent. The adsorbed phenols can be recovered by treatment with 0.1 M NaOH solution.     

钨基加氢脱氮催化剂载体与活性前身物的作用

为研究载体表面化学性质和钨前物结构对钨基加氢脱氮催化剂活性的影响，以ＩＲ，ＸＲＤ，程序升温硫化方法，研究了十二磷钨酸和偏钨酸铵两种不同结构的前身物在Ａｌ２Ｏ３的活性表面的分散状态。     

Quantitative SNIFTIRS studies of (bi)sulfate adsorption at the Pt(111) electrode surface

Subtractively normalized interfacial Fourier transform infrared reflection spectroscopy (SNIFTIRS) was applied to study (bi)sulfate adsorption on a Pt(111) surface in solutions of variable pH while maintaining a constant total bisulfate/sulfate ((bi)sulfate) concentration without the addition of an inert supporting electrolyte. The spectra were recorded for both the p- and s-polarizations of the IR radiation in order to differentiate between the IR bands of the (bi)sulfate species adsorbed on the electrode surface from those species located in the thin layer of electrolyte. The spectra recorded with p-polarized light consist of the IR bands from both the species adsorbed at the electrode surface and those present in the thin layer of electrolyte between the electrode surface and ZnSe window whereas the s-polarized spectra contain only the IR bands from the species located in the thin layer of electrolyte. A new procedure was developed to calculate the angle of incidence and thickness of the electrolyte between the Pt(111) electrode surface and the ZnSe IR transparent window. By combining these values with the knowledge of the optical constants for Pt, H(2)O and ZnSe, the mean square electric field strength (MSEFS) at the Pt(111) electrode surface and for thin layer of solution were accurately calculated. The spectra recorded using s-polarization were multiplied by the ratio of the average MSEFS for p- and s-polarizations and subtracted from the spectra recorded using p-polarization in order to remove the IR bands that arise from the species present within the thin layer cavity. In this manner, the resulting IR spectra contain only the IR bands for the anions adsorbed on the Pt(111) electrode surface. The spectra of adsorbed anions show little change with respect to the pH ranging from 1 to 5.6. This behavior indicates that the same species is predominantly adsorbed on the metal surface for this broad range of pH values and the results suggest that sulfate is the most likely candidate for this adsorbate.     

Study on radiation-induced polymerization of vinyl monomers adsorbed on inorganic substances. II. Radiation-induced polymerization of methyl methacrylate adsorbed on several inorganic substances

The radiation-induced polymerization of methyl methacrylate (MMA) absorbed on such inorganic substances as silica gel, white carbon, silicic acid anhydride, zeolite, and activated alumina was carried out to compare with the case of styrene. The rate of radiation-induced polymerization adsorbed on inorganic substances was high compared with that of radiation-induced bulk state polymerization, as was the case with styrene. Inorganic substrates which contain aluminum as a component element are more likely to be grafted than those which consist of SiO₂ alone, as with styrene. The molecular weight distribution of unextractable polymer and extractable polymer differs, depending on the type of inorganic substance. Experiments by a preirradiation method were carried out in case of silica gel, white carbon, and silicic acid anhydride. GPC spectra of the polymer obtained were different from those of polymer formed by the simultaneous irradiation method. It appears that all the unextractable polymer is grafted to the inorganic surface with chemical bond.     

硅藻土负载H6PMo9V2Nb1O40催化剂上乙烷氧化制乙酸和乙醛的反应性能

采用浸渍法制备了硅藻土负载的杂多化合物催化剂PMo9V2Nb1/K,利用TPR、IR、TPD和微反技术研究了催化剂的表面酸性、乙烷化学吸附和氧化反应性能。结果表明,含铌的PMo9V2Nb1/K催化剂仍保持着Keggin形杂多酸的化学构造,晶格氧的活泼性明显提高,B酸强度和酸量均有所降低;乙烷分子主要通过H原子吸附在Lewis碱位V—O—Mo和Nb—O—Mo的桥氧上,吸附在Nb—O—Mo桥氧上的乙烷易发生解离吸附,并与邻近的表面氧发生反应生成乙酸或乙醛;在240 ℃,0.4 MPa和2 000 h-1下,乙烷的摩尔转化率为22.5%,产物乙酸和乙醛的总选择性达90.8%。