摘要
杂多化合物(POM)具有较强的酸性和氧化还原性，可作为双功能催化剂，是近年来无机化学及催化剂领域研究的热点之一。杂多化合物存在比表面积较小（<10m~2·g~(-1)）、热稳定性差等缺点，这大大限制了其在工业上的应用。因此，将杂多化合物负载于适当的载体上，以提高其比表面积和热稳定性，对于提高其催化活性及重复使用性具有重要的意义。
随着介孔分子筛的问世及研究的不断深入，人们开始探索将杂多化合物与这类比表面大、热稳定性高的介孔材料相复合，制备负载型杂多化合物分子筛催化剂。分子筛与杂多化合物复合，一方面可以利用杂多化合物的酸性及分子筛固有的酸性，提高催化剂的活性。另一方面可以利用分子筛特有的孔结构，提高催化剂的择形性，这些研究工作已取得了一定的成绩。目前报道的复合方法主要是浸渍-蒸发法，但这种方法通常会导致分子筛孔道的堵塞，降低催化剂的比表面积及孔容，而且杂多化合物与分子筛之间的作用力较弱，在反应体系中容易脱落，催化剂的活性及重复使用性较差。因此，设计新的复合方法，将杂多化合物组装复合到分子筛结构中，使其牢固的附着或结合于分子筛的孔腔内壁或骨架结构上，有效避免杂多化合物在催化反应过程中从分子筛的溶脱，可以有效提升催化剂的性能，将具有重要的学术价值及实际应用前景。
本文旨在从分子筛的形成机理入手，设计新的合成路线，一步法将杂多化合物组装于分子筛的孔道结构中，制备一系列杂多化合物-分子筛复合杂化材料。通过X射线衍射（XRD）、X射线荧光（XRF）、扫描电子显微镜（SEM）、高倍透射电子显微镜（HRTEM）、N2吸附-脱附（N2-sorption）等温线、红外吸收光谱（FT-IR）、拉曼光谱(Raman)、热重-差热分析（TG-DTA）等分析测试手段对合成的样品进行结构表征，研究不同合成条件对杂多化合物-分子筛杂化材料结构的影响，考察样品材料的催化性能。
论文的主要研究工作有：
1.用直接合成法，在初始pH为10的条件下室温晶化为24h下，成功合成了系列单缺位磷钨酸-MCM-41复合杂化材料。当MCM-41中单缺位磷钨酸（LPOM）含量不高于35wt%时，MCM-41结构和形貌基本不变。复合材料具有规则的六方介孔孔道结构，其比表面积及孔径远远大于浸渍负载法所得样品，例如25%LPOM/MCM-41的比表面积为743m~2·g~(-1)，孔径为2.9nm左右，远远高于浸渍负载型25%LPOM/MCM-41-IM的比表面积536m~2·g~(-1)和孔径2.3nm。另外，在分子筛结构中LPOM的热稳定性也得以提高，其最终分解温度由574oC提高到了596oC。该类杂化材料对酯化反应及模拟油品的氧化脱硫反应均具有很好的催化活性及重复使用性。如25%LPOM/MCM-41样品在实验优化的条件下，可使乙酸与正丁醇的酯化反应中正丁醇的转化率达到89.6%，对乙酸正丁酯的选择性为100%。在60oC下、80min内可使模拟油中的硫含量从500ppm降低到6.85ppm，相应的脱硫率为98.63%。催化剂重复使用4次后，催化活性降低不明显。
2.用直接合成法，成功合成了系列过渡金属取代磷钨酸-MCM-41杂化材料。当MCM-41中过渡金属取代磷钨酸（M_1-POM）含量高达25wt%时，MCM-41结构和形貌基本不变。复合材料具有规则的六方介孔孔道结构，其比表面积及孔径远远大于浸渍负载法所得样品，例如15%Ni-POM/MCM-41的比表面积为863m~2·g~(-1)，孔径为2.6nm左右，远远高于浸渍负载型15%Ni-POM/MCM-41-IM的比表面积674m~2·g~(-1)和孔径2.2nm。该类杂化材料对酯化反应具有很好的催化活性及重复使用性。如25%Ni-POM/MCM-41样品在实验优化的条件下，可使乙酸与正丁醇的酯化反应中正丁醇的转化率达到90.2%，对乙酸正丁酯的选择性为100%。然而，25%Cu-POM/MCM-41样品对模拟油的氧化脱硫反应催化活性不高，在60oC下、80min内仅使模拟油中的硫含量从500ppm降低到45.16ppm，相应的脱硫率仅为90.91%。
3.用直接合成法，在晶化温度为室温，晶化时间为24h下，成功合成了系列磷钨酸(HPW)-HMS复合杂化材料。复合材料具有有序的指纹状介孔孔道结构，其比表面积在1011-746m~2·g~(-1)范围内，孔径在2.2nm左右，远远大于浸渍负载法所得样品30%HPW-HMS-IM的比表面积（546m~2·g~(-1)）和孔径（1.9nm）。该类杂化材料对酯化反应及模拟油品的氧化脱硫反应均具有很好的催化活性及重复使用性。如30%HPW-HMS-DS样品在实验优化的条件下，可使乙酸与正丁醇的酯化反应中正丁醇的转化率达到86.9%，对乙酸正丁酯的选择性为100%。20%HPW-HMS-DS样品在60oC、60min内可使脱硫率达到98.51%。
4.用直接合成法，在晶化时间为36h，晶化温度为40℃下，成功合成了系列单缺位磷钨酸-HMS复合杂化材料。该材料具有有序的介孔孔道和较大的空腔结构，其比表面积在997-626m~2·g~(-1)范围内，孔径在3.8nm左右，该类杂化材料对酯化反应及模拟油品的氧化脱硫反应均具有很好的催化活性及重复使用性。如20%LPOM-HMS-DS样品在实验优化的条件下，可使乙酸与正丁醇的酯化反应中正丁醇的转化率达到88.3%，对乙酸正丁酯的选择性为100%。催化剂重复使用3次后，催化活性没有明显下降。20%LPOM-HMS-DS样品，在60oC下、80min内可使脱硫率达到98.67%。
5.本文分别探讨了催化剂对酯化反应及油品氧化脱硫反应的催化机理。认为酯化反应发生在MCM-41分子筛中单缺位磷钨酸表面的B酸位上。正丁醇首先吸附在LPOM的表面，形成了一个碳正离子。然后，乙酸进攻碳正离子形成一个不稳定中间体，不稳定中间体通过脱质子而生成乙酸丁酯和水。
6.探讨了杂化复合材料的形成机理，提出了直接法（或一步法）合成杂多化合物-分子筛杂化材料形成的静电作用“夹层机理”。其核心是通过表面活性剂阳离子和杂多化合物阴离子之间的静电作用将杂多化合物引入到二氧化硅层与模板剂胶束之间的“夹层”界面中，最终将杂多化合物组装到分子筛的孔道内。
Polyoxometalate (POM) is one of the most promising catalysts used asthe dual function catalyst due to its strong acidity and appropriate redoxproperty. However, POM suffers from some shortcomings, such as the smallsurface area (1-10m2·g-1), low thermal stability and the difficulties inseparation and recovery. These drawbacks greatly limit their applications incatalytic processes. In order to improve its catalytic performance, the POMwas dispersed into the carriers with high surface area. Some groups have beendevoting into synthesizing the POM catalysts combined with the mesoporousmaterials due to their large surface areas and high thermal stabilities. It wasfound that incorporation of POM into molecular sieves not only improved thesurface acidity of molecular sieves, but also greatly increased the selectivity ofmolecular sieves in catalytic reactions.
At present, the incorporation of POM into the mesoporous materials wasprimarily through the impregnation methods followed by evaporation of thesolvent. However, the POM in these samples can significantly reduce thesurface area of the mesoporous materials through blocking the pores, and thePOM can also diffuse into the polar solvents, resulting in the great decrease in catalytic activity. Therefore, it is necessary to find a new method which canstrengthen the interaction of mesoporous molecular sieves andpolyoxometalates, reduce the loss of polyoxometalates in the catalytic reaction,and improve the catalytic performance.
In this paper, we synthesized the mesoporous molecular sievesincorporated with polyoxometalates via a novel direct method. All of thesamples were characterized by the XRD, XRF, SEM, HRTEM, N2-sorption,FT-IR, Raman and TG-DTA techniques, followed by the catalytic tests. Thedetails are described as followings:
1. The ordered mesoporous MCM-41materials incorporated withlacunary polyoxometalate (LPOM) were prepared via an original directsynthesis method at room temperature with24h and under the initial pH valueof10. When the LPOM content is less than35wt%in LPOM/MCM-41samples, the structure and morphology of MCM-41do not changed. Inaddition, the materials contain ordered hexagonal mesoporous structure. Andthe LPOM/MCM-41catalysts possess larger surface areas, larger porediameter and larger pore volume than the impregnation samples. For example,the25%LPOM/MCM-41sample exhibits a specific surface area of743m2/gand a pore size of2.90nm, is much bigger than that of the25%LPOM/MCM-41-IM sample (536m2/g,2.32nm). In addition, the thermalstability of LPOM in the molecular sieve is also improved, and its finaldecomposition temperature increased from574oC to596oC. The hybridmaterials show good catalytic activities and reusability in both esterification and oxidation desulfurization of simulated oil. In particular, the25%LPOM-MCM-41sample exhibits an excellent catalytic performance.Under the optimized conditions, the conversion of n-butanol is89.7%, and theselectivity of butyl acetate is nearly100%. For the15%LPOM-MCM-41, thesulfur content can be efficiently decreased from500to7.53ppm at60oCwithin80min corresponding to98.51%sulfur removal. Moreover, sulfurremoval is slightly decreased after4runs.
2. Well-ordered mesoporous MCM-41with transition metal-modifiedpolyoxometalate M_1-POM (M_1-POM=[PW511O39M_1], M_1=Ni or Cu) hasbeen synthesized by the directed synthesis method. After incorporating of highM_1-POM content, the pore structure and spherical morphology of MCM-41are unchanged. The M_1-POM/MCM-41catalysts possess larger surface areas,larger pore diameter and larger pore volume than the impregnation samples.For example, the15%Ni-POM/MCM-41sample exhibits a specific surfacearea of863m2/g and a pore size of2.6nm, is much bigger than that of the25%LPOM/MCM-41-IM sample (546m2/g,2.2nm). The materials showgood catalytic activities and reusability in esterification of acetic acid andn-butanol. For the25%Ni-POM/MCM-41, the conversion of n-butanol is90.2%, and the selectivity of butyl acetate is nearly100%, under the optimizedconditions. However, the catalytic activity of M_1-POM/MCM-41in oxidativedesulfurization of model oil is not high. For the15%Co-POM/MCM-41,sulfur removal is only86.97%at60oC within80min.
3. Well-ordered hexagonal mesoporous silicate (HMS) materials with various contents of phosphotungstic acid (HPW) were synthesized via anoriginal direct synthesis method. The crystallization temperature is under theroom temperature and the crystallization time is24h. The samples showhomogeneous dispersion of the HPW molecules and have regularfingerprint-like mesopores and spherical morphology. Compared with theconventional wet impregnation method, the samples obtained by our methodhave better HPW dispersions，larger specific surface area and larger porevolume. The specific surface area of HPW-HMS-DS samples is in the range of1011-746m~2·g~(-1), and the pore diameter is about2.2nm. And the directsynthesized samples exhibit better catalytic activities than the impregnatedsamples in both esterification and oxidation desulfurization. Under theoptimized conditions, for the30%HPW-HMS-DS, the conversion ofn-butanol is86.9%, and the selectivity of butyl acetate is nearly100%. For the20%HPW-HMS-DS, the sulfur content can be efficiently decreased from500to7.53ppm at60oC within60min corresponding to98.51%sulfur removal.
4. The LPOM were successfully incorporated into the hexagonalmesoporous HMS matrix via the directed synthesis method. Thecrystallization temperature is40oC and the crystallization time is236h. TheLPOM-HMS-DS samples possess Compared with the worm-like porestructure of HMS reported previously. The samples prepared in the acidmedium show an order pore structure with many uniform size of cavitystructure (about50nm). In addition, the material has a high specific surfacearea and big pore diameter. The specific surface area of the samples is in the range of997-626m~2·g~(-1), and the pore diameter is about3.8nm. The materialsshow good catalytic activities in the esterification and oxidationdesulfurization. For the20%LPOM-HMS-DS sample, the conversion ofn-butanol is88.3%, the selectivity of butyl acetate is nearly100%, and thesulfur removal is98.67%at60oC within80min. In addition, the catalystshave the excellent reusability.
5. We investigated the catalyst mechanism for the esterification. Firstly,the alcohol is chemisorbed on the Br nsted acid sites to form the carboniumions. The surface reaction is the rate determining step. Then the acetic acidattacks these carbocations to form an unstable intermediate which generatesbutyl acetate and water by deprotonation.
6. We proposed an electrostatic effect “mechanism of sandwich” used inthe direct synthesis (or one step synthesis) of the hybrid materials ofpolyoxometalates and mesoporous molecular sieves. Its core is to introducepolyoxometalate into the sandwich interface between the silicon dioxide layerand the template micelles through the electrostatic interaction of the surfactantcation and polyoxometalate anion, and eventually assemble thepolyoxometalates into the pore canal of molecular sieves.
引文
[1] I. Kozhevnikov, K. Matveev. Homogeneous catalysts based on heteropoly acids (review)[J]. Appl.Catal.，1983，5：135-150
[2] Katsoulis D E，Pope M T．Reactions of heteropolyanions in non—polar solvents．part3．Activationof dioxygen by manganese(Ⅱ) Centres in polytungstates oxidation of hindered phenois[J]．J.Chem. Soc. Dalton Trans.,1989,8:1483-1489
[3] R.J.J.Jansen, H.M.Van Veldhuizen, H.Van Bekkum. Heteropoly anion on carbon：characterizationand use in2，3，6-trimethylphenol oxidation [J]. J. Mol. Catal. A：Chem.，1996,107：241-246
[4] K.M. Rao, R. Gobetto, A. Iannibello, A. Zecchina. Solid state NMR and IR studies ofphosphomolybdenum and phosphotungsten heteropoly acids supported on SiO2，γ-Al2O3，andSiO2-Al2O3[J]. J. Catal.，1989,119：512-516
[5] E. Rafiee, S. Rashidzadeh, A. Azad. Silica-supported heteropoly acids：Highly efficient catalystsfor synthesis of [alpha]-aminonitriles，using trimethylsilyl cyanide or potassium cyanide [J]. J.Mol. Catal. A：Chem.，2007,261：49-52
[6] B. Bai, J. Zhao, X. Feng. Preparation and characterization of supported photocatalysts：HPAs/TiO2/SiO2composite [J]. Mater. Lett.，2003,57：3914-3918
[7] S. Kumbar, G. Shanbhag, F. Lefebvre et al.. Heteropoly acid supported on titania as solid acidcatalyst in alkylation of p-cresol with tert-butanol [J]. J. Mol. Catal. A：Chem.，2006，256：324-334
[8] G. Yadav, V. Bokade. Novelties of heteropoly acid supported on clay：Etherification of phenethylalcohol with alkanols [J]. Appl. Catal. A：Gen.，1996，147：299-323
[9] M. Misono, N. Nojiri. Recent progress in catalytic technology in Japan[J]. Appl. Catal.641990,64：1-30
[10] I.V. Kozhevnikov. Catalysis by heteropoly acids and multicomponent polyoxometalates inliquid-phase reactions [J]. Chem. Rev.，1998，98：171-198
[11] M. Timofeeva，R. Maksimovskaya，E. Paukshtis et al.. Esterification of2，6-pyridinedicarboxylicacid with n-butanol catalyzed by heteropoly acid H3PW12O40or its Ce (III) salt [J]. J. Mol. Catal.A：Chem.，1995，102：73-77
[12] M.A. Schwegler，H. Van Bekkum，N. De Munck. Heteropolyacids as catalysts for the productionof phthalate diesters[J]. Appl. Catal.，1991，74：191-204
[13] Y. Izumi，K. Matsuo，K. Urabe. Efficient homogeneous acid catalysis of heteropoly acid and itscharacterization through ether cleavage reactions [J]. Journal of Molecular Catalysis，18(1983)299-314.
[14] I. Kozhevnikov，S. Kulikov，N. Chukaeva et al.. Syntheses of vitamins E and K1catalyzed byheteropoly acids[J]. React. Kinet. Catal. Lett.，1992，47：59-64
[15] Y. Izumi， T. Fujita. Iminium salt-catalyzed liquid-phase Beckmann rearrangement ofcyclohexanone oxime[J]. J. Mol. Catal. A：Chem.，1996，106：43-49
[16] J.E. Lyons，P.E. Ellis Jr，H.K. Myers Jr et al.. Oxidation of alkanes [P]. US Patents，1989
[17] M. Hamamoto，K. Nakayama，Y. Nishiyama et al.. Oxidation of organic substrates by a molecularoxygen/aldehyde/heteropolyoxometalate system[J]. J. Org. Chem.，1993，58：6421-6425
[18] N. Mizuno， D.J. Suh. Selective oxidative dehydrogenation of propane at380℃byCs2.5Cu0.08H3.34PV3Mo9O40catalyst precursor[J]. Appl. Catal. A：Gen.，1996，146：249-254
[19] C. Knapp，T. Ui，K. Nagai et al.. Stability of iron in the Keggin anion of heteropoly acid catalystsfor selective oxidation of isobutane[J]. Catal. Today，2001，71：111-119
[20] Y. Seki，N. Mizuno，M. Misono. High-yield liquid-phase oxygenation of methane with hydrogenperoxide catalyzed by12-molybdovanadophosphoric acid catalyst precursor[J]. Appl. Catal. A：Gen.，1997，158：47-51
[21] M. Misono，N. Nojiri. Recent progress in catalytic technology in Japan[J]. Appl. Catal.，1990，64：1-30
[22] V. Parvulescu，C. Anastasescu，C. Constantin et al.. Mono (V，Nb) or bimetallic (V-Ti，Nb-Ti)ions modified MCM-41catalysts：synthesis，characterization and catalysis in oxidation ofhydrocarbons (aromatics and alcohols)[J]. Catal. Today，2003,78：477-485
[23] A.. Griboval，P. Blanchard，L. Gengembre et al..Hydrotreatment catalysts prepared withheteropolycompound：Characterisation of the oxidic precursors [J]. J. Catal.，1999，188：102-110
[24]张龙，王树江.固载杂多酸催化剂PW12/C催化合成二甘醇二苯甲酸酯[J].石油化工，1998，27：564-566
[25] Y. Izumi，K. Urabe. Catalysis of heteropoly acids entrapped in activated carbon [J]. Chem. Lett.，1981，10：663-666
[26]欧阳玉祝，邹晓勇.活性炭吸附硅钨酸催化合成丁酸丁酯[J].化学世界，2000，41：653-654
[27]邓旭忠，周家华，张煜等.活性炭固载磷钨酸催化合成丙酸丁酯[J].香料香精化妆品，2001，3：7-9
[28]于大伟，柳树华.固载杂多酸PW12／SiO2催化合成对苯二甲酸二异辛酯[J].抚顺石油学院学报，1999，19：34-36
[29]张金昌，田小宁，乔聪震.负载离子液体合成十二烷基苯[J].石油化工，2004，33：714-716
[30]阮宇红，刘耀芳，刘植昌等.二氧化硅负载杂多酸对异丁烷与丁烯烷基化的催化作用Ⅰ.催化剂的制备、表征和失活[J]. Chin. J. Catal.，2004，25：948-954
[31] Z. Zhang, L. Zhu, J. Ma et al..Temperature programmed desorption-mass spectrometry study ofNO desorption and decomposition by titania supported12-tungstophosphoric acid [J]. React.Kinet. Catal. Lett.,2002,76:93-101
[32] A. Engin, H. Haluk, K. Gurkan. Production of lactic acid esters catalyzed by heteropoly acidsupported over ion-exchange resins [J].Green Chem.,2003,5:460-466
[33] B. Li, Z. Liu, J. Liu et al.. Preparation, characterization and application in deep catalytic ODS ofthe mesoporous silica pillared clay incorporated with phosphotungstic acid [J]. J. Col. Inter. Sci.,2011,362:450-456
[34] J. Beck，J. Vartuli，W. Roth et al.. A new family of mesoporous molecular sieves prepared withliquid crystal templates[J]. J. Am. Chem. Soc.，1992，114：10834-10843
[35] A. Monnier，F. Schüth，Q. Huo et al.. Cooperative formation of inorganic-organic interfaces in thesynthesis of silicate mesostructures [J]. Science，1993，261：1299
[36] Q. Huo，D. Margolese，U. Ciesla et al.. Generalized synthesis of periodic surfactant/inorganiccomposite materials [J].1994，368：317-321
[37Q. Huo，D.I. Margolese，U. Ciesla et al.. Organization of organic molecules with inorganicmolecular species into nanocomposite biphase arrays [J]. Chem. Mater.，1994，6：1176-1191
[38] S. Inagaki，Y. Fukushima，K. Kuroda. Synthesis of highly ordered mesoporous materials from alayered polysilicate[J]. J. Chem. Soc.，Chem. Commun.，1993：680-682
[39] T. Yanagisawa， T. Shimizu， K. Kuroda et al.. The preparation ofalkyltrimethylammonium-kanemite complexes and their conversion to mocroporous materials[J].Bull. Chem. Soc. Jpn.，1990，63：988-992
[40] C.G. Goltner，M. Antonietti. Mesoporous materials by templating of liquid crystalline phases [J].Adv. mater.，1997，9：431-436
[41] C.G. G ltner，S. Henke，M.C. Weissenberger et al.. Mesoporous silica from lyotropic liquid crystalpolymer templates [J]. Angewandte Chemie International Edition，1998，37：613-616
[42] C. Kresge，M. Leonowicz，W. Roth et al.. Ordered mesoporous molecular sieves synthesized by aliquid-crystal template mechanism [J]. Nature，1992，359：710-712
[43] P.T. Tanev，M. Chibwe，T.J. Pinnavaia. Titanium-containing mesoporous molecular sieves forcatalytic oxidation of aromatic compounds [J]. Nature，1994，368：321-323
[44] P.T. Tanev，T.J. Pinnavaia. A neutral templating route to mesoporous molecular sieves [J].Science，1995，267：865
[45] K.K. Kang，C.H. Park，W.S. Ahn. Microwave preparation of a titanium-substituted mesoporousmolecular sieve [J]. Catal. Lett.，1999，59：45-49
[46] A.. Voegtlin，A.. Matijasic，J. Patarin et al.. Room-temperature synthesis of silicate mesoporousMCM-41-type materials：Influence of the synthesis pH on the porosity of the materials obtained[J].Microporous materials，1997，10：137-147
[47] M. Chatterjee，T. Iwasaki，H. Hayashi et al.. Room-temperature formation of thermally stablealuminium-rich mesoporous MCM-41[J]. Catal. Lett.，1998，52：21-23
[48] W. Lin，J. Chen，Y. Sun et al.. Bimodal mesopore distribution in a silica prepared by calcining awet surfactant-containing silicate gel[J]. J. Chem. Soc.，Chem. Commun.，1995：2367-2368
[49] C.A. Fyfe，G. Fu，Structure organization of silicate polyanions with surfactants：a new approachto the syntheses，structure transformations，and formation mechanisms of mesostructural materials[J]. J. Am. Chem. Soc.，1995，117：9709-9714
[50] K.W. Gallis，C.C. Landry. Synthesis of MCM-48by a phase transformation process [J].Chemistry of Materials，1997，9：2035-2038
[51] M.J. MacLachlan， N. Coombs， G.A. Ozin. Non-aqueous supramolecular assembly ofmesostructured metal germanium sulphides from (Ge4S10)4-clusters [J]. Nature，1999，397：681-684
[52] E. Armengol，M.L. Cano，A. Corma et al.. Mesoporous aluminosilicate MCM-41as a convenientacid catalyst for Friedel–Crafts alkylation of a bulky aromatic compound with cinnamyl alcohol[J]. J. Chem. Soc.，Chem. Commun.，1995，5：519-520
[53] K.R. Kloetstra，H. Bekkum. Catalysis of the tetrahydropyranylation of alcohols and phenols bythe H-MCM-41mesoporous molecular sieve [J]. J. Chem. Res.(S)，1995，26：51-55
[54] K.R. Kloetstra，H. van Bekkum. Base and acid catalysis by the alkali-containing MCM-41mesoporous molecular sieve[J]. J. Chem. Soc.，Chem. Commun.，1995,10：1005-1006
[55] Z.X. Jin，H.W. Tong，G.P. Yong et al.. Synthesis，characterization and application of Ce-MCM-48as a mesoporous molecular sieve [J]. Chin. J. Chem. Phys.，2005，18：1057-1061
[56] G. Qian，G. Lu，D. Ji et al.. Oxidation of cyclohexane over Bi-incorporated MCM-41mesoporousmolecular sieve catalyst with oxygen as oxidant [J]. Chem. Lett.，2005，34：162-163
[57] S. Dapurkar，A. Sakthivel，P. Selvam. Mesoporous V-MCM-41：highly efficient and remarkablecatalyst for selective oxidation of cyclohexane to cyclohexanol [J]. J. Mol. Catal. A：Chem.，2004，223：241-250
[58] L. Chen，X. Zhou，L. Norena et al.. Comparative studies of Zr-based MCM-41and MCM-48mesoporous molecular sieves：Synthesis and physicochemical properties [J]. Appl. Surf. Sci.，2006，253：2443-2451
[59]黄世勇，王海涛，宋艳芬等.杂原子MCM-41分子筛的合成及对环己烷氧化的研究[J].精细化工，2004，21：41-45
[60] Q. Zhang，W. Yang，X. Wang et al.. Coordination structures of vanadium and iron in MCM-41andthe catalytic properties in partial oxidation of methane [J]. Microporous Mesoporous Mater.，2005，77：223-234
[61] C.L. Tsai，B. Chou，S. Cheng et al.. Synthesis of TMBQ using Cu (II)-substituted MCM-41as thecatalyst[J]. Appl. Catal. A：Gen.，2001，208：279-289
[62] Q. Zhang，Y. Wang，Y. Ohishi et al.. Vanadium-containing MCM-41for partial oxidation of loweralkanes [J]. J. Catal.，2001，202：308-318
[63] Y. Xia，R. Mokaya. Highly ordered mesoporous silicon oxynitride materials as base catalysts [J].Angew. Chem.，2003，115：2743-2748
[64]王奂玲，闫亮，赵睿.氨丙基官能化SBA-15介孔分子筛的合成及催化性能的研究[J].分子催化，2005，19：1-6
[65] B. Xu，H. Li，W. Hua et al.. MSU-S (BEA) mesoporous molecular sieve：An active and stablecatalyst for alkylation of hydroquinone [J]. Microporous Mesoporous Mater.，2006，88：191-196
[66]杨丽娜，袁兴东，亓玉台等.介孔有机硅分子筛PMO-SO3H的合成及催化性能[J].石油化工，2003，32：929-932
[67] C. Subrahmanyam，B. Viswanathan，T. Varadarajan. Alkylation of naphthalene with alcohols overacidic mesoporous solids [J]. J. Mol. Catal. A：Chem.，2005，226：155-163
[68] N.Y. He， C.S. Woo， H.G. Kim et al.. Catalytic formation of acetic anhydride overtungstophosphoric acid modified SBA-15mesoporous materials [J]. Appl. Catal. A：Gen.，2005，281：167-178
[69] K.U. Nandhini，B. Arabindoo，M. Palanichamy et al.. Al-MCM-41supported phosphotungsticacid：Application to symmetrical and unsymmetrical ring opening of succinic anhydride [J]. J.Mol. Catal. A：Chem.，2006，243：183-193
[70] E.P. Reddy，L. Davydov，P. Smirniotis. TiO2-loaded zeolites and mesoporous materials in thesonophotocatalytic decomposition of aqueous organic pollutants：the role of the support [J]. Appl.Catal. B：Environ.，2003，42：1-11
[71]郭星翠，孟宪涛，张杰等. SiW12/MCM-41催化剂的合成及对三醋酸甘油酯反应的影响[J].石油化工高等学校学报，2005，18：36-39
[72]张蓉芳，杨春.多金属氧酸盐/介孔分子筛杂化材料的合成——无机前驱的配比和老化温度的影响[J].化学学报，2007，65：1123-1128
[73]张雪峥，乐英红，高滋. PW/SBA-15负载型催化剂的性能研究[J].高等学校化学学报，2001，22：1169-1172
[74] B. Sulikowski，J. Haber，A. Kubacka et al.. Novel “ship-in-the-bottle” type catalyst：evidence forencapsulation of12-tungstophosphoric acid in the supercage of synthetic faujasite [J]. Catal.Lett.，1996，39：27-31
[75] Q.Y. Liu，W.L. Wu，J. Wang et al.. Characterization of12-tungstophosphoric acid impregnated onmesoporous silica SBA-15and its catalytic performance in isopropylation of naphthalene withisopropanol[J]. Microporous Mesoporous Mater.，2004，76：51-60
[76]韩庆玮，杨丽娜，沈健等.改性介孔分子筛催化合成十一碳烯酸异丙酯[J].工业催化，2005，13：21-23
[77] I. Kozhevnikov，K. Kloetstra，A. Sinnema et al.. Study of catalysts comprising heteropoly acidH3PW12O40supported on MCM-41molecular sieve and amorphous silica [J]. J. Mol. Catal. A：Chem.，1996，114：287-298
[78] M.J. Verhoef，P.J. Kooyman，J.A. Peters et al.. A study on the stability of MCM-41-supportedheteropoly acids under liquid-and gas-phase esterification conditions [J]. MicroporousMesoporous Mater.，1999，27：365-371
[79]孙渝，乐英红. MCM-41负载钨磷杂多酸催化剂的性能研究[J].化学学报，1999，57：746-753
[80]杨水金，尹国俊. MCM-41分子筛负载磷钨钼酸催化合成缩醛(酮)[J].化学反应工程与工艺，2007，23：343-347
[81]何静，冯桃，杨佳. HPA/MCM-48催化剂上四氢呋喃开环聚合[J].石油学报：石油加工，2002，18：37-41
[82]张义军，王敏，杨水金.分子筛MCM-48负载硅钨酸催化合成丁酮-21，2-丙二醇缩酮[J].化学试剂，2007，29：69-71
[83]楚文玲，杨向光，叶兴凯.硅钨杂多酸在中孔全硅分子筛HMS上的固载及其催化性能[J].催化学报，1997，18：225-229
[84]武文良，刘琪英，王延.超稳Y沸石负载杂多酸催化剂的制备，表征及催化性能Ⅱ.萘的异丙基化反应[J].石油化工，2003，32：453-457
[85] C.L. Hill. Introduction： polyoxometalates multicomponent molecular vehicles to probefundamental issues and practical problems [J]. Chem. Rev.，1998，98：1-2
[86] C.L. Hill，C.M. Prosser-McCartha. Homogeneous catalysis by transition metal oxygen anionclusters [J]. Coord. Chem. Rev.，1995，143：407-455
[1] B.R. Jermy, A. Pandurangan. A highly efficient catalyst for the esterification of acetic acid usingn-butyl alcohol [J]. J. Mol. Catal. A: Chem.,2005,237:146-154
[2] V. Prassad, K. Jeong, H. Chae et al.. ODS of4,6-DMDBT and light cycle oil over supportedmolybdenum oxide catalysts[J]. Catal. Commun,2008,9:1966–1969
[3] Z.E.A. Abdalla, B. Li, A. Tufail. Direct synthesis of mesoporous (C19H42N)4H3(PW11O39)/SiO2and its catalytic performance in oxidative desulfurization [J]. Colloids Surf., A,2009,341:86-92
[4] A.T. Shah, B. Li, Z.E. Ali Abdalla. Direct synthesis of Ti-containing SBA-16-type mesoporousmaterial by the evaporation-induced self-assembly method and its catalytic performance foroxidative desulfurization [J]. J. col. inter. sci.,2009,336:707-711
[5] R.J.J.Jansen, H.M.Van Veldhuizen et al.. Heteropoly anion on carbon: characterization and use in2,3,6-trimethylphenol oxidation[J]. J. Mol. Catal. A: Chem.,1996,107:241-246
[6] K.M. Rao, R. Gobetto, A. Iannibello et al.. Solid state NMR and IR studies ofphosphomolybdenum and phosphotungsten heteropoly acids supported on SiO2, γ-Al2O3, andSiO2-Al2O3[J]. J. Catal.,1989,119:512-516
[7] E. Rafiee, S. Rashidzadeh, A. Azad. Silica-supported heteropoly acids: Highly efficient catalystsfor synthesis of [alpha]-aminonitriles, using trimethylsilyl cyanide or potassium cyanide [J]. J.Mol. Catal. A: Chem.,2007,261:49-52
[8] G. Yadav, V. Bokade. Novelties of heteropoly acid supported on clay: Etherification of phenethylalcohol with alkanols[J]. Appl. Catal. A: Gen.,1996,147:299-323
[9] B. Bai, J. Zhao, X. Feng. Preparation and characterization of supported photocatalysts:HPAs/TiO2/SiO2composite [J]. Mater. Lett.,2003,57:3914-3918
[10] S. Kumbar, G. Shanbhag, F. Lefebvre et al.. Heteropoly acid supported on titania as solid acidcatalyst in alkylation of p-cresol with tert-butanol [J]. J. Mol. Catal. A: Chem.,2006,256:324-334
[11] Y. Liu, Y. Cao, N. Yi et al.. Vanadium oxide supported on mesoporous SBA-15as highly selectivecatalysts in the oxidative dehydrogenation of propane [J]. J. Catal.,2004,224:417-428
[12] D. Kumar, C. Landry. Immobilization of a Mo, V-polyoxometalate on cationically modifiedmesoporous silica: Synthesis and characterization studies [J]. Microporous Mesoporous Mater.,2007,98:309-316
[13] J. Juan, J. Zhang, M. Yarmo.12-Tungstophosphoric acid supported on MCM-41for esterificationof fatty acid under solvent-free condition [J]. J. Mol. Catal. A: Chem.,2007,267:265-271
[14] T. Soundiressane, S. Selvakumar, S. Ménage et al.. Ru-and Fe-based N, N'-bis(2-pyridylmethyl)-N-methyl-(1S,2S)-1,2-cyclohexanediamine complexes immobilised onmesoporous MCM-41: Synthesis, characterization and catalytic applications [J]. J. Mol. Catal. A:Chem.,2007,270:132-143
[15] Y. Yang, Y. Guo, C. Hu et al.. Lacunary Keggin-type polyoxometalates-based macroporouscomposite films: preparation and photocatalytic activity [J]. Appl. Catal. A: Gen.,2003,252:305-314
[16] A. Monnier, F. Schüth, Q. Huo et al.. Cooperative formation of inorganic-organic interfaces in thesynthesis of silicate mesostructures [J]. Science,1993,261:1299-1303
[17] Y. Liu, Y. Cao, S. Yan et al.. Highly effective oxidative dehydrogenation of propane over vanadiasupported on mesoporous SBA-15silica [J]. Catal. Lett.,2003,88:61-67
[18] B. Jermy, A. Pandurangan. H3PW12O40supported on MCM-41molecular sieves: An effectivecatalyst for acetal formation [J]. Appl. Catal. A: Gen.,2005,295:185-192
[19] L. Fan, L. Xu, G. Gao et al.. A novel polyoxometalate chain constructed from sandwichlanthanide-containing polyanion [Ce(PW11O39)2]10-and sodium ion linker [J]. Inorg. Chem.Commun.,2006,9:1308-1311
[20] X. Yu, L. Xu, X. Yang et al.. Preparation of periodic mesoporous silica-included divacant Kegginunits for the catalytic oxidation of styrene to synthesize styrene oxide [J]. Appl. Surf. Sci.,2008,254:4444-4451
[21] L. Xu, E. Boring, C. Hill. Polyoxometalate-modified fabrics: New catalytic materials forlow-temperature aerobic oxidation [J]. J. Catal.,2000,195:394-405
[22] D. Carriazo, C. Domingo, C. Martn et al.. PMo or PW heteropoly acids supported on MCM-41silica nanoparticles: Characterisation and FT-IR study of the adsorption of2-butanol [J]. J. SolidState chem.,2008,181:2046-2057
[23] J. Zhang, R. Ohnishi, Y. Kamiya et al.. Improved catalytic activity using water for isomerizationof linear butene to isobutene over heteropolyacid catalysts [J]. J. Catal.,2008,254:263-271
[24] Y. Zhang, H. Lü, L. Wang et al.. The oxidation of benzothiophene using the Keggin-type lacunarypolytungstophosphate as catalysts in emulsion [J]. J. Mol. Catal. A: Chem.,2010,332:59-64
[25] I. Kozhevnikov. Sustainable heterogeneous acid catalysis by heteropoly acids [J]. J. Mol. Catal. A:Chem.,2007,262:86-92
[26] B. Gagea, Y. Lorgouilloux, Y. Altintas et al.. Bifunctional conversion of n-decane over HPWheteropoly acid incorporated into SBA-15during synthesis [J]. J. Catal.,2009,265:99-108
[27] P. Sharma, S. Vyas, A. Patel. Heteropolyacid supported onto neutral alumina: characterization andesterification of1oand2oalcohol [J]. J. Mol. Catal. A: Chem.,2004,214:281-286
[28] A. Khder, E. El-Sharkawy, S. El-Hakam et al.. Surface characterization and catalytic activity ofsulfated tin oxide catalyst [J]. Catal. Commun.,2008,9:769-777
[29] I. Roberts, H. Urey. A study of the esterification of benzoic acid with methyl alcohol usingisotopic oxygen [J]. J. Am. Chem. Soc.,1938,60:2391-2393
[30] R. Koster, B. van der Linden, E. Poels et al.. The mechanism of the gas-phase esterification ofacetic acid and ethanol over MCM-41[J]. J. Catal.,2001,204:333-338
[31] W. Chu, X. Yang, X. Ye et al.. Vapor phase esterification catalyzed by immobilizeddodecatungstosilicic acid (SiW12) on activated carbon [J]. Appl. Catal. A: Gen.,1996,145:125-140
[32] T. Peters, N. Benes, A. Holmen et al.. Comparison of commercial solid acid catalysts for theesterification of acetic acid with butanol [J]. Appl. Catal. A: Gen.,2006,297:182-188
[33] X.M. Yan, J.H. Lei, D. Liu et al.. Synthesis and catalytic properties of mesoporousphosphotungstic acid/SiO2in a self-generated acidic environment by evaporation-inducedself-assembly [J]. Mater. Res. Bull.,2007,42:1905-1913
[34] X.M. Yan, P. Mei, J. Lei et al.. Synthesis and characterization of mesoporous phosphotungsticacid/TiO2nanocomposite as a novel oxidative desulfurization catalyst [J]. J. Mol. Catal. A: Chem.,2009,304:52-57
[1] Y. Wei, M. Lu, C.F. Cheung et al.. Functionalization of [MoW25O19]-with Aromatic Amines:Synthesis of the First Arylimido Derivatives of Mixed-Metal Polyoxometalates[J]. Inorg. Chem,2001,40:5489-5490
[2] M. Vazylyev, D. Sloboda-Rozner, A. Haimov et al.. Strategies for oxidation catalyzed bypolyoxometalates at the interface of homogeneous and heterogeneous catalysis[J]. Top. Catal.,2005,34:93-99
[3] S. Shigeta, S. Mori, E. Kodama et al.. Broad spectrum anti-RNA virus activities of titanium andvanadium substituted polyoxotungstates[J]. Antiviral research,2003,58:265-271
[4] R. Hierle, J. Badan, J. Zyss. Growth and characterization of a new material for nonlinear optics:methyl-3-nitro-4-pyridine-1-oxide (POM)[J]. Journal of Crystal Growth,1984,69:545-554
[5] W. Qiu, Y. Zheng, K.A. Haralampides. Study on a novel POM-based magnetic photocatalyst:Photocatalytic degradation and magnetic separation[J]. Chem. Eng. J.,2007,125:165-176
[6] I. Kozhevnikov, K. Matveev. Homogeneous catalysts based on heteropoly acids (review)[J]. Appl.Catal.,1983,5:135-150
[7] I. Kozhevnikov. Catalysis by heteropoly acids and multicomponent polyoxometalates inliquid-phase reactions[J]. Chem. Rev,1998,98:171-198
[8] R.J.J.Jansen, H.M.Van Veldhuizen, H.Van Bekkum. Heteropoly anion on carbon: characterizationand use in2,3,6-trimethylphenol oxidation [J]. J. Mol. Catal. A: Chem.,1996,107:241-246
[9] K.M. Rao, R. Gobetto, A. Iannibello et al.. Solid state NMR and IR studies ofphosphomolybdenum and phosphotungsten heteropoly acids supported on SiO2,γ-Al2O3, andSiO2-Al2O3[J]. J. Catal.,1989,119:512-516
[10] E. Rafiee, S. Rashidzadeh, A. Azad. Silica-supported heteropoly acids: Highly efficient catalystsfor synthesis of [alpha]-aminonitriles, using trimethylsilyl cyanide or potassium cyanide[J]. J. Mol.Catal. A: Chem.,2007,261:49-52
[11] G. Yadav, V. Bokade. Novelties of heteropoly acid supported on clay: Etherification of phenethylalcohol with alkanols[J]. Appl. Catal. A: Gen.,1996,147:299-323
[12] I. Kozhevnikov, A. Sinnema, R. Jansen et al.. New acid catalyst comprising heteropoly acid on amesoporous molecular sieve MCM-41[J]. Catal. Lett.,1994,30:241-252
[13] D. Kumar, C. Landry. Immobilization of a Mo, V-polyoxometalate on cationically modifiedmesoporous silica: Synthesis and characterization studies[J]. Microporous Mesoporous Mater.,2007,98:309-316
[14] J. Juan, J. Zhang, M. Yarmo.12-Tungstophosphoric acid supported on MCM-41for esterificationof fatty acid under solvent-free condition[J]. J. Mol. Catal. A: Chem.,2007,267:265-271
[15] D. Jin, J. Gao, Z. Hou et al.. Microwave assisted in situ synthesis of USY-encapsulated heteropolyacid (HPW-USY) catalysts[J]. Appl. Catal. A: Gen.,2009,352:259-264
[16] C. Shi, R. Wang, G. Zhu et al.. In Situ Synthesis, Characterization of SiPMo-X, and DifferentCatalytic Properties of SiPMo-X and SiPW-X[J]. Eur. J. Inorg. Chem.,2006,2006:3054-3060
[17] B. Gagea, Y. Lorgouilloux, Y. Altintas et al.. Bifunctional conversion of n-decane over HPWheteropoly acid incorporated into SBA-15during synthesis[J]. J. Catal.,2009,265:99-108
[18] Y. Izumi, K. Urabe, M. Onaka. Zeolite, clay, and heteropoly acid in organic reactions[M]. VCH,1992
[19] M.T. Pope, Y. Jeannin, M. Fournier. Heteropoly and isopoly oxometalates[M]. Springer-VerlagBerlin,1983
[20] C.L. Hill. Introduction: PolyoxometalatesMulticomponent Molecular Vehicles To ProbeFundamental Issues and Practical Problems[J]. Chem. Rev.,1998,98:199-218
[21] C.L. Hill, C.M. Prosser-McCartha. Homogeneous catalysis by transition metal oxygen anionclusters[J]. Coord. Chem. Rev.,1995,143:407-455
[22] D.E. Katsoulis, M.T. Pope. New chemistry for heteropolyanions in anhydrous nonpolar solvents.Coordinative unsaturation of surface atoms. Polyanion oxygen carriers[J]. J. Am. Chem. Soc.,1984,106:2737-2738
[23] B.J.S. Johnson, A. Stein. Surface modification of mesoporous, macroporous, and amorphous silicawith catalytically active polyoxometalate clusters[J]. Inorg. Chem,2001,40:801-808
[24] N. Maksimchuk, M. Melgunov, Y.A. Chesalov et al.. Aerobic oxidations of [alpha]-pinene overcobalt-substituted polyoxometalate supported on amino-modified mesoporous silicates[J]. J. Catal.,2007,246:241-248
[25] T. Baba, H. Watanabe, Y. Ono. Generation of Acidic Sltes In Metal Salts of Heteropolyacids[J]. J.Phys. Chem.,1983,87:2406-2411.
[26] L.R. Pizzio, M.N. Blanco. Preparation and characterization of transition metal-modified lacunaryKeggin11-tungstophosphates supported on carbon[J]. Mater. Lett.,2007,61:719-724.
[27] Y. Liu, Y. Cao, S. Yan et al.. Highly effective oxidative dehydrogenation of propane over vanadiasupported on mesoporous SBA-15silica[J]. Catal. Lett.,2003,88:61-67
[28] H. Niiyama, Y. Saito, E. Echigoya. Acid-Type Catalysis by Metal Cation-Substituted Hetero-PolyCompounds[J]. Stud. Surf. Sci. Catal.,1981,7:1416-1417
[29] B. Jermy, A. Pandurangan. H3PW12O40supported on MCM-41molecular sieves: An effectivecatalyst for acetal formation[J]. Appl. Catal. A: Gen.,2005,295:185-192
[30] L. Fan, L. Xu, G. Gao et al.. A novel polyoxometalate chain constructed from sandwichlanthanide-containing polyanion [Ce (PW11O39)2]10-and sodium ion linker[J]. Inorg. Chem.Commun.,2006,9:1308-1311
[31] P. Sharma, S. Vyas, A. Patel. Heteropolyacid supported onto neutral alumina: characterization andesterification of1oand2oalcohol[J]. J. Mol. Catal. A: Chem.,2004,214:281-286
[32] A. Khder, E. El-Sharkawy, S. El-Hakam et al.. Surface characterization and catalytic activity ofsulfated tin oxide catalyst[J]. Catal. Commun.,2008,9:769-777
[1] I. Kozhevnikov. Heteropoly acids and related compounds as catalysts for fine chemical synthesis[J].Catal. Rev.,1995,37:311-352
[2] S. Damyanova, M. Cubeiro, J. Fierro. Acid-redox properties of titania-supported12-molybdophosphates for methanol oxidation[J]. J. Mol. Catal. A: Chem.,1999,142:85-100
[3] A. Rives, E. Payen, R. Hubaut et al.. Silica and alumina impregnated with dimethylformamidesolutions of molybdophosphoric or tungstophosphoric acids for hydrotreatment reactions[J]. Catal.Lett.,2001,71:193-201
[4] E. Lopez-Salinas,J. Hernandez-Cortez, I. Schifter et al.. Thermal stability of12-tungstophosphoricacid supported on zirconia[J]. Appl. Catal. A: Gen.,2000,193:215-225
[5] A. de Angelis, S. Amarilli, D. Berti et al..Alkylation of benzene catalysed by supportedheteropolyacids[J]. J. Mol. Catal. A: Chem.,1999,146:37-44
[6] Y. Izumi, K. Urabe. Catalysis of heteropoly acids entrapped in activated carbon[J]. Chem.Lett.,1981,10:663-666
[7] J. Beck, J. Vartuli, W. Roth et al.. A new family of mesoporous molecular sieves prepared withliquid crystal templates[J]. J. Am. Chem. Soc.,1992,114:10834-10843
[8] A. Corma. From microporous to mesoporous molecular sieve materials and their use in catalysis[J].Chem. Rev,1997,97:2373-2420
[9] Fre′de′rique Marme, Gise`le Coudurier, Jacques C. Ve′drine. Acid-type catalytic properties ofheteropolyacid H3PW12O40supported on various porous silica-based materials[J]. MicroporousMesoporous Mater.,1998,22:151-163
[10] S. Damyanova, L. Dimitrov a, R. Mariscal et al.. Immobilization of12-molybdophosphoric and12-tungstophosphoric acids on metal-substituted hexagonal mesoporous silica[J]. Appl. Catal. A:Gen.,2003,256:183-197
[11] I. Kozhevnikov. Catalysis by polyoxometalates[M]. Wiley,2002
[12] D. Kumar, C.C. Landry. Immobilization of a Mo, V-polyoxometalate on cationically modifiedmesoporous silica: Synthesis and characterization studies[J]. Microporous Mesoporous Mater.,2007,98:309-316
[13] M. Decottignies, J. Phalippou, J. Zarzycki. Synthesis of glasses by hot-pressing of gels[J]. J.Mater. Sci.,1978,13:2605-2618
[14] C.R. Deltcheff, M. Fournier, R. Franck et al.. Vibration investigations of polyoxometalates.2.Evidence for Anion-Anion interactions in molybdenum (VI) and tungsten (VI) compounds relatedto the Keggin structure[J]. Inorg. Chem.,1983,22:207-216
[15] L. Hu, S. Ji, Z. Jiang et al.. Direct synthesis and structural characteristics of ordered SBA-15mesoporous silica containing tungsten oxides and tungsten carbides[J]. J. Phys. Chem. C.,2007,111:15173-15184
[16] A. Ghanbari-Siahkali, A. Philippou, J. Dwyer et al.. The acidity and catalytic activity ofheteropoly acid on MCM-41investigated by MAS NMR, FTIR and catalytic tests[J]. Appl. Catal.A: Gen.,2000,192:57-69
[17] T. Zepeda, B. Pawelec, J. Fierro et al.. Synthesis and characterization of P-modified mesoporousCoMo/HMS-Ti catalysts[J]. Microporous Mesoporous Mater.,2008,111:493-506
[18] A. Ghanbari-Siahkali, A. Philippou, J. Dwyer et al.. The acidity and catalytic activity ofheteropoly acid on MCM-41investigated by MAS NMR, FTIR and catalytic tests[J]. Appl. Catal.A: Gen.,2000,192:57-69
[19] X. Yan, G. Su, L. Xiong. Oxidative desulfurization of diesel oil over Ag-modified mesoporousHPW/SiO2catalyst [J]. J. Fuel Chem. Technol.,2009,37:318-323
[20] X.M. Yan, J.H. Lei, D. Liu et al.. Synthesis and catalytic properties of mesoporousphosphotungstic acid/SiO2in a self-generated acidic environment by evaporation-inducedself-assembly[J]. Mater. Res. Bull.,2007,42:1905-1913
[1] F. Marme, G. Coudurier, J.C. Védrine. Acid-type catalytic properties of heteropolyacid H3PW12O40supported on various porous silica-based materials[J]. Microporous Mesoporous Mater.,1998,22:151-163
[2] S. Damyanova, L. Dimitrov, R. Mariscal,et al.. Immobilization of12-molybdophosphoric and12-tungstophosphoric acids on metal-substituted hexagonal mesoporous silica[J]. Appl. Catal. A:Gen.,2003,256:183-197
[3] B. Pawelec, S. Damyanova, R. Mariscal,et al.. HDS of dibenzothiophene over polyphosphatessupported on mesoporous silica[J]. J. Catal.,2004,223:86-97
[4] Y. Liu, K. Murata, M. Inaba. Direct oxidation of benzene to phenol by molecular oxygen overcatalytic systems containing Pd (OAc)2and heteropolyacid immobilized on HMS or PIM[J]. J. Mol.Catal. A: Chem.,2006,256:247-255
[5] Y. Liu, K. Murata, M. Inaba,et al.. Selective oxidation of propylene to acetone by molecular oxygenover Mx/2H5-x[PMo10V2O40]/HMS (M=Cu2+, Co2+, Ni2+)[J]. Catal. Commun.,2003,4:281-285
[6] T. Soundiressane, S. Selvakumar, S. Ménage, et al.. Ru-and Fe-basedN,N'-bis2-pyridylmethyl)-N-methyl-(1S,2S)-1,2-cyclohexanediamine complexes immobilised onmesoporous MCM-41: Synthesis, characterization and catalytic applications[J]. J. Mol. Catal. A:Chem.,2007,270:132-143
[7] Y. Yang, Y. Guo, C. Hu, et al.. Lacunary Keggin-type polyoxometalates-based macroporouscomposite films: preparation and photocatalytic activity[J]. Appl. Catal. A: Gen.,2003,252:305-314
[8] G.D. Stucky, Q. Huo, A. Firouzi, et al..Directed synthesis of organic/inorganic compositestructures[J]. Studies in Surface Science and Catalysis,1997,105:3-28
[9] Y. Liu, Y. Zhang, Y. Hu, et al.. Hydrothermal Synthesis of Single-crystal-AgVO3Nanowires andRibbon-like Nanowires[J]. Chem. Lett.,2005,34:146-147
[10] H. Chon, S.K. Ihm, Y.S. Uh. Progress in zeolite and microporous materials[M], Elsevier,1997
[11] L. Fan, L. Xu, G. Gao, et al.. A novel polyoxometalate chain constructed fromsandwichlanthanide-containing polyanion [Ce(PW-11O39)2]10and sodium ion linker[J]. Inorg.Chem. Commun.,2006,9:1308-1311
[12] Y. Izumi, K. Urabe, M. Onaka. Zeolite, clay, and heteropoly acid in organic reactions[M] VCH,1992
[13] P.T. Tanev, M. Chibwe, T.J. Pinnavaia. Titanium-containing mesoporous molecular sieves forcatalytic oxidation of aromatic compounds[J]. Nature,1994,368:321-323
[14] C.G. Goltner, M. Antonietti. Mesoporous materials by templating of liquid crystallinephases[J].Advanced materials,1997,9:431-436
[15] P. Sharma, S. Vyas, A. Patel. Heteropolyacid supported onto neutral alumina: characterization andof1o and2o alcohol,[J]. J. Mol. Catal. A: Chem.,2004,214:281-286
[16] A. Khder, E. El-Sharkawy, S. El-Hakam, et al.. Surface characterization and catalytic activity ofsulfated tin oxide catalyst[J]. Catal. Commun.,2008,9:769-777