NO_x吸附—分解催化新体系构建及过程特性研究
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摘要
氮氧化物(NO_x)是主要的大气污染物之一，也是形成光化学烟雾的主要前驱物，控制和治理氮氧化物污染一直是国际环保领域的研究热点。在众多的脱硝方法中催化分解法和选择性催化还原法(SCR)的研究和应用最为广泛。以氨气为还原剂的SCR技术已在工业中广泛应用，但投资和运行费用较高，且存在氨泄露、管道腐蚀和储运安全等问题。催化分解法无需还原剂、方法简单、且投资和运行费用较低，但迄今人们所开发的相关催化剂其催化活性大都因气相中氧气或水蒸汽的存在而受到抑制，并且催化剂起活温度高，大多在300℃以上。因此，有关NO_x催化分解新体系的研究开发一直都是该领域的研究热点。将环境友好型杂多化合物(heteropoly compounds简写为HPCs)应用于NO_x的催化分解可望避免氧气与水蒸汽抑制的问题，显示了很好的研究开发前景。
本论文通过系统的实验设计与优化，制备并考察了杂多化合物及其负载型催化剂对NO_x的脱除效果，构建了具有吸附-分解NO_x功能的杂多化合物催化新体系，揭示了体系性能的构效关系，并借助现代化分析手段，揭示了吸附-分解过程机理。主要内容分为三部分：
第一部分，初步确定了杂多化合物催化新体系的工艺条件，在有氧条件下考察了空速、水蒸汽含量、反应温度对体系脱硝性能的影响。结果表明：最佳的工艺条件为水蒸汽含量4．2％，反应温度150℃，空速5298h~(-1)。杂多化合物催化剂有效解决了传统催化剂所存在的氧气、水蒸汽抑制和起活温度高等问题。
第二部分，采用乙醚萃取法等制备出一系列具有Keggin结构的杂多化合物，考察了其对NO_x的吸附性能，筛选出了最佳物种HPW；在此基础上，选择碳纳米管(CNT)、二氧化钛(TiO_2)、铈锆氧化物、Y分子筛，活性炭、堇青石和活性白土为载体，采用常规浸渍法，制备出一系列的负载型磷钨酸催化剂，考察其对NO_x的吸附性能，筛选出优良体系HPW／CNT、HPW／TiO_2和HPW／CeO_2，对其进行了XRD、BET、IR、TEM表征。结果表明：混酸(V_(HNO3)：V_(H2SO4)=1：3)能在CNT上引入C=O、COO-等含氧基团，以水为浸渍剂、混酸处理后的CNT为载体，HPW的最佳负载量为70％时，HPW／CNT催化体系对NO_x的吸附性能最佳，吸附率高达73．5％；以水为浸渍剂，HPW负载量为20％，TiO_2锻烧温度为500℃时，所制备的HPW／TiO_2催化体系对NO_x的吸附性能最佳，吸附率可达62．8％；HPW负载量为70％时，HPW／CeO_2对NO_x的吸附性能最佳，吸附率高达75．3％。以上催化体系对NO_x的吸附性能与其比表面积相关性不大，主要是负载其上的HPW的假液相过程。
第三部分，对最终优选体系HPW和HPW／CeO_2吸附-分解NO_x的过程特性和机理进行了研究。HPW／CeO_2的适宜吸附条件为：氧气含量8％，水蒸汽含量4．2％，吸附反应温度170℃，空速2649h~(-1)～5298h~(-1)，与初步确定的工艺条件基本一致。计算出150℃下两种体系的饱和吸附量分别为50．5mg NO_2／g和85．6mgNO_2／g。通过IR表征揭示了吸附质与催化剂的作用方式，通过GC-MS检测确认了吸附质催化分解为N_2的有效性。
NO_x is one of the main air pollutants .It is also the main precursor of photochemistry fog. It has been a hot point in the international environmental research field to control and treat NO_x pollution. Among various denitrification methods, catalytic decomposition and selective catalytic reduction (SCR) were adopted widely. SCR technology with ammonia as reducing agent has being widely used commercially for denitrification of flue gas. But ammonia which is hard to transport is liable to leak and is also corrosive to pipe line. Investment and running cost of SCR with NH_3 as reducing agent is high. Decomposition of NO_x is a simple method without reducing agent. Furthermore, the cost of investment and running of NO_x decomposition is low. But most catalysts used are active only in high temperature and may strongly be inhibited by oxygen and water in the flue gas. Hence, the development of new catalyst systems for NO_x conversion has becoming the focus of worldwide researches. Heteropoly compounds (HPCs) are functional material which are unharmful to the environment. Using heteropoly compounds as catalysts for NO_x decomposition could overcome the negative effects caused by O_2 and H_2O in the flue gas and is therefore promising in the treatment of NO_x.
In this paper, many kinds of HPCs and supported HPCs were prepared and evaluated concerning their de-NO_x efficiencies, and new catalyst systems as functional material for adsorption-decomposotion of NO_x were constructed. The relationship between the catalyst structure and the denitrification performance was studied. The mechanism of the process of NO_x adsorption-decomposotion was revealed with the aid of modern analytical instruments.
The paper is composed of three sections.
In the first section, test conditions for the new catalyst systems of heteropoly compounds were confirmed primarily. In the presence of oxygen, the effects of space velocity, water vapor concentration and reaction temperature on NO_x convertion were discussed. The experimental results showed that the optimum test conditions are 4.2% (v/v) of water vapor concentration. 150℃of reaction temperature and 5298h~(-1) of space velocity. Several intrinsic drawbacks existed in the conventional catalysts, including oxygen, water and active temperature inhibition, were overcomed effectively.
In the second section, NO_x adsorption efficiencies of hetepoly compounds with Keggin structure prepared by means of ethanol-extraction were evaluated. The results showed that among the prepared HPCs, H_3PW_(12)O_(40) (HPW) was the best adsorbent. Subsequently, HPW was impregnated on several supports including carbon nanotube (CNT), Titania (TiO_2), Cerium and zirconium oxides, Y-type zeolite, activated carbon, cordierite and activated soil to form corresponding catalyst systems. NO_x adsorption efficiencies of supported HPW were evaluated so as to find good supports and their corresponding catalyst systems. After that, the optimum catalyst systems including HPW/CNT, HPW/TiO_2 and HPW/CeO_2 were characterized by XRD, BET, IR and TEM. The results showed that Mixed HNO_3/H_2SO_4, with a volume ratio of 1:3. could produce functional groups such as COO- and C=O on the surface of CNT, which made the dispersion of CNT easier in the aqueous solution. At a HPW loading of 70%. the best adsorption efficiency of NO_x by HPW/CNT catalyst system, prepared using water as impregnation solvent and HNO_3/H_2SO_4 -modified CNT as support, could be achieved as 73.5%. The adsorption efficiency of HPW/TiO_2 can reach 62.8% at most. when the HPW loading was 20% and the calcination temperature of TiO_2 was 500℃.
The adsorption efficiency of HPW/CeO_2 can reach 75.3% at most, when the HPW loading was 70%. NO_x adsorptive performence is mainly relevant to the pseudoliquidphase property of HPW supported on the supports and unsensitive to the catalyst surface.
In the third section, the characteristic and mechanism of the process of NO_x adsorption-decomposition by HPW and HPW/CeO_2 were studied. The favourable adsorption conditions for HPW/CeO_2 are 8% of O_2, 4.2% of water vapor concentration, 170℃of reaction temperature and a space velocity within 2649h~(-1) to 5298h~(-1). The favourable adsorptian conditions for HPW/CeO_2 are nearly identical to the former. The saturated adsorption amounts of NO_x at 150℃of reaction temperature by HPW and HPW/CeO_2 were detected to be 50.5mg NO_2/g and 85.6 mg NO_2/g respectively. With the aid of IR and GC-MS, the NO_x-catalyst interaction mode and process effectiveness for NO_x conversion to N_2 were revealed.
本论文通过系统的实验设计与优化，制备并考察了杂多化合物及其负载型催化剂对NO_x的脱除效果，构建了具有吸附-分解NO_x功能的杂多化合物催化新体系，揭示了体系性能的构效关系，并借助现代化分析手段，揭示了吸附-分解过程机理。主要内容分为三部分：
第一部分，初步确定了杂多化合物催化新体系的工艺条件，在有氧条件下考察了空速、水蒸汽含量、反应温度对体系脱硝性能的影响。结果表明：最佳的工艺条件为水蒸汽含量4．2％，反应温度150℃，空速5298h~(-1)。杂多化合物催化剂有效解决了传统催化剂所存在的氧气、水蒸汽抑制和起活温度高等问题。
第二部分，采用乙醚萃取法等制备出一系列具有Keggin结构的杂多化合物，考察了其对NO_x的吸附性能，筛选出了最佳物种HPW；在此基础上，选择碳纳米管(CNT)、二氧化钛(TiO_2)、铈锆氧化物、Y分子筛，活性炭、堇青石和活性白土为载体，采用常规浸渍法，制备出一系列的负载型磷钨酸催化剂，考察其对NO_x的吸附性能，筛选出优良体系HPW／CNT、HPW／TiO_2和HPW／CeO_2，对其进行了XRD、BET、IR、TEM表征。结果表明：混酸(V_(HNO3)：V_(H2SO4)=1：3)能在CNT上引入C=O、COO-等含氧基团，以水为浸渍剂、混酸处理后的CNT为载体，HPW的最佳负载量为70％时，HPW／CNT催化体系对NO_x的吸附性能最佳，吸附率高达73．5％；以水为浸渍剂，HPW负载量为20％，TiO_2锻烧温度为500℃时，所制备的HPW／TiO_2催化体系对NO_x的吸附性能最佳，吸附率可达62．8％；HPW负载量为70％时，HPW／CeO_2对NO_x的吸附性能最佳，吸附率高达75．3％。以上催化体系对NO_x的吸附性能与其比表面积相关性不大，主要是负载其上的HPW的假液相过程。
第三部分，对最终优选体系HPW和HPW／CeO_2吸附-分解NO_x的过程特性和机理进行了研究。HPW／CeO_2的适宜吸附条件为：氧气含量8％，水蒸汽含量4．2％，吸附反应温度170℃，空速2649h~(-1)～5298h~(-1)，与初步确定的工艺条件基本一致。计算出150℃下两种体系的饱和吸附量分别为50．5mg NO_2／g和85．6mgNO_2／g。通过IR表征揭示了吸附质与催化剂的作用方式，通过GC-MS检测确认了吸附质催化分解为N_2的有效性。
NO_x is one of the main air pollutants .It is also the main precursor of photochemistry fog. It has been a hot point in the international environmental research field to control and treat NO_x pollution. Among various denitrification methods, catalytic decomposition and selective catalytic reduction (SCR) were adopted widely. SCR technology with ammonia as reducing agent has being widely used commercially for denitrification of flue gas. But ammonia which is hard to transport is liable to leak and is also corrosive to pipe line. Investment and running cost of SCR with NH_3 as reducing agent is high. Decomposition of NO_x is a simple method without reducing agent. Furthermore, the cost of investment and running of NO_x decomposition is low. But most catalysts used are active only in high temperature and may strongly be inhibited by oxygen and water in the flue gas. Hence, the development of new catalyst systems for NO_x conversion has becoming the focus of worldwide researches. Heteropoly compounds (HPCs) are functional material which are unharmful to the environment. Using heteropoly compounds as catalysts for NO_x decomposition could overcome the negative effects caused by O_2 and H_2O in the flue gas and is therefore promising in the treatment of NO_x.
In this paper, many kinds of HPCs and supported HPCs were prepared and evaluated concerning their de-NO_x efficiencies, and new catalyst systems as functional material for adsorption-decomposotion of NO_x were constructed. The relationship between the catalyst structure and the denitrification performance was studied. The mechanism of the process of NO_x adsorption-decomposotion was revealed with the aid of modern analytical instruments.
The paper is composed of three sections.
In the first section, test conditions for the new catalyst systems of heteropoly compounds were confirmed primarily. In the presence of oxygen, the effects of space velocity, water vapor concentration and reaction temperature on NO_x convertion were discussed. The experimental results showed that the optimum test conditions are 4.2% (v/v) of water vapor concentration. 150℃of reaction temperature and 5298h~(-1) of space velocity. Several intrinsic drawbacks existed in the conventional catalysts, including oxygen, water and active temperature inhibition, were overcomed effectively.
In the second section, NO_x adsorption efficiencies of hetepoly compounds with Keggin structure prepared by means of ethanol-extraction were evaluated. The results showed that among the prepared HPCs, H_3PW_(12)O_(40) (HPW) was the best adsorbent. Subsequently, HPW was impregnated on several supports including carbon nanotube (CNT), Titania (TiO_2), Cerium and zirconium oxides, Y-type zeolite, activated carbon, cordierite and activated soil to form corresponding catalyst systems. NO_x adsorption efficiencies of supported HPW were evaluated so as to find good supports and their corresponding catalyst systems. After that, the optimum catalyst systems including HPW/CNT, HPW/TiO_2 and HPW/CeO_2 were characterized by XRD, BET, IR and TEM. The results showed that Mixed HNO_3/H_2SO_4, with a volume ratio of 1:3. could produce functional groups such as COO- and C=O on the surface of CNT, which made the dispersion of CNT easier in the aqueous solution. At a HPW loading of 70%. the best adsorption efficiency of NO_x by HPW/CNT catalyst system, prepared using water as impregnation solvent and HNO_3/H_2SO_4 -modified CNT as support, could be achieved as 73.5%. The adsorption efficiency of HPW/TiO_2 can reach 62.8% at most. when the HPW loading was 20% and the calcination temperature of TiO_2 was 500℃.
The adsorption efficiency of HPW/CeO_2 can reach 75.3% at most, when the HPW loading was 70%. NO_x adsorptive performence is mainly relevant to the pseudoliquidphase property of HPW supported on the supports and unsensitive to the catalyst surface.
In the third section, the characteristic and mechanism of the process of NO_x adsorption-decomposition by HPW and HPW/CeO_2 were studied. The favourable adsorption conditions for HPW/CeO_2 are 8% of O_2, 4.2% of water vapor concentration, 170℃of reaction temperature and a space velocity within 2649h~(-1) to 5298h~(-1). The favourable adsorptian conditions for HPW/CeO_2 are nearly identical to the former. The saturated adsorption amounts of NO_x at 150℃of reaction temperature by HPW and HPW/CeO_2 were detected to be 50.5mg NO_2/g and 85.6 mg NO_2/g respectively. With the aid of IR and GC-MS, the NO_x-catalyst interaction mode and process effectiveness for NO_x conversion to N_2 were revealed.
引文
[1]叶代启．烟气中氮氧化物污染的治理[J]．环境保护科学，1999，4：147-150．
[2]赵惠富．污染气体NO_x的形成和控制[M]．科学出版社，1993．
[3]许春丽，李保新．日本大气污染控制对策及现状[J]．环境科学动态，2001， 3：33-36．
[4]李玉江，吴涛．德国燃煤电厂氮氧化物的控制技术[J]．环境科学研究，2000， 13(4)：47-49．
[5]李恒远．中国能源环保与政策法规[J]．环境与科学，2001，10：24-25．
[6] Koebel M, Madia G, Elsener M. Selective catalytic reduction of NO and NO_2 at low temperature [J]. Catalysis Today, 2002, 73: 239-247.
[7] An W Z, Zhang Q L, Chuang K T, et al. A hydrophobic Pt-Fluorinate carbon catalyst for reaction of NO with NH_3 [J]. Industrial & Engineering Chemistry Research, 2002, 41: 27-31.
[8]朱景利，张金昌，马润宇等．改性贵金属催化剂催化还原脱除NO[J]．坏 境科学，2006，27(8)：1508-1511．
[9] Burch R, Coleman M D. An investigation of the NO/H_2/O_2 reaction on noble-metal catalysts at low temperatures under lean-burn conditions [J]. Applied Catalysis B: Environmental, 1999, 23: 115-121.
[10] Garcia-Cortes J M, Perez-Ramirez J, Illan-Gomez M J, et al. Comparative study of Pt-based catalysts on different supports in the low-temperature de-NO_x-SCR with propane [J]. Applied Catalysis B: Environmental, 2001, 30: 399-408.
[11] Roberge D, Anuj R, Kaliaguine S, et al. Selective catalytic reduction of NO under ambient conditions using ammonia as reducing agent and MFI zeolites as catalysts [J]. Applied Catalysis B: Environmental, 1996, 10(4): 237-243.
[12] Richter M. Eckelt R, Parlitz B, et al. Low-temperature conversion of NO_x to N_2 by zeolite-fixed ammonium ions[J]. Applied Catalysis B: Environmental. 1998, 15: 129-146.
[13] Richter M, Trunschke A. Bentrup U, et al. Selective catalytic reduction of nitric oxide by ammonia over egg-shell MnO_x/NaY composite catalysts [J]. Journal of Catalysis, 2002, 206: 98-113.
[14]朱华清，王建国，关春梅．NH_4β分子筛上NO的低温催化还原[J]．燃料 化学学报，2001，29(S)：63-65．
[15]张强，许世森，王志强．选择性催化还原烟气脱硝进展及工程应用[J]．热 力发电，2004，(4)：1-7．
[16] Kapteijn F, Singoredjo L, Andreini A, et al. Activity and selectivity of pure manganese oxides in the selective catalytic reduction of nitric oxide with ammonia [J]. Applied Catalysis B: Environmental. 1994, 3(223): 173-189.
[17] Kijlstra W S, Brands D S, Smit H I, et al. Mechanism of the selective catalytic reduction of NO with NH_3 over MnO_x/Al_2O_3[J]. Journal of Catalysis, 1997. 171:219-230.
[18]伍斌，童志权，黄妍．MnO_2／NaY催化剂上NH_3低温选择催化还原NO_x[J]．石 油化工，2006，35(2)：178-182．
[19] Qi G, Yang R T, Chang R. MnO_x-CeO_2 mixed oxides prepared by co-precipitation for selective catalytic reduction of NO with NH_3 at low temperature [J]. Applied Catalysis B: Environmental, 2004, 51(2): 93-106.
[20]唐晓龙，郝吉明，徐文国等．新型MnO_x催化剂用于低温NH_3选择性催化 还NO[J]．催化学报，2006，27(10)：843-848．
[21]唐晓龙，郝吉明，徐文国等．低温条件下Nano-MnO_x上NH_3选择性催化 还原NO[J]．环境科学，2007，28(2)：289-294．
[22] Lázaro M J, Gálvez M E, Suelves I, et al. Low cost catalytic for NO_xreduction.3.NO reduction tests using NH_3 as reducing agent [J]. Fuel, 2004. 83:875-884.
[23] Yoshikawa M, Yasutake A, Mochida I. Low-temperature selective catalyticreduction of NO_x by metal oxides supported on active carbon fibers [J].Applied Catalysis A: General. 1998, 73: 239-245.
[24]杨超，张俊丰，童志权等．活性炭低温催化还原NO_x影响因素及反应机理??分析[J]．环境科学研究，2006，19(4)：86-90．
[25] Huang B C. Huang R, Jin D J et al. Low temperature SCR of NO with NH_3 over carbon nanotubes supported vanadium oxides [J]. Catalysis Today, 2007. 126 (3-4): 279-283.
[26]胡长文，高丽娟，王恩波等．钨系Keggin结构杂多酸的酸强度及催化反 应特性[J]．东北师大学报自然科学版，1995，2：62-70．
[27]王恩波，胡长文，许林．多酸化学导论[M]．北京：化学工业出版社，1998： 171-172．
[28] Yang R T, Chen N. A new approach to decomposition of nitric oxide usingsorbent/catalyst without reducing gas:use of heteropoly compounds [J]. Ind.Eng. Chem. Res, 1994, 33: 825-831.
[29] Chen N, Yang R T. Activation of nitric oxide by heteropoly compounds:structure of nitric-oxide linkages in tungstophosphoric acid with Keggin units[J].Journal of Catalysis, 1995, 157:76-86.
[30] Belanger R, Moffat J B. A comparative study of adsorption and reaction ofnitrogen oxides on 12-tungstophoric, 12-tungstosilicic, and12-molybdophosphoric acid [J]. Journal of Catalysis, 1995, 152: 179-188.
[31] Kozhevnikova E F, Kozhevnikov I .V. Calorimetric study of the acidity ofbulk and silica-supported heteropoly acid H_3PW_(12)O_(40) [J]. Journal of Catalysis.224(1): 164-169,2004.
[32] Belanger R, Moffat J B. The sorption and reduction of nitrogen oxides by12-tungstophoric and its ammonium salt [J]. Catalysis Today, 1998. 40:297-306.
[33] Andrew M. Herring, Robert L, et al. A Comparison of the Interaction of NitricOxide with the Heteropolytungstic Acids H_3PW_(12)O_(40), H_(0.5)Cs_(2.5)PW_(12)O_(40).HMgPW_(12)O_(40), HgSiW_(11)O_(38), H_4SiW_(12)O_(40), and H_(10)CoW_(12)O_(42)[J]. Journal ofPhysical Chemistry B: 2000. 104: 4653-4660.
[34] Hodjati S, Petit C. Removal of NO_x from a lean exhaust gas by adsorption onheteropoly acids reversible sorption of nitrogen oxides in H_3PW_(12)O_(40)·6H_2O [J].Journal of Catalysis. 2001, 197: 324-334.
[35] Belanger R, Moffat J B. A self-contained catalyst for the reduction of NO_2 [J]. Applied Catalysis B: Environmental, 1997, 13: 167-173.
[36]吴越，叶兴凯，杨向光等．杂多酸的固载化-关于制备负载型酸催化剂的一 般原理[J]．分子催化，1998，10(4)：299-315．
[37] Chu W L, Yang X G, Ye X K. et al. Adsorption of PMo_(12) and SiMo_(12) onActivated Carbon in Aqueous and Acidic Media [J]. Langmuir, 1996, 12(17):4185-4189.
[38] Robert L M, Sukrithirra K B, Andrew M, et al. In situ IR and temperatureprogrammed desorption-mass spectrometry study of NO adsorption anddecomposition by silica supported 12-tungstophosphoric acid [J]. CatalysisToday, 1998,42: 145-157.
[39] Zhang Zh L, Zhu L L, Ma J, et al. Temperature programmed desorption-massNO desorption by HPW [J] React. Kinet. Catal. Lett, 2002, 76(1): 93-101.
[40] Damyanova S, Fierro J L G. Surface properties of titania-supported12-molybdsphoric acid hydrodesulphurization catalysts [J]. Applied CatalysisA: General, 1996, 144: 59-77.
[41] Thomas S, Vaezzadeh K, Pitchon V. Supported heteropolyacids for NO_xstorage and reduction [J]. Topics in Catalysis, 2004, 30/31: 207-213.
[42] Miguel Angel G, Veronique Pitchon, Alain Kiennemann. Storage and reductionof lean-NO_x by using H_3PW_(12)O_(40)·6H_2Osupported on Ti_xZr_(1-x)O_4 [J]. CatalysisToday. 2005, 107-108:60-67.
[43] Miguel Angel G, Veronique Pitchon, Alain Kiennemann. Removal of NO_x fromlean exhaust gas by storage-reduction on H_3PW_(12)O_(40)·6H_2O supported onCe_xZr_(4-x)O_8 [J]. Environ. Sci. Technol. 2005. 39: 638-644.
[44] Damyanova S,Pimitrov L.MariscalR, et al. Immobilization of12-molybdophosphoric and 12-tungstophosphoric acids on metal-substitutedhexagonal mesoporous silica [J]. Applied Catalysis A: General, 2003, 256(1/2): 183-197.
[45] Vaezzadeh K, Petit C, Pitchon V, et al. A new concept for the removal of NO_xfrom a lean exhaust gas using storage on H_3PW_(12)O_(40)·6H_2O. a very fast??desorption and a reduction over a TWC [J]. Catalysis Communications, 2002. 3: 179-183.
[46]王睿，吴丹，赵大传等．实现NO_x吸附分解的杂多化合物催化新体系研究 [J]．现代化工，2006，26(S2)：120-123．
[47]刘俊峰．硅钼杂多酸合成工艺研究[J]．无机盐工业，2001，33(6)：12-13．
[48]张波，付湘清，张汉鹏等．介孔分子筛固载Keggin结构钼钨磷杂多酸的 制备及表征[J]．化学世界，2002，5：230-233．
[49]金明善，翁永根，董和泉等．改性杂多酸催化剂的制备及其在甲缩醛合成 中的催化活性[J]．复旦学报(自然科学版)，2003，42(3)：280-285．
[50] George A, Tsigdinos. Preparation and Characterization of 12-Molybdophosphoric and 12-Molybdosilicic Acids and Their Metal Salts [J]. Ind. Eng. Chem, 1974,13(4):1185-1197 .
[51]余新武，周锦华，陈维莉等．过渡金属杂多钨酸盐的合成、表征及抗结核 病菌活性[J]．湖北师范学院学报，2001，21(4)：11-14．
[52]苏占华，徐学勤，马慧媛等．过渡金属取代的钨铝杂多配合物的制备、表 征和性质[J]．无机化学学报，2005，21(5)：647-652．
[53] Linda C J, Hellmut G K, Evgenya V. A microcalorimetric investigation of heteropolyacids [J]. Microporous matericals, 1993,1(5): 313-322.
[54] Gayraud P Y, Stewart I H, Derouane A H S B, et al. Performance of potassium 12-tungstophosphoric salts as catalysts for isobutane/butene alkylation in subcritical and supercritical phases [J]. Catalyst Today, 2000, 63(2-4): 223-228.
[55] Okuhara T, Nishimura T, Watanabe H, et al. Catalysis by heteropoly compounds XXI Insoluble heteropoly compounds as highly active catalysts for liquid-phase reactions [J]. Journal of Molecular Catalyst, 1992, 74(1-3): 247-256.
[56] Nishimura T, Okuhara T. Misono M. High catalytic activity of an insoluble acidic cesium salt of dodecatungstophosphoric acid for liquid-phase alkylation [J]. Applied Catalyst. 1991, 73(1): 7-11.
[57]谢文华，杨向光，叶兴凯等．固体杂多酸盐催化性能Ⅰ．磷钨、硅钨杂多碱 金属盐的合成、表征和催化酯化反应[J]．应用化学，1996，13(2)：37-40．
[58]谢文华，杨向光，叶兴凯等．固体杂多酸盐催化性能的研究Ⅱ．磷钨、硅钨 杂多酸的合成、表征和在叔丁醇脱水反应中的催化性能[J]．化学研究与应 用，1996，8(4)：525-530．
[59]肖慎修，杨胜勇，陈天朗等．中心原子对Keggin结构杂多阴离子的电子 结构和催化性质的影响[J]．化学学报，1997，55：356-362．
[60]王力耕，杨兆柱，胡长文等．杂多化合物的理论研究进展[J]．东北师大学 报自然科学版，1998，2：112-120．
[61]胡长文，高丽娟，王恩波等．钨系Keggin结构杂多酸的酸强度及催化反 应特性[J]．东北师大学报自然科学版，1995，2：62-70．
[62]赵忠奎，李宗石，王桂茹等．杂多酸催化剂及其在精细化学品合成中的应 用[J]．化学进展，2004，16(4)：620-630．
[63] Lijima S. Helical microtubules of graphitic carbon [J]. Nature, 1991, 354:56-58.
[64] Philippe S, Massimiliano C, Philippe K. Carbon nanotubes and nanofubers incatalysis [J]. Applied Catalysis A:General, 2003, 253: 337-358.
[65]张延琪，沈玲，李永红等．磷钨酸／多壁碳纳米管催化合成乙酸正丁酯[J]．化 学试剂，2006，28(4)：247-253．
[66]于华荣，成荣明，徐学诚等．碳纳米管负载纳米Fe_2O_3的研究[J]．无机化 学学报，2005，21(11)：1649-1655．
[67]张登松，代凯，方建慧等．碳纳米管改性处理的研究[J]．化工矿物与加工， 2004，3：18-21．
[68] Suresh M K, Shanbhaga G V, Lefebvreb F. et al. Heteropoly acid supported on titania as solid acid catalyst in alkylation of p-cresol with tert-butanol [J]. Journal of Molecular Catalysis A: Chemical. 2006. 256: 324-334.
[69] Edwards J C. Thiel C Y. Brian, et al. Solid-state NMR and FT-IR investigation of 12-tungstophosphoric acid on TiO_2 [J]. Catalysis Letters, 1998, 51: 77-83.
[70]冯长根，樊国栎，王亚军．含铈氧化物储氧材料的合成方法研究进展[J]．现??代化工，2004，24(11)：10-14．
[71] Alessandro Trovarelli, Carla de Leitenburg, Marta Boaro, et al. The utilization of ceria in industrial catalysis [J]. Catalysis Today, 1999, 50: 353-367.
[72]蒋晓原，周仁贤，陈煜等．CuO在Ce_(0．5)Zr_(0．5)O_2上的分散状态及其CO氧 化性能的研究[J]．浙江大学学报(理学版)，2001，28(6)：653-658．
[73] Miguel A G, Thomas S, Veronique P, et al. Selective reduction of NO_x by liquid hydrocarbons with supported HPW-metal catalysts [J]. Catalyst Today. 2007,119:52-58.
[74] Miguel A G, Thomas S, Veronique P, et al. Multifunctional catalysts for de-NO_x processes: The case of H_3PW_(12)O_(40)·6H_2O metal supported on mixed oxides[J]. Applied Catalysis B: Environmental, 2007, 70, 151-159.
[75] Rao G R, Fornasiero P, Monte R D. et al. Reduction of NO over Partially Reduced Metal-Loaded CeO2-ZrO2 Solid Solutions [J]. Journal of catalysis. 1996, 162: 1-9.
[76] Mukaia S R, Mitsutaka S, Litsu L A, et al. Improvement of the preparation method of "ship-in-the-bottle" type 12-molybdophosphoric acid encaged Y-type zeolite catalysts[J]. Applied Catalysis A: General, 2003, 256: 107-113.
[77] Mukaia S R, Takao M, Isao O, et al. Preparation of encaged heteropoly acid catalyst by synthesizing 12-molybdophosphoric acid in the supercages of Y-type zeolite [J]. Applied Catalysis A: General, 1997, 165: 219-226.
[78]梁学正，高珊，杨建国等．HY分子筛催化1，3苯并二茂烷类化合物合成 的研究[J]．化学通报，2006，6：410-414．
[79]尉东光，周敬来，张碧江．HZSM-5的水热脱铝研究[J]．燃料化学学报， 1996，24(2)：103-107．
[80] Claude R D, Michel F, Raymonde F. Vibrational Investigations of Polyoxometalates [J]. Inorganic Chemistry, 1983, 22(2): 207-216.
[81] M. Richter, H. Berndt, R. Eckelt, et al. Zeolite-mediated removal of NO_x by NH_3 from exhaust streams at low temperatures [J]. Catalyst Today, 1999. 54:531-545.
[82] Shigapow N A, Graham W G McCabe W R. et al. The Preparation of??High-surface-area Cordierite Monolith by Acid Reatment [J]. Applied Catalysis A, 1999,182: 137-146.
[83]王建梅，王榕，林建新等．载体的酸处理条件对整体式钌-堇青石催化剂 性能的影响[J]．福州大学学报，2006，34(6)：898-903．
[84]王新平，叶兴凯，吴越．杂多酸在活性炭表面含氧基团上的化学键和作用 [J]．物理化学学报，1995，11(12)：1105-1109．
[85]张晓光，祁建权．活性白土活化工艺及性能的研究[J]．石油化工应用，2006， 25(6)：21-23．
[86]葛旭升，李海花，涂华民．活性白土负载型固体酸催化剂催化酯化性能研 究[J]．保定师范专科学校学报，2006，19(4)：26-28．
[87] Hodjati S,Vaezzadeh C P, Petit C, et al. The machanism of the selective NO_xsorption on H_3PW_(12)O_(40)·6H_2O [J]. Topics in Catalysis, 2001, 16/17(1-4):151-155.
[88] R. Belanger, J.B. Moffat. The interaction of nitrogen oxides with metal-oxygencluster compounds (heteropoly oxometalates) [J]. Journal of molecularcatalysis A: chemical, 1996, 114: 319-329.
[89] Andrew M.H, Robert L.M. In Situ Infrared of the adsorption of nitric oxide by12-tungstophosphoric acid [J]. Journal of physical chemistry, 1998, 102:3175-3184.
[2]赵惠富．污染气体NO_x的形成和控制[M]．科学出版社，1993．
[3]许春丽，李保新．日本大气污染控制对策及现状[J]．环境科学动态，2001， 3：33-36．
[4]李玉江，吴涛．德国燃煤电厂氮氧化物的控制技术[J]．环境科学研究，2000， 13(4)：47-49．
[5]李恒远．中国能源环保与政策法规[J]．环境与科学，2001，10：24-25．
[6] Koebel M, Madia G, Elsener M. Selective catalytic reduction of NO and NO_2 at low temperature [J]. Catalysis Today, 2002, 73: 239-247.
[7] An W Z, Zhang Q L, Chuang K T, et al. A hydrophobic Pt-Fluorinate carbon catalyst for reaction of NO with NH_3 [J]. Industrial & Engineering Chemistry Research, 2002, 41: 27-31.
[8]朱景利，张金昌，马润宇等．改性贵金属催化剂催化还原脱除NO[J]．坏 境科学，2006，27(8)：1508-1511．
[9] Burch R, Coleman M D. An investigation of the NO/H_2/O_2 reaction on noble-metal catalysts at low temperatures under lean-burn conditions [J]. Applied Catalysis B: Environmental, 1999, 23: 115-121.
[10] Garcia-Cortes J M, Perez-Ramirez J, Illan-Gomez M J, et al. Comparative study of Pt-based catalysts on different supports in the low-temperature de-NO_x-SCR with propane [J]. Applied Catalysis B: Environmental, 2001, 30: 399-408.
[11] Roberge D, Anuj R, Kaliaguine S, et al. Selective catalytic reduction of NO under ambient conditions using ammonia as reducing agent and MFI zeolites as catalysts [J]. Applied Catalysis B: Environmental, 1996, 10(4): 237-243.
[12] Richter M. Eckelt R, Parlitz B, et al. Low-temperature conversion of NO_x to N_2 by zeolite-fixed ammonium ions[J]. Applied Catalysis B: Environmental. 1998, 15: 129-146.
[13] Richter M, Trunschke A. Bentrup U, et al. Selective catalytic reduction of nitric oxide by ammonia over egg-shell MnO_x/NaY composite catalysts [J]. Journal of Catalysis, 2002, 206: 98-113.
[14]朱华清，王建国，关春梅．NH_4β分子筛上NO的低温催化还原[J]．燃料 化学学报，2001，29(S)：63-65．
[15]张强，许世森，王志强．选择性催化还原烟气脱硝进展及工程应用[J]．热 力发电，2004，(4)：1-7．
[16] Kapteijn F, Singoredjo L, Andreini A, et al. Activity and selectivity of pure manganese oxides in the selective catalytic reduction of nitric oxide with ammonia [J]. Applied Catalysis B: Environmental. 1994, 3(223): 173-189.
[17] Kijlstra W S, Brands D S, Smit H I, et al. Mechanism of the selective catalytic reduction of NO with NH_3 over MnO_x/Al_2O_3[J]. Journal of Catalysis, 1997. 171:219-230.
[18]伍斌，童志权，黄妍．MnO_2／NaY催化剂上NH_3低温选择催化还原NO_x[J]．石 油化工，2006，35(2)：178-182．
[19] Qi G, Yang R T, Chang R. MnO_x-CeO_2 mixed oxides prepared by co-precipitation for selective catalytic reduction of NO with NH_3 at low temperature [J]. Applied Catalysis B: Environmental, 2004, 51(2): 93-106.
[20]唐晓龙，郝吉明，徐文国等．新型MnO_x催化剂用于低温NH_3选择性催化 还NO[J]．催化学报，2006，27(10)：843-848．
[21]唐晓龙，郝吉明，徐文国等．低温条件下Nano-MnO_x上NH_3选择性催化 还原NO[J]．环境科学，2007，28(2)：289-294．
[22] Lázaro M J, Gálvez M E, Suelves I, et al. Low cost catalytic for NO_xreduction.3.NO reduction tests using NH_3 as reducing agent [J]. Fuel, 2004. 83:875-884.
[23] Yoshikawa M, Yasutake A, Mochida I. Low-temperature selective catalyticreduction of NO_x by metal oxides supported on active carbon fibers [J].Applied Catalysis A: General. 1998, 73: 239-245.
[24]杨超，张俊丰，童志权等．活性炭低温催化还原NO_x影响因素及反应机理??分析[J]．环境科学研究，2006，19(4)：86-90．
[25] Huang B C. Huang R, Jin D J et al. Low temperature SCR of NO with NH_3 over carbon nanotubes supported vanadium oxides [J]. Catalysis Today, 2007. 126 (3-4): 279-283.
[26]胡长文，高丽娟，王恩波等．钨系Keggin结构杂多酸的酸强度及催化反 应特性[J]．东北师大学报自然科学版，1995，2：62-70．
[27]王恩波，胡长文，许林．多酸化学导论[M]．北京：化学工业出版社，1998： 171-172．
[28] Yang R T, Chen N. A new approach to decomposition of nitric oxide usingsorbent/catalyst without reducing gas:use of heteropoly compounds [J]. Ind.Eng. Chem. Res, 1994, 33: 825-831.
[29] Chen N, Yang R T. Activation of nitric oxide by heteropoly compounds:structure of nitric-oxide linkages in tungstophosphoric acid with Keggin units[J].Journal of Catalysis, 1995, 157:76-86.
[30] Belanger R, Moffat J B. A comparative study of adsorption and reaction ofnitrogen oxides on 12-tungstophoric, 12-tungstosilicic, and12-molybdophosphoric acid [J]. Journal of Catalysis, 1995, 152: 179-188.
[31] Kozhevnikova E F, Kozhevnikov I .V. Calorimetric study of the acidity ofbulk and silica-supported heteropoly acid H_3PW_(12)O_(40) [J]. Journal of Catalysis.224(1): 164-169,2004.
[32] Belanger R, Moffat J B. The sorption and reduction of nitrogen oxides by12-tungstophoric and its ammonium salt [J]. Catalysis Today, 1998. 40:297-306.
[33] Andrew M. Herring, Robert L, et al. A Comparison of the Interaction of NitricOxide with the Heteropolytungstic Acids H_3PW_(12)O_(40), H_(0.5)Cs_(2.5)PW_(12)O_(40).HMgPW_(12)O_(40), HgSiW_(11)O_(38), H_4SiW_(12)O_(40), and H_(10)CoW_(12)O_(42)[J]. Journal ofPhysical Chemistry B: 2000. 104: 4653-4660.
[34] Hodjati S, Petit C. Removal of NO_x from a lean exhaust gas by adsorption onheteropoly acids reversible sorption of nitrogen oxides in H_3PW_(12)O_(40)·6H_2O [J].Journal of Catalysis. 2001, 197: 324-334.
[35] Belanger R, Moffat J B. A self-contained catalyst for the reduction of NO_2 [J]. Applied Catalysis B: Environmental, 1997, 13: 167-173.
[36]吴越，叶兴凯，杨向光等．杂多酸的固载化-关于制备负载型酸催化剂的一 般原理[J]．分子催化，1998，10(4)：299-315．
[37] Chu W L, Yang X G, Ye X K. et al. Adsorption of PMo_(12) and SiMo_(12) onActivated Carbon in Aqueous and Acidic Media [J]. Langmuir, 1996, 12(17):4185-4189.
[38] Robert L M, Sukrithirra K B, Andrew M, et al. In situ IR and temperatureprogrammed desorption-mass spectrometry study of NO adsorption anddecomposition by silica supported 12-tungstophosphoric acid [J]. CatalysisToday, 1998,42: 145-157.
[39] Zhang Zh L, Zhu L L, Ma J, et al. Temperature programmed desorption-massNO desorption by HPW [J] React. Kinet. Catal. Lett, 2002, 76(1): 93-101.
[40] Damyanova S, Fierro J L G. Surface properties of titania-supported12-molybdsphoric acid hydrodesulphurization catalysts [J]. Applied CatalysisA: General, 1996, 144: 59-77.
[41] Thomas S, Vaezzadeh K, Pitchon V. Supported heteropolyacids for NO_xstorage and reduction [J]. Topics in Catalysis, 2004, 30/31: 207-213.
[42] Miguel Angel G, Veronique Pitchon, Alain Kiennemann. Storage and reductionof lean-NO_x by using H_3PW_(12)O_(40)·6H_2Osupported on Ti_xZr_(1-x)O_4 [J]. CatalysisToday. 2005, 107-108:60-67.
[43] Miguel Angel G, Veronique Pitchon, Alain Kiennemann. Removal of NO_x fromlean exhaust gas by storage-reduction on H_3PW_(12)O_(40)·6H_2O supported onCe_xZr_(4-x)O_8 [J]. Environ. Sci. Technol. 2005. 39: 638-644.
[44] Damyanova S,Pimitrov L.MariscalR, et al. Immobilization of12-molybdophosphoric and 12-tungstophosphoric acids on metal-substitutedhexagonal mesoporous silica [J]. Applied Catalysis A: General, 2003, 256(1/2): 183-197.
[45] Vaezzadeh K, Petit C, Pitchon V, et al. A new concept for the removal of NO_xfrom a lean exhaust gas using storage on H_3PW_(12)O_(40)·6H_2O. a very fast??desorption and a reduction over a TWC [J]. Catalysis Communications, 2002. 3: 179-183.
[46]王睿，吴丹，赵大传等．实现NO_x吸附分解的杂多化合物催化新体系研究 [J]．现代化工，2006，26(S2)：120-123．
[47]刘俊峰．硅钼杂多酸合成工艺研究[J]．无机盐工业，2001，33(6)：12-13．
[48]张波，付湘清，张汉鹏等．介孔分子筛固载Keggin结构钼钨磷杂多酸的 制备及表征[J]．化学世界，2002，5：230-233．
[49]金明善，翁永根，董和泉等．改性杂多酸催化剂的制备及其在甲缩醛合成 中的催化活性[J]．复旦学报(自然科学版)，2003，42(3)：280-285．
[50] George A, Tsigdinos. Preparation and Characterization of 12-Molybdophosphoric and 12-Molybdosilicic Acids and Their Metal Salts [J]. Ind. Eng. Chem, 1974,13(4):1185-1197 .
[51]余新武，周锦华，陈维莉等．过渡金属杂多钨酸盐的合成、表征及抗结核 病菌活性[J]．湖北师范学院学报，2001，21(4)：11-14．
[52]苏占华，徐学勤，马慧媛等．过渡金属取代的钨铝杂多配合物的制备、表 征和性质[J]．无机化学学报，2005，21(5)：647-652．
[53] Linda C J, Hellmut G K, Evgenya V. A microcalorimetric investigation of heteropolyacids [J]. Microporous matericals, 1993,1(5): 313-322.
[54] Gayraud P Y, Stewart I H, Derouane A H S B, et al. Performance of potassium 12-tungstophosphoric salts as catalysts for isobutane/butene alkylation in subcritical and supercritical phases [J]. Catalyst Today, 2000, 63(2-4): 223-228.
[55] Okuhara T, Nishimura T, Watanabe H, et al. Catalysis by heteropoly compounds XXI Insoluble heteropoly compounds as highly active catalysts for liquid-phase reactions [J]. Journal of Molecular Catalyst, 1992, 74(1-3): 247-256.
[56] Nishimura T, Okuhara T. Misono M. High catalytic activity of an insoluble acidic cesium salt of dodecatungstophosphoric acid for liquid-phase alkylation [J]. Applied Catalyst. 1991, 73(1): 7-11.
[57]谢文华，杨向光，叶兴凯等．固体杂多酸盐催化性能Ⅰ．磷钨、硅钨杂多碱 金属盐的合成、表征和催化酯化反应[J]．应用化学，1996，13(2)：37-40．
[58]谢文华，杨向光，叶兴凯等．固体杂多酸盐催化性能的研究Ⅱ．磷钨、硅钨 杂多酸的合成、表征和在叔丁醇脱水反应中的催化性能[J]．化学研究与应 用，1996，8(4)：525-530．
[59]肖慎修，杨胜勇，陈天朗等．中心原子对Keggin结构杂多阴离子的电子 结构和催化性质的影响[J]．化学学报，1997，55：356-362．
[60]王力耕，杨兆柱，胡长文等．杂多化合物的理论研究进展[J]．东北师大学 报自然科学版，1998，2：112-120．
[61]胡长文，高丽娟，王恩波等．钨系Keggin结构杂多酸的酸强度及催化反 应特性[J]．东北师大学报自然科学版，1995，2：62-70．
[62]赵忠奎，李宗石，王桂茹等．杂多酸催化剂及其在精细化学品合成中的应 用[J]．化学进展，2004，16(4)：620-630．
[63] Lijima S. Helical microtubules of graphitic carbon [J]. Nature, 1991, 354:56-58.
[64] Philippe S, Massimiliano C, Philippe K. Carbon nanotubes and nanofubers incatalysis [J]. Applied Catalysis A:General, 2003, 253: 337-358.
[65]张延琪，沈玲，李永红等．磷钨酸／多壁碳纳米管催化合成乙酸正丁酯[J]．化 学试剂，2006，28(4)：247-253．
[66]于华荣，成荣明，徐学诚等．碳纳米管负载纳米Fe_2O_3的研究[J]．无机化 学学报，2005，21(11)：1649-1655．
[67]张登松，代凯，方建慧等．碳纳米管改性处理的研究[J]．化工矿物与加工， 2004，3：18-21．
[68] Suresh M K, Shanbhaga G V, Lefebvreb F. et al. Heteropoly acid supported on titania as solid acid catalyst in alkylation of p-cresol with tert-butanol [J]. Journal of Molecular Catalysis A: Chemical. 2006. 256: 324-334.
[69] Edwards J C. Thiel C Y. Brian, et al. Solid-state NMR and FT-IR investigation of 12-tungstophosphoric acid on TiO_2 [J]. Catalysis Letters, 1998, 51: 77-83.
[70]冯长根，樊国栎，王亚军．含铈氧化物储氧材料的合成方法研究进展[J]．现??代化工，2004，24(11)：10-14．
[71] Alessandro Trovarelli, Carla de Leitenburg, Marta Boaro, et al. The utilization of ceria in industrial catalysis [J]. Catalysis Today, 1999, 50: 353-367.
[72]蒋晓原，周仁贤，陈煜等．CuO在Ce_(0．5)Zr_(0．5)O_2上的分散状态及其CO氧 化性能的研究[J]．浙江大学学报(理学版)，2001，28(6)：653-658．
[73] Miguel A G, Thomas S, Veronique P, et al. Selective reduction of NO_x by liquid hydrocarbons with supported HPW-metal catalysts [J]. Catalyst Today. 2007,119:52-58.
[74] Miguel A G, Thomas S, Veronique P, et al. Multifunctional catalysts for de-NO_x processes: The case of H_3PW_(12)O_(40)·6H_2O metal supported on mixed oxides[J]. Applied Catalysis B: Environmental, 2007, 70, 151-159.
[75] Rao G R, Fornasiero P, Monte R D. et al. Reduction of NO over Partially Reduced Metal-Loaded CeO2-ZrO2 Solid Solutions [J]. Journal of catalysis. 1996, 162: 1-9.
[76] Mukaia S R, Mitsutaka S, Litsu L A, et al. Improvement of the preparation method of "ship-in-the-bottle" type 12-molybdophosphoric acid encaged Y-type zeolite catalysts[J]. Applied Catalysis A: General, 2003, 256: 107-113.
[77] Mukaia S R, Takao M, Isao O, et al. Preparation of encaged heteropoly acid catalyst by synthesizing 12-molybdophosphoric acid in the supercages of Y-type zeolite [J]. Applied Catalysis A: General, 1997, 165: 219-226.
[78]梁学正，高珊，杨建国等．HY分子筛催化1，3苯并二茂烷类化合物合成 的研究[J]．化学通报，2006，6：410-414．
[79]尉东光，周敬来，张碧江．HZSM-5的水热脱铝研究[J]．燃料化学学报， 1996，24(2)：103-107．
[80] Claude R D, Michel F, Raymonde F. Vibrational Investigations of Polyoxometalates [J]. Inorganic Chemistry, 1983, 22(2): 207-216.
[81] M. Richter, H. Berndt, R. Eckelt, et al. Zeolite-mediated removal of NO_x by NH_3 from exhaust streams at low temperatures [J]. Catalyst Today, 1999. 54:531-545.
[82] Shigapow N A, Graham W G McCabe W R. et al. The Preparation of??High-surface-area Cordierite Monolith by Acid Reatment [J]. Applied Catalysis A, 1999,182: 137-146.
[83]王建梅，王榕，林建新等．载体的酸处理条件对整体式钌-堇青石催化剂 性能的影响[J]．福州大学学报，2006，34(6)：898-903．
[84]王新平，叶兴凯，吴越．杂多酸在活性炭表面含氧基团上的化学键和作用 [J]．物理化学学报，1995，11(12)：1105-1109．
[85]张晓光，祁建权．活性白土活化工艺及性能的研究[J]．石油化工应用，2006， 25(6)：21-23．
[86]葛旭升，李海花，涂华民．活性白土负载型固体酸催化剂催化酯化性能研 究[J]．保定师范专科学校学报，2006，19(4)：26-28．
[87] Hodjati S,Vaezzadeh C P, Petit C, et al. The machanism of the selective NO_xsorption on H_3PW_(12)O_(40)·6H_2O [J]. Topics in Catalysis, 2001, 16/17(1-4):151-155.
[88] R. Belanger, J.B. Moffat. The interaction of nitrogen oxides with metal-oxygencluster compounds (heteropoly oxometalates) [J]. Journal of molecularcatalysis A: chemical, 1996, 114: 319-329.
[89] Andrew M.H, Robert L.M. In Situ Infrared of the adsorption of nitric oxide by12-tungstophosphoric acid [J]. Journal of physical chemistry, 1998, 102:3175-3184.