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ZrO2-TiO2-CeO2的制备及其在NH3选择性催化还原NO中的应用 总被引:1,自引:0,他引:1
采用共沉淀法制备了载体材料TiO2、ZrO2-TiO2及ZrO2-TiO2-CeO2, 并利用X射线衍射(XRD)实验、比表面积测定(BET)、程序升温脱附(NH3-TPD)、储氧性能测定(OSC)及程序升温还原(H2-TPR)等方法对三种载体材料进行了表征. 结果表明, ZrO2-TiO2-CeO2具有较多的表面强酸位, 并具有一定的储氧性能和较强的氧化还原性能. 以三种材料为载体, 制备了质量分数分别为1%、9%的V2O5、WO3的整体式催化剂. 研究了三种催化剂在富氧条件下用NH3选择性催化还原NO的催化性能. 结果表明, 以ZrO2-TiO2-CeO2为载体的催化剂在反应空速为10000 h-1, 275 ℃时, NO的转化率接近100%, 具有最好的催化活性,并有良好的应用前景。 相似文献
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Yiseul Yoo Giseung Lee Min-Gi Jeong Hun-Gi Jung Sunghee Shin Dongjin Byun Taeeun Yim Hee-Dae Lim 《Journal of Energy Chemistry》2022,(2):646-653
Regulation of the Li2CO3 byproduct is the most critical challenge in the field of non-aqueous Li–O2 batteries.Although considerable efforts have been devoted to preventing Li2CO3 formation,no approaches have suggested the ultimate solution of utilizing the clean Li2O2 reaction instead of that of Li2CO3.Even if extremely pure O2 is used in a Li–O2 cell,its complete elimination is impossible,eventually generating CO2 gas during charge.In this paper,we present the new concept of a CO2-adsorbent spongy electrode(CASE),which is designed to trap the evolved CO2 using adsorption materials.Various candidates composed of amine functional groups(–NH2)for capturing CO2 were screened,with quadrapurebenzylamine(QPBZA)exhibiting superior CO2-adsorbing ability among the proposed candidates.Accordingly,we fabricated the CASE by sandwiching QPBZA between porous carbon layers,which facilitated the transport of gaseous products.The new electrode was demonstrated to effectively capture the evolved CO2 during charge,therefore altering the reaction pathways to the ideal case.It is highly advantageous to mitigate the undesirable CO2 incorporation in the next discharge,resulting in improved cyclability.This novel concept of a CO2-sponging electrode provides an alternative route to the realization of practically meaningful Li–O2 batteries. 相似文献
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制备Ti/SnO2+Sb2O4/PbO2电极,电极的组分及其价态由XRD和XPS表征;该电极可将2,2-二羟甲基丙醛直接电合成2,2-二羟甲基丙酸.应用高效液相色谱分析原料和产物,电化学方法研究电合成影响因素,包括:2,2-二羟甲基丙醛浓度、溶液pH值、反应温度和氧化电位等.在优化条件下(pH=1,C醛=0.10 mol.L-1,t=15℃,E=1.8 V)电合成2,2-二羟甲基丙酸的转化率为58%,选择性36%,电流效率28%.本法为该产物的合成提供了一种新的途径. 相似文献
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采用溶胶 -凝胶法制备了 Ti O2 / Si O2 和不同浓度 Fe3 掺杂的 Fe3 / Ti O2 / Si O2 复合纳米粉末 ,并利用XRD、BET、UV-vis等手段研究了 Ti O2 / Si O2 及掺铁形成的 Fe3 / Ti O2 / Si O2 复合微粒的表面结构形态变化 ,以及对污染物 NO- 2 光催化降解的影响 .结果表明 ,Fe3 / Ti O2 / Si O2 (ω( Fe3 ) =1 .5 % ,m( Ti)∶ m( Si) =2∶ 1 )具有最佳活性 ,样品呈晶化度较低的锐钛矿结构 .Fe3 掺杂导致晶粒的增大 ,稳定性降低 ,大大提高了半导体的光催化活性 ,有利于对低浓度 NO- 2 的光催化降解 相似文献
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以SrCO3,Si3N4,Eu2O3为原料,在N2气氛下,采用自还原高温固相法制备了SrSi2O2N2:Eu2+荧光粉.研究了该荧光粉的物相结构、发光性能和晶体形貌,同时对比在不同气氛下合成的荧光粉.结果表明,在N2气氛与N2/H2气氛下分别合成的SrSi2O2N2:Eu2+荧光粉物相结构和光谱特性基本一致.显示出合成了主晶相SrSi2O2N2,但还含有少量未知的中间项.Eu2+浓度的变化不影响激发状态,而发射光谱的波长在Eu2+浓度为l mol%~20mol%之间,从530 nm的绿光红移至550 nm的黄绿光区域.同时,激发光谱覆盖的范围宽,均能有效的被UV或蓝光激发,这意味着该类荧光粉在白光LED方面有可能得到广泛的应用. 相似文献
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采用共沉淀法制备了TiO_2、TiZr和TiSn载体,浸渍锰制备了10%MnO_2的MnTi、MnTiZr和MnTiSn催化剂。采用BET、XRD、H_2-TPR、FT-IR和XPS等对样品进行表征,并对三种催化剂进行固定床脱汞性能实验。结果表明,在100-300℃,MnTiZr和MnTiSn催化剂脱汞性能均优于MnTi催化剂,这归因于Sn和Zr的引入提升了催化剂比表面积和低温氧化还原性能增加了催化剂表面的酸性位点数量、高价态锰离子和O~*含量;在反应温度为150-300℃,MnTiSn催化剂脱汞效率均高于MnTiZr催化剂这是由于前者具有更好的氧化还原性能,表面具有更多含量的高价态锰离子、O~*含量和酸性位点数量;在Hg~0脱除过程中催化剂表面活性组分如高价态锰离子和O~*均消耗,参与了Hg~)氧化为Hg~(2+)的反应且MnTiSn催化剂表面活性组分的消耗量更多。 相似文献
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伴随生产的发展和进步,环境污染物也日益增多,危害人类和植物。主要针对大气污染物中的SO2、Cl2、NO2等气体对植物叶的危害作以常识介绍并给予验证。 相似文献
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Khiari Jameleddine 《Tetrahedron letters》2006,47(17):2973-2975
An alternative preparation of 2-dimethylaminomethylene-1,3-bis(dimethylimonio)propane diperchlorate from malonic acid is described along with its application to the synthesis of 2,4,6-trisubstituted phenols and 2-(N-(2,2-diformylethenyl)amino)pyridine. 相似文献
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双(甲基二茂铁基)代烷羟的合成 总被引:1,自引:0,他引:1
二茂铁衍生物在复合固体火箭推进剂中用作燃速催化剂,但其挥发性和迁移性较大,直接影响储存或使用时导弹的弹导性能。本文报导三种新型燃速催化剂:双(甲基二茂铁基)甲烷,2,2-双(甲基二茂铁基)丙烷和2,2-双(甲基二茂铁基)丁烷的合成和表征。小型试验表明其催化活性、挥发性及迁移性能均优于国内目前使用的叔丁基二茂铁。 相似文献
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E. A. Makarova V. N. Kopranenkov V. K. Shevtsov E. A. Luk'yanets 《Chemistry of Heterocyclic Compounds》1994,30(9):1043-1048
Bromination of tetra(tert-butyl)porphyrazine by N-bromosuccinimide in chloroform results in the formation of mono- and dibromides, substitution for the bromine atoms of which produced the corresponding cyano, phenoxy, phenylthio, styryl, phenylethynyl and piperidino derivatives. From the monobromide and 2,2-bis(p-hydroxyphenyl)propane, the dimeric porphyrazine 2,2-bis[p-tetra(tert-butyl)porphyrazyloxyphenyl]propane was similarly obtained.Scientific Research Institute of Organic Intermediate Products and Dyes, Moscow 103787. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1206–1212, September, 1994. Original article submitted September 6, 1994. 相似文献
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Maleic and citraconic anhydrides were reacted with several diamines to obtain a novel class of high temperature resistant bisimides.1–3 The bisimides were characterized by melting points, elemental analysis, UV–Vis, 1H- and 13C-NMR, and mass spectral analysis. The bisimide monomers were then polymerized by the addition process. A poly(amidemaleimide) was also synthesized by reacting maleic anhydride with p-aminobenzhydrazide. The thermal stability of these highly crosslinked poly(bisimide)s were examined by TGA and DTA. A neat bisimide monomer obtained from 2,2′-bis[4(p-aminophenoxy)phenyl] propane with maleic anhydride namely, 2,2′-bis[4-(p-maleimidophenoxy)phenyl]propane was reacted with 2,2′-bis[4(p-aminophenoxy)phenyl]propane by the Michael reaction.4 A fiber glass cloth reinforced laminate was prepared from bismaleimide and amine mixture and the mechanical properties of the test laminate evaluated. 相似文献
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Vysotskaya O. V. Oparina L. A. Parshina L. N. Gusarova N. K. Trofimov B. A. 《Russian Journal of Organic Chemistry》2002,38(8):1082-1087
Reactions of 2-(vinyloxy)ethyl methacrylate with diols [ethylene glycol, diethylene glycol, triethylene glycol, oligoethylene glycol-400, Z-2-butene-1,4-diol, 2-butyne-1,4-diol, 1,1,3,3-tetramethyl-1,3-bis(3-hydroxypropyl)disiloxane, 2,2-bis(4-hydroxyphenyl)propane] and polyols (glycerol, pentaerythritol) under electrophilic conditions (1 wt% of CF3COOH, 20-60°C, 1-3 h) result in quantitative formation of functional acetal methacrylates. 相似文献
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R. G. Gaughan H. W. Hill J. E. Inda 《Journal of polymer science. Part A, Polymer chemistry》1986,24(3):419-426
Poly[2,2-bis(4-oxycyclohexyl)propane adipate] was formed by melt polymerizing adipic acid and 2,2-bis(4-hydroxycyclohexyl)propane in the presence of n-butylhydroxyoxostannane. This polyester possessed a melting temperature (Tm) of 200°C and a glass transition temperature (Tg) of 75°C. An excellent notched impact strength of 22 ft. lbs./in. was its best physical property. 相似文献
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首先通过Friedel-Crafts酰基化反应得到1,4-双-(4′-溴苯酰基)苯,经两步合成芳香二胺2,2-双-[4-(4-氨基苯氧基)苯基]丙烷,以1,4-双-(4′-溴苯酰基)苯和2,2-双-[4-(4-氨基苯氧基)苯基]丙烷为单体,以三(二亚苄基丙酮)二钯为催化剂,1.1′-联萘-2.2′-二苯膦(BINAP)为配体,由钯催化的胺基化反应缩聚合成了高分子量含异亚丙基聚亚胺醚酮(pr-PIEK),Mn=5.15×104、Mw=1.26×105.其结构由红外、核磁氢谱和元素分析表征,表征结果与目标结构吻合良好.通过XRD、DSC和TG等对pr-PIEK的主要性能进行分析,结果表明pr-PIEK为无定形态,表现出良好的热稳定性(高的热分解温度TD>450℃)、力学性能(拉伸强度为72.76 MPa、拉伸模量为1013.63 MPa、断裂伸长率为10.32%)和较好的溶解性能,pr-PIEK在室温条件下可溶解在普通有机溶剂氯仿中,50℃溶于丙酮. 相似文献
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Kathy C. Chuang Daniel A. Scheiman Joyce Fu Marcus Crawford 《Journal of polymer science. Part A, Polymer chemistry》1999,37(14):2559-2567
Thermoplastic and thermoset polyimides derived from 2,2-bis[4-(4-aminophenoxy)phenyl]propane (BAPP) and 4,4′-bis(4-aminophenoxy)-2,2′-dimethylbiphenyl (BAPD) were prepared and characterized. Their physical and thermal properties as well as the polyelectrolyte effect exhibited by BTDA–BAPP polyamic acids in NMP solution were discussed. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 2559–2567, 1999 相似文献
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I. N. Zyuzin 《Russian Journal of Organic Chemistry》2013,49(5):678-685
Reaction of bis(methoxy- and ethoxy-NNO-azoxy)methane with benzyl halides and alkali under the conditions of a phase-transfer catalysis furnishes in one stage E-1-(alkoxy-NNO-azoxy)-2-arylethene in 21–55% yields. The intermediate products, 1,1-bis(alkoxy-NNO-azoxy)-2-arylethanes under the action of alkali eliminate one of the two alkoxy-NNO-azoxy groups with the formation of a double bond. The optimum solvent is DMSO, and as benzyl halides, benzyl chlorides. In the case of 4-bromobenzyl bromide a formation was found of a side bisbenzylation product, 1,3-bis(4-bromophenyl)-2,2-bis(methoxy-NNO-azoxy)propane. 相似文献