Development of porous nano-structured materials with heterojunction structure and application to low temperature de-NOx catalysts

异质结多孔纳米结构材料的研制及其在低温脱硝催化剂中的应用

• 批准号: 15360432
• 负责人: MACHIDA Masato
• 金额: $ 4.29万
• 依托单位: Kumamoto University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2003
• 资助国家: 日本
• 起止时间: 2003 至 2004
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-15360432/
• 关键词: NO_x; heterojunction; porous material; metal oxide; catalyst; electrolysis; deNOx process; selective reduction; ヘテロ接合; ナノ複合体; 貴金属

The anion exchange property of hydrotalcite(HT),Mg_<0.74>Al_<0.26>(OH)_2(NO_3)_<0.26>, was studied for the preparation of porous catalysts containing highly dispersed noble metals. In the anion exchange using complexes, PtCl_6^<2-> and PdCl_4^<2->, partial replacement of the ligand with NO_3^- in the HT interlayer occurred as was revealed by XAFS analysis. On heating in a H_2 flow, the nitrate ligand would be reduced to evolve N_2 and the vacant site thus formed can subsequently be occupied by NO_3^- in the interlayer. Such a catalytic role of interlayer noble metals facilitates the removal of NO_3^- from the interlayer space and thus converts the layered structure into a porous framework. The Pt-HT catalyst allowed 82% NO_x conversion at 70℃, whereas a supported Pt/MgO required higher temperature 90℃ where 87% NO_x conversion was obtained. Similarly, Pd-HT catalyst allowed higher NO_x conversion at the lower temperature compared with a supported Pd/MgO catalyst. Thus, Pt-HT nanocompos … More ites were found to be active for the low temperature NO-H_2 reaction in the presence of excess O_2.On the other hand, the reduction of NO to N_2/N_2O in the presence of excess O_2 has been successfully achieved at 70℃ using an electrochemical cell of the type,0.1% NO,0-10% O_2,Pt |NAFION| Pt,H_2O. An H^+-conducting solid polymer electrolyte(SPE) plays a key role in evolving hydrogen on the Pt cathode, where the catalytic NO-H_2 takes place. It was revealed that the competitive H_2-O_2 reaction is suppressed because the Pt surface was covered with stable nitrate(NO_3) species, which blocks oxygen adsorption hereon. The inhibition of H_2-O_2 reaction becomes most efficient at 【less than or equal】100℃ in agreement with the optimal operation temperature range of SPE. The reduction efficiency of NO in an excess O_2 could be improved by packing 1 wt% Pt/ZSM-5 catalyst in the cathode room. The combination between the SPE cell and Pt catalysts can broadly be applied to novel low-temperature deNOx processes in a strongly oxidizing atmosphere. Less

研究了Hydrotalcite（HT），Mg_ <0.74> Al_ <0.26>（OH）_2（NO_3）_ <0.26>的阴离子交换特性，用于制备含有高度分散贵族金属的多孔催化剂。在使用复合物的阴离子交换中，ptcl_6^<2->和pdcl_4^<2->，在ht Interlayer中，将配体的部分替换为XAFS分析所示。在H_2流中加热时，硝酸盐配体将减小为Evolution N_2，因此形成的空置位点随后可以被夹层中的NO_3^ - 占据。层间金属的这种催化作用有助于从层间空间中移除NO_3^，因此将分层结构转换为多孔框架。 PT-HT催化剂允许在70℃时进行82％的NO_X转换，而受支持的PT/MGO需要更高的温度90℃，其中获得了87％的NO_X转换。同样，与受支持的PD/MGO催化剂相比，PD-HT催化剂可以在较低的温度下较高的NO_X转换。这是PT-HT纳米复合物…在过量O_2的存在下，发现更多的物品在低温NO-H_2反应中有效，在存在过多的O_2的情况下，NO至N_2/N_2O的降低是在70时成功实现的，使用了70 the，使用类型的0.1％No，0.1％，0-10％O__2，PT PT，H_2O。 H^+ - 进行固体聚合物电解质（SPE）在在发生催化NO-H_2的Pt阴极上进化的氢中起关键作用。据显示，竞争性的H_2-O_2反应被抑制，因为Pt表面被稳定的硝酸盐（NO_3）物种覆盖，该物种阻止了此类的氧气吸附。 H_2-O_2反应的抑制作用在[小于或等于] 100℃时与SPE的最佳操作温度范围一致。通过将1 wt％PT/ZSM-5催化剂包装在阴极室中，可以提高多余O_2中NO的降低效率。 SPE细胞和PT催化剂之间的组合可以广泛地应用于强烈氧化的大气中的新型低温DENOX过程。较少的

项目成果

Extremely Large NOx Sorption onto Inorganic Porous Materials in the Presence of Water Vapor

水蒸气存在下无机多孔材料对大量氮氧化物的吸附

• 发表时间: 2004
• 期刊: Proceedings of International Japan-Korea Seminar on Ceramics
• 作者: K.Ito;M.Takenami;K.Ikeue;M.Machida
• 通讯作者: M.Machida

Synthesis and Structure of Pt/hydrotalcite Nanocomposites for Catalytic NO-H_2-O_2 Reactions at Ambient Temperatures

常温催化NO-H_2-O_2反应的Pt/水滑石纳米复合材料的合成与结构

• 发表时间: 2004
• 期刊: Proceedings of International Korea-Japan Seminar on Ceramics
• 作者: S.Hamada;K.Ikeue;M.Machida
• 通讯作者: M.Machida

Formation of Porous Structure via Catalytically Promoted Decomposition of Hydrotalcites Intercalating Hexachloroplatinate

水滑石插层六氯铂酸盐催化促进分解形成多孔结构

• 发表时间: 2004
• 期刊: Solid State Ionics Vol.172, No.1-4
• 作者: S.Hamada;M.Machida
• 通讯作者: M.Machida

The Role of Spillover on NO-H_2 reaction over Pd Catalyst Supported on NO_x-Adsorbing Material, MnO_x-CeO_2

NO_x吸附材料MnO_x-CeO_2负载Pd催化剂上溢出对NO-H_2反应的影响

• 发表时间: 2003
• 期刊: Journal of Physical Chemistry B 107
• 作者: M.Machida;D.Kurogi;T.Kijima
• 通讯作者: T.Kijima

Selective NO-H_2-O_2 Reactions over Pt/TiO_2-ZrO_2 at 【less than or equal】100℃

【小于等于】100℃ Pt/TiO_2-ZrO_2上选择性NO-H_2-O_2反应

• 发表时间: 2003
• 期刊: Studies in Surface Science and Catalysis 145
• 作者: M.Machida;S.Ikeda;T.Kijima
• 通讯作者: T.Kijima