检索结果-南通市图书馆

A Comparison of hydrothermal aging, SO₂ and Propene Poisoning Effects on NH₃-SCR over Cu-ZSM-5 and Cu-SAPO-34 Catalysts

引用

Journal of Materials Science and Chemical Engineering 2024年第5期12卷 10-28页

作者： Kouadio Brou Albert Koffi Konan Martin Zran Van Eric-Simon Horo Kone Unité de Formation et de Recherche des Sciences et de Technologies (UFR ST) Universit&#233 Alassane Ouattara Bouak&#233 C&#244te d&#8217Ivoire Unité de Formation et de Recherche Environnement (UFR E) Universit&#233 Jean Lorougnon Gu&#233d&#233 Daloa C&#244te d&#8217Ivoire Unité de Formation et de Recherche des Sciences des Structures de la Mati&#232re et de Technologie (UFR SSMT) Abidjan C&#244te d&#8217Ivoire

This study was aimed to investigate the effects of hydrothermal aging, propene and SO2 poisoning on the ammonia-selective catalytic reduction (NH3-SCR) performance of both Cu-SAPO-34 and Cu-ZSM-5. The catalytic activities of fresh, aged and poisoned samples were tested in ammonia-selective catalytic reduction (NH3-SCR) of NOx conditions. The XRD, TG and N2-desorption results showed that the structures of the Cu-SAPO-34 and Cu-ZSM-5 remained intact after 750˚C hydrothermally aged, SO2 and propene poisoned. After hydrothermal aging at 750˚C for 12 h, the NO reduction performance of Cu-ZSM-5 was significantly reduced at lower temperatures, while that of Cu-SAPO-34 was less affected. Moreover, Cu-SAPO-34 catalyst showed high NO conversion with SO2 or propene compared to Cu-ZSM-5. However, Cu-ZSM-5 showed a larger drop in catalytic activity with SO2 or propene compared to Cu-SAPO-34 catalyst. The H2-TPR results showed that Cu2 ions could be reduced to Cu and Cu0 for Cu-ZSM-5, while no significant transformation of copper species was observed for Cu-SAPO-34. Meanwhile, the UV-vis DRS results showed that CuO species were formed in Cu-ZSM-5, while little changes were observed for the Cu-SAPO-34. Cu-SAPO-34 showed high sulfur and hydrocarbon poison resistance compared to Cu-ZSM-5. In summary, Cu-SAPO-34 with small-pore zeolite showed higher hydrothermal stability and better hydrocarbon and sulfur poison resistant than Cu-ZSM-5 with medium-pore.

关键词： hydrothermal aging Propene and SO2Poisoning Ammonia-Selective Catalytic Reduction(NH3-SCR) Cu-SAPO-34 Cu-ZSM-5

来源：

维普期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

A comparative study of the thermal and hydrothermal aging effect on Cu-SSZ-13 for the selective catalytic reduction of NOx with NH_(3)

引用

Chinese Journal of Chemical Engineering 2022年第5期35卷 68-77页

作者： Huawang Zhao Xiaomin Wu Zhiwei Huang Ziyi Chen Guohua Jing Department of Environmental Science&Engineering College of Chemical EngineeringHuaqiao UniversityXiamen 361021China

In this work,the characterizations of Cu-SSZ-13 after hydrothermal aging(HTA)and thermal aging(TA)at different temperatures(750,800,and 850°C)are compared,and the differences between those two serious aged samples are analyzed.With this data,the effect of steam on catalysts deactivation during hydrothermal aging is analyzed.The TA at 750 and 800°C causes the dealumination and the agglomeration of Cu^(2+)ions to Cu O,resulting in the activity loss of Cu-SSZ-13.The presence of steam upon HTA at750 and 800°C aggravates the catalyst deactivation by increasing the Al detachment and the Cu^(2+)agglomeration.The structure and cupric state are almost the same in the Cu-SSZ-13 after TA and HTA at 850°C,respectively,indicating that the steam has little influence on the deactivation.The formation of CuAl_(2)O_(4) spinel is the primary reason for the deactivation after both HTA and TA at 850°C,probably attributed to the strong interaction between Cu^(2+)ions and framework Al sites at high temperatures.

关键词： Emission control Selective catalytic reduction Cu-SSZ-13 hydrothermal aging Thermal aging

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Application of silica-alumina as hydrothermally stable supports for Pt catalysts for acid-assisted soot oxidation

引用

Rare Metals 2023年第5期42卷 1614-1623页

作者： Shu-Ran Liu Shu-Ting Luo Xiao-Dong Wu Tao-Jin Wang Rui Ran Duan Weng Zhi-Chun Si Shuang Liu Key Laboratory of Advanced Materials of Ministry of Education of China School of Materials Science and EngineeringTsinghua UniversityBeijing100084China International Graduate School at Shenzhen Tsinghua UniversityShenzhen518055China School of Materials Science and Engineering Ocean University of ChinaQingdao266100China

In this work,silica-alumina mixed oxides with different SiO_(2)contents(5%and 30%)were adopted as acidic supports for platinum catalysts for soot oxidation.The obtained catalysts were hydrothermally aged in 10%H_(2)0/air at 750℃for 20 h.The catalysts were characterized by X-ray diffraction(XRD),N_(2)adsorption,inductively coupled plasma(ICP),CO chemisorption,NH3temperature-programmed desorption(TPD),infrared(IR)spectroscopy of CO adsorption,temperature-programmed oxidation(TPO)of NO,and TPD of NO_(x).The surface acidity of catalyst was positive correlated with the content of SiO_(2),which kept platinum in metallic and partially oxidized states in an oxidizing atmosphere.Compared with sulfation treatment on the alumina support,the application of SiO_(2)-Al_(2)O_(3)mixed oxides does not result in the coverage of Pt active sites and the prepared catalysts exhibit excellent activity for NO oxidation.They promote NOxpreferential adsorption on soot and decomposition of surface oxygenated compounds(SOCs)as the sulfated Pt/Al_(2)O_(3)catalyst does.

关键词： Platinum Acidic support Diesel soot hydrothermal aging

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Effects of baria on propane oxidation activity of Pd/Al2O3 catalyst:Pd–BaO interaction and reaction routes

引用

Progress in Natural Science:Materials International 2014年第5期24卷 280-286页

作者： Min Li Xiaodong Wu Shuang Liu Jie Wan Rui Ran Duan Weng Laboratory of Advanced Materials (MOE) School of Materials Science and Engineering Tsinghua University

The BaO-modified Pd/Al2O3exhibits much better catalytic activity than Pd/Al2O3for C3H8 oxidation both before and after the hydrothermal aging treatment. Further studies ascribe its good activity to the influence of BaO species on the physicochemical characteristics of the catalyst and the reaction routes. Firstly, the BaO species inhibits the phase transformation of alumina, resulting in higher surface area of the catalysts and hereby a better dispersion of Pd. Secondly, the basic nature and electron-withdrawing effect of barium oxide maintain palladium at high oxidation state, which leads to a higher PdO content on surface of the BaO-modified catalyst. Finally, the formation/decomposition of carbonate/bicarbonate species can be promoted by the addition of BaO, which provide extra reaction routes and are important for the deep oxidation of C3H8.

关键词： Pd/Al2O3 C3H8combustion hydrothermal aging BaO modification Surface PdO content

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Effect of Sizing on the Interfacial Shear Strength of Carbon Fiber/Epoxy Resin Monofilament Composite

引用

Journal of Wuhan University of Technology(Materials Science) 2014年第3期29卷 483-487页

作者：杨雨松肇研 LI Ye DONG Qi CHEN Da School of Materials Science and Engineering Beihang University

The single fiber fragmentation test （SFFT） was used to measure the interracial shear strength （IFSS） of sized and unsized CF800/epoxy resin monofilament composite in order to evaluate the effect of sizing respectively. Besides, the interfacial reinforcing mechanism was explored by analyzing the surface morphology of the carbon fibers, the wettability between the carbon fibers and the epoxy resin, and the chemical characteristics of the fiber surface. Moreover, the effect of sizing on heat and humidity resistance of interface was investigated by aging test. The results show that sizing improves IFSS of CF800/epoxy resin monofilament composite by 59% through increasing the functional groups containing oxygen and through enhancing wettability, while after sizing the heat and humidity resistance of interface is decreased.

关键词： interface SFFT sizing hydrothermal aging

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

CO and C3Hs Total Oxidation over Pd Catalysts Supported on Commercial Ce-Zr Solid Solution： Effects of the Calcination Temperature and hydrothermal Treatment

引用

Chemical Research in Chinese Universities 2015年第2期31卷 288-293页

作者： ZHOU Renmei ZHANG Xuanyu LU Jiqing HU Gengshen LUO Mengfei Key Laboratory of the Ministry of Education for Advanced Catalysis Materials Institute of Physical Chemistry Zhejiang Normal University Jinhua 321004 P. R. China

A series of Pd catalysts supported on commercial Ce-Zr solid solution（Pd/CZ） calcined at different tem- peratures（750, 900 and 1050 %℃） was prepared via an incipient wetness impregnation method. The activities of the fresh and hydrothermally aged PdTCZ catalysts were tested for total oxidation of CO and C3H8. For CO oxidation, the activity of either fresh or aged Pd/CZ catalysts decreased with the elevating of calcination temperature of CZ support, with a fresh catalyst calcined at 750 ℃ possessing the highest activity and hydrothermal stability. For C3H8 total oxidation, the activity of Pd/CZ catalysts could be improved by increasing the calcination temperature of support. However, the aged Pd/CZ catalysts showed higher activity than corresponding fresh Pd/CZ catalysts. The turnover frequency（TOF） over Pd/CZ catalyst for CO oxidation increased with increasing reduction ability of the catalysts, with a fresh catalyst calcined at 750 ℃ having the highest value（0.27 s^-1）. However, the TOF of Pd/CZ catalyst for C3Hs total oxidation was mainly affected by the size of Pd particles, and large Pd particles possessed a higher activity, with the highest TOF value（0.96s^-1） obtained over an aged catalyst calcined at 1050 ℃.

关键词： Pd/Ce-Zr catalyst Stability Turnover frequency hydrothermal aging

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

热塑性聚酯的物理老化和化学降解及其相互作用

热塑性聚酯的物理老化和化学降解及其相互作用

引用

2012年全国高分子材料科学与工程研讨会

作者：杜斌杨睿谢续明清华大学化工系高分子研究所

＜正＞热塑性聚酯（以聚对苯二甲酸乙二醇酯（PET）为代表）由于其主链存在的酯基结构而易于水解,因此水热老化对其使用稳定性的影响最为重要。在这个过程中,除了酯基的水解反应外,PET还会发生物理老化-热焓松弛。加上水和温度的作用,PE... 详细信息

＜正＞热塑性聚酯（以聚对苯二甲酸乙二醇酯（PET）为代表）由于其主链存在的酯基结构而易于水解,因此水热老化对其使用稳定性的影响最为重要。在这个过程中,除了酯基的水解反应外,PET还会发生物理老化-热焓松弛。加上水和温度的作用,PET的水热老化是多因素综合作用下的各种物理化学变化的结果（如图1）。本文研究了PET水热老化过程中的水解过

关键词： PET hydrothermal aging physical aging hydrolysis

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：