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基于γ-Al2O3-ZrO2-ThO2的Pd基催化剂载体制备及应用 认领 引用 被引量：2
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作者 张庆 张洪泉 白涛 《实验技术与管理》 CAS 北大核心 2020年第1期56-58,70,共3页
设计了一种用于负载型Pd基催化剂的γ-Al2O3-ZrO2-ThO2纳米管阵列载体。原位生长法制备的纳米孔Al2O3陶瓷模板经化学沉积形成γ-Al2O3-ZrO2-ThO2纳米载体,并以此纳米载体作为活性组分制备了具有高催化氧化活性的Pd催化剂。电镜结果表明... 设计了一种用于负载型Pd基催化剂的γ-Al2O3-ZrO2-ThO2纳米管阵列载体。原位生长法制备的纳米孔Al2O3陶瓷模板经化学沉积形成γ-Al2O3-ZrO2-ThO2纳米载体,并以此纳米载体作为活性组分制备了具有高催化氧化活性的Pd催化剂。电镜结果表明,催化剂组分Pd能够均匀分散于纳米载体中。实验表明采用以γ-Al2O3-ZrO2-ThO2纳米材料为Pd基催化剂载体的CH4传感器具有较好的线性度和快速响应特性。 展开更多
关键词 催化剂载体 纳米管阵列 γ-Al2O3-ZrO2-ThO2
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CaO含量对SiO2-Al2O3-CaO系轻质陶粒性能的影响及机理分析 认领 引用
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作者 张祎欢 范海宏 +2 位作者 李俊杰 王玉浓 吴瑞 《新型建筑材料》 2026年第8期88-93,99,共6页
以煤矸石和垃圾焚烧飞灰等工业固废为主要原料,研究CaO含量(0.53%~33.61%)对SiO2-Al2O3-CaO系轻质陶粒物理性能及矿物组成的影响规律。结果表明,随着CaO含量增加,陶粒表观密度与单颗粒强度呈现减-增-减的非单调变化趋势,膨胀率与吸水率... 以煤矸石和垃圾焚烧飞灰等工业固废为主要原料,研究CaO含量(0.53%~33.61%)对SiO2-Al2O3-CaO系轻质陶粒物理性能及矿物组成的影响规律。结果表明,随着CaO含量增加,陶粒表观密度与单颗粒强度呈现减-增-减的非单调变化趋势,膨胀率与吸水率则呈相反规律。当CaO含量为11.56%、烧结温度1180℃时,可获得综合性能最优的陶粒:单颗粒强度1.75 MPa,表观密度471.43 kg/m3,吸水率3.85%。XRD与SEM-EDS分析表明,钙长石是陶粒膨胀过程的主导晶相,其含量随CaO含量的增加而升高。机理研究表明,适量CaO既可降低熔体黏度促进气体包裹,又能与硅铝组分反应形成钙长石骨架,二者协同作用实现陶粒的轻质化。 展开更多
关键词 SiO2-Al2O3-CaO系 陶粒 工业固废 钙长石 CaO含量 烧结机理
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微纳米添加剂α-Al2O3在表面涂层领域的应用现状及市场前景 认领 引用
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作者 伏建康 杨茂盏 +2 位作者 冉长荣 郭太雄 张千峰 《材料科学》 2025年第3期468-475,共8页
微纳米α-Al2O3是一种重要的功能材料,因其优异的硬度、耐磨性、耐腐蚀性和高热稳定性,在表面涂层领域得到了广泛应用。随着微纳米技术的发展,微纳米级α-Al2O3作为添加剂在各涂层体系中的应用得到了深入研究,显示出其能够显著改善涂层... 微纳米α-Al2O3是一种重要的功能材料,因其优异的硬度、耐磨性、耐腐蚀性和高热稳定性,在表面涂层领域得到了广泛应用。随着微纳米技术的发展,微纳米级α-Al2O3作为添加剂在各涂层体系中的应用得到了深入研究,显示出其能够显著改善涂层性能的潜力。微纳米α-Al2O3颗粒具有较大的比表面积和表面活性,能够增强涂层的机械性能,如硬度和耐磨性,同时提高涂层的耐腐蚀性和耐高温性能。微纳米α-Al2O3也是一种极优良的改性材料,其与有机硅烷、树脂等材料复合改性,既能大幅提升转化膜的应用效果,对其稳定性和耐候性也有较大的促进作用。在金属表面涂层、陶瓷涂层以及复合材料涂层中,微纳米α-Al2O3添加剂被广泛用于提高涂层的使用寿命和稳定性。此外,它在电子器件、航天航空和汽车工业等高技术领域也展现了广阔的应用前景。未来,随着表面技术的发展,微纳米α-Al2O3无铬钝化领域的市场应用将大幅增长,与其他功能性材料的协同作用和复合材料开发也将成为研究的重点。Micro-nano α-Al2O3 is an important functional material, because of its excellent hardness, wear resistance, corrosion resistance and high thermal stability, has been widely used in the field of surface coating. With the development of micro-nano technology, the application of micro-nano α-Al2O3 as an additive in various coating systems has been deeply studied, showing its potential to significantly improve coating properties. Micro-nano α-Al2O3 particles have a large specific surface area and surface activity, which can enhance the mechanical properties of the coating, such as hardness and wear resistance, while improving the corrosion resistance and high temperature resistance of the coating. Micro-nano α-Al2O3 is also an excellent modified material, and its composite modification with organosilane, resin and other materials can greatly improve the application effect of conversion film, and also has a greater role in promoting its stability and weather resistance. In metal surface coatings, ceramic coatings and composite coatings, micro-nano α-Al2O3 additives are widely used to improve the service life and stability of coatings. In addition, it also shows broad application prospects in high-tech fields such as electronic devices, aerospace and automotive industries. In the future, with the development of surface technology, the market application of micro-nano α-Al2O3 chromium-free passivation will grow significantly, and the synergy with other functional materials and the development of composite materials will also become the focus of research. 展开更多
关键词 纳米α-Al2O3 无铬钝化涂层 陶瓷膜 表面硬度 耐蚀性
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共沉淀法制备的CeO2-ZrO2-Al2O3材料及性能 认领 引用 被引量：11
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作者 李红梅 周菊发 +4 位作者 祝清超 曾少华 魏振玲 陈耀强 龚茂初 《高等学校化学学报》 SCIE CAS 北大核心 2009年第12期2484-2486,共3页
CeO2-based oxygen materials were prepared with co-precipitation method and characterized via Brunauer-Emmet Teller(BET)method,X-ray diffraction(XRD)and temperature-programmed reduction(H2-TPR).This paper revealed that... CeO2-based oxygen materials were prepared with co-precipitation method and characterized via Brunauer-Emmet Teller(BET)method,X-ray diffraction(XRD)and temperature-programmed reduction(H2-TPR).This paper revealed that three CeO2-based oxygen storage materials are all forming homogeneous solid solution.Among the samples,CeO2-ZrO2-Al2O3(CZA)has the best textural properties and excellent thermal stability.The specific surface area and pore volume of aged CZA are 90 m2/g and 0.29 mL/g.We proposed a viewpoint:Al3+ might insert among the interspace of fluorite structure or highly dispersal in solid solutions. 展开更多
关键词 CeO2-ZrO2-Al2O3 共沉淀法 热稳定性能 结构性能 固溶体
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Synthesis of neodymium modified CeO_2-ZrO_2-Al_2O_3 support materials and their application in Pd-only three-way catalysts 认领 引用 被引量：8
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作者 彭娜 周菊发 +3 位作者 陈山虎 罗秀超 陈耀强 龚茂初 《Journal of Rare Earths》 SCIE EI CAS CSCD 2012年第4期342-349,共8页
Ce-Zr-Al-Nd2O3 （CZAN） support materials were prepared by co-precipitation and impregnation methods, respectively. They were characterized by X-ray diffTaction （XRD）, low temperature nitrogen adsorption-desorption,... Ce-Zr-Al-Nd2O3 （CZAN） support materials were prepared by co-precipitation and impregnation methods, respectively. They were characterized by X-ray diffTaction （XRD）, low temperature nitrogen adsorption-desorption, oxygen pulsing technique, H2-temperamre programmed reduction （H2-TPR） and X-ray photoelectron spectroscopy （XPS）. The Pd-only three-way catalysts （Pd-TWC） supported on these materials were prepared by incipient wetness method and studied by activity tests. The results demonstrated that the CZAN supports obtained by the two methods showed better structural, textural and redox properties than the CZA without Nd2O3, and the addition of Nd203 improved the catalytic activity of TWC. Especially, the CZAN-i support prepared by impregnation method had better thermal stability and redox property. Meanwhile, the Pd/CZAN-i catalyst exhibited the best catalytic performance. XPS measurements indicated that the Nd-modified samples possessed more Ce3＋ and oxygen vacancies on the surface of samples, which led to a better redox property. The excellent redox property of support materials helped to improve the catalytic activity of TWC. 展开更多
关键词 CeO2-ZrO2-Al2O3 support materials Nd2O3 Ce-O-Nd bonds Pd-only three-way catalysts redox property rare earths
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水蒸汽对Ni/CeO_2-ZrO_2-Al_2O_3催化剂上CO_2+CH_4重整反应的影响 认领 引用 被引量：11
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作者 李春林 伏义路 +4 位作者 孟明 卞国柱 谢亚宁 胡天斗 张静 《Chinese Journal of Chemical Physics》 SCIE CAS 北大核心 2004年第1期95-99,共5页
用水热合成法制备了Ni/CeO2 ZrO2 Al2 O3 催化剂 .进行了添加和不添加水蒸汽的CH4 +CO2 催化重整反应 ,测试了活性和稳定性 ,测量了积碳量 ,并用XAFS手段测试了催化剂Ni的K吸收边 .结果表明 ,在反应过程中有CeAlO3 的生成 ,但积碳是无... 用水热合成法制备了Ni/CeO2 ZrO2 Al2 O3 催化剂 .进行了添加和不添加水蒸汽的CH4 +CO2 催化重整反应 ,测试了活性和稳定性 ,测量了积碳量 ,并用XAFS手段测试了催化剂Ni的K吸收边 .结果表明 ,在反应过程中有CeAlO3 的生成 ,但积碳是无水蒸汽添加的反应活性降低的原因 .反应气中添加水蒸汽能够减少积碳 ,从而提高催化反应的稳定性 .由于碳原子插入Ni晶格 ,无水蒸汽反应后的最近邻Ni Ni配位数有较大幅度的减少 .添加了水蒸汽的反应 ,最近邻Ni Ni配位数比反应前减少幅度小 ,这主要是由于在反应气中添加水蒸汽减少了积碳 。 展开更多
关键词 CO2+CH4重整反应 添加水蒸汽 Ni/CeO2-ZrO2-Al2O3催化剂 XAFS 积碳
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不同铈添加量对CeO_2-ZrO_2-Al_2O_3材料性能的影响 认领 引用 被引量：8
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作者 唐石云 焦毅 +4 位作者 李小双 王云 王键礼 龚茂初 陈耀强 《无机化学学报》 SCIE CAS CSCD 北大核心 2012年第5期965-970,共6页
采用共沉淀法制备了一系列不同铈添加量的CeO2-ZrO2-Al2O3(CZA)储氧材料,并通过XRD、低温N2吸附-脱附、氧脉冲吸附(OSC)和H2-TPR等手段进行了表征。XRD结果表明,在1 000和1 100℃高温焙烧后,当CeO2添加量为8%时样品具有最好的结构稳定... 采用共沉淀法制备了一系列不同铈添加量的CeO2-ZrO2-Al2O3(CZA)储氧材料,并通过XRD、低温N2吸附-脱附、氧脉冲吸附(OSC)和H2-TPR等手段进行了表征。XRD结果表明,在1 000和1 100℃高温焙烧后,当CeO2添加量为8%时样品具有最好的结构稳定性能。N2吸附-脱附结果表明,CeO2添加量为8%时样品具有最好的织构性能,1 000℃时,比表面积和孔容分别为:136.6 m2.g-1和0.38 mL.g-1;1 100℃时,比表面积和孔容分别为:83.7 m2.g-1和0.23 mL.g-1。OSC结果显示,CeO2添加量为8%时样品具有最大的储氧量,1 000℃和1 100℃分别为70μmol.g-1和31μmol.g-1。H2-TPR结果表明,CeO2添加量为8%时样品具有最佳的还原性能。 展开更多
关键词 CeO2-ZrO2-Al2O3 结构性能 储氧性能 还原性能
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Catalytic Partial Oxidation of Methane over Ni/CeO_2-ZrO_2-Al_2O_3 认领 引用 被引量：10
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作者 梅大江 陈耀强 +3 位作者 钟俊波 魏振玲 马迪 龚茂初 《Journal of Rare Earths》 SCIE EI CAS 2007年第3期311-315,共5页
Nickel catalysts supported on CeO2-ZrO2-CeO2,ZrO2-Al2O3 and Al2O3 were prepared and characterized by means of X-ray diffraction（XRD）,BET areas,H2 temperature-programmed reduction（H2-TPR）,and X-ray photoelectron sp... Nickel catalysts supported on CeO2-ZrO2-CeO2,ZrO2-Al2O3 and Al2O3 were prepared and characterized by means of X-ray diffraction（XRD）,BET areas,H2 temperature-programmed reduction（H2-TPR）,and X-ray photoelectron spectroscopy（XPS）.Through the test of catalytic partial oxidation of methane（CPOM）,Ni/CeO2-ZrO2-Al2O3 displayed the highest activity,which resulted from its largest BET area and best NiO dispersion.Furthermore,Ni/CeO2-ZrO2-Al2O3 maintained a long-time stability in CPOM,which was attributed to its best coking resistance among all the prepared catalysts. 展开更多
关键词 Ni/CeO2-ZrO2-Al2O3 catalyst catalytic partial oxidation of methane carbon deposition rare earths
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Performance of Pd/CeO_2-ZrO_2-Al_2O_3 catalyst for motorcycle 认领 引用 被引量：5
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作者 赵明 陈山虎 +2 位作者 张晓玉 龚茂初 陈耀强 《Journal of Rare Earths》 SCIE EI CAS 2009年第5期728-732,共5页
The Pd-only catalysts for motorcycle were prepared by impregnating CeO2-ZrO2-Al2O3 and CeO2-ZrO2+Al2O3 with PdCl2 aqueous solution and characterized by X-ray diffraction (XRD), oxygen storage capacity (OSC) and H2-tem... The Pd-only catalysts for motorcycle were prepared by impregnating CeO2-ZrO2-Al2O3 and CeO2-ZrO2+Al2O3 with PdCl2 aqueous solution and characterized by X-ray diffraction (XRD), oxygen storage capacity (OSC) and H2-temperature-programmed reduction (H2-TPR) methods. The XRD result indicated that the CeO2-ZrO2-Al2O3 compound prepared by co-precipitation formed a single solid solution and had good thermal stability, and Pd phase was not observed in all catalysts. The TPR results showed that the reduction temperature of Pd/CeO2-ZrO2-Al2O3 catalyst was lower than that of Pd/CeO2-ZrO2+Al2O3 catalyst whether they were fresh or aged catalysts. The Pd/CeO2-ZrO2-Al2O3 exhibited high three-way catalytic activity at low temperature, high thermal stability, and wide working window, suggesting a great potential for applications. 展开更多
关键词 CeO2-ZrO2-Al2O3 palladium TWC H2-TPR motorcycle rare earths
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复合沉淀剂制备的CeO_2-ZrO_2-Al_2O_3材料及其负载的单Pd三效催化剂(英文) 认领 引用 被引量：6
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作者 李红梅 兰丽 +4 位作者 陈山虎 刘达玉 王卫 龚茂初 陈耀强 《物理化学学报》 SCIE CAS CSCD 北大核心 2016年第7期1734-1746,共13页
采用了一种由氨水和碳酸铵组成的复合沉淀剂来制备CeO_2-ZrO_2-Al_2O_3(CZA)复合氧化物。作为对比,分别采用氨水和碳酸铵为沉淀剂制备了另外两个CZA复合氧化物。系统地研究了各CZA材料在织构、结构、氧化还原性能、热老化行为之间的区别... 采用了一种由氨水和碳酸铵组成的复合沉淀剂来制备CeO_2-ZrO_2-Al_2O_3(CZA)复合氧化物。作为对比,分别采用氨水和碳酸铵为沉淀剂制备了另外两个CZA复合氧化物。系统地研究了各CZA材料在织构、结构、氧化还原性能、热老化行为之间的区别,以及其负载的单Pd三效催化剂的催化性能。结果表明,不同的沉淀剂制得的材料中其CeO_2-ZrO_2(CZ)和Al_2O_3之间的相互作用不同。用氨水做沉淀剂时,得到的材料中CZ和Al_2O_3之间的相互作用很小,导致其热稳定性较差。在碳酸铵做沉淀剂的情况下,CZ和Al_2O_3之间具有很强的相互作用,可以提高材料的热稳定性,但同时,CZ固溶体的均一性被严重破坏,使得材料的氧化还原性能不理想。而复合沉淀剂的使用可以有效地平衡CZ和Al_2O3_之间的相互作用,导致得到的CZA材料具有优异的织构、结构性能及良好的热稳定性。因此,其负载的单Pd催化剂表现出最为优异的氧化还原性能和三效催化活性。 展开更多
关键词 CeO2-ZrO2-Al2O3复合氧化物 复合沉淀剂 单Pd三效催化剂 相互作用 热稳定性
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镧、锰共掺杂改性CeO2-ZrO2-Al2O3固溶体的性能 认领 引用 被引量：5
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作者 张雪乔 信欣 +3 位作者 刘建英 刘盛余 赵明 陈耀强 《高等学校化学学报》 SCIE CAS CSCD 北大核心 2011年第10期2360-2366,共7页
采用共沉淀法制备了一系列La,Mn共掺杂的CeO2-ZrO2-A12O3(CZA)复合氧化物,采用BET,XRD,H2-TPR,XPS和XRF等方法对样品进行表征.结果表明,全部样品均形成了稳定的CZA固溶体,经600℃焙烧后表现出良好的织构性能,1000℃老化后,La,Mn共掺杂... 采用共沉淀法制备了一系列La,Mn共掺杂的CeO2-ZrO2-A12O3(CZA)复合氧化物,采用BET,XRD,H2-TPR,XPS和XRF等方法对样品进行表征.结果表明,全部样品均形成了稳定的CZA固溶体,经600℃焙烧后表现出良好的织构性能,1000℃老化后,La,Mn共掺杂样品具有最佳的高温稳定性;H2-TPR测试表明,La,Mn之间存在正协同效应,共掺杂的样品具有最佳的低温还原性能和高温稳定性;XPS结果表明,掺杂La可有效抑制在焙烧过程中Mn向表面的迁移,从而保持较高的表面吸附氧浓度. 展开更多
关键词 CeO2-ZrO2-Al2O3 MnOx 还原性能
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Structures and oxygen storage capacities of CeO_2-ZrO_2-Al_2O_3 ternary oxides prepared by a green route:supercritical anti-solvent precipitation 认领 引用 被引量：9
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作者 黄盼 姜浩锡 张敏华 《Journal of Rare Earths》 SCIE EI CAS CSCD 2012年第6期524-528,共5页
CeO2-ZrO2-Al2O3 ternary oxides were successfully prepared by a green route of supercritical anti-solvent precipitation with supercritical CO2 as anti-solvent and methanol as solvent. The structures and oxygen storage ... CeO2-ZrO2-Al2O3 ternary oxides were successfully prepared by a green route of supercritical anti-solvent precipitation with supercritical CO2 as anti-solvent and methanol as solvent. The structures and oxygen storage capacities of these ternary oxides were characterized by XRD, Raman spectra and oxygen storage capacity measurements. It was found that Al3＋ and Zr4＋ inserted into CeO2 lattice, forming CeO2-ZrO2-Al2O3 solid solution. The concentration of aluminium isopropoxide in the solution affected the concentration of oxygen vacancy and the distortion of oxygen sublattice which were responsible for the oxygen storage capacity. The rapidest oxygen uptakeelease rate and maximum total oxygen storage capacity （122.0 mmolO2/molCeO2） were obtained with the aluminitun isopropoxide concentration at 0.2 wt.% in the solution. 展开更多
关键词 CeO2-ZrO2-Al2O3 solid solution supercritical anti-solvent precipitation oxygen storage capacity rare earths
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Partial oxidation of methane on Ni/CeO_2-ZrO_2/γ-Al_2O_3 prepared using different processes 认领 引用 被引量：6
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作者 张青蔚 沈美庆 +2 位作者 温静 王军 费亚南 《Journal of Rare Earths》 SCIE EI CAS 2008年第3期347-351,共5页
The influences of CeO2-ZrO2 and γ-Al2O3 mixing methods on the catalytic activity and stability of partial oxidation of methane （POM） were investigated over Ni/Ce0.7Zr0.3O2-Al2O3 catalysts. The catalysts were charac... The influences of CeO2-ZrO2 and γ-Al2O3 mixing methods on the catalytic activity and stability of partial oxidation of methane （POM） were investigated over Ni/Ce0.7Zr0.3O2-Al2O3 catalysts. The catalysts were characterized by XRD, TPR, H2-chemsorption, and TG-DTA. For fresh catalysts, the results showed that the salt precursor mixing catalyst （ATOM） presented better performance than the catalysts prepared by the precipitator mixing method （MOL） and the powder mechanically mixing method （MECH）. The result of XRD suggested that the interaction between CeO2-ZrO2 and Al2O3 in ATOM sample was stronger than the others, which led to more lattice defects and thereby better initial activity. Moreover, the MECH sample had the best stability and the least coke deposition in 24 h stability tests. The results of TPR and H2-chemsorption indicated that the intimate contact of Ni-Al in MECH sample enhanced the ability of resisting coke deposition and metal sintering. 展开更多
关键词 POM CeO2-ZrO2,γ-Al2O3, Ni based catalyst rare earths
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焙烧及还原温度对Co-Pt-ZrO2/γ-Al2O3催化剂费托合成反应性能的影响 认领 引用 被引量：5
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作者 孙燕 孙启文 +2 位作者 蒋凡凯 刘继森 张宗森 《燃料化学学报》 CSCD 北大核心 2012年第1期54-58,共5页
采用浸渍法制备了Co-Pt-ZrO2/γ-Al2O3催化剂,对其进行了BET、XRD和TPR等表征,并在浆态床反应器上考察了焙烧温度和还原温度对催化剂费托合成反应性能的影响。结果表明,焙烧温度过高,容易造成Co物种和载体间的相互作用增强,使部分氧化... 采用浸渍法制备了Co-Pt-ZrO2/γ-Al2O3催化剂,对其进行了BET、XRD和TPR等表征,并在浆态床反应器上考察了焙烧温度和还原温度对催化剂费托合成反应性能的影响。结果表明,焙烧温度过高,容易造成Co物种和载体间的相互作用增强,使部分氧化钴颗粒聚集或烧结,导致催化剂的F-T合成反应活性和C5+烃选择性降低。还原温度较低时,钴物种不能充分还原,CO加氢活性低,甲烷选择性高,重质烃选择性低;还原温度过高,则可能造成活性物种的烧结,反而降低了催化剂的活性和重质烃选择性。在原料气n(H2)(CO)=2.0、483 K、2.4 MPa和空速3.6 L/(gcat.h)的条件下,31.08%Co～0.11%Pt～7.16%ZrO2/Al2O3催化剂在673 K焙烧。纯H2下653 K还原后,其费托性能最佳;CO转化率为27.0%,C5+的选择性为83.0%。 展开更多
关键词 Co-Pt-ZrO2/γ-Al2O3 焙烧温度 还原温度 费托合成
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CeO_2-ZrO_2-La_2O_3-Al_2O_3 composite oxide and its supported palladium catalyst for the treatment of exhaust of natural gas engined vehicles 认领 引用 被引量：5
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作者 Xiaoyu Zhang Enyan,Long +5 位作者 Yile Li Jiaxiu Guo Lijuan Zhang Maochu Gong Minghua Wang Yaoqiang Chen 《Journal of Natural Gas Chemistry》 2009年第2期139-144,共6页
Composite supports CeO2-ZrO2-Al2O3（CZA） and CeO2-ZrO2-Al2O3-La2O3（CZALa） were prepared by co-precipitation method. Palladium catalysts were prepared by impregnation and their purification ability for CH4, CO and N... Composite supports CeO2-ZrO2-Al2O3（CZA） and CeO2-ZrO2-Al2O3-La2O3（CZALa） were prepared by co-precipitation method. Palladium catalysts were prepared by impregnation and their purification ability for CH4, CO and NOx in the mixture gas simulated the exhaust from natural gas vehicles （NGVs） operated under stoichiometric condition was investigated. The effect of La2O3 on the physicochemical properties of supports and catalysts was characterized by various techniques. The characterizations with X-ray diffraction （XRD） and Raman spectroscopy revealed that the doping of La2O3 restrained effectively the sintering of crystallite particles, maintained the crystallite particles in nanoscale and stabilized the crystal phase after calcination at 1000 ℃. The results of N2-adsorption, H2-temperatnre-programmed reduction （H2-TPR） and oxygen storage capacity （OSC） measurements indicated that La2O3 improved the textural properties, reducibility and OSC of composite supports. Activity testing results showed that the catalysts exhibit excellent activities for the simultaneous removal of methane, CO and NOx in the simulated exhaust gas. The catalysts supported on CZALa showed remarkable thermal stability and catalytic activity for the three pollutants, especially for NOx. The prepared palladium catalysts have high ability to remove NOx, CH4 and CO, and they can be used as excellent catalysts for the purification of exhaust from NGVs operated under stoichiometric condition. The catalysts reported in this work also have significant potential in industrial application because of their high performance and low cost. 展开更多
关键词 Pd catalysts natural gas vehicles exhaust methane oxidation NOx conversion CeO2-ZrO2-Al2O3 La2O3
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固体酸催化剂MxOy-ZrO2-Al2O3催化果糖分解制备5-羟甲基糠醛的研究 认领 引用 被引量：4
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作者 黎演明 李秉正 +1 位作者 吴学众 黄日波 《现代化工》 CAS CSCD 北大核心 2012年第11期63-66,共4页
采用溶胶-凝胶法制备了MxOy-ZrO2-Al2O3固体酸催化剂,通过催化果糖分解制备5-羟甲基糠醛(5-HMF)的反应对催化剂的催化性能进行评估。结果表明,相对于其他MxOy-ZrO2-Al2O3催化剂,La2O3-ZrO2-Al2O3具有更高的催化活性。在其催化作用下,于... 采用溶胶-凝胶法制备了MxOy-ZrO2-Al2O3固体酸催化剂,通过催化果糖分解制备5-羟甲基糠醛(5-HMF)的反应对催化剂的催化性能进行评估。结果表明,相对于其他MxOy-ZrO2-Al2O3催化剂,La2O3-ZrO2-Al2O3具有更高的催化活性。在其催化作用下,于120℃与二甲基亚砜溶液反应75 min,5-HMF的收率高达74.91%,生成5-HMF的选择性为77.71%。研究发现La2O3-ZrO2-Al2O3的晶体结构对催化活性有着显著影响,随着催化剂由高结晶结构向无定形转变时,其催化活性出现大幅度减弱。此外,La2O3-ZrO2-Al2O3还具有优异回收性能,重复使用2次后其催化活性几乎保持不变。 展开更多
关键词 果糖 5-羟甲基糠醛 固体酸 MxOy-ZrO2-Al2O3 制备
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C/C-SiC复合材料表面Y_2O_3-ZrO_2-Al_2O_3涂层的涂刷法制备及其抗高温氧化性能 认领 引用 被引量：4
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作者 焦更生 卢国锋 李贺军 《材料保护》 CAS CSCD 北大核心 2014年第7期9-11,6,共3页
为了提高C/C复合材料的抗高温氧化性能,用包埋法在C/C复合材料表面制备SiC内涂层,再在其上刷涂制备Y2O3-ZrO2-Al2O3多组分涂层,对制备涂层的各种影响因素进行分析,确定最佳制备工艺,并考察了该涂层的组织结构和抗高温氧化性能。结果表明... 为了提高C/C复合材料的抗高温氧化性能,用包埋法在C/C复合材料表面制备SiC内涂层,再在其上刷涂制备Y2O3-ZrO2-Al2O3多组分涂层,对制备涂层的各种影响因素进行分析,确定最佳制备工艺,并考察了该涂层的组织结构和抗高温氧化性能。结果表明:最佳制备条件为以SiC为内涂层、10%聚乙烯醇(PVA)为分散剂,以Y2O3,ZrO2,Al2O3,Si及C为原料,室温涂覆,升温到1 873 K保温30 min,反复进行5次;该涂层在1 873 K下氧化19 h,失重率仅1.76%,有良好的短期抗高温氧化性能,氧化29 h时失重率为6.23%,涂层可能已破坏失效;涂层的失效是由于其表面形成的孔洞和裂纹不能愈合而导致的。 展开更多
关键词 Y2O3-ZrO2-Al2O3涂层 涂刷法 C C复合材料 SiC 抗高温氧化性能
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掺杂锆对CeO2-ZrO2-Al2O3复合氧化物还原热处理性能的影响 认领 引用 被引量：2
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作者 杨黄根 谭喻方 +5 位作者 韦庆敏 晏全 陈渊 朱立刚 覃利琴 肖益鸿 《材料工程》 EI CAS CSCD 北大核心 2020年第12期90-96,共7页
采用共沉淀法制备铈锆铝复合氧化物CZ x A(Ce,Zr,Al摩尔比为1∶x∶2,其中x=0,0.5,1,1.5,2)新鲜样品,分别在空气和10%H 2/Ar气氛下进行热处理,利用X射线粉末衍射、N 2吸脱附BET法、O 2脉冲吸附、H 2程序升温还原(H 2 temperature-program... 采用共沉淀法制备铈锆铝复合氧化物CZ x A(Ce,Zr,Al摩尔比为1∶x∶2,其中x=0,0.5,1,1.5,2)新鲜样品,分别在空气和10%H 2/Ar气氛下进行热处理,利用X射线粉末衍射、N 2吸脱附BET法、O 2脉冲吸附、H 2程序升温还原(H 2 temperature-programmed reduction,H 2-TPR)等手段研究复合氧化物的结构及性能。结果表明:CZ x A系列样品随着Zr含量的增加,经1100℃还原热处理的CZ 1.5 A-H 2-1100和CZ 2A-H 2-1100样品没有观察到CeAlO 3晶相;其储氧量分别为713,548μmol·g-1,远大于CZA-H 2-1100的23μmol·g-1;H 2-TPR耗氢量分别为1995,2087μmol·g-1,而CZA-H 2-1100样品H 2-TPR耗氢量显著减小,仅为310μmol·g-1,CZ x A储氧性能受还原热处理时CeAlO 3形成的影响,与H 2-TPR耗氢量的变化结果相吻合。研究发现CA样品经还原热处理更易生成CeAlO 3,而在CA中掺杂一定量Zr元素后的CZ 1.5 A,CZ 2A样品能抑制CeAlO 3的形成,从而显著改善材料的储氧性能和H 2-TPR耗氢量,且铈锆铝材料经还原热处理,均具有更好的低温还原性能。 展开更多
关键词 CeO2-ZrO2-Al2O3 还原热处理 CeAlO3 储氧性能 还原性能
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掺杂不同量Nd_2O_3对CeO_2-ZrO_2-Al_2O_3材料性能的影响 认领 引用 被引量：3
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作者 彭娜 陈山虎 +2 位作者 周菊发 陈耀强 龚茂初 《无机材料学报》 SCIE EI CAS CSCD 北大核心 2012年第11期1138-1144,共7页
采用共沉淀法制备了一系列Nd2O3含量为0～13wt%的CeO2-ZrO2-A12O3(CZA)复合氧化物,并通过X射线衍射(XRD)、低温N2吸附–脱附、氧脉冲吸附(OSC)、H2–程序升温还原(H2-TPR)及扫描电子显微镜(SEM)等方法对所制备的材料进行了表征.研究结... 采用共沉淀法制备了一系列Nd2O3含量为0～13wt%的CeO2-ZrO2-A12O3(CZA)复合氧化物,并通过X射线衍射(XRD)、低温N2吸附–脱附、氧脉冲吸附(OSC)、H2–程序升温还原(H2-TPR)及扫描电子显微镜(SEM)等方法对所制备的材料进行了表征.研究结果表明,Nd2O3在CZA固溶体中的溶解限约为10wt%,过量Nd的添加会出现分相形成Nd0.5Ce0.5O1.75氧化物.掺杂适量Nd能有效抑制氧化物晶粒的长大,提高材料的热稳定性和氧化还原性能.Nd2O3的掺杂量为10wt%时,样品的织构稳定性最好,1000℃老化5 h后,比表面积和孔容分别达97.14 m2/g和0.44 mL/g.Nd2O3的掺杂量为7wt%时,样品有高的储氧量,经600℃和1000℃焙烧后储氧量分别为938.01μmol/g和821.72μmol/g;体相氧的移动能力最强,还原性能最佳,老化后还原峰温由465℃升高到483℃.SEM结果表明,所制备的材料均为球形颗粒,Nd2O3的添加可以有效阻止高温焙烧过程中粒子的团聚. 展开更多
关键词 CeO2-ZrO2-A12O3 织构性能 氧化还原性能
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Structure and mechanical properties of ZrO_2-mullite nano-ceramics in SiO_2-Al_2O_3-ZrO_2 system 认领 引用 被引量：6
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作者 梁叔全 谭小平 +1 位作者 李少强 唐艳 《Journal of Central South University of Technology》 2007年第1期1-6,共6页
ZrO2-mullite nano-ceramics were fabricated by in-situ controlled crystallizing from SiO2-Al2O3-ZrO2 amorphous bulk. The thermal transformation sequences of the SiO2-Al2O3-ZrO2 amorphous bulk were investigated by X-ray... ZrO2-mullite nano-ceramics were fabricated by in-situ controlled crystallizing from SiO2-Al2O3-ZrO2 amorphous bulk. The thermal transformation sequences of the SiO2-Al2O3-ZrO2 amorphous bulk were investigated by X-ray diffraction, infrared spectrum, scanning electron microscope and differential scanning calorimetric. And the mechanical properties of the nano-ceramics were studied. The results show that the bulks are still in amorphous state at 900 ℃ and the t-ZrO2 forms at about 950 ℃ with a faint spinel-like phase which changes into mullite on further heating. ZrO2 and mullite become major phases at 1 100 ℃ and an amount of m-ZrO2 occur at the same time. The sample heated at 950 ℃ for 2 h and then at 1 100 ℃ for 1 h shows very dense and homogenous microstructure with ball-like grains in size of 20-50 nm. With the increase of crystallization temperature up to 1 350 ℃, the grains grow quickly and some grow into lath-shaped grains with major diameter of 5 μm. After two-step treatment the highest micro-hardness, flexural strength and fracture toughness of the samples are 13.72 GPa, 520 MPa and 5.13 MPa·m1/2, respectively. 展开更多
关键词 SiO2-Al2O3-ZrO2 system amorphous bulk heat treatment structural change mechanical properties
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