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Preparation and Characterization of CeO_2-ZrO_2 Solid Solution Ultrafine Particles Using Reversed Microemulsion 被引量:4
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作者 安源 李丽 +1 位作者 王军 沈美庆 《Journal of Rare Earths》 SCIE EI CAS CSCD 2005年第4期416-419,共4页
Ce0.6Zr0.4O2 solid solution ultrafine particle was prepared in the cyclohexane/water/OP-10/n-hexanol reversed microemulsion. The quasi-ternary phase diagram investigations showed that the system has narrow W/O type mi... Ce0.6Zr0.4O2 solid solution ultrafine particle was prepared in the cyclohexane/water/OP-10/n-hexanol reversed microemulsion. The quasi-ternary phase diagram investigations showed that the system has narrow W/O type microemulison region, so it is the proper system to prepare Ce0.6Zr0.4O2 solid solution ultrafine particle. Some physical-chemical techniques such as TG/DTA, XRD, BET, and HRTEM are used to characterize the resultant powders. The results show that the fluorite cubic Ce0.6Zr0.4O2 solid solution is obtained at 400 ℃. The surface area is (146.7 m^2·g^-1), which is higher than the surface area for sol-gel prepared sample (59.5m^2·g^-1). HRTEM images indicated that the Ce0.6Zr0.4O2 solid solution ultrafine particle is well-crystallized, narrow size distribution, less agglomeration, within mean size of 5 -7 nm. 展开更多
关键词 reverse microemulsion ceo2-zro2 solid solution ultrafine particle rare earths
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Preparation,characterization and catalytic properties of S_2O_8^(2-)/ZrO_2-CeO_2 solid superacid catalyst 被引量:25
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作者 樊国栋 沈茂 +1 位作者 张昭 贾发瑞 《Journal of Rare Earths》 SCIE EI CAS CSCD 2009年第3期437-442,共6页
A novel solid superacid catalyst S2O8^2-/ZrO2-CeO2 was prepared by a coprecipitation method and characterized by means of XRD FTIR, BET, TEM and DSC/TG analysis methods. The results indicated that incorporation of app... A novel solid superacid catalyst S2O8^2-/ZrO2-CeO2 was prepared by a coprecipitation method and characterized by means of XRD FTIR, BET, TEM and DSC/TG analysis methods. The results indicated that incorporation of appropriate amounts of Ce into the catalyst was beneficial to the formation of sole tetragonal ZrO2 and effectively prevented from the formation of monoclinic ZrO〉 and restrained the loss of sulfated species. XRD revealed the presence of tetragonal Ce0.16Zr0.84O2phase in the case of S2O8^2-/ZrO2-CeO2 calcined above 500 ℃. Catalytic activities of S2O8^2-/ZrO2-CeO2 for the esterification of lactic acid with n-butanol was studied. The results showed that the optimum conditions were as follows: calcination temperature of the catalyst 600 ℃, n(lactic acid):n(n-butyl alcohol)=1.0:3.0, w(S2O8^2-/ZrO2- CeO2)=12.0%, reaction temperature 145 ℃, and reaction time 2 h. The esterification efficiency of lactic acid was about 96.6%. 展开更多
关键词 solid superacid catalyst S2O8^2-/zro2-ceo2 n-butyl lactate ESTERIFICATION rare earths
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添加水蒸气对CH_4-CO_2重整催化剂Ni/CeO_2-ZrO_2-Al_2O_3中Ni组分结构影响的EXAFS研究 被引量:3
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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 《核技术》 CAS CSCD 北大核心 2002年第10期879-882,共4页
采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气的CH4 -CO2 催化重整反应 ,测量了积碳量 ,并用EXAFS手段测试了催化剂Ni的K吸收边。结果表明 ,反应前后最近邻Ni-Ni配位距离无明显变化 ,而配位数却变化明... 采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气的CH4 -CO2 催化重整反应 ,测量了积碳量 ,并用EXAFS手段测试了催化剂Ni的K吸收边。结果表明 ,反应前后最近邻Ni-Ni配位距离无明显变化 ,而配位数却变化明显。无水蒸气反应后Ni-Ni配位数有较大幅度的减少 ;而添加了水蒸气 ,Ni-Ni配位数比反应前减少幅度小。水蒸气的添加能减少积碳量 ,稳定催化剂中Ni的结构 。 展开更多
关键词 CH4 CO2 ceo2 zro2 Al2O3 Ni组分 水热合成法 铈锆固熔体 催化剂 EXAFS 水蒸汽 合成气 氧化铝 二氧化铈 甲烷 二氧化碳 氧化锆
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添加稀土氧化物助剂的CeO_2-ZrO_2固溶体的储氧性及热稳定性研究 被引量:6
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作者 田久英 袁书华 +6 位作者 林之恩 陈耀强1 龚茂初 万家义 吴朗 苏含秋 任荣康 《化学研究与应用》 CAS CSCD 2000年第5期543-546,共4页
Three kinds of REO modified CeO 2 ZrO 2 solid solutions were prepared by co precipitate method.TPR and XRD measurements have been used to characterize the effect of REO on the thermal stability and oxygen storage prop... Three kinds of REO modified CeO 2 ZrO 2 solid solutions were prepared by co precipitate method.TPR and XRD measurements have been used to characterize the effect of REO on the thermal stability and oxygen storage properties of CeO 2 ZrO 2 solid solutions,comparison being made with unmodified CeO 2 ZrO 2 solid solutions.The results indicated that the addition of REO to CeO 2 ZrO 2 solid solutions obviously improved the oxygen storage properties of the three kinds of solid solutions calcinated at 773K.Except for Zr rich solid solutions,the modified CeO 2 ZrO 2 solid soltuions calcinated at 1173K show higher thermal stability and oxygen storage properties than unmodified solid solutions. 展开更多
关键词 ceo2-zro2固溶体 储氧性 汽车尾气净化 催化剂
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Role of Microstructure and Spectrum Features on the Catalysis Effect of Ce1-x(Nd0.5Eu0.5)xO2-δSolid Solutions
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作者 张国芳 侯忠辉 +2 位作者 翟亭亭 许剑轶 张羊换 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2018年第1期44-54,共11页
Nanosized Ce^1-x)(Nd^0.5)Eu^0.5))xO^2-δ) solid solutions(x = 0.00-0.20) were synthesized by means of hydrothermal method.Then the solid solutions were ball milled with Mg2Ni and Ni powders for 20 h to get the... Nanosized Ce^1-x)(Nd^0.5)Eu^0.5))xO^2-δ) solid solutions(x = 0.00-0.20) were synthesized by means of hydrothermal method.Then the solid solutions were ball milled with Mg2Ni and Ni powders for 20 h to get the Mg2Ni–Ni–5 mol% Ce^1-x)(Nd^0.5)Eu^0.5))xO^2-δ) composites.The structures and spectrum characteristics of the Ce^1-x)(Nd^0.5)Eu^0.5))xO^2-δ) solid solutions catalysts were analyzed systemically.XRD results showed that the doped samples exhibited single phase of CeO2 fluorite structure.The cell parameters and cell volumes were increased with increasing the doped content.Raman spectrum revealed that the peak position of F^2g mode shift to higher wavenumbers and the peak corresponding to oxygen vacancies were observed distinctly for the doped samples.UV-Vis technique indicated that the absorption peaks of Eu^3+ and Nd^3+ ions appeared; the bandgap energy was decreased linearly.The electrochemical and kinetic properties of the Mg2Ni–Ni–5 mol% Ce1-x(Nd0.5Eu0.5xO2-δ composites were measured.The maximum discharge capacity was increased from 722.3 mA h/g for x = 0.00 to 819.7 mA h/g for x = 0.16,and the cycle stability S20 increased from 25.0%(x = 0.00) to 42.2%(x = 0.20).The kinetic measurement proved that the catalytic activity of composite surfaces and the hydrogen diffusion rate were improved for the composites with doped catalysts,especially for the composites with x = 0.16 and x = 0.20.The catalysis mechanism was analyzed from the point of microstructure and spectrum features of the Ce1-x(Nd0.5Eu0.5)xO2-δ solid solutions. 展开更多
关键词 hydrothermal method Ce1-x(Nd0.5Eu0.5)xO2-δ solid solutions Mg2Ni ball milling catalysis mechanism
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固体电解质ZrO_2-CeO_2-SrO超细粉的制备
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作者 肖秋国 邓文 刘可 《湘潭矿业学院学报》 EI 2000年第3期57-60,共4页
通过试验研制出了ZrO2 -CeO2 -SrO固体电解质超细粉 研究表明 ,其颗粒粒径随母液的浓度的增大、氨水的加入量的减少、烧结温度的提高及烧结时间的延长而增大 ,粒径分布的范围也增大 ,适宜条件分别为 0 .1mol/L ,pH为 1 4,70 0℃ ,4h .... 通过试验研制出了ZrO2 -CeO2 -SrO固体电解质超细粉 研究表明 ,其颗粒粒径随母液的浓度的增大、氨水的加入量的减少、烧结温度的提高及烧结时间的延长而增大 ,粒径分布的范围也增大 ,适宜条件分别为 0 .1mol/L ,pH为 1 4,70 0℃ ,4h .通过SEM观察 ,颗粒呈无规则形状 ,通过XRD分析了氧化物之间的结合情况 ,发现有固溶体产生 图 3,表 4,参 展开更多
关键词 超细粉 固体电解质 SOFC 氧化物陶瓷
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A rationale for the development of thermally stable nanostructured CeO_2-ZrO_2-containing mixed oxides 被引量:10
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作者 Roberta Di Monte Jan Kapar +1 位作者 Heather Bradshaw Colin Norman 《Journal of Rare Earths》 SCIE EI CAS CSCD 2008年第2期136-140,共5页
CeO2-ZeO2 solid solutions are extensively used as oxygen storage promoters in the current automotive three-way catalysts. High thermal stability of the textural properties is one of the most important requirements for... CeO2-ZeO2 solid solutions are extensively used as oxygen storage promoters in the current automotive three-way catalysts. High thermal stability of the textural properties is one of the most important requirements for practical application since temperatures up to 1273 K are easily experienced by these materials under real working conditions. In the present paper, we investigated how hydrothermal treatments applied to cakes of doped and undoped ZrO2-rich CeO2-ZrO2 precursors might improve the thermal stability of the final CeO2-ZrO2 solid solution. A rationale was developed that allowed to correlate the morphology of the hydrothermaUy treated cake with the thermal stability at 1273 K of the final product, which did not depend on the composition of the mixed oxides. 展开更多
关键词 ceo2-zro2 mixed oxides ceo2-zro2 solid solution ceo2-zro2 mixed oxides thermal stability of three-way catalysts oxygen storage capacity rare earths
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Catalytic reduction of SO_2 by CO over CeO_2-TiO_2 mixed oxides 被引量:5
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作者 张丽 秦毅红 +3 位作者 陈白珍 彭亚光 何汉兵 袁依 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第11期2960-2965,共6页
The structure and catalytic desulfurization characteristics of CeO2-TiO2 mixed oxides were investigated by means ofX-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and catalytic activity tests. Acco... The structure and catalytic desulfurization characteristics of CeO2-TiO2 mixed oxides were investigated by means ofX-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and catalytic activity tests. According to the results, a CeO2-TiO2solid solution is formed when the mole ratio of cerium to titanium n(Ce):n(Ti) is 5:5 or greater, and the most suitable n(Ce):n(Ti) isdetermined as 7:3, over which the conversion rate of SO2 and the yield of sulfur at 500℃ reach 93% and 99%, respectively.According to the activity testing curve, Ce0.7Ti0.3O2 (n(Ce):n(Ti)=7:3) without any pretreatment can be gradually activated by reagentgas after about 10 min, and reaches a steady activation status 60 min later. The XPS results of Ce0.7Ti0.3O2 after different time ofSO2+CO reaction show that CeO2 is the active component that offers the redox couple Ce4+/Ce3+ and the labile oxygen vacancies, andTiO2 only functions as a catalyst structure stabilizer during the catalytic reaction process. After 48 h of catalytic reaction at 500℃,Ce0.7Ti0.3O2 still maintains a stable structure without being vulcanized, demonstrating its good anti-sulfur poisoning performance. 展开更多
关键词 ceo2-TiO2 mixed oxides solid solution catalytic reduction carbon monoxide sulfur dioxide
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Y_2O_3和CeO_2复合掺杂ZrO_2纳米晶的制备与表征 被引量:9
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作者 庞松 侯书恩 +1 位作者 张涛 刘贺年 《中国稀土学报》 CAS CSCD 北大核心 2007年第6期755-759,共5页
以ZrOCl2.8H2O,Y2O3,Ce(NO3)3.5.5H2O为原料,NH3.H2O作沉淀剂,少量表面活性剂PE作分散剂,采用反向共沉淀-喷雾干燥法,结合物理、化学分散技术,成功地制备了Y2O3,CeO2复合掺杂ZrO2纳米粉末。通过DSC-TG,XRD,XPS,BET和SEM等方法对所制... 以ZrOCl2.8H2O,Y2O3,Ce(NO3)3.5.5H2O为原料,NH3.H2O作沉淀剂,少量表面活性剂PE作分散剂,采用反向共沉淀-喷雾干燥法,结合物理、化学分散技术,成功地制备了Y2O3,CeO2复合掺杂ZrO2纳米粉末。通过DSC-TG,XRD,XPS,BET和SEM等方法对所制得粉末进行了表征。结果表明:以Ce0.1Y0.1Zr0.8O1.95化学计量比制备的多元氢氧化物胶体经过喷雾干燥处理后,在500℃基本完成水合氧化物的分解,577℃附近完成由非晶相向立方相的转变;经过580-1000℃煅烧后,CeO2和Y2O3已经完全固溶到ZrO2中,形成类质同相体,该粉末系列均属于立方相萤石结构;掺杂进入ZrO2晶格中的Ce呈+4价形式存在;比表面积由22.0 m^2.g^-1(580℃煅烧)减至4.97 m^2.g^-1(1000℃煅烧);SEM结果显示800℃煅烧的该粉末颗粒尺寸分布均匀,多呈类球状,且粒径在50-80 nm。 展开更多
关键词 纳米zro2粉末 反向共沉淀-喷雾干燥法 Y2O3 ceo2复合掺杂 稀土
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Y^(3+)和La^(3+)改性对CeO_2(ZrO_2)/TiO_2催化剂脱硝性能的影响 被引量:5
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作者 金奇杰 陶兴军 +2 位作者 潘有春 沈岳松 祝社民 《热力发电》 CAS 北大核心 2018年第2期71-77,共7页
采用溶胶-凝胶法制备Y^(3+)和La^(3+)掺杂CeO_2(ZrO_2)/TiO_2(简称CZT)催化剂,研究Y^(3+)和La^(3+)掺入对其脱硝性能的影响。采用X射线衍射、氮气吸附脱附、氨气程序升温吸附、氢气程序升温还原以及紫外光光致发光光谱等实验方法对CZT... 采用溶胶-凝胶法制备Y^(3+)和La^(3+)掺杂CeO_2(ZrO_2)/TiO_2(简称CZT)催化剂,研究Y^(3+)和La^(3+)掺入对其脱硝性能的影响。采用X射线衍射、氮气吸附脱附、氨气程序升温吸附、氢气程序升温还原以及紫外光光致发光光谱等实验方法对CZT催化剂进行表征。结果表明:Y^(3+)和La^(3+)的掺入抑制了TiO_2从无定形向锐钛矿型转变,不仅增大了催化剂的弱酸酸量和比表面积,同时提高了CZT催化剂的缺陷浓度和储释氧性能;弱酸酸量和比表面积的增大有利于CZT催化剂表面反应气体的吸附;缺陷浓度和储释氧性能的提高加快了吸附在CZT催化剂表面的NO被氧化速率,有利于催化反应的进行。因此,适量掺入Y^(3+)和La^(3+)会明显提升CZT催化剂的低温脱硝活性,拓宽其活性温度窗口。空速71 400 h-1条件下,0.2LaCZT催化剂在200℃的脱硝率达到85.1%,300℃达到最高(96.5%)。 展开更多
关键词 ceo2(zro2)/TiO2 脱硝活性 催化剂 酸性位 溶胶-凝胶 La3+ Y3+ 改性
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Al^(3+)掺入对CeO_2(ZrO_2)/TiO_2催化剂脱硝性能的影响
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作者 金奇杰 潘有春 +2 位作者 陶兴军 沈岳松 祝社民 《化工新型材料》 CAS CSCD 北大核心 2018年第7期227-231,共5页
采用溶胶-凝胶法制备Al ^(3+)掺杂CeO_2(ZrO_2)/TiO_2催化剂,研究了Al ^(3+)掺入对CeO_2(ZrO_2)/TiO_2催化剂脱硝性能的影响。采用X射线衍射、氮气吸附脱附、氨气程序升温吸附、氢气程序升温还原以及荧光光谱等表征技术对催化剂进行表... 采用溶胶-凝胶法制备Al ^(3+)掺杂CeO_2(ZrO_2)/TiO_2催化剂,研究了Al ^(3+)掺入对CeO_2(ZrO_2)/TiO_2催化剂脱硝性能的影响。采用X射线衍射、氮气吸附脱附、氨气程序升温吸附、氢气程序升温还原以及荧光光谱等表征技术对催化剂进行表征。结果表明:Al ^(3+)的掺入有利于抑制TiO2从无定型相向锐钛矿相转变,增强了催化剂的储释氧性能,提高了催化剂的强酸酸量和缺陷浓度。强酸酸量和缺陷浓度的提高有利于反应气体的吸附;储释氧性能的增强,吸附的NO物种被氧化的速率加快,有利于催化反应的进行。因此,适量Al ^(3+)的掺入会明显提升CeO_2(ZrO_2)/TiO_2催化剂的高温脱硝活性,拓宽活性温度窗口。71400h-1条件下0.8Al-CZT催化剂在330℃达到最高活性(98.9%)且在400℃脱硝活性依然能够维持90.8%。 展开更多
关键词 ceo2(zro2)/TiO2 烟气脱硝 酸性位 溶胶-凝胶法
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Surface and Texture Properties of Tb-Doped Ceria-Zirconia Solid Solution Prepared by Sol-Gel Method 被引量:6
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作者 樊国栋 冯长根 张昭 《Journal of Rare Earths》 SCIE EI CAS CSCD 2007年第1期42-47,共6页
The three-way catalysts (TWCs) promoters Ce0.6Zr0.4- x TbxO2-y were prepared by sol-gel method. BET surface areas analysis indicated that an increase of the dopant Tb content from x = 0.05 to x = 0.15 favors an incr... The three-way catalysts (TWCs) promoters Ce0.6Zr0.4- x TbxO2-y were prepared by sol-gel method. BET surface areas analysis indicated that an increase of the dopant Tb content from x = 0.05 to x = 0.15 favors an increase of surface area from 66.8 to 80.4 m^2· g^-1 compared with the undoped sample Ce0 .6oZr0.40O2 65.1 m^2·g^- 1 after calcination at 650℃. Transmission electron microscopy (TEM) observation indicated that the doped samples have a higher thermal stability. The XRD and Raman spectra confirmed that the Ce0.6Zr0.4-xTbxO2-y cubic solid solution is formed. XPS analysis revealed that Ce and Tb mainly existed in the form of Ce^4+ and Tb^3 + , and Zr existed in the form of Zr^4+ on the surface of the samples. The doped samples were homogenous in composition ; the introduction of Tb into the CeO2-ZrO2 promoters resuited in the formation of a solid solution, and the concentration of surface lattice oxygen was increased. 展开更多
关键词 Ce0.6Zr0.4 - xTbxO2 - y solid solution three-way catalysts sol-gel method surface and texture structure rare earths
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水热法制备Ni/Zr_(0.4)Ce_(0.6)O_2-Al_2O_3催化剂上CH_4-CO_2重整反应研究:NiO含量的影响 被引量:5
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作者 李春林 伏义路 卞国柱 《燃料化学学报》 EI CAS CSCD 北大核心 2002年第5期468-472,共5页
采用水热合成法制备不同NiO含量的Ni Zr0 4 Ce0 6 O2 Al2 O3催化剂 ,使用X射线衍射 (XRD)和H2 的程序升温还原 (H2 TPR)对样品进行表征 ,研究了NiO的含量对催化剂结构和CH4 CO2 重整性能的影响。结构表征表明 ,少量Ni组分能在催化... 采用水热合成法制备不同NiO含量的Ni Zr0 4 Ce0 6 O2 Al2 O3催化剂 ,使用X射线衍射 (XRD)和H2 的程序升温还原 (H2 TPR)对样品进行表征 ,研究了NiO的含量对催化剂结构和CH4 CO2 重整性能的影响。结构表征表明 ,少量Ni组分能在催化剂表面分散并进入CeO2 ZrO2 固熔体晶格间隙而被固熔体包裹 ,并使固熔体晶粒变小 ,促进了固熔体的低温还原 ,而过量的NiO暴露在外生成NiO颗粒。活性测试结果表明 ,NiO含量少的样品活性随反应进行有较高的增长。选择适当空速 ,能使CH4 CO2 以 1∶1反应。 展开更多
关键词 水热法 制备 Ni/Zr0.4Ce0.6O2-Al2O3催化剂 氧化铝 掺杂 镍基催化剂 催化重整 铈锆固熔体 甲烷 二氧化碳
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High-pressure synthesis and properties of CeO_2-ZrO_2 solid solution
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作者 XU Dapeng, WANG Quanyong, LU Zhe, LIU Zhiguo, ZHANG Gongmu & SU Wenhui1. Department of Physics, Jilin University, Changchun 130023 China 2. International Center for Materials Physics, Chinese Academy of Sciences, Shenyang 110015, China 3. Center for Condensed Matter and Radiation Physics, China Center of Advanced Science and Technology (World Laboratory), Beijing 100080, China 《Chinese Science Bulletin》 SCIE EI CAS 2001年第10期801-806,共6页
Using nanoparticles of CeO2 and ZrO2 prepared by the chemical precipitation method as starting materials, the single-phase cubic Ce0.5Zr0.5O2 solid solution (c-Ce0.5Z0.5O2) has been synthesized under 3.1 GPa at 1073 K... Using nanoparticles of CeO2 and ZrO2 prepared by the chemical precipitation method as starting materials, the single-phase cubic Ce0.5Zr0.5O2 solid solution (c-Ce0.5Z0.5O2) has been synthesized under 3.1 GPa at 1073 K for the first time. The structure of the c-Ce0.5Zr0.5O2 has not been changed before and after annealing at 773 K for 1 h. Only an unknown EPR signal (g =1.990) has been observed in the c-Ce0.5Zr0.5O2 and not varied after annealing at 773 K for 1 h, which exhibited that there exists no Ce3+ in the c-Ce0.5Zr0.5O2 and the Ce4+ has not been reduced into Ce3+ after annealing. The transport mechanism is ionic for the c-Ce0.5Zr0.5O2. The bulk conductivity (a =1.2×10-5 S/cm at 823 K, σ=2.1 ×10-3 S/cm at 1123 K) is the same as that of CeO2, but smaller than that of Y2O3-stabilized ZrO2. A marked curvature at T = 823 K has been observed in the Arrhenius plot of the bulk conductivity. The activation energy below 823 K is lower than that above 823 K, and the reason has been discussed. 展开更多
关键词 ceo2-zro2 NANOCRYSTALLINE high-pressure and -temperature solid-STATE REACTION solid solution.
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Preparation and Structural Defects of Al_(2-x)Zr_(x+y)Ti_(1-y)O_5 and Al_(4.54)Si_(1.46)O_(9.73) Multiphase Material
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作者 罗金荣 阮玉忠 林寿 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2012年第2期155-160,共6页
In the study, sludge from the aluminum profile factory and kaolin were used as the raw materials. Through adding ZrO2 mineralizer in different contents, Al2-xZrx+yTi1-yO5 and Al4.54Si1.46O9.73 solid solution multipha... In the study, sludge from the aluminum profile factory and kaolin were used as the raw materials. Through adding ZrO2 mineralizer in different contents, Al2-xZrx+yTi1-yO5 and Al4.54Si1.46O9.73 solid solution multiphase material was prepared to effectively inhibit the decomposition of aluminum titanate solid solution and optimize high temperature property of the multiphase material. With XRD and SEM means, crystalline structure and microstructure of each sample were characterized, and properties of each sample were tested. According to experimental results, the optimal addition amount of ZrO2 mineralizer was determined to be 1.5%. Correspondingly, contents for aluminum titanate solid solution, mullite solid solution and α-Al2O3 were 70.3%, 26.8% and 2.9% respectively, bulk density was 3.20 g/cm3, degree of porosity was 5.57%, water absorption rate was 1.74%, and the once thermal shock rupture strength retention rate was 90.52%. 展开更多
关键词 zro2 mineralizer aluminum titanate solid solution mullite solid solution crystalline phase property
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Distribution of P2O5 between solid solution and liquid phase in dephosphorization slag of CaO-SiO2-FeO-P2O5-Na2O system 被引量:1
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作者 Chuan-ming Du Ning-ning Lv +3 位作者 Chang Su Wei-ming Liu Jin-xing Yang Hai-chuan Wang 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2019年第11期1162-1170,共9页
A multi-phase slag containing Na2O is potential to efficiently dephosphorize high-P hot metal.After dephosphorization,the generated slag with high P2O5 content is regarded as a P resource.Because P2O5 was mainly conce... A multi-phase slag containing Na2O is potential to efficiently dephosphorize high-P hot metal.After dephosphorization,the generated slag with high P2O5 content is regarded as a P resource.Because P2O5 was mainly concentrated in the 2CaO SiO2-3CaO P2O5 solid solution,the recovery of P from dephosphorization slag primarily depends on the separation of the solid solution from other phases.The distribution ratios of P2O5 between solid solution and liquid phase in the CaOSiO2-FeO-P2O5-Nslag system were investigated.The results indicated that the addition of Na2O facilitated the enrichment of P2O5 in the solid solution because it increased not only the distribution ratio of P2O5 but also the mass fraction of the solid solution.The distribution ratio of P2O5 was independent of the P2O5 content in slag.A higher P2O5 content in slag resulted in higher P2O5 and Na2O contents in the solid solution.The distribution ratio of P2O5 increased with the total Fe content in the liquid phase,regardless of the valence of Fe.An increase in the FeO content in slag brought a higher P2O5 content in the solid solution.As slag basicity increased,the distribution ratio of P2O5 increased,but the P2O5 content in the solid solution decreased. 展开更多
关键词 DEPHOSPHORIZATION Steelmaking slag Distribution ratio P2O5 2CaO·SiO2-3CaO·P2O5 solid solution
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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 被引量:8
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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 uptake/release 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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Effect of water vapor on the CO and CH_4 catalytic oxidation over CeO_2-MO_x (M=Cu, Mn, Fe, Co, and Ni) mixed oxide 被引量:9
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作者 乔东升 卢冠忠 +2 位作者 郭耘 王艳芹 郭杨龙 《Journal of Rare Earths》 SCIE EI CAS CSCD 2010年第5期742-746,共5页
CeO2-MOx (M=Cu, Mn, Fe, Co, and Ni) mixed oxide catalysts were prepared by a citric acid complexation-combustion method. CeO2-MOx solid solutions could be formed with M cations doping into CeO2 lattice, while NiO and ... CeO2-MOx (M=Cu, Mn, Fe, Co, and Ni) mixed oxide catalysts were prepared by a citric acid complexation-combustion method. CeO2-MOx solid solutions could be formed with M cations doping into CeO2 lattice, while NiO and Co3O4 phases were detected on the surface of CeO2-NiO and CeO2-Co3O4 by Raman spectroscopy. The presence of M in CeO2 could obviously promote its catalytic activity for CH4 catalytic combustion and CO oxidation. Among the prepared samples, CeO2-CuO exhibited the best performance for CO oxidatio... 展开更多
关键词 ceo2-MOx solid solution catalytic oxidation methane combustion CO oxidation effect of water vapor rare earths
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Catalytic Activity of Ceria-Zirconia Nanostructured Materials Prepared via Reversed Microemulsion Method 被引量:4
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作者 安源 朱凌云 +1 位作者 王军 沈美庆 《Journal of Rare Earths》 SCIE EI CAS CSCD 2005年第6期690-694,共5页
Single-phase homogeneous Ce1-x ZrxO2 solid versed microemulsion method. The structural properties solutions with various compositions were synthesized using the reand performance of Ce1- xZrxO2 were studied using XRD,... Single-phase homogeneous Ce1-x ZrxO2 solid versed microemulsion method. The structural properties solutions with various compositions were synthesized using the reand performance of Ce1- xZrxO2 were studied using XRD, BET, SEM, HRTEM, TPR and CO oxidation measurements. The results show that in the range of x = 0.4 - 0.5 and x = 0.6 - 1.0, the solid solutions posses the cubic and the tetragonal phase structure, respectively, Solids obtained by the reversed microemulsion method were more homogeneous on the whole range of composition, XRD investigations of the prepared materials did not show segregation of cerium or zirconium oxides, Highly uniform nanosize solid solution particles of ceria-zirconia with high specific area (146.7 m^2·g^-1) were attained under the conditions of this study. The TPR results and CO oxidation measurements indicate that the performance of the CeO2-ZrO2 mixed oxides is strongly related to the composition and structure of the oxides. Enhancement of the activity was found for the catalyst prepared by reversed microemulsion method as compared to the sample prepared by sol-gel method. 展开更多
关键词 ceo2-zro2 solid solution reversed microemulsion NANOSIZE catalytic property carbon monoxide oxidation rare earths
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Activity and hydrothermal stability of CeO_2–ZrO_2–WO_3 for the selective catalytic reduction of NO_x with NH_3 被引量:7
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作者 Zhongxian Song Ping Ning +5 位作者 Qiulin Zhang Hao Li Jinhui Zhang Yancai Wang Xin Liu Zhenzhen Huang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2016年第4期168-177,共10页
A series of CeO2–ZrO2–WO3(CZW)catalysts prepared by a hydrothermal synthesis method showed excellent catalytic activity for selective catalytic reduction(SCR)of NO with NH3 over a wide temperature of 150–550℃.... A series of CeO2–ZrO2–WO3(CZW)catalysts prepared by a hydrothermal synthesis method showed excellent catalytic activity for selective catalytic reduction(SCR)of NO with NH3 over a wide temperature of 150–550℃.The effect of hydrothermal treatment of CZW catalysts on SCR activity was investigated in the presence of 10% H2O.The fresh catalyst showed above 90% NOx conversion at 201–459℃,which is applicable to diesel exhaust NOx purification(200–440℃).The SCR activity results indicated that hydrothermal aging decreased the SCR activity of CZW at low temperatures(below 300℃),while the activity was notably enhanced at high temperature(above 450℃).The aged CZW catalyst(hydrothermal aging at 700℃ for 8 hr)showed almost 80% NOx conversion at 229–550℃,while the V2O5–WO3/TiO2 catalyst presented above 80% NOx conversion at 308–370℃.The effect of structural changes,acidity,and redox properties of CZW on the SCR activity was investigated.The results indicated that the excellent hydrothermal stability of CZW was mainly due to the CeO2–ZrO2 solid solution,amorphous WO3 phase and optimal acidity.In addition,the formation of WO3 clusters increased in size as the hydrothermal aging temperature increased,resulting in the collapse of structure,which could further affect the acidity and redox properties. 展开更多
关键词 ceo2zro2–WO3 Hydrothermal stability solid solution Acidity
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