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报废汽车尾气三元催化剂作为危险废物的同时也是提炼铂族金属重要的资源。介绍了我国废三元催化剂的回收管理政策与主流回收利用技术,分析了上海市废三元催化剂的基本特征与上海市废三元催化剂回收困难的原因,并针对现存问题在政策层面提出了对策建议。 相似文献
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稀土功能材料现状与分析 总被引:8,自引:0,他引:8
对我国稀土材料产品进行了概述,并与世界水平进行了对比,叙述了稀土永磁材料,汽车尾气稀土净化催化剂、稀土荧光粉,稀土钨电极的现状及国内外发展状况和存在问题,对发展稀土新材料进行了分析。 相似文献
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论稀土材料的现状与发展 总被引:2,自引:0,他引:2
对我国稀土材料产品进行了概述,并与世界水平进行对比叙述了稀土永磁材料、稀土汽车尾气净化催化剂、稀土荧光粉、稀土钨电极的现状及国内外发展状况,存在问题,对发展稀土新材料提出了见解。 相似文献
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对我国目前汽车尾气净化稀土催化剂的研究、应用和需求情况进行了综述,分析了我国稀土在该领域应用的不足,展望了其广阔的发展前景。 相似文献
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用浸渍法制备了一系列氧化锆担载的含稀土Ⅷ族金属催化剂,对其在二氧化碳甲烷化过程中的催化活性作了研究,并用漫反射紫外可见光谱,FTIR等手段对催化剂作了表征。结果表明,含稀土新型催化剂具有催化活性高,目标产物选择性好等优点;稀土主要以氧化物形式存在于催化剂表面,参与对氢及表面含碳物种的吸附及活化;含稀土三组份催化剂的活性与所添加稀土三价离子的4f电子数有关。 相似文献
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高效稀土催化剂前景广阔一些轻稀土元素加入于另一种物质中生成复合物后,其化学活性高。选择性好。结构稳定性与热稳定性强,可作为某物质的催化作用的则称为高效稀土催化剂。例如在铝酸钠分子筛结构上,用混合氯化稀土溶液中的稀土阳离子,将分子筛上的钠离子置换出来,... 相似文献
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稀土改性Ni/γ-Al_2O_3催化剂上甲烷化反应积碳的初步研究 总被引:1,自引:0,他引:1
本文系统考察了镧系14种稀土氧化物对镍基甲烷化催化剂积碳的影响,发现大多数稀土的添加使催化剂活性提高,寿命延长,尤以Dy,Pr,Sm效果最佳,主要作用是稀土添加剂促进了甲烷化活性中心数的增长,有抑止积碳的能力,缩短催化剂的增活期。 相似文献
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溴酸钾氧化甲基绿催化光度法测定痕量钯 总被引:6,自引:0,他引:6
研究了稀硫酸介质中痕量Pd(Ⅱ)催化溴酸钾氧化甲基绿的褪色反应及动力学条件,建立了高灵敏度测定痕量Pd(Ⅱ)的新催化光度法。方法的灵敏度为567×10-12g/ml,线性范围为0~01μg/25ml。用于测定矿石中的痕量钯,结果较好。 相似文献
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Different rare earth(RE=La, Ce, Pr, Nd, Sm, Y) and Cu modified nickel catalysts for hydrogen production from methane decomposition were synthesized by a sol-gel process and method. The catalysts were characterized or analyzed through Brumauer-Emmett-Teller(BET), X-ray diffraction(XRD), scanning electron microscopy(SEM), transmission electron microscopy(TEM) techniques. And the hydrogen production performance was also evaluated by a fixed-bed and micro-reaction technique with CH4→C+H2 as a probe reaction. The results showed that rare earth modification had played a great role for nickel catalysts, for example, smaller nickel particles, good thermal stability, high activity, etc. La was the best additive among rare earth modification. The SEM of rare earth modified catalysts showed ordered flower-like structure and rare earth modification made the nickel particles move to the surface of catalysts. In addition, the SEM of nano-carbons was also changed by rare earth modification with long, narrow nano-carbon fibers or tubes obtained. Solid carbon formation was prevented by rare earth modification. 相似文献
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ResearchandDevelopmentofRareEarthAdvancedMaterialsinChinaWangDianzuo(王淀佐),WanQun(万群),YangYuchun(杨遇春)(GeneralResearchInstitute... 相似文献
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介绍了稀土在氨合成催化剂中的研究情况,重点综述了稀土的作用机理及催化性能,还介绍了国内稀土氨合成催化剂性能及工业应用情况。 相似文献
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Effects of Light Rare Earth on Acidity and Catalytic Performance of HZSM-5 Zeolite for Catalytic Cracking of Butane to Light Olefins 总被引:1,自引:0,他引:1
The effects of rare earth(RE)on the structure,acidity,and catalytic performance of HZSM-5 zeolite were investigated.A series of RE/HZSM-5 catalysts,containing 7.54% RE(RE=La,Ce,Pr,Nd,Sm,Eu or Gd),were prepared by the impregnation of the ZSM-5 type zeolites(Si/Al=64:1)with the corresponding RE nitrate aqueous solutions.The catalysts were characterized by means of FT-IR,UV-Vis,NH3-TPD,and IR spectroscopy of adsorbed pyridine.The catalytic performances of the RE/HZSM-5 for the catalytic cracking of mixed butane to light olefins were also measured with a fixed bed microreactor.The results revealed that the addition of light rare earth metal on the HZSM-5 catalyst greatly enhanced the selectivity to olefins,especially to propylene,thus increasing the total yield of olefins in the catalytic cracking of butane.Among the RE-modified HZSM-5 samples,Ce/HZSM-5 gave the highest yield of total olefins,and Nd/HZSM-5 gave the highest yield of propene at a reaction temperature of 600℃.The presence of rare earth metal on the HZSM-5 sample,not only modified the acidic properties of HZSM-5 including the amount of acid sites and acid type,that is,the ratio of L/B(Lewis acid/Brnsted acid),but also altered the basic properties of it,which in turn promoted the catalytic performance of HZSM-5 for the catalytic cracking of butane. 相似文献
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Surface compositions,structures,and acidities of the Mo-Te-Fe-Ni catalysts added with La_2O_3,CeO_2,Pr_6O_(12),Nd_2O_3 and Sm_2O_3 were measured and related with the activities of the catalysts for selective oxidationof olefins.It was found that adding rare earth elements to the Mo-Te catalysts increases obviously theirselectivities to methacrolein(MAL),and the yield percentage of MAL changes periodically with the increase ofatomic numbers of rare earth elements added,and the highest yield was obtained with the catalyst containingCeO_2.The addition of CeO_2 to 9-component Mo-Te catalyst increases not only the activity of the catalyst,but also its thermostability remarkably.The mechanism of rare earth elements in the catalysts was discussed. 相似文献
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Inordertoimprovetheactivityandselectivitytodimethylamine(DMA)inaminationreaction,manyresearchershavedonemanyworksmainlyonthe... 相似文献