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第八届国际稀土开发与应用研讨会暨第三届中国稀土峰会

作者： Jianjun XIE Yu WANG Zhi SUN Lincong FAN Lei ZHANG Fang LEI Ying SHI Department of Electronics and Information Materials School of Materials Science and Engineering Shanghai University Shanghai Yuking New Material Co. Ltd. Department of Light Chemical Engineering Sichuan Technology and Business College

Re（Re= Ce,Tb） doped lutetium oxyorthosilicate LuSiO（LSO） films were prepared by Pechini sol-gel method combined with modified spin-coating technique. The luminescent properties were analyzed by measuring the excitation and emission spectra in the VUV and UV. The results indicated that the Ce excitation bands in the region from 120-150 nm and 150-190 nm due to the host, and some weak peaks（230nm and 348nm） attributed to the 4f-5d transition of Ce. Tb excitation bands in the region from 150-170 nm were ascribed to the host and the region220-250 nm were due to the 4f-5d transitions of Tb. The emission spectra showed the characteristic emission D→F（J = 3, 4, 5, 6） for Tb and 5d-F（J=7/2,5/2） for Ce. Energy transfer from Ce to Tb in LSO:(Ce,Tb) thin films was observed and discussed carefully in the presented paper.

关键词： Lu2SiO5 films luminescence Ce3+-Tb3+energy transfer

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Research on occurrence characteristics of rare earth elements in carlin-type gold ore in the southwest of Guizhou province

Research on occurrence characteristics of rare earth element...

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第八届国际稀土开发与应用研讨会暨第三届中国稀土峰会

作者： Xianhai LI Qin ZHANG Zhihui SHEN Fei XIE Mining College Guizhou University National & Local Joint Laboratory of Engineering for Effective Utilization of Regional Mineral Resources from Karst Areas Guizhou Key Lab of Comprehensive Utilization of Non-metallic Mineral Resources Guizhou Engineering Lab of Effective Utilization of Regional Mineral Resources

There is abundant rare-earth element in our country, but it is very fragmented in the earth's crust, and it is very difficult to mining or mining cost is extremely high. There are few of industrial value rare earth deposits. There is a lot of concomitant rare earth deposits, and the comprehensive utilization value is *** is very rich carlin-type gold resource, associated with a certain amount of rare earth elements in the southwest of Guizhou Province. In order to utilize comprehensively this ore resources, this paper conducts the study on the occurrence characteristics of rare earth elements in the ore. By the chemical analysis, the gold grade is 3.35g/t, the organic carbon 0.81%, the total rare earth elements 0.022%,which is a high carbon fine disseminated gold ore. By the optical microscope and X-ray diffraction analysis(XRD) analysis, the major minerals are quartz, pyrite,calcite, limonite, arsenopyrite, mica, kaolinite, clay minerals, etc. In addition, there is a large amounts of carbonaceous materials, such as organic carbon, graphite, which is harmful on leaching of gold. By the scanning electron microscopy analysis, there are thorium, lanthanum and neodymium, ytterbium, persimmon and other rare earth elements in the ore. Gravity separation shows that rare earth elements enrich to lighter material mainly, which indicates that rare earth elements disseminate closely with lighter materials.

关键词： carlin-type gold ore Rare earth occurrence characteristics

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杭水：废水资源化技术助力稀土工业发展

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水工业市场 2016年第8期 35-35页

8月2-6日，第八届国际稀土发展与应用研讨会暨第三届中国稀土峰会在兰州召开。杭水是国内唯一在稀土行业拥有零排放业绩的水处理公司，受稀土协会邀请协办并参加了峰会，在大会中做了题为“Zero Discharge Technical For Rare Each Indu... 详细信息

8月2-6日，第八届国际稀土发展与应用研讨会暨第三届中国稀土峰会在兰州召开。杭水是国内唯一在稀土行业拥有零排放业绩的水处理公司，受稀土协会邀请协办并参加了峰会，在大会中做了题为“Zero Discharge Technical For Rare Each Industrial NH4Cl Waste Water”的主题报告，引起与会学者、专家，尤其是参会企业的关注，反响热烈。

关键词：稀土行业资源化技术工业发展废水 Industrial NH4Cl 主题报告水处理

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Effect of minor yttrium on mechanical properties and microstructure of die-casting magnesium alloy AZ91D

Effect of minor yttrium on mechanical properties and microst...

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第八届国际稀土开发与应用研讨会暨第三届中国稀土峰会

作者：徐玉磊张奎马鸣龙雷健 School of Materials and Metallurgy Inner Mongolia University of Science and Technology State Key Laboratory for Fabrication and Processing of Nonferrous Metals General Research Institute for Nonferrous Metals Material Technology Institute of BVTC Dong Feng Motor Co.LTD

Effects of yttrium(Y) addition in range of 0.05 wt.% to 0.35 wt.% on the microstructure and mechanical properties of die casting magnesium AZ91 D was investigated to improve mechanical properties of the alloy by scanning electron microscopy, X-ray diffraction and tensile tests. The results revealed that mechanical properties of die casting magnesium alloy AZ91 D with addition of yttrium was higher than those of die casting magnesium alloy AZ91 D at room temperature. The ultimate tensile strength, 0.2% proof yield strength and elongation to failure of die casting magnesium alloy AZ91 D at room temperature were 233 MPa, 198 MPa and 3.3%,respectively. In comparison, the ultimate tensile strength and elongation to failure of die casting magnesium alloy AZ91D-0.35%Y at room temperature reached to 283 MPa and 9.7%, respectively increased by 21% and 194% but the 0.2% proof yield strength of die casting magnesium alloy AZ91D-0.35%Y at room temperature reached to 184 MPa, decreased by 7%. Proper addition of yttrium can enhance the mechanical properties at an room temperature, which is attributed to the formation of Al-Y phases. Hence sliding of grain boundaries and cracks can be effectively hindered by Al-Y phases.

关键词： die casting magnesium alloy rare earth yttrium mechanical properties microstructure

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Geochemistry and Geologic Significance of Rare Earth Elements in Late Permian Coals from the Liupanshui Coalfield, Southwest China

Geochemistry and Geologic Significance of Rare Earth Element...

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第八届国际稀土开发与应用研讨会暨第三届中国稀土峰会

作者： CHENG Wei YE Junjian ZHANG Qin YANG Ruidong Mining College of Guizhou University National & Local Joint Laboratory of Engineering for Effective Utilization of RegionalMineral Resources from Karst Areas Guizhou University Guizhou Key Laboratory of Comprehensive Utilization of Non-metallic Mineral Resources College of Resources and Environmental Engineering Guizhou University

Rare earth elements(REEs) of fifty-eight Late Permian coal samples from Liupanshui Coalfield, western Guizhou of China, were determined by Inductively Coupled-plasma Mass Spectrometry(ICP-MS). The REE abundance, distribution and occurrence, as well as their geological significance were discussed. Analysis data shows that the total rare earth element contents(∑REE) varies considerably from13.56 to 347.36 μg/g(average 78.88 μg/g), higher than the average ∑REE in *** and the World coal, but lower than that of the Common Chinese Coal. We discussed the difference of REE distribution pattern types and found that chondrite-normalized patterns show clear consistence and inheritance from the source rock, Emeishan basalt. Variations of ∑REE, L/H and La N/Yb N were proved to have good correlations with coal-forming environments while δEu and δCe show certain indeterminacy. Since ∑REE in coal declines during the transgression period but rises during the regression, REE abundance can be regarded as a sensitive indicator for reversing the sea-level changes during the coal-forming period. Correlation coefficients analysis revealed that REE were partly associated with organic matters,and LREE has relatively stronger organic affinity than that of HREE, which could be largely attributed to the Lanthanide contraction, specifically the increasing ionization potentials.

关键词： rare earth geochemistry Late Permian coal Liupanshui sedimentary environment

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Study about the Characters of Rain on Soil Erosion

Study about the Characters of Rain on Soil Erosion

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第八届国际稀土开发与应用研讨会暨第三届中国稀土峰会

作者： SHEN Zhenzhou YAO Wenyi LI Zhanbin XIAO Peiqing LI Mian WEN Lipeng Xi′an University of Technology Key Laboratory of Soil and Water Loss Process and Control on the Loess Plateau MWR Yellow River Institute of Hydraulic Research Yan Shi Bureau of Land and Resources

In this paper, we adopted simulate rain experiment method to study the transformation of the change of raindrop speed and diameter with time and the results indicated that the rain intensity change strongly with time at the natural rainfall,However, the rain intensity was stability at simulate rainfall. At the natural rain, the raindrop speed mainly at 0.4-6.6m/s in different time, it have two wave crest were1m/s and 4.2m/s. However, at the simulate rain, the raindrop speed mainly at0.4-5.8m/s in different time, it has one wave crest was 1m/*** natural rain and simulate rain, the 0.125 mm diameter raindrop speed were about at 0.4-2.2m/s and0.4-5 m/s, the 0.25 mm diameter raindrop speed was about at 1-1.8m/s and0.4-4.2m/s, the 0.375 mm diameter raindrop speed was about at 1-2.2m/s and0.8-1.4m/s, the 0.5mm diameter raindrop speed was about at 1-3.4m/s and 1-3m/s,the 0.75 mm diameter raindrop speed was about at 3.4-4.2m/s and1.8-3.4m/s, the 1mm diameter raindrop speed was about at 3.4-4.2m/s and1.4-4.2m/s, the 1.25 mm diameter raindrop speed was about at4.2-5m/s and1.8-4.2m/s, the 1.5mm diameter raindrop speed was about at5m/s and 1.8-3.4 m/s.

关键词： natural rain simulate rain rain intensity rain amount

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Effect of rare earth La addition on microsture and properties of Mn-Cr-Mo bainite rail steels

Effect of rare earth La addition on microsture and propertie...

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第八届国际稀土开发与应用研讨会暨第三届中国稀土峰会

作者： Xirong BAO Jun'an WANG Xiaodong WANG Lin CHEN Yongzhen LIU Institute of Materials School of Materials Science and Engineering Shanghai University School of Material and Metallurgy Inner Mongolia University of Science and Technology School of Mining and Coal Inner Mongolia University of Science and Technology School of Materials Science &Engineering Inner Mongolia University of Technology

Three Mn-Cr-Mo bainite rail steels containing 0, 0.009 and 0.015 % La were prepared by the process of vacuum induction furnace smelting, forging and rolling. Effects of rare earth La on phase transformation, microstructure and substructure fining, and mechanical properties under different TMCP processes of rails were investigated by means of Johnson-Mehl-Avrami equation calculation,dilatometry, and metallography. The best alloy with excellent mechanical properties is that containing 0.009 % La, and the optimal TMCP process is explored *** show that the nanoscale bainite rail steels with RE, containing carbide-free bainite plate with a mean size smaller than 100 nm divided by stable residual austenites between subplates and subunits, could be produced by continuous cooling transformation around 480℃ at cooling rates from 0.8 to 2℃/s because RE can greatly enhance the hardenability of steel with Mn, Cr and Mo elements. The addition of RE in Mn-Cr-Mo bainite rail steels delays bainite transformation due to the combined retardation effect of RE and Cr, Mo on carbon diffusion. Moreover, RE addition facilitates the formation of bainite plate, refines substructures of bainitic ferrite by way of stimulating nucleation, and makes residual austenite be more stable which contributes to prevent the rail cracking by hindering crack propagation. In addition,two types of substructures can be found inside the bainite plates: ultra-fine micro-twins with various sizes of 2-20 nm and high density dislocation, which makes the tensile strength of test steel reach 1260 MPa and impact energy at room temperature up to 95 j.

关键词： bainite steel rare earth phase transformation substructure strengthening and toughening

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Fusion fuel gas storage characteristics on La activated ZrCo intermetallic

Fusion fuel gas storage characteristics on La activated ZrCo...

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第八届国际稀土开发与应用研讨会暨第三届中国稀土峰会

作者： Xia LI Ronghai YU Rongfeng LI Feng Wang College of material and metallurgy Inner Mongolia University of Science and Technology School of Materials Science and Engineering Beihang University

The Zr Co intermetallic is considered to be strategically important for deuterium/tritium fusion energy under development in International Thermonuclear Experimental Reactor(ITER), which is used for rapid and safe recovery/delivery of hydrogen isotopes. Here we report the structural, fast recovery and delivery properties and thermodynamic properties of La activated Zr Co using the first-principles approach and experimental study. The intermetallic compounds remains with single cubic phase identical with Zr Co by X-ray diffraction, and after La activated the lattice volume enlarged. The calculations are performed using a plane-wave based pseudo-potential approach under the framework of spin-polarized density-functional theory. From the total energy calculations, the enthalpy of formation of Zr Co H3 from Zr Co and Zr-La-Co are estimated to be 91 k J/mol H2 and 117 k J/mol H2 *** hydrogen recovery and delivery experimental indicated that the recovery rates illustrated to form hydrides of six different types of stoichiometry, and the delivery rate from those hydrides were in two-order of magnitude in 10 min. Hydrogen desorption pressure-composition-temperature(PCT) measurements were carried out using Sievert's type volumetric apparatus and the hydrogen desorption pressure-composition isotherms(PCIs) were generated for all the alloys in the temperature range of 523 K, 573 K, 623 K and 673 K. A van't Hoff plot was constructed using plateau pressure data of each pressureecomposition isotherm and the thermodynamic parameters were calculated for desorption of hydrogen in the Zr-La-Co systems. Both lattice parameters and enthalpy and entropy change for desorption of hydrogen are found to be in good agreement with their corresponding experimental values. Disproportionation in the Zr Co–hydrogen system was confirmed to be very sensitive at a higher temperature(>350 ℃) and a higher hydrogen pressure(>3.1 k Pa). However, La activated Zr Co intermetallic compounds dura

关键词： Zr Co intermetallic Hydrogen isotopes storage first-principles calculation enthalpy

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Recovery of Rare Earth Elements(REEs) from Pregnant Leach Solution of Apatite through Precipitation

Recovery of Rare Earth Elements(REEs) from Pregnant Leach So...

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第八届国际稀土开发与应用研讨会暨第三届中国稀土峰会

作者： Batnasan ALTANSUKH Kazutoshi HAGA Battsengel ARIUNTUYA Yasushi WATANABE Atsushi SHIBAYAMA Faculty of International Resource Sciences Graduate School of International Resource Sciences Akita University Faculty of Engineering Science Graduate School of Engineering and Resource Science Akita University

Apatite is an important host mineral in igneous and metamorphic rocks for production of phosphate fertilizers and phosphoric acid. Deposits of apatite ores are the major source for rare earth elements（REEs） because almost all apatite contains these *** this study, apatite deposit associated with rare earth elements was treated with different concentrations of sulfuric acid（HSO） solutions under varying conditions for the formation of pure gypsum and extraction of the vast majority of REEs as by product.X-ray diffraction（XRD） analysis identified fluorapatite in apatite deposit, gypsum（Ca SO × 2HO） and bassanite/hemigypsum（Ca SO × 0.5HO） in the residues obtained from leaching with dilute and high concentration of sulfuric acid solutions. The Ca O and SO contents of gypsum and bassanite formed were 32.1 %, 45.0 % and 30.0%,25.1% when the apatite contains Ca O and SO in amounts of 29.7 mass% and 1.4mass%. Main impurities in the solid residues were fluorine（F）, Si O, Sr O, Al2O3 and Mg O. Over 90 % of uranium（U）, 80 % of thorium（Th） and 82 % of REEs were leached in a dilute sulfuric acid solution under the optimized conditions. On the other hand, 70-80 % U, Th and REEs lost in the solid residue when high concentration of sulfuric acid is involved. The pregnant leach solution containing high concentrations of REEs was purified by precipitation to recover REEs. Various precipitating agents,particularly sodium hydroxide（Na OH）, sodium carbonate（NaCO） and oxalic acid（CHO） with concentrations from 0.5 to 10 %（w/v） were added to the pregnant leach solution. Results showed that the vast majority of REEs（> 99 %） precipitated from the leachate by using 5 % oxalic acid, while highly efficient precipitation of REEs was achieved by 10 % Na OH and NaCO, respectively.

关键词： fluorapatite gypsum bassanite rare earth elements leaching precipitation

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A Novel Green Process for Baotou Rare Earth Ores metallurgy and Separation——a process of rare earths leaching and extraction separation in sulfuric acid system with magnesium bicarbonate solution, as well as magnesium salt wastewater recycling

A Novel Green Process for Baotou Rare Earth Ores metallurgy ...

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第八届国际稀土开发与应用研讨会暨第三届中国稀土峰会

作者： Huang Xiaowei Feng Zongyu Wang Meng Xu Yang Yi Shuai Cui Dali Xia Chao GRIREM Advanced Material Co. Ltd National Engineering Research Center for Rare Earth MaterialsGeneral Research Institute for Nonferrous Metals

Baotou mixed rare earth ores are mainly treated with sulphuric acid method,including sulfatizing roasting, leaching with water, extracting with HDEHP or HEH/EHP. A large amount of magnesium oxide powder are used to neutralize the residual acid and impurities removal, which not only brought with a great deal of magnesium sulfate wastewater, but also aluminum, iron and other impurities into extraction system, The former, containing calcium ions, is easy to form calcium sulfate deposit which will block pipeline and equipment, meanwhile the latter is easy to extract concentration which will greatly affected the rare earth extraction capacity and product quality. To solve the above problems, GRIREM has successfully developed a novel green technology for Baotou rare earth ores hydrometallurgy and separation. The pure magnesium bicarbonate solution can be efficiently and continuously prepared with magnesium sulfate wastewater and carbon dioxide recycled from the process, which could replace the solid magnesium oxide in sulfatizing roasting ore leaching,neutralization and impurity removal, extraction transformation and separation. The recycling rate of magnesium and carbon dioxide during extraction of rare earths are above 90% and 95%, ***, the novel technology is running in 30,000 ts rare earth concentrates processing line in Gansu rare earth new material Co., Ltd.. The first-stage project has been achieved in continuous stable operation, including magnesium bicarbonate solution preparation, rare earth extraction and separation with magnesium bicarbonate solution, and magnesium sulfate wastewater and carbon dioxide recycling. Moreover,low-carbon, low-salt as well as no ammonia nitrogen emissions could be achieved in the process, which will greatly reduce environmental protection investment and production cost, and rare earths environment-friendly and efficient production could been realized.

关键词： Baotou rare earth ore magnesium bicarbonate extraction and separation recycling of wastewater and carbon dioxide

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