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Carbide refinement in M42 high speed steel by rare earth metals and spheroidizing treatment 被引量:2
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作者 周雪峰 方峰 +3 位作者 涂益友 蒋建清 朱旺龙 尹松艳 《Journal of Southeast University(English Edition)》 EI CAS 2014年第4期445-448,共4页
The influence of rare earth metals and heat treatment on the microstructure and performance of M42 steel has been investigated by means of an optical microscope OM scanning electron microscope SEM energy dispersive sp... The influence of rare earth metals and heat treatment on the microstructure and performance of M42 steel has been investigated by means of an optical microscope OM scanning electron microscope SEM energy dispersive spectroscopy EDS transmission electron microscope TEM electron back-scatter diffraction EBSD and X-ray diffraction XRD . The results show that M2 C is the prevailing type of eutectic carbides in M42 steel. After modification with rare earth metals M2 C eutectic carbides change from the ordered lamellar structure into a circular structure.Despite different morphologies the two carbides present the same characteristics of microstructure and growth orientation.Compared with lamellar carbides M2 C carbides with the circular structure are much easier to decompose and spheroidize after heating which remarkably refines the carbide dimensions.The refined carbides improve the supersaturation of alloying elements in martensite and increase the hardness of M42 steel by 1.5 HRC. 展开更多
关键词 high speed steel rare earth metals carbide dimension SPHEROIDIZATION
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Some New Results from the Electron Theory on the Elastical of Alkahoe Earth Metals and Rare Earth Elements
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作者 崔秀山 邢胜娣 《Journal of Beijing Institute of Technology》 EI CAS 1994年第1期31+26-32,共8页
With the introduction of Poisson's ratio in the expression of Young's modulus,nearly all the theoretical values of the various elastic moduli for the alkaline earth metals and rare earth elements can be greatl... With the introduction of Poisson's ratio in the expression of Young's modulus,nearly all the theoretical values of the various elastic moduli for the alkaline earth metals and rare earth elements can be greatly refined, with the single exception of the theoreticalvalue of Young's modulus for Pr which is slightly increased This points to the validityof the new theory, that the bulk modulus is independent of the Poisson's ratio, and further that the valency electron structures of solids as determined by Yu's theory are correct. 展开更多
关键词 alkaline earth metals rare earth elements/electron theory of elasticity
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Analysis of Different Rare Metals, Rare Earth Elements, and other Common Metals in Groundwater of South West Bank/Palestine by ICP/MS-Data and Health Aspects 被引量:1
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作者 Fuad Al-Rimawi Khalid Kanan Mutaz Qutob 《Journal of Environmental Protection》 2013年第10期1157-1164,共8页
Ground water samples are collected from south West Bank/Palestine and analyzed for different rare elements (Rb, Zr, U, P, Ti, V), rare earth elements (La, Ce, and Nd), and other common trace metals (Li, Na, Mg, Ca, Sr... Ground water samples are collected from south West Bank/Palestine and analyzed for different rare elements (Rb, Zr, U, P, Ti, V), rare earth elements (La, Ce, and Nd), and other common trace metals (Li, Na, Mg, Ca, Sr, Ba, K, Bi) that most of them usually have no maximum acceptable limits as either they are considered not to be toxic to human health or there is no sufficient data about their toxicity to human health. This study was conducted to determine the water quality of ground water which is used for drinking in the study area. Water samples from ten groundwater wells were obtained in three different dates of the year (November 2012, March 2013, and April 2013). Three water samples were obtained from each well for each sampling date;so a total of 90 water samples were collected from the ten wells. The results obtained from this study suggest a possible risk to the population of the study area given the high concentration of some metals that have no maximum allowed concentration, and the fact that for many people in the study area, ground water is a main source of their water supply. 展开更多
关键词 rare metals rare earth Elements WHO Limits ICP/MS Ground Water West BANK
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Analysis of Different Rare Metals, and Rare Earth Metals in Harvested Rain Water in Gaza Strip/Palestine by ICP/MS-Data and Health Aspects 被引量:1
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作者 M. A. Al-Qutob F. Al-Rimawi 《Journal of Water Resource and Protection》 2016年第10期905-912,共8页
This rain water samples harvested for drinking and agriculture from Gaza collected in November 2012 were analyzed for different rare metals (Rb, Zr, Ti, Tl, Sb, Sc, Y), and rare earth metals (La, and Ce). These metals... This rain water samples harvested for drinking and agriculture from Gaza collected in November 2012 were analyzed for different rare metals (Rb, Zr, Ti, Tl, Sb, Sc, Y), and rare earth metals (La, and Ce). These metals usually have no maximum acceptable limits as there is no sufficient data about their toxicity to human health. Their control should be therefore controlled in water to monitor their concentration in water (ground, harvested, etc.). This study was conducted to determine the water quality of harvested water which is used for drinking in the study area. 43 water samples were collected in November 2012 during the first rain from house wells and rain water pools. The concentrations of the metals detected in the collected harvested rainwater vary significantly between the 43 samples, and all of them were detected in all water samples analyzed in this study. The results obtained from this study suggest a possible risk to the population of the study area given the high concentration of some metals that have no maximum allowed concentration, and the fact that for many people in the study area, harvested rain water is a main source of their water supply. 展开更多
关键词 rare metals rare earth Elements WHO Limits ICP/MS Gaza Strip Harvested Rain Water
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EFFECTS OF RARE EARTH METALS ON MICROSTRUCTURAL TRANSFORMATION OF LOW OR MEDIUM CARBON Si-Mn-V STEELS DURING QUENCHING AND TEMPERING
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作者 WANG Xiaotian YAO Yinliang SHAO Tanhua Xi′an Jiaotong University,Xi′an,China 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1991年第3期188-193,共6页
The microstruetural transformation of steels:20SiMn2V,20SiMn2VRE,40SiMn2V and 40SiMn2VRE during quenching and tempering have been examined by TEM,X-ray diffraction and dilatometer.It was shown that the addition of rar... The microstruetural transformation of steels:20SiMn2V,20SiMn2VRE,40SiMn2V and 40SiMn2VRE during quenching and tempering have been examined by TEM,X-ray diffraction and dilatometer.It was shown that the addition of rare earth metals not only can refine the austenite grains of the low or medium carbon steels and packet of lath martensite and lath size,lower the M_s temperature,but can also raise the relative percentage of disloca- tion substructure of martensite in medium carbon steel,but there is little effect on volume frac- tion and thermal stability of retained austenite quenching and tempering structure of low or medium carbon steels.The rare earth metals may remarkably inhibit the decomposition of low carbon martensite during low temperature tempering,retard the precipitation of cementite plates in lath grains and delay the spheroidization of carbides.They may also restrain obvious- ly the precipitation and spheroidization of cementite in medium carbon martensite during high temperature tempering. 展开更多
关键词 rare earth metals TEMPERING SiMnV steel microstrueture
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A Brief Introduction to the Rare Earths Research Institute,General Research Institute for Non-Ferrous Metals
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《Journal of Rare Earths》 SCIE EI CAS CSCD 1993年第3期227-229,共3页
The Rare Earths Research Institute(the former Rare Earths Research Laboratory)under the GRINM,the first institute to conduct R&D for rare earths(RE)industry in China,was founded in 1958.The Institutewas mainly eng... The Rare Earths Research Institute(the former Rare Earths Research Laboratory)under the GRINM,the first institute to conduct R&D for rare earths(RE)industry in China,was founded in 1958.The Institutewas mainly engaged in the research work of comprehensive utilization of the mine at Baiyun-ebo,the largest 展开更多
关键词 In A Brief Introduction to the rare earths Research Institute General Research Institute for Non-Ferrous metals RE
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Electron Donating Property and Catalytic Activity ofPerovskite-type Mixed Oxides (ABO_3) Consisting of Rare Earth and 3d Transition Metals
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作者 S.Sugunant and V.Meera(Dept. of Applied Chemistry, Cochin University of Science and Technology, Kochi-682022, India) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1995年第3期229-231,共3页
The catalytic activity of Perovskite-type mixed oxides (LaCoO3, PrCoO3 and SmCoO3) for the reduction of cyclohexanone to cyclohexanol with 2-propanol (Meerwein-PonndorfVerley reduction) has been studied. The data have... The catalytic activity of Perovskite-type mixed oxides (LaCoO3, PrCoO3 and SmCoO3) for the reduction of cyclohexanone to cyclohexanol with 2-propanol (Meerwein-PonndorfVerley reduction) has been studied. The data have been correlated with the surface electron donor properties of these mixed oxides 展开更多
关键词 Activity type ABO3 Consisting of rare earth and 3d Transition metals Electron Donating Property and Catalytic Activity ofPerovskite-type Mixed Oxides
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A Brief Introduction to the Rare Earths Research Institute,General Research Institute for Non-Ferrous Metals
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《Journal of Rare Earths》 SCIE EI CAS CSCD 1993年第4期308-310,共3页
The Rare Earths Research Institute(the former Rare Earths Research Laboratory)under the GRINM,the first institute to conduct R&D for rare earths(RE)industry in China,was founded in 1958.The Institutewas mainly eng... The Rare Earths Research Institute(the former Rare Earths Research Laboratory)under the GRINM,the first institute to conduct R&D for rare earths(RE)industry in China,was founded in 1958.The Institutewas mainly engaged in the research work of comprehensive utilization of the mine at Baiyun-ebo,the largestRE mine in the world,and the ion adsorption type RE mineral in southern China.The ore decomposition, 展开更多
关键词 In A Brief Introduction to the rare earths Research Institute General Research Institute for Non-Ferrous metals REC
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Infrared Polarizabilities of 3d-Transition and Rare-Earth Metals
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作者 Kofi Nuroh 《Journal of Modern Physics》 2018年第2期287-301,共15页
A transition or rare-earth metal is modeled as the atom immersed in a jellium at intermediate electron gas densities specified by? rs=4.0. The ground states of the spherical jellium atom are constructed based on the H... A transition or rare-earth metal is modeled as the atom immersed in a jellium at intermediate electron gas densities specified by? rs=4.0. The ground states of the spherical jellium atom are constructed based on the Hohenberg-Kohn-Sham density-functional formalism with the inclusion of electron-electron self-interaction corrections of Perdew and Zunger. Static and dynamic polarizabilities of the jellium atom are deduced using time-dependent linear response theory in a local density approximation as formulated by Stott and Zaremba. The calculation is extended to include the intervening elements In, Xe, Cs, and Ba. The calculation demonstrates how the Lindhard dielectric function can be modified to apply to non-simple metals treated in the jellium model. 展开更多
关键词 INFrareD Polarizability JELLIUM TRANSITION metals rare-earth metals Electron SELF-INTERACTION Correction
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Neutron Diffraction Study of Self-Curing and Self-Crystallization Phenomena of Low-Temperature Dehydrogenating Products of Powder Crystals of Rare-Earth Metals Trihydroxides
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作者 Khidirov Irisali 《Journal of Crystallization Process and Technology》 2013年第4期156-162,共7页
The phenomenon of hydrogen thermoemission out of a crystal lattice of powder rare-earth metals trihydrooxides R(OH)3 (R is La, Pr, Nd) was found. The hydrogen thermoemission out of a crystal lattice is partial or full... The phenomenon of hydrogen thermoemission out of a crystal lattice of powder rare-earth metals trihydrooxides R(OH)3 (R is La, Pr, Nd) was found. The hydrogen thermoemission out of a crystal lattice is partial or full removal of hydrogen out of the crystal lattice of powder hydrogen-containing crystal without change of symmetry of such crystal at continuous evacuation of high vacuum at evacuation temperature of Тev. which is lower than recrystallization Тrecrys. or disintegration (Tdisinteg.) temperature of this crystal: Тev. Тrecrys. Tdisineg.. By neutron diffraction it is found that low- temperature (Тevacuation = 400 - 420 K ) removal of hydrogen (by hydrogen thermoemission) out of a crystal lattice of trihydrooxide R(OH)3 under continuous high vacuum evacuating makes possible to obtain metastable “trioxide” R[O]3. Existence of such substance contradicts to the valence law (oxygen is bivalent and Pr is trivalent in hydroxides). Such “trioxide” has a superfluous negative charge: R3+O6-. So they aspire to “capture” three more protons (hydrogen ions) from a water molecules. Obviously, this substance can be stable at low temperatures and in the mediums, which are not containing hydrogen. In the air at room temperature this substance, most likely, interacting with water molecules, gradually again turns into trihydroxide R(OH)3, compensating the superfluous negative charge by three hydrogen atoms. From this it follows that substance R[O3] can simultaneously be an absorber of hydrogen and generator of oxygen at atmospheric conditions and in any mediums which contains water molecules, without any prior processing like heating or high pressure. Thus, the obtained material, without any prior processing like heating or high pressure, can simultaneously be oxygen generator and hydrogen accumulator in any mediums characteristic of R[O3] to transform into stable form R(OH)3 by selective bonding of hydrogen from the hydrogen-containing environment allowing implication of Pr[O3] as the hydrogen selective absorber. Separation (by low-temperature removal) of hydrogen out of R(OH)3 lattice can again lead to restoration of its capabilities to be a simultaneous hydrogen accumulator and oxygen generator in a medium containing water molecules. 展开更多
关键词 Hydrogen Termoemission rare-earth metals Trihydrooxides Neutron Diffraction High Vacuum Continuous EVACUATION METASTABLE “Trioxide” R[O3]
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Rare Metals (Ta-Nb-Sn) Mineralization Potential of Pegmatites of Igangan Area, Southwestern Nigeria
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作者 Olusegun G. Olisa Olugbenga A. Okunlola Ayotunde A. Omitogun 《Journal of Geoscience and Environment Protection》 2018年第4期67-88,共22页
The study was carried out to determine the rare metal mineralization potential of some pegmatites associated with metasediments in the Igangan 240 NW sheet. Geological mapping on a scale of 1:50,000 revealed the pegma... The study was carried out to determine the rare metal mineralization potential of some pegmatites associated with metasediments in the Igangan 240 NW sheet. Geological mapping on a scale of 1:50,000 revealed the pegmatites intrude metasediments and geochemical analysis for major, trace and rare earth elements were carried out using ICP MS/AES. Petrographic studies reveal a mineral assemblage of quartz, microcline and tourmaline;SEM studies revealed garnet and tourmaline to be close to the spessartine end-member and schorl respectively with albite occurring as the dominant plagioclase feldspar in the pegmatites. Result of geochemical analysis revealed SiO2 with an average of 73.91% in the whole rock pegmatite Al2O3 with an average of 13.93%, and average concentration of 0.57%, 4.3% and 4.77% for CaO, Na2O and K2O respectively. It also revealed average concentration of 29 ppm, 153 ppm, 30 ppm, 118 ppm and 129 ppm for W, Li, Ta, Nb and Sn in the mica respectively which is above the average values in the whole rock, felspars and tourmaline extracts. REE abundance in the whole rock pegmatites is low to moderate with ∑REE varying between 8 - 220 ppm, 2 - 23 ppm in feldspars and 3 - 32 ppm in mica signifying no form of REE enrichment. Geochemical analysis results and trace elemental plots such as K/Rb vs. Rb, Ta vs. Ga, Ta vs. Cs were used to assess rare metal mineralization and it revealed the pegmatites have low level of rare metal and rare earth element mineralization with average k/Rb values of 177 indicative of low fractionation levels in the pegmatites. 展开更多
关键词 rare metals MINERALIZATION rare earth Elements PEGMATITES
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Prediction of Surface Tensions of Pure Liquid Metals and Alloys
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作者 严丽君 谢允安 +1 位作者 邢献然 乔芝郁 《Journal of Rare Earths》 SCIE EI CAS CSCD 1999年第3期182-188,共7页
The surface tensions of pure liquid metals were estimated by using the artificial neural network method. Based on Butler's equation the surface tensions of some liquid Sn-, Ag-, Cu-based binary alloys were calcula... The surface tensions of pure liquid metals were estimated by using the artificial neural network method. Based on Butler's equation the surface tensions of some liquid Sn-, Ag-, Cu-based binary alloys were calculated from surface tensions of pure components and thermodynamic parameters of liquid alloys using a well designed computer program with C++ language, named STCBE. The agreement between calculated values and experimental data was excellent. The surface tensions of binary liquid Cu-RE(RE: Ce, Pr, Nd) alloys at 1400 K were predicted therewith. 展开更多
关键词 rare earths surface tension neural network liquid metals liquid alloys
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Using Atomic Microstates and Atomic Number Parity in Support of Lutetium and Lawrencium Classification as Transition Metals
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作者 Valery Tsimmerman 《Journal of Chemistry and Chemical Engineering》 2018年第3期92-95,共4页
Unlike other groups of elements, Group 3 constituency remains unsettled. This article argues that ground level microstates and atomic number parity suggest Sc-Y-Lu-Lr Group 3 membership.
关键词 TRANSITION metals inner TRANSITION elements lawrencium placement rare earth metals group 3 constituents ground level ATOMIC microstates ATOMIC number PARITY f-block.
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Comparison of extraction abilities of deep eutectic solvents and aqueous acid solutions for extraction of rare earths and transition metals
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作者 Svetlana Drogobuzhskaya Margarita Frolova +1 位作者 Andrey Shishov Nikita Tsvetov 《Journal of Rare Earths》 SCIE EI CAS CSCD 2024年第6期1157-1164,I0006,共9页
In recent years,deep eutectic solvents have attracted increasing interest as effective extractants for the separation of both organic substances and metals from various objects.Acid-based deep eutectic solvents are mo... In recent years,deep eutectic solvents have attracted increasing interest as effective extractants for the separation of both organic substances and metals from various objects.Acid-based deep eutectic solvents are most often used as extractants for the extraction of metals.In this work,for the first time,the extraction efficiency of transition metals and rare earth elements(Y,Zr,Nb,La,Ce,Pr,Nd,Sm,Eu,Gd,Tb,Dy,Ho,Er,Tm,Yb,Lu,Hf and Ta)from mining tailings and Na,K,Ca,Mg,Cu,Fe,Mn,Pb,Ba,Ni and Sr from biodiesel samples using acidic deep eutectic solvents and saturated aqueous solutions of the same acids(malonic,malic,tartaric and citric)is compared.For this,deep eutectic solvents based on acids and their aqueous saturated solutions were prepared and studied.The prepared mixtures were analyzed by IR spectroscopy to confirm the formation of eutectic solvents.Properties such as the density and viscosity of the resulting mixtures were also investigated,as this can be of key importance for the efficiency of metal extraction.The extraction of rare earth metals from mining tailings took a long time(up to several days),while the extraction of metals from fuel took no more than 30 min.Atomic emission spectral methods were used as an analysis method.It is shown that the extraction efficiency with aqueous solutions is better than that with eutectic solvents,which casts doubt on the need for deep eutectic solvents use in this area. 展开更多
关键词 Deepeutectic solvent metal separation Elemental analysis rare earth metals BIODIESEL
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Extraction of metals from complex sulfide nickel concentrates by low-temperature chlorination roasting and water leaching 被引量:8
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作者 Cong Xu Hong-wei Cheng +4 位作者 Guang-shi Li Chang-yuan Lu Xiong-gang Lu Xing-li Zou Qian Xu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2017年第4期377-385,共9页
The recovery of valuable metals from complex sulfide concentrates was investigated via chlorination roasting followed by water leaching. A reaction process is proposed on the basis of previous studies and the results ... The recovery of valuable metals from complex sulfide concentrates was investigated via chlorination roasting followed by water leaching. A reaction process is proposed on the basis of previous studies and the results of our preliminary experiments. During the process, various process parameters were studied, including the roasting temperature, the addition of NH4Cl, the roasting time, the leaching time, and the liquid-to-solid ratio. The roasted products and leach residues were characterized by X-ray diffraction and vibrational spectroscopy. Under the optimum condition, 95% of Ni, 98% of Cu, and 88% of Co were recovered. In addition, the removal of iron was studied in the water leaching stage. The results demonstrate that this process provides an effective approach for extracting multiple metals from complex concentrates or ores. © 2017, University of Science and Technology Beijing and Springer-Verlag Berlin Heidelberg. 展开更多
关键词 CALCINATION Chemicals removal (water treatment) CHLORINATION LEACHING metal recovery Nickel rare earths Sulfur compounds Temperature X ray diffraction
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Recovery of rare earth metals through biosorption: An overview 被引量:25
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作者 Nilanjana Das Devlina Das 《Journal of Rare Earths》 SCIE EI CAS CSCD 2013年第10期933-943,共11页
Rare earth metals (REMs) are a series of 17 elements that have widespread and unique applications in high technology, power generation, communications, and defense industries. These resources are also pivotal to eme... Rare earth metals (REMs) are a series of 17 elements that have widespread and unique applications in high technology, power generation, communications, and defense industries. These resources are also pivotal to emergent sustainable energy and car- bon alternative technologies. Recovery of REMs is interesting due to its high market prices along with various industrial applications. Conventional technologies, viz. precipitation, filtration, liquid-liquid extraction, solid-liquid extraction, ion exchange, super critical extraction, electrowinning, electrorefining, electroslag ref'ming, etc., which have been developed for the recovery of REMs, are not economically attractive. Biosorption represents a biotechnological innovation as well as a cost effective excellent tool for the recovery of rare earth metals from aqueous solutions. A variety ofbiomaterials such as algae, fungi, bacteria, resin, activated carbon, etc., have been reported to serve as potential adsorbents for the recovery of REMs. The metal binding mechanisms, as well as the parameters in- fluencing the uptake of rare earth metals and isotherm modeling are presented here. This article provides an overview of past achievements and current scenario of the biosorption studies carried out using some promising biosorbents which could serve as an economical means for recovering REMs. The experimental findings reported by different workers will provide insights into this re- search frontier. 展开更多
关键词 BIOSORPTION BIOSORBENT DESORPTION rare earth metals RECOVERY
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Liquid-liquid extraction and separation of total rare earth(RE) metals from polymetallic manganese nodule leaching solution 被引量:14
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作者 P.K.Parhi K.H.Park +1 位作者 C.W.Nam J.T.Park 《Journal of Rare Earths》 SCIE EI CAS CSCD 2015年第2期207-213,共7页
The study on the solvent extraction for quantitative and selective separation of total rare earth metals from the polymetallic nodule leach liquor was investigated. The typical leach liquor bearing 0. 094 g/L total ra... The study on the solvent extraction for quantitative and selective separation of total rare earth metals from the polymetallic nodule leach liquor was investigated. The typical leach liquor bearing 0. 094 g/L total rare earth, 0. 23 g/L Mn, 0.697 g/L Cu, 0.2 g/L Fe, 0.01 g/L Co and 0.735 g/L Ni was subjected to the removal iron content by precipitation method using Ca(OH)2 at pH 3.95, prior to solvent extraction of rare earth metals. Three different organo-phosphoric acid reagents(D2EHPA, PC88 A, Cyanex 272) were used to ascertain their performances and selectivity towards the loading of rare earth metals in presence of other base metals. Based on the results of eq. pH effect, the performances of above three extractants followed the order as: D2EHPA〉PC88A〉Cyanex 272. To ensure the absence of extraction of base metals(Cu, Co, Ni), the eq. pH of the solution was optimized at the level of 2.21, though higher rare earth metal extraction efficiency was observed at higher eq. pH with either of the extractants. The complete process flow diagram for substantial recovery of total rare earth was developed using D2 EHPA. Extraction isotherm plot was constructed at A:O=12:1, 3-stages and pHe=2.21, using 0.8 mol/L D2 EHPA and the predicted condition of this study was further confirmed by 6-Cycles Counter Current Simulation(CCS) study. The stripping of total rare earth from loaded organic phase(LO) was conducted using HCl solution. Mc-Cabe Thiele diagram study carried out at A:O=1:5 using 4 mol/L HCl showed that three theoretical stages were needed for quantitative stripping of total rare earth. The subsequent stripped solution resulted thus led to contain total rare earth of 5.6 g/L indicating a very high enrichment of total metals by solvent extraction(SX) process. 展开更多
关键词 total rare earth (RE) metals SX D2EHPA HCl deep sea nodule
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Rare earth metals sorption recovery from uranium in situ leaching process solutions 被引量:7
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作者 N.M.Shokobayev C.Bouffier T.S.Dauletbakov 《Rare Metals》 SCIE EI CAS CSCD 2015年第3期195-201,共7页
Sorption characteristics of ion exchange resins 001 × 7, 005 × 8, D72 regarding rare earth metals (REM) during extraction from barren solution of uranium sorption in dynamic conditions were investigated. I... Sorption characteristics of ion exchange resins 001 × 7, 005 × 8, D72 regarding rare earth metals (REM) during extraction from barren solution of uranium sorption in dynamic conditions were investigated. It was identified that D72 resin capacity on analyzed REM was 2.46 mg.cm-3 after passing 220 BV (bed volume) of initial solution with 95 % recovery of element of REM with the lowest affinity. Researches on REM desorption in dynamic conditions from investigated ion exchange resins by solution of 1.7 mol.L-1 HNO3 and 8.0 mol.L-1 NHnNO3 with 0.2 mol.L-1 HNO3 passing were carded out. It was identified that using desorption solution based on ammonium nitrate allows to achieve acceptable recovery degree of REM from the resin. The possibility of organization of a circulating desorption solution system increases the perspectives of nitrate ammonium solution usage. 展开更多
关键词 Uranium in situ leaching SORPTION Co-recovery rare earth metals
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Evolution and deformability of inclusions in Al-killed steel with rare earth-alkali metals(Ca or Mg) combined treatment 被引量:2
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作者 Yeguang Wang Chengjun Liu 《Journal of Rare Earths》 SCIE EI CAS CSCD 2023年第9期1459-1466,I0007,共9页
The quality of stainless steel is closely related to the deformability of inclusions,which is significantly affected by their compositions.The present study first inve stigated the evolution of inclusion compositions ... The quality of stainless steel is closely related to the deformability of inclusions,which is significantly affected by their compositions.The present study first inve stigated the evolution of inclusion compositions in AI-killed steel with rare earth-alkali metals(Ca or Mg)combined treatme nt through four laboratory-scale experiments.The Ce contents in the final steel are 0.0080 wt%,0.015 wt%,0.016 wt%and 0.010 wt%,respectively.The Mg content is 0.0014 wt%in Ce-Mg combined treated steel,and the Ca content is0.0015 wt%in Ce-Ca combined treated steel.The deformability of inclusions in both Ce_(2)O_(3)-Al_(2)O_(3)-CaO and Ce_(2)O_(3)-Al_(2)O_(3)-MgO systems was subsequently evaluated by calculating their Young's modulus at low temperature.The results show that irregular Al_(2)O_(3)and MgAl_(2)O_(4)with poor deformability are modified to CeAlO_(3)and Ce_(2)O_(3)by Ce treatment,resulting in the decrease of Young's modulus of inclusions.The deformability of inclusions is further improved due to the transformation from lumped-like CeAlO_(3)to spherical CaO-Al_(2)O_(3)-Ce_(2)O_(3)caused by Ca treatment,and some of these inclusions are the ones with low liquidus temperature.Thermodynamic analysis was used to discuss the control condition of the formation and evolution of inclusions.Accordingly,the appropriate addition amounts of Al,Mg,Ce,and Ca are expected to control inclusion compositions and properties,including deformability and liquidus temperature,thereby improving the steel performance. 展开更多
关键词 rare earths Alkali metals Inclusions evolution Inclusions deformability Thermodynamic analysis
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Recovery of rare-earth metals from aqueous solutions by bio/adsorption using non-conventional materials:a review with recent studies and promising approaches in column applications 被引量:13
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作者 Talles Barcelos da Costa Meuris Gurgel Carlos da Silva Melissa Gurgel Adeodato Vieira 《Journal of Rare Earths》 SCIE EI CAS CSCD 2020年第4期339-355,共17页
The recovery of rare-earth metals(REMs)is of great economic and environmental interest,because of their high market prices and various industrial applications.Recently,with the increasing demand for high-purity rare-e... The recovery of rare-earth metals(REMs)is of great economic and environmental interest,because of their high market prices and various industrial applications.Recently,with the increasing demand for high-purity rare-earth compounds,the separation and purification of these elements have gained considerable attention.The bio/adsorption process has been considered an alternative to recover these elements,by its simplicity,low cost and efficiency for recovery of REMs at low concentrations.This review article presents the recent progress regarding REM bio/adsorption published literature in batch system by different non-conventional bio/adsorbents,as well as a critical analysis of the technological challenges to be faced and future prospects.For this purpose,the best application model(isotherm,kinetics),thermodynamic quantities and selection of eluents for desorption studies are also discussed.Additionally,in this review,the application of different bio/adsorbent materials were reviewed extensively in terms of the removal and recovery of REMs in continuous fixed-bed adsorption and regeneration cycles.Finally,future aspects in bio/adsorption research and prospects for commercial applications were discussed. 展开更多
关键词 rare-earth metals Bio/adsorbents ADSORPTION kinetics ISOTHERM Batch desorption Continuous FIXED-BED ADSORPTION
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