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用稀土皂化有机相技术在轻稀土分离工艺中的新应用 总被引:2,自引:0,他引:2
采用P_(204)萃取剂,氮化轻稀士为原料,应用稀土皂化有机相技术,连续、稳定地生产出99~99.5%的Nd_2O_3、镧铈谱富集物及部分99~99.5%La_2O_3。且富集物LaCePr溶液稀土浓度提高了2~3倍,使下步工序的Ce-pr、La-Ce分离段,在相同设备、萃取参数条件下,较原设计工艺提高处理量近50%。 相似文献
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高碱度控制氧位渣系(BaO—BaCl2—Cr2O3)对含铬铁水选择氧化脱磷影响的研究 总被引:3,自引:0,他引:3
在实验室条件下,以小渣量研究了BaO-BaCl2(或BaF2)-Cr2O3系脱磷剂对高铬铁水脱磷时,脱磷剂中溶剂(BaCl2和BaF2),氧化剂(Cr2O3和Fe2O3),渣量,铁液中原始〔%C〕和〔%Si〕,以及温度对脱磷率的影响。 相似文献
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纳米晶Fe_3B/Nd_2Fe_(14)B粘结永磁体的磁性能研究 总被引:4,自引:0,他引:4
本文研究了粘结剂含量和温度-时间变化对纳米晶Fe3B/Nd2Fe14B粘结永磁材料的磁性能影响。结果表明降低粘结剂含量可显著地提高纳米晶Fe3B/Nd2Fe14B粘结永磁的磁性能;环境温度对纳米晶Fe3B/Nd2Fe14B粘结永磁的磁性能具有重要影响,在较高的温度下其磁性能将显著下降,因此纳米晶Fe3B/Nd2Fe14B粘结永磁只能在较低的温度环境下使用 相似文献
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氟碳铈矿热分解行为的研究 总被引:10,自引:0,他引:10
采用XRD法分析了不同温度下氟碳铈矿焙烧分解产物的组成,探讨了氟碳铈矿的热分解过程。试验结果表明氟碳铈矿的热分解是分步进行的。首先(Ce,La)CO3F分解成(Ce,La)OF;升高焙烧温度,(Ce,La)OF发生相分解,生成Ce0.75Nd0.25O1.875和(Ce,Pr)La2O3F3两相;随着焙烧温度的继续升高,(Ce,Pr)La2O3F3可分解为LaF3、Ce2O3、PrO1.83等相。焙烧过程中Ce3+、Pr3+氧化为四价,没有明显的脱氟行为。 相似文献
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《中国稀土学报(英文版)》2020,38(10):1114-1118
Rare earths (REs) and Co are critical strategic resources.Their recovery is crucial for ensuring that their supplies are adequate and for reducing environmental pollution.End-of-life NdFeB magnets are important secondary RE sources.The separation of Dy,Nd,and Co from NdFeB leachate using a relatively new extractant (2,3-dimethylbutyl)(2,4,4'-trimethylpentyl)phosphinic acid (INET-3),was investigated in this study.The separation parameters,such as equilibrium pH,phase ratio,INET-3 concentration,and number of counter-current extraction stages,were optimised.The results show that INET-3 can separate Dy,Nd,and Co efficiently.For the preferential extraction of Dy from synthetic iron-free NdFeB leachate,the optimum equilibrium pH is 2.60.Under this condition,separation of Dy from the leachate requires four counter-current extraction stages at A/O (volume ratio of aqueous to organic)=1:2.This is demonstrated by a simulated four-stage counter-current extraction process.At equilibrium pH=2.52and A/O=1:2,98%of Dy is recovered with 95%purity.As to the subsequent separation of Nd from the leachate,nearly 100%is recovered with 99%purity through a simulated three-stage counter-current extraction process at equilibrium pH=5.33 and A/O=1:1.Approximately 95%of Co remains in the raffinate with 99.98%purity. 相似文献
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从NdFeB磁性材料制造工业废料中提炼金属钕 总被引:2,自引:0,他引:2
综述了从NdFeB生产的工业废料中提炼金属钕的生产工艺及生产工艺条件对产品质量、技术经济指标的影响。应用该工艺得到的金属钕成分特殊,重新用于NdFeB合金熔炼,效益显著;从废料中提炼的具有特殊成分的氧化钕,用3000A电解槽生产,台日产金属钕60kg,电流效率在于75%,金属总收率大于88%,生产工艺先进,成熟、稳定。 相似文献
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Ultrafine NdFeB waste is a relatively clean waste produced during NdFeB magnet processing. Fluorine-containing wastewater is a common type of industrial wastewater, such as stainless steel pickling wastewater. In this work, rare earth element neodynium was recycled from ultrafine NdFeB waste by capturing fluorine ions in the fluorine-containing wastewater and prepared into neodynium oxyfluoride. The reaction process was investigated through UV-Vis-NIR, thermogravimetry/differential thermogravimetry (TG/DTG), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The neodymium hydroxide in the ultrafine NdFeB waste reacted with fluorine ions to form Nd(OH)2F, and Nd(OH)2F was then transformed into neodymium oxyfluoride after decomposition. The formed neodymium oxyfluoride is found to be particles with rhombohedral structure and a particle size of around 50 nm. The reaction kinetics of forming Nd(OH)2F was investigated. The reaction kinetic equation was established and the reaction activation energy was calculated. The effect of fluorine ion concentration on the reaction rate and products was evaluated. The results show that the reaction rate increases with the increase of fluorine ion concentration in the range of 0.01–1.5 mol/L, but it has little effect. In addition, the fluorine ion concentration affects the crystallinity of formed neodymium oxyfluoride. The recycling process not only realizes the sustainable utilization of rare earths, but also reduces the concentration of fluorine ions in the fluorine-containing wastewater, achieving two goals with one stone. 相似文献
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Yinju Jiang Yongchun Deng Wenbin Xin Chao Guo 《Transactions of the Indian Institute of Metals》2020,73(3):703-711
To recover rare earths (RE) with low acid consumption and low environmental pollution, selective pressure leaching with hydrochloric acid from roasted NdFeB scrap was explored. The phase evolution of NdFeB scrap during roasting at 800 °C as a function of time was confirmed, and after complete oxidation, its phase components consisted of Fe2O3, NdFeO3, and NdBO3. In the selective pressure leaching procedure, the optimal leaching was achieved at 110 °C for 30 min, in which the leaching rate of rare earth was 96.27% along with 13.33% of Fe. Subsequently, the effects of the hydrochloric acid dosage, the hydrochloric acid concentration and the particle size of the roasted NdFeB powder on the leaching rate of rare earth were investigated. For leaching at 110 °C for 30 min, the leaching of 13.33% Fe2O3 was derived from the Fe2O3 and NdFeO3 phases in the fully oxidized NdFeB scrap. This phenomenon was verified by the leaching of Fe from Fe2O3 of analytical purity and synthetic NdFeO3. Moreover, the leaching of Nd and Fe from the NdFeO3 phase was found to occur simultaneously. The advantages of the selective pressure leaching process using hydrochloric acid for the oxidized NdFeB scrap were comprehensively evaluated. 相似文献
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钕铁硼磁体中稀土元素钕占据较大比重,从钕铁硼废料回收稀土有重大意义。为进一步了解钕在高温下氟化物熔盐的行为,本文在1 063 K采用NaF-KF(摩尔比2:3)电解质体系,加入质量分数为1%的NdF3,以Pt为参比电极,钨棒为对电极,用循环伏安法等电化学暂态测试研究了Nd(III)在惰性钨电极上的电化学过程,探究Nd(III)的还原机理。结果显示:Nd(III)于NaF-KF-NdF3熔盐中在惰性钨电极上的电化学还原过程是受扩散控制的不可逆的一步反应:Nd(III)+3e-=Nd,1 063 K时循环伏安法得到Nd(III)的扩散系数为2.107×10-5 cm2/s,钕的成核机制为瞬时成核。 相似文献
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Study on Key Techniques for Producing High Performance NdFeB Sintered Permanent Magnets 总被引:2,自引:0,他引:2
NdFeBmagnetshavebeenimproveddra maticallysinceitwasinventedin 1 983 .Twotypesofsinteredmagnets ,highenergyprod ucts ((BH ) max)anddoublehigh (high(BH ) maxandhighcoercivity (iHc) )arethetwotendenciesforNdFeBsinteredmagnets .Bothfactoriesandresearchinstitutesarefocus… 相似文献
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Lü Yousheng 《中国稀土学报(英文版)》2007,25(Z1):125-129
A new alloy of Nd33.5Dy0.99Febal.Al0.52Cu0.1B1.15 (%, mass fraction) was fabricated by powder metallurgy. The effects of Dy, Al and Cu additions on the microstructure and magnetic properties of sintered NdFeB magnet were investigated. The additions of Dy, Al and Cu are effective to refine grains and improve coercivity. Moreover, suitable amounts of Dy, Al and Cu lead to a demagnetization curve with good rectangularity. It is found that the sintered NdFeB magnet has relatively high magnetic performance of Br=12.17kGs, jHc=13.52kOe and (BH)max=34.71MGOe. The sintered NdFeB sample was examined by magnetic force microscope which revealed the domain structures at the surface. It is revealed that the mean Nd2Fe14B grain size is significantly larger than the average scale of the magnetic contrast. An explanation about this is that most Nd2Fe14B grains in sintered NdFeB alloy are dominated with the muhidomain structures when the magnet is in thermally demagnetization state. 相似文献
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研究了从钕铁硼废料中回收稀土氧化物和氧化钴的工艺流程,试验确定了酸分解,草酸沉淀,除铁等杂质的工艺条件,该工艺能有效地除去铁,钙等杂质,试验得到的氧化钴符合GB6518-86纯氧化钴粉Y1类产品要求,钴直收率在82%以上,所得稀土氧化物,其总含量为97%以上,回收率95%以上,达到了综合回收利用的目的。 相似文献
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The effect of cobalt on the magnetic properties and anisotropy of HDDR anisotropic NdFeB was studied.It is found that Co is helpful for preparing anisotropic NdFeB with high coercivity. The research on the initial microstructure for NdFeB alloy indicates that Co tends to enter the crystal lattice of Nd-rich phase and some of Co atoms also enter the crystal lattice of Nd2Fe14B. The dissolution of Co changes the stability of Nd-rich phase and Nd2Fe14 B in H2 atmosphere and affects the kinetics of HDDR phase transformation. As a result, the NdFeB powder exhibits a high coercive force and a strong anisotropy. 相似文献
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UptonowhighperformanceanisotropicNdFeB typemagnetsaremainlymanufacturedbythepowdermetallurgytechnique[1] .Thefi nalmicrostructureofsinteredNdFeBmagnetsisdeterminedbythepre alloypowderparame tersandsinteringconditions .Thetechnologi calimportanceofNd2 Fe14 Bg… 相似文献