Separation of Scandium and Rare Earths with the Method of PSO-Extraction Chromatography

Separation of scandium and rare earths was investigated by using a new extraction chromatography whichPSO was used as a stationary phase,while HCl-NH_4SCN solution as a mobile phase.The separation conditionswere studied.In this system, the separation factor(β_(Nd)~(Sc))can reach up to 1.3×10~4.The method can be applied tothe purposes of separation,purification and analysis of microquantity of Sc in the mixed rare earth.     

Voltammetric Study on the Complexes of the Rare Earths with Tetraphenylporphyrin

Fifteen rare earth-tetraphenylporphyrin(RE-TPP)complexes were directly prepared by mixing equalmolar concentrations of RE(ClO_4)_3 and H_2TPP in acetone media.The electrochemical behaviors of these com-plexes and the influence of dissolved oxygen were investigated by voltammetry.Althrough there are some differ-ence between the behaviors of light and heavy rare earth-porphyrins,the central RE ions of the all fifteen com-plexes were reduced from tervalent to divalent state,meanwhile the dissovled oxygen was reduced as superoxideion O~-.which readily combined with the complex forming peroxide additive complex such as RE-TPP·O~(2-)_2.     

Study of Rare Earths in Pipeline Steel

ＳｔｕｄｙｏｆＲａｒｅＥａｒｔｈｓｉｎＰｉｐｅｌｉｎｅＳｔｅｌＬｉｕＹｏｎｇｈｕａ（刘勇华），ＹｅＷｅｎ（叶文），ＬｉｎＱｉｎ（林勤）ＣｈｅｎＮｉｎｇ（陈宁）（ＤｅｐａｒｔｍｅｎｔｏｆＰｈｙｓｉｃａｌＣｈｅｍｉｓｔｒｙ，ＵｎｉｖｅｒｓｉｔｙｏｆＳｃｉ...     

Linear Free Energy Relationships in Extraction of Rare Earths by Acidic Organophosphorus Extractants

Acidicorganophosphorusextractantsareanimportantclassofrareearthextractants,andtheirextractionbehavioursarecloselycorrelatedwiththeirstructures.Therefore,thestudiesontherelati0nshipsbetweenthestructures0facidicorganophosph0rusextractantsandtheirextractionbehavioursforrareearthareasignificantsub-ject,andmanydatahavealreadybeenaccumu-latedtodate.H0wever,forthem0st0fstudies,onlyqualitativeregularitieshavebeenobtained.Forthedesignofhighlyeffectivenewextrac-tant8,fuFtherstudiesonquantitativerelati0n…     

Structure Reactivity Studies on the Extraction of Rare Earths by Di(2-ethylhexyl)chloroalkyl Phosphonates

The extractive separation properties and the extractive regularity of the lanthanide elements by fivedi(2-ethylhexyl)alkyl phosphonates with various alkyl structure:di(2-ethylhexyl)chloromethyl phosphonateCH_2ClP(O) (OC_8H_(17)-i)_2(1),di(2-ethylhexyl)β-chloroethyl phosphonate ClCH_2CH_2P(O) (OC_8H_(17)-i)_2(2),di(2-ethylhexyl)α-chloroethyl phosphonate CH_3CHClP(O)(OC_8H_(17)-i)_2 (3),and correspondingdi(2-ethylhexyl)methyl phosphonate CH_3P(O)(OC_8H_(17)-i)_2 (4),di(2-ethylhexyl)ethyl phosphonateC_2H_5P(O) (OC_8H_(17)-i)_2 (5),in nitrate system have been studied.The coordination compounds were prepared.The structure of these extractants and their coordination compounds were further explored by IR and ~(31)P NMRspectra.     

新型大孔膦酸浸渍树脂萃取色层分离重稀土的研究

研究了用浸渍Cyanex272的大孔磷酸树脂萃取色层分离重稀土Tm-Yb,Yb-Lu。结果表明,在淋洗液酸度2．5mol/L,稀土负载量1%,柱高径比30：1,淋洗流速1mL/min时,Yb,Lu分离效果较好;在淋洗液酸度1．8mol/L,稀土负载量0．8%～0．9%,柱高径比30：1,淋洗流速1mL/min时,Tm,Yb的分离效果较好。与使用P507萃淋树脂萃取色层分离相比,淋洗液酸度较低,而且可以减少梯度淋洗,减轻了后处理工序的生产强度,降低生产成本,对工业应用很有价值。     

富集稀土磷酸溶液中稀土的萃取研究

研究了P204从富集稀土磷酸溶液中稀土元素钇、镧、钕的萃取行为,并考察了初始水相中P_2O_5浓度、萃取相比、萃取剂浓度、萃取时间对稀土萃取效果的影响。结果表明,低磷酸浓度、较大相比、较高萃取剂浓度和较长萃取时间有利于萃取稀土,并得到了萃取优化条件:初始水相中P_2O_5浓度10%、萃取相比V_0/V_1=3/1、萃取时间15min、P204浓度30%,在室温下萃取钇、镧、钕3种稀土,单级萃取率均可达到90%以上。     

稀土6063变形铝合金阳极氧化与电解着色的研究

本文系在硫酸、硫酸亚锡溶液中对添加有稀土的6063变形铝合金进行了阳极氧化和电解着色。比较系统地研究了氧化电解液的浓度、温度、时间、电流密度对膜层厚度的影响;以及着色电流密度、电压、时间对膜层色度的影响。结果证实,稀土可以明显地提高6063变形铝合金氧化膜厚度和电解着色的色度,稀土含量以0.30％为好。     

稀土氨基酸配合物的研究情况分析

系统分析了 1991～ 2 0 0 1年间发表的近百篇有关稀土与氨基酸配合物的文献 ,主要讨论作者国籍、刊物、机构、内容和方向等方面的问题。中国的科研人员对稀土氨基酸二元配合物的合成、性质、结构进行了系统的研究。从 90年代末开始 ,研究朝着稀土 氨基酸 过渡金属异核配合物和以氨基酸为配体的高pH值下镧系 羟基自组装配合物的方向发展     

Influence of Rare Earths on the Directional Solidification Microstructure of Tin-Lead Eutectic Alloy

ＩｎｆｌｕｅｎｃｅｏｆＲａｒｅＥａｒｔｈｓｏｎｔｈｅＤｉｒｅｃｔｉｏｎａｌＳｏｌｉｄｉｆｉｃａｔｉｏｎＭｉｃｒｏｓｔｒｕｃｔｕｒｅｏｆＴｉｎＬｅａｄＥｕｔｅｃｔｉｃＡｌｏｙＺｈｕＹｉｎｇ（朱颖），ＦａｎｇＨｏｎｇｙｕａｎ（方洪渊），ＱｉａｎＹｉｙｕ...     

Effect of Rare Earths on the Quality of Brush-plated Coating

ＥｆｅｃｔｏｆＲａｒｅＥａｒｔｈｓｏｎｔｈｅＱｕａｌｉｔｙｏｆＢｒｕｓｈｐｌａｔｅｄＣｏａｔｉｎｇＬｉＭｕｑｉｎ（李慕勤），ＭａＣｈｅｎ（马臣）（ＪｉａｍｕｓｉＩｎｓｔｉｔｕｔｅｏｆＴｅｃｈｎｏｌｏｇｙ，Ｊｉａｍｕｓｉ１５４００７，Ｃｈｉｎａ）Ｌｉ...     

Combination of on-line preconcentration by di(2-ethylhexyl) phosphoric acid resin in the presence of complexing agent with microwave plasma-atomic emission spectrometry for the determination of rare earths

The adsorption of rare earths,lanthanum,cerium,neodymium,and yttri um by di(2-ethylhexyl) phosphoric acid(D2EHPA) resin in the presence of a compl exing agent,EDTA,was investigated. Flow injection was selected as the injectin g method. Various parameters,sample pH,sample loading time,sample flow rate,EDTA concentration,EDTA flow rate,eluent concentration,and eluent flow rate,were studied and optimized. Under the optimum conditions,the method allowed the determination of rare earths with detection limits of 1.09 μg/L(lanthanum),3 .31 μg/L(cerium),2.05 μg/L(neodymium),and 1.25 μg/L(yttrium) . High repea tabilities were obtained for all the four rare earths(RSD<5%) . The proposed met hod was applied to the determination of the rare earths in water samples with a recovery range of 95.8%-103.3%.     

Effect of the Rare Earths on the High Temperature Properties of Deformed Leaded-Brasses

The effect of the rare earths on the high temperature properties of deformed leaded-brasses has been stu-died with the high temperature tensile test.The results show that the rare earth additives can increase elongationof alloys at high temperature,but they had little effect on the maximum flow stress.With the help of SEM.X-ray diffraction instrument,quantitative metallography analysis instrument,etc.,the effect of the rare earthelements on the mierostrueture of alloys has also been examined.     

Study of Transport and Separation of Rare Earth Ions through the Emulsion Liquid Membrane of Bis(2,4,4-trimethylpentyl)phosphinic Acid-Span 80-Toluene

It is indicated from a study of transport of rare earth ions through the emulsion liquid mem-brane of bis(2,4,4-trimethylpentyl)phosphinic acid-Span 80-toluene that transporting rare earth ions com-pletely and rapidly was realized under the optimum experimental conditions:1.0×10~(-3)～3.0×10~(-3)mol/Lbis(2,4,4-trimethylpentyl)phosphinic acid and 2%～4%(W/V)Span 80 in toluene solution as membranephase,0.50～2.0 mol/L HCl as inner phase,rare earth ion solutions with pH 3.5～5.0 as outer phase.Ac-cording to the differences of transport behavior for rare earth ions,it is possible to separate rare earth ionsfrom mixed solutions of rare earth ions by this liquid membrane system.     

镧镨铈(LPC)稀土在6063铝合金中的作用

论述了镧镨铈(LPC)新型混合稀土铝中间合金作添加剂，其在6063铝舍金中起净化，使铝合金晶粒细化，同时又能改善铝合金的耐腐蚀性能的作用和效果。     

A comparative investigation into floatability of bastnaesite with three di/trialkyl phosphate surfactants

Flotation separation and recovery of rare earth minerals (REM) have returned to an important position due to the growing strategy demand for rare earth elements (REE). In this paper, a comparative investigation into the floatability of bastnaesite ((Ce,La)FCO₃) was conducted by using three di/trialkyl phosphate collectors, di(2-ethylhexyl) phosphate (DEHPA), dibutyl phosphate (DBP) and tributyl phosphate (TBP). The density functional theory (DFT) computation recommends that the chemical activity of the three phosphate collectors is in order of DEHPA ≥ DBP >> TBP, and their hydrophobization as-suggested by the lgP (oil-water partition coefficient) value is in the order of DEHPA > TBP > DBP. The micro-flotation indicates that the preferable pH values for flotation of bastnaesite with the three phosphate collectors are 7.0–8.0, and DEHPA achieves much higher flotation recovery of bastnaesite, followed by DBP, and then TBP, which coincides with their reactivity and hydrophobicity, the two prerequisites for froth flotation. The contact angle, zeta potential, Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) deduce that DEHPA likely reacts with the Ce(Ⅲ) atoms of bastnaesite interface through its O atom(s) of the P(=O)–O^– group to generate the Ce–O–P bonds, and its two 2-ethylhexyl groups orient outside for attaching bubbles, resulting in flotation enrichment of bastnaesite. Furthermore, this investigation offers a novel strategy for developing collectors in selective beneficiation of REM.     

三烷基氧化膦萃取稀土元素的研究

研究了国产三烷基氧化膦(混合)对稀土元素La～Gd及Y硝酸盐的萃取.试验了30%三烷基氧化膦(TRPO)-煤油-硝酸体系中水相酸度0.5mol/L～7mol/L范围内轻稀土元素的分配比和相邻两稀土元素的分离因子,测定了TRPO稀土萃合物的组成,探讨了γ射线辐照对稀土元素萃取性能的影响.     

萃取色层梯度淋洗法分离钆铽镝的研究

本文研究了Ｐ５０７－ＨＣｌ体系萃取色层法分离钆铽镝的影响因素，在温度为５０℃、流速０．７５ｍｌ·ｃｍ（－２）·ｍｉｎ（－１）和负载量１６４．２ｍｇ的条件下，用０．４２、０．５２和０．７８ｍｏｌ·Ｌ（－１）ＨＣｌ溶液梯度淋洗，可分别将Ｇｄ、Ｔｂ和Ｄｙ彻底分离。     

稀土元素火焰原子吸收光谱法中有机试剂作用的研究进展

在稀土元素火焰原子吸收光谱法中,有机试剂能提高其灵敏度和选择性,颇有价值。本文综述了该领域的研究进展。     

用叔胺萃取铀分离钍及稀土的研究

对独居石苛性钠浸出，盐酸优溶产生的优溶渣的硫酸浸出液，用叔胺Ｎ２３５萃取铀分离钍及稀土进行了研究。结果表明：铀的萃取率大于９９．５％，反铀液中ＴｈＯ＿２／Ｕ为（１．８～３．８）×１０￣（－３），ＲＥ＿ｘＯ＿ｙ／Ｕ为（１．０～１．６）１０￣（－３），萃铀余液中的Ｕ／ＴｈＯ＿２仅为（３．５～５．６）×１０￣（－５）。