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1.
根据精馏理论及单2-乙基己基膦酸2-乙基己基酯(P-507)萃取稀土的机理和性能,提出了用P-507逆流液液回流萃取富集镥的流程。通过模拟试验,设计了在混合澄清器中由十一级萃取转相、二十级贫化、六十级富集、三十级硝酸反萃转相、七级盐酸反萃和二级水洗的流程,经过较长时间的运转,表明本流程可以由混合重稀土(Tm<1%、Yb~89%、Lu~8%、Y~3%)中获得纯度大于99.95%和收率大于98%的镥,并在贫化段中可以定量回收纯度>92%(Lu<0.4%)的镱。稀土总收率为98%,与传统的萃取-汞齐-离子交换法相比较,本法具有产率高、成本低、工艺简单和无汞害的优点。  相似文献   

2.
Cyanex272-P507浸渍树脂协同萃取色层分离铥镱镥的研究   总被引:1,自引:0,他引:1  
以Cyanex272-P507浸渍树脂采用萃取色层法对铥镱镥富集物进行了吸附和淋洗分离研究,考察了淋洗剂浓度、稀土负载量、淋洗液流速等因素对分离铥镱镥富集物的影响。结果表明,在充填的树脂粒度为0.3~0.6 mm的色层柱中,以0.2 ml.cm-2.min-1进料流速时能得到较大的吸附率;在稀土负载量为树脂重量的0.6%,淋洗液流速为1.0 ml.cm-2.min-1,温度为30℃,装柱树脂高度为400 mm(高径比为25∶1)的条件下,用1.0,1.5,2.0 mol.L-1盐酸梯度淋洗Tm,Yb,Lu,可实现铥镱镥富集物三者的完全分离。  相似文献   

3.
2-乙基已基磷酸-2-乙基己基酯(P507)已广泛用于萃取分离稀土元素,用于萃取镓、铟、铊,在盐酸或硫酸介质中均具有较好萃取性质,易于反萃取。鉴于分析分离中萃取色谱法较萃取分离更为实用,我们进一步研究了萃取色谱分离镓、铟及其伴生元素的方  相似文献   

4.
本工作是配合P_(507)萃敢剂简写HA_2)分离镥的性能测试而建立的。实际萃取分离对象是镱、镥富集物的硝酸或盐酸溶液。其中,镱的含量较高,串级分离后镥的含量逐渐升高,因此分析范围(以某稀土在总稀土中的含量——克分子百分率表示)定为镱和镥均在90%以上,铥和钇分别为10%及20%以下。对镥分量为90%以上的试样,则作镱-镥二元分析。以上四元及二元Re(NO_3)_3的总浓度约为0.03M(相当氧化物约为6毫克/毫升)。同时也采用本法,对水相及有机相中低浓度镥进行了测定,它们的最低点浓度相当的氧化镥分别约为0.008和0.005毫克/毫升。稀土元素的X射线荧光光谱分析报导很多,根据不同的分析对象,试样形式也不同。有  相似文献   

5.
刘川楹  陈继  邓岳锋 《应用化学》2018,35(12):1492-1496
稀土元素钪(Sc)在相关原料中含量低,伴生杂质元素多,回收困难。针对这一问题,本文系统对比了直链三烷基氧化膦(Cyanex 923)、2-乙基己基磷酸单-2-乙基己基酯(P507)、环烷酸在硫酸体系中对Sc的萃取、分离和反萃。Cyanex 923在高酸度下能完全萃取Sc,而环烷酸和P507则在低酸度下有较高萃取率。Cyanex 923分离Sc与锆(Zr)、钛(Ti)的最佳水相酸度为1 mol/L,分离系数分别为5. 6和10. 6。P507在水相H~+浓度为2 mol/L时对Sc/Zr、Sc/Ti有最大分离系数,分别是21和59. 7。虽然P507有更好的分离效果,但难以反萃。3种萃取剂中仅有Cyanex 923能被有效反萃,在反酸H+浓度为0. 4 mol/L时有最大反萃率。因此,Cyanex 923更适合从含Sc二次资源浸出液中分离回收Sc。  相似文献   

6.
在萃取色层法分离稀土元素中,常用的固定相有:二(2-乙基已基)磷酸(P-204)、2-乙基已基苯基磷酸、2-乙基己基磷酸单2-乙基己基酯(P-507)等。二(1-甲基庚基)磷酸(P215)是P204的异构体,它的支链在α位置上,空间位阻较大,因此对稀土元素的分离应具有较高的分离因数,反萃取的酸度也应比P204的低。我们将P215用于萃取色层法以分离稀土。在一定的酸度下,可将14个稀土元素分离,在有硫酸铵存在时,也可将Y与Ho和Er分离。  相似文献   

7.
应用响应曲面法研究盐酸体系中P507萃取稀土元素的分配比与初始酸度、稀土初始浓度的关系及在盐酸、硝酸体系中P507对Dy~(3+)的萃取情况。结果表明,在盐酸介质中,体系中Dy~(3+)的初始浓度和初始酸度均较低时,有利于P507对Dy~(3+)的萃取,且硝酸体系优于盐酸体系。  相似文献   

8.
本文论述了2-乙基己基膦酸单2-乙基已基酯(P507)、1-苯基3-甲基4-苯甲酰基吡唑啉酮-5(PMBP)与三辛胺(TOA)的甲苯溶液,从盐酸底液中萃取铕和铽的机理。该体系属于螯合、离子缔合AAC类,并根据实验数据得到了该体系的一元、二元和三元萃取平衡常数。  相似文献   

9.
沈璐  陈继  邓岳锋 《应用化学》2016,33(3):330-335
利用双功能离子液体萃取剂三辛基甲基氯化铵2-乙基己基磷酸2-乙基己基酯盐([A336][P507])在HCl和HNO3介质中对Sc(Ⅲ)的萃取和分离。研究表明,萃取剂在低酸度条件下,对Sc(Ⅲ)有较好的萃取能力;但是当水相酸度从0.5 mol/L增加到4 mol/L,Sc(Ⅲ)的萃取率有较大程度的下降。并且讨论了在HCl介质和HNO3介质中,[A336][P507]萃取Sc(Ⅲ)的机理,由于Sc(Ⅲ)的半径最小,而且在萃取过程中存在PO与P—O的竞争作用,使得其萃合物结构与轻稀土不同。水相中加入盐析剂Na Cl或Na NO3对Sc(Ⅲ)的萃取有一定的促进作用;萃取过程的热力学参数的结果表明,萃取反应是放热反应。还研究了混合稀土中Sc(Ⅲ)和其它稀土离子的分离,在较低酸度的条件下萃取剂[A336][P507]对其它稀土离子的萃取可以忽略不计,因此该萃取体系对Sc(Ⅲ)和其它稀土离子有较好的分离效果,显示了本研究潜在的应用价值。  相似文献   

10.
研究了用2-乙基己基膦酸单-2-乙基己基酯(HEH/EHP,P507)和二(2-乙基己基)磷酸(HDEHP,P204)从硫酸介质中协同萃取Ce(Ⅳ)的机制.结果表明:在HEH/EHP的摩尔分散在0.6时,体系的协萃系数最大.Ce(Ⅳ)以Ce(SO4)0.5HL2A2的形式被萃人有机相,协萃反应为阳离子交换机制.同时还得到了HEH/EHP和HDEHP从硫酸介质中协同萃取Ce(Ⅳ)时,体系的平衡常数及热力学函数如△G,△H和△S等.  相似文献   

11.
酸法浸出石煤提钒因具有环保、金属收率高的特点而备受关注,但同时进入母液的铁(高含量的Fe3+)严重影响了钒的富集和产品生产。 对此,本文提出一种基于“抑制-萃取”效应的钒/铁分离混合萃取体系(P507(2-乙基己基磷酸-单2-乙基己基酯)+ N235(三辛/癸烷基叔胺)+磺化煤油),并详细研究了各因素对钒铁分离和钒富集的影响规律。 结果表明,P507是钒铁萃取的主体,N235不具萃Fe3+能力,是产生抑制铁萃取的关键因素,其浓度越高铁萃取率越低;对于酸度较高(pH≤0.4)的原料液钒/铁的分离效果仍较好,这表明了该“抑制-萃取”混合萃取体系对高酸度浸出液钒/铁分离的适用性。 采用氨水从负载有机相中反萃取钒铁,当氨水浓度为6 mol/L时钒的反萃率99%以上,25 ℃,V(有机相)∶V(水相)=2∶1时的反萃液中钒质量浓度14.73 g/L,铁质量浓度小于0.022 g/L,m(V)/m(Fe)=669.5。 该“抑制-萃取”法分离钒/铁操作简单、经济高效,极具工业化前景。  相似文献   

12.
Murakami M  Takada T 《Talanta》1991,38(10):1129-1135
The extraction of copper(II) from strongly acidic solution (0.01-8M hydrochloric and 0.01-5M nitric acid) with ammonium 1-pyrrolidinecarbodithioate in di-isobutyl ketone has been studied. Compared with the hydrochloric acid system, a considerably larger amount of the reagent is needed for complete extraction of copper chelate from nitric acid solution as the extract is more unstable in the nitric acid system. The decomposition of copper chelates extracted from nitric acid is based on the oxidation of the reagent and the chelate; the spectral change of the extract from nitric acid suggests that the copper(II) chelate is initially oxidized to copper(II) and then decomposes. The upper limit of the acidity of both acids from which the copper chelate can be quantitatively extracted strongly depends on the reagent concentration; the limit with 8 x 10(-2)M APCD (500-fold reagent: metal molar ratio) was taken as 8 and 4M for hydrochloric and nitric acid, respectively.  相似文献   

13.
A new method is proposed for the extractive Chromatographic separation of antimony. Antimony is extracted from 0.001–0.5M hydrochloric acid by a silica gel column coated with bis (2-ethylhexyl) phosphoric acid stripped with 2–8M hydrochloric, nitric or sulphuric acid, and determined spectrophotometrically at 555 nm as its complex with phenylfluorone. Antimony can thus be separated from a large number of elements, including iron, manganese, copper and thallium. Arsenic, antimony, bismuth and tin can be sequentially separated.  相似文献   

14.
Solvent extraction of thorium was studied using Taguchi method. The effect of various parameters such as acid types (sulfuric, nitric, hydrochloric, sulfuric + nitric) and their concentrations from 0.001 to 4 M, initial thorium concentration (0.0001, 0.001, 0.01, 0.1 M) and solvent type (TBP, D2EHPA, Cyanex921, Cyanex272) in the ranges of 0.001 to 1 M on thorium extraction efficiency were investigated. The maximum extraction of thorium was obtained while 0.001 M hydrochloric acid, 0.001 or 0.01 M thorium and Cyanex272 were used. Under these optimum conditions, the extraction percent and distribution coefficient of thorium were 98.7% and 73.8, respectively. Compared with the hydrochloric aqueous solution, the nitric acid system showed less variation in the extraction of thorium. The proposed process has been applied for the separation of Th(IV), U(VI), La(III), and Ce(III) from synthetic solution same as thorium ores (monazite).  相似文献   

15.
The142/140Ce unit separation factor (q) for Ce(III)-Ce(IV) exchange reaction in an extraction system containing Ce(IV) in tri-n-butyl phosphate (TBP) and Ce(III) in hydrochloric acid has been determined. The value of q was found to be 0.9996±0.0001 (2) in the 12M HCl/TBP extraction system. The properties of the extraction systems containing nitric and hydrochloric acids in regard to isotope partition have been discussed.  相似文献   

16.
A new reagent (2-ethylhexyl-3-pentadecylphenyl) phosphoric acid (EPPA = HR) was synthesized from cardanol (I, 37300-39-5) and was used to investigate the extraction behaviour of lanthanum(III), europium(III) and lutetium(III) from hydrochloric acid solutions. The species extracted were found to be Ln(HR(2))(3) (where Ln = La(III) or Eu(III) or Lu(III)). The extraction behaviour of the above lanthanides has also been compared with yttrium and other rare earths. It was observed that the extraction increases with increase in atomic number of rare earths. In addition, the extraction efficiency of EPPA has also been compared with well known acidic organophosphorus extractants like di-2-ethylhexyl phosphoric acid (DEHPA), 2-ethylhexyl-mono-2-ethylhexyl phosphoric acid (EHEHPA).  相似文献   

17.
刘建  王秀山 《应用化学》1990,7(4):37-41
本文考察了萃淋树脂CL-P507对钨、钼的吸附性能,测定了树脂的饱和吸附容量,得出了在H_2SO_4-EDTA体系中从含大量钨的溶液中分离钼的条件。  相似文献   

18.
The solvent extraction method involving diglycolic acid (dicarboxy methyl ether) as a competitive ligand to lutetium and N-tris[hydroxymethyl]methyl-2-aminoethanesulfonic acid (TES) as a buffer was used to study the hydrolysis of lutetium in 1 mol⋅dm−3 NaCl ionic strength at 303 K. Acid dissociation constants of H2DG and TES were determined and the possible formation of lutetium–TES compounds was investigated. It was found that lutetium does not form compounds with TES under the experimental conditions. The solvent extraction method using 177Lu as a tracer was applied and the first hydrolysis constant of lutetium was determined by means of the relationship of the equilibrium constant of the complex Lu(DG)+ in the absence and in the presence of hydrolysis. The value obtained was log 10 β Lu,H=−7.9±0.3.  相似文献   

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