共查询到20条相似文献,搜索用时 297 毫秒
1.
The extraction behavior of V(IV) in the presence of Mo(VI), W(VI), U(VI), V(V), Ti(IV), Al(III), Cr(III), Fe(III), Mn(II),
Zn(II) and Pb(II) has been studied using two alkylphosphinic acid extractants, Cyanex 272 and 301. The effect of various parameters,
such as the nature of diluent, the type of mineral acid and the concentration of the acid, and metal ions has been investigated.
The loading and recycling capacity of the extractants has been assessed. Based on the distribution data some binary separations
from V(IV) were achieved.
Received: 24 October 1996 / Revised: 2 July 1997 / Accepted: 5 July 1997 相似文献
2.
The extraction behavior of V(IV) in the presence of Mo(VI), W(VI), U(VI), V(V), Ti(IV), Al(III), Cr(III), Fe(III), Mn(II),
Zn(II) and Pb(II) has been studied using two alkylphosphinic acid extractants, Cyanex 272 and 301. The effect of various parameters,
such as the nature of diluent, the type of mineral acid and the concentration of the acid, and metal ions has been investigated.
The loading and recycling capacity of the extractants has been assessed. Based on the distribution data some binary separations
from V(IV) were achieved.
Received: 24 October 1996 / Revised: 2 July 1997 / Accepted: 5 July 1997 相似文献
3.
The mechanism of Re(VII) extraction from sulphate-containing solutions using primary amine Primene JMT, trioctylphosphine
oxide (TOPO), tributyl phosphate (TBP), and their mixtures was investigated. It was found that the ratio of Re(VII) with Primene
JMT and its sulphate in the organic phase was 1:1. The composition of Re(VII) complexes with TOPO depended on the acidity
of solution ranging from about 1:1 to 2:1. When the extraction was carried out by TBP the mole ratio of TBP to Re was approximately
4. Primene JMT proved to be the most suitable agent for Re(VII) extraction with the exception of strongly acidic solutions,
in which TOPO provided better results. The mixed solvents Primene JMT and TOPO as well as Primene JMT and TBP presented a
slight synergism in weakly acidic solutions.
Presented at the 33rd International Conference of the Slovak Society of Chemical Engineering, Tatranské Matliare, 22–26 May
2006. 相似文献
4.
有关协同萃取的研究已十分广泛,但文献报道的大多是有关螯合(或酸性磷)-中性萃取剂组成的协萃体系,关于螯合-螯合萃取剂对金属离子的协萃研究报道甚少。Newman[1],Sekine[2.3]以及Sudersanan等[4-6]曾研究过β-二酮类萃取剂之间的协同萃取,但这类体系的协萃机理和规律性尚有待探讨。本文研究了1-苯基-3-甲基-4-苯甲酰基-5-吡唑啉酮-(PMBP)与噻吩甲酰三氟丙酮(TTA)及PMBP与1-苯基-3-甲基-4-三氟乙酰-5-吡唑啉酮-(PMTFP)两种协萃体系从硝酸介质中对铀(VI)的萃取,这两种协萃体系文献中均未见报道.采用斜率法测求协萃配合物组成,计算了它们的干衡常数,并对协萃反应机理和规律性进行了讨论。 相似文献
5.
6.
Aurocyanide ion-pairs with alkali-metal ions are extracted efficiently into organic phases with the aid of long-chain polyethers. The results of distribution experiments can be rationalized by molecular mechanics calculations. The polyether is shown to co-ordinate to the alkali-metal cation through the ether oxygen atoms, wrapping around the cation in a helical configuration. High extraction efficiencies are obtained with high dielectric-constant solvents, which tend to stabilize the helical polyether-cation complex. The preferential secondary solvation of the aurocyanide anion by the chosen solvents also has an important influence on the extraction efficiency. 相似文献
7.
8.
Oxidation of (η5-C5H5)2MCl (M = Nb, Ta) with 1 mol of Cl2, Br2 or I2 gives (η5-C5H5)2MClX2 whereas the reaction with an excess of the halogen gives the cationic complexes [η5-C5H5)2MClX]+ X3? (X = Br, I). Similar oxidation of (η5-C5H5)2MCl2 with 0.5 mol of halogen gives (η5-C5H5)2MCl2X complexes, but if the halogen is used in excess cationic [η5-C5H5)2MCl2]+ X3? (X = Br, I; M = Ta and X = I, M = Nb) are obtained. All these complexes can also be obtained simultaneously by oxidizing (η5-C5H5)4M2Cl3, and the separation is fairly easy in most cases. Conductivity and IR and NMR data are discussed. 相似文献
9.
10.
11.
G. M. Nair G. R. Mahajan D. R. Prabhu 《Journal of Radioanalytical and Nuclear Chemistry》1996,204(1):103-111
Two isomeric monoamides, dioctyl butyramide (DOBA) and dioctyl isobutyramide (DOIBA) were synthesized for extracting uranium(VI) and plutonium(IV) from aqueous nitric acid medium into various diluents such asn-dodecane, tertiary butyl benzene and xylene. DOBA extracted uranium(VI) and plutonium(IV) efficiently whereas DOIBA extracted uranium(VI) with negligible extraction for plutonium(IV). Both these cations were extracted as their disolvates. The thermodynamic parameters involved in the extraction determined by the temperature variation method indicated the reactions in all cases to be enthalpy favoured and entropy disfavoured. Possibility of separating micrograms of plutonium(IV) from macroquantities of uranium(VI) using the mixture of these amides was explored. 相似文献
12.
报道了含钒(IV)和钒(V)的钨锗混合价杂多酸盐的合成、电子吸收光谱及单电子还原态的ESR谱。α-和β-[HGeV^I^VV2^VW9O40]^7^-的溶液ESR谱是由40余条超精细线组成的, 表明在阴离子中3个VO6八面体是角顶共用, 且其中一个桥氧原子是质子化的。 相似文献
13.
A nonaqueous potentiometric method for the determination of substituted benzophenone oxime reagents (LIX) used as extradants in copper extraction processes is described. t-Butanol is used as the solvent and tetrabutylammonium hydroxide as the titrant. Endpoints are detected with a glass-modified calomel electrode system; a slow rate of titrant delivery is used near the inflection point. The syn and anti isomers of LIX reagents (substituted o-hydroxybenzophenone oximes) can be differentiated. 相似文献
14.
报道了含钒(IV)和钒(V)的钨锗混合价杂多酸盐的合成、电子吸收光谱及单电子还原态的ESR谱。α-和β-[HGeV^I^VV2^VW9O40]^7^-的溶液ESR谱是由40余条超精细线组成的, 表明在阴离子中3个VO6八面体是角顶共用, 且其中一个桥氧原子是质子化的。 相似文献
15.
16.
17.
A. A. Udovenko R. L. Davidovich V. B. Logvinova V. V. Tkachev 《Journal of Structural Chemistry》2016,57(8):1584-1587
Crystal structures of newly synthesized tetramethylammonium hexafluoridoniobate(V) and hexafluoridotantalate(V) (CH3)4N[МF6] (M=Nb, Ta) have been determined; they crystallize in the tetragonal crystal system, sp. gr. P4/nmm. Crystal structures of isostructural compounds (CH3)4N[МF6] (M=Nb, Ta) are formed by virtually regular tetrahedral tetramethylammonium cations (CH3)4N+ (NMe4, TMA) and octahedral complex anions [МF6]– (M=Nb, Ta), fluorine atoms of the equatorial plane are statistically disordered over two positions. Ionic interactions and weak hydrogen bonds C–H???F join the cations and the complex anions in a 3D assembly. 相似文献
18.
Cherkasov R. A. Garifzyanov A. R. Leont’eva S. V. Davletshin R. R. Koshkin S. A. 《Russian Journal of General Chemistry》2010,80(1):151-152
Russian Journal of General Chemistry - 相似文献
19.
B. V. Reddy L. K. Reddy A. S. Reddy M. L. P. Reddy S. Sujatha T. R. Ramamohan A. D. Damodaran 《Journal of Radioanalytical and Nuclear Chemistry》1994,178(1):109-120
Synergistic solvent extraction of Eu(III) and Tb(III) from thiocyanate solutions with mixtures of 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester (EHPNA) and di-2-ethylhexylphosphoric acid (DEHPA) or tributyl phosphate (TBP) or trioctylphosphine oxide (TOPO) or triphenylphosphine oxide (TPhPO) in benzene has been studied. The mechanism of extraction can be explained by a simple chemically based model presented in this paper. The equilibrium constants of the mixed-ligand species of the various neutral donors have been determined by non-linear regression analysis. 相似文献
20.
The crystal structure of tetrachlorophosphorus(V) hexachlorouranate(V), PCl+4.UCl?6, has been solved with 2492 independent F(hkl) collected by necessity from one component of a bicrystal; all crystals prepared were twinned. The structure is triclinic, space group P, with a = 7.038(4), b = 7.373(4), c = 13.706(8) Å, α = 89.38(3), β = 88.80(3), γ = 105.20(3)°, with Z = 2. The two components of the bicrystal, in the volume ratio of 2.5 to 1, had their reciprocal lattice spots sufficiently separated to allow collection of the data set from component 1 with AgKα radiation (λ = 0.5608 Å). A model was derived from the Patterson synthesis and refined by least squares to R = Σ(|Fo|-|FC|)/Σ|Fo| = 0.146. The structure was confirmed by a final (ρo-ρc) synthesis. The structure is an assembly of octahedral U(1)Cl?6, U(2)Cl?6 and tetrahedral PCl+4 groups. The chlorine atom array is hexagonal close-packed, while the polyhedra are regular within the experimental errors. The structure is isomorphous with the transition metal analogues PCl5.NbCl5 and PCl5.TaCl5. 相似文献