ISSN:0736-6299    

DOI:10.1080/07366299308918151

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

The non-ideality of multicomponent media are difficult to describe, especially for situations as complex as the extraction of metals into organic media

ISSN:0736-6299    

DOI:10.1080/07366299308918152

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

The extraction of nitric acid from aqueous solutions ranging from 0·2 to 8 M nitric acid has been investigated using the novel extractant, N,N-N’,N’-octabutylimidodiphosphotetramide which is at present under study as a possible trivalent f-element extractant. Thermodynamic modelling using non-linear least squares fitting of distribution data found that three complexes were formed in organic phases consisting of various concentrations of the extractant in CCl4. These were (E·HNO4), (2E·HNO3) and ((E·2HNO3). Extraction equilibrium constants were calculated for all three complexes and found to vary with initial extractant concentration.

ISSN:0736-6299    

DOI:10.1080/07366299308918153

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

Removal of organic compounds from hydrocloric acid can be performed by a solvent extraction process followed by a solvent regeneration step by adsorption with sepiolite. The extraction study includes the analysis of the influence of the operating conditions, the determination of the solute distribution coefficient for isooctane and the effect of temperature on the extraction. The adsorption isotherms were calculated to check the technical viability of the method. The obtained efficiency of extraction is close to 90 wt%, whereas that of the solvent regeneration recovery is over 67 wt%

ISSN:0736-6299    

DOI:10.1080/07366299308918154

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

Screening published data about Ti(IV) extraction shows a double-maximum dependence on acidity for most extractants. Various effects of acidity on the aqueous and the organic phases and on extraction mechanism, were employed. A good correlation was found between the nature of the dominating species in the aqueous phase and the ranges of efficiency of the various families of extractants.

ISSN:0736-6299    

DOI:10.1080/07366299308918155

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

Solvent extraction of titanium(IV) from hydrochloric acid solutions by mixtures of mono- and di-2-ethylhexyl phosphoric acid esters (MEHPA and DEHPA) has been investigated as a function of HC1 concentration in the aqueous phase and extractants concentration in the organic phase

ISSN:0736-6299    

DOI:10.1080/07366299308918156

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

In this paper we describe the solvent extraction behaviour of three calixarene-type cyclophanes towards trivalent lanthanides Ln3+(Ln = La, Nd, Eu, Er and Yb). By using p-tert-butylcalix/6/arene hexacarboxylic acid (LI), the lanthanides were extracted from the aqueous phase at pH 2 to 3.5 into chloroform according to a cation exchange mechanism as 1:2 metal:ligand complexes. The extractability is: Nd, Eu > La > Er > Yb. In the presence of excess Na+in the aqueous phase, this order was not changed but the lanthanides were extracted as 1 : 1 complexes at low extractant concentration and their extractability decreased.

ISSN:0736-6299    

DOI:10.1080/07366299308918157

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

The synergistic action of tributyl phosphate in the extraction of La(III), Pr(III)Nd(III), Sm(III), Eu(III), Gd(III), Dy(III), Ho(III), Er(III)and Y(III) with trioc-tylmethylammonium nitrate was studied. The synergistic effect is diluent dependent. It is pronounced with a mixed dodecane/xylene diluent, and is weak with mixed heptane/xylene and hexane/xylene diluents as well as with pure xylene diluent. Two or three synergistic complexes are formed simultaneously in the organic phase. Their composition is (A+)(Ln(N03))4),.2B~), (A+))(Ln(N03))J.3B"), and (A+))2) (Ln(N03))5).BJ-) (Ln is a lanthanide(IM), A+ is a trioc-tylmethylammonium cation and B is a tributyl phosphate molecule). The stability of the synergistic complexes generally decreases with increasing atomic number of the lanthanides(III). The synergism enhaces the efficiency of the lanthanide(III) extraction with trioctylmethylammonium nitrate, but deteriorates its selectivity. The separation factors for the Pr(III)-Nd(III) and Eu(III)-Gd(III) pairs are gradually suppressed at increasing concentration of tributyl phosphate.

ISSN:0736-6299    

DOI:10.1080/07366299308918158

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

Extensive characterization (IR, UV, H1-NMR and GC-MS) of new, non commercially available 7-substituted-8-hydroxyquinoline derivatives labeled TN 1911, TN 2181, TN 2221 and TN 2336, manufactured by Schering Berlin AG., (Germay) is reported here. GC-MS allowed for the identification of isomers present in TN 1911 and Lix 26 (Henkel) extractants. Purity, molecular weight and molarity of the active substa“as received” extractants, are also reported. Finally, hydrochloric acid and the accompanied water extraction performance of Kelex 100, TN 1911 and Lix 26 as well as the occurrence of protonated extractant in the organic phase is also discussed.

ISSN:0736-6299    

DOI:10.1080/07366299308918159

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

The temperature effect on the solvent extraction of Np(V) byn-octyl(phenyl)-N,N-diisobutylcarbamoylmethylphosphine oxide (CMPO) from nitric acid solutions was studied. A slight decline of distribution ratio was observed at increasing temperature in the CMPO and CMPO-TBP systems, It was found that HNO3is extracted by CMPO with the following extraction stoichiometry:

ISSN:0736-6299    

DOI:10.1080/07366299308918160

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor