Solvent Extraction Of Metal Chelates Research Articles

The Role of Metal Ion Polymerization in Beer's Law Deviations Using Extractive-Colorimetric Procedures

Abstract In the solvent extraction of metal chelates, the presence of polymerized metal ion in either the aqueous or organic layer, can cause the efficiency of extraction to vary throughout a range of metal ion concentrations. Should an extractive-colorimetric determination be employed, a deviation from Beer's Law can result in addition to other intrinsic causes. In this study, the nature of the deviation solely due to polymerization is demonstrated. The absorbances of the extracted metal complexes in the organic phases which are calculated from the analytically determined metal ion concentrations and molar absorptivities are plotted versus the initial metal ion concentrations for some 2,2′-pyridil-mono-and bis-2− and −2.6 in the plots of log D vs. log [M(II)]org. are found. At initial metal ion concentratiolns greater than 6 × 10−5 M, marked negative deviations from the straight line are observed.

Indirect determination of organic compounds by atomic-absorption spectrophotometry

A review of the published methods for analysis of organic compounds by atomic-absorption spectrophotometry is given. Most of the applications are based on precipitation of metal compounds or solvent extraction of metal chelates or ion-association complexes. Although many of the methods offer great sensitivity, simplicity, and speed of analysis, few have been widely accepted by analysts, but some have proved to be satisfactory in field trials.

Substoichiometric Determination of Pd-II-Traces with Dithizone and Problems of Determination

Pd-traces determination by radioactive isotope dilution analysis based on solvent extraction of metal chelates – Dithizone is a reagent frequently used for the substoichiometric separation of trace amounts of metals. In the case of substoichiometric Pd-extraction there are some problems in the reproducibility of determination, because in solutions of dithizone in organic solvents exist two tautomeric species. At present it is supposed in the literature that only the thiol form of dithizone reacts with the metal ions. Extensive studies of reaction between Pd(II) and dithizone using 130Pd suggest an extraction mechanism with the thione form. From this fact follow the general problems and the peculiarity of Pd-determination.

The salt effect for the solubilities of metal β-diketonates—II: Beryllium benzoylacetonate

In order to confirm extensively a generalized interpretation for the salt effect in solvent extraction of metal chelates, the solubilities of bis(1-phenyl-1,3-butanedionato) Be(II) (Be(bzac) 2) in aqueous solutions of LiCl, NaClO 4, NaNO 3, KBr, NaBr, KCl, NaCl and Na 2SO 4 were determined at 25°C. The salting coefficients of these salts for Be(bzac) 2 were obtained from the above data, and were found to accord with McDevit-Long equation except for LiCl. The salting-in effect of LiCl is discussed from the aspect of the strong hydration of small Li + ion. The salting coefficients for Be(bzac) 2 are compared with those for the corresponding copper chelate (Cu(bzac) 2) and an influence of the stereochemical configurations of the metal chelates on the salt effect is also discussed.

The salt effect for the solubilities of metal β-diketonates—I copper benzoylacetonate

A method for the solubility measurement of metal chelates in aqueous solution was devised and those of bis(1-phenyl-1,3-butanedionato)Cu(II)(Cu(bzac) 2) in water and in the aqueous solutions of LiCl, NaClO 4, NaNO 3 NaBr, KCl, NaCl, NaF, and Na 2SO 4 were determined at 25°C. The salting coefficients of these salts for Cu(bzac) 2 were obtained from the above data, and were found to accord with McDevit-Long theory except for LiCl. On the basis of this result, the salt effect on the distribution process of Cu(bzac) 2 is explained by the above theory which predicts the variation of the activity coefficients. of nonelectrolytes with salts, and a generalized interpretation of the salt effect in the solvent extraction of metal chelates is discussed.

Solvent extraction of metal chelates into water-immiscible acetone

Solvent extraction of metal chelates into water-immiscible acetone

Principles and Applications of Substoichiometric Techniques of Analysis

SUMMARY One of the major difficulties associated with the chemical separation usually required in activation analysis for trace elements has been the need to determine the chemical yield of the separation process. In a separation using the substoichiometric principle, equal amounts of a reagent capable of converting the irradiated element and its isotopic carrier to an easily-separable form are added to the prepared sample and to the standard, but the reagent is sufficient to react with only a part of the element and carrier which is present. By this means the specific activities of the extracts or precipitates are made proportional to the total activities, and the determination of the absolute chemical yield of the separation is rendered unnecessary. Furthermore, the use of a substoichiometric amount of reagent usually increases the selectivity of the separation process. The principle can be applied with equal, or even greater, advantage to radioisotope dilution analysis, and its use has greatly extended the application of tracer methods to the analysis of elements at microgram and submicrogram levels. Of the methods which have been adapted for substoichiometric separations of elements, the most common are the solvent extraction of metal chelates and of ion-association compounds, and the ion-exchange separation of soluble complexonates. Precipitation methods have also been used, and both electrolysis and replacement substoichiometry are likely to increase in importance. Substoichiometric methods have been applied with success to the analysis of many metals at trace level in a variety of materials; methods for the analysis of non-metals are also beginning to be developed. Perhaps substoichiometry will make its greatest impact in the development of isotope dilution analysis, a technique which has been neglected for trace analysis in the past because of the need to determine chemical yields. This development is particularly to be welcomed because it extends radioanalytical methods to laboratories which do not have easy access to nuclear reactors for neutron-irradiation.

Some interesting aspects of the extraction of zinc

Abstract

Solvent extraction of metal chelates containing SO<SUB>3</SUB>H group with high molecular weight amines

著者らは高分子量アミンによる酸の抽出を検討してきたが,スルホン基を有する水溶性の有機試薬およびこれと金属イオンとの錯体が上記アミンや第四級アンモニウム塩の存在で低誘電率の有機溶媒に抽出可能であり,生成錯体の分離濃縮ならびに分析感度の向上を期待しうることを知った.これについて二,三の実験例を簡単に報告する.従来,この種の水溶性錯体の抽出はブタノールなどの比較的極性の高い溶媒を用いて二,三行なわれてきたが,以下に示すようなジクロルエタンやトルエンなど極性の低い溶媒への抽出はほとんど行なわれていない.

Book Review: The Solvent Extraction of Metal Chelates. By Jiři Starý. English edition edited by H. Irving

Angewandte Chemie International Edition in EnglishVolume 4, Issue 11 p. 1002-1002 Book Review Book Review: The Solvent Extraction of Metal Chelates. By Jiři Starý. English edition edited by H. Irving Werner Fischer, Werner FischerSearch for more papers by this author Werner Fischer, Werner FischerSearch for more papers by this author First published: November 1965 https://doi.org/10.1002/anie.196510022AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article. Volume4, Issue11November 1965Pages 1002-1002 RelatedInformation

The solvent extraction of metal chelates (Stary, Jiri)

The solvent extraction of metal chelates (Stary, Jiri)

A theoretical approach to the solvent extraction of metal chelates

A simplified theory for the solvent extraction of metal chelates is presented. Factors which are taken into account include the metal ion, the chelating reagent, aqueous complexing agents, adduct-forming substances, the organic solvent, temperature, rates of extraction, and other effects. Equations are developed for estimating the stoichiometries and the association constants of the involved species.

Solvent Extraction of Metal Chelates. III. A Potentiometric Investigation of Alkali-Ion Extraction by Di-(2-hydroxy-1-naphthyl)methane.

Solvent Extraction of Metal Chelates. III. A Potentiometric Investigation of Alkali-Ion Extraction by Di-(2-hydroxy-1-naphthyl)methane.

Solvent Extraction of Metal Chelates. II. An Investigation of some 1-Phenyl-3-methyl-4-acyl-pyrazolones-5.

Solvent Extraction of Metal Chelates. II. An Investigation of some 1-Phenyl-3-methyl-4-acyl-pyrazolones-5.