Extraction Of Alkali Metal Cations Research Articles

Catalytic ability of a flexible octopus-type calix[6]arene in ester-forming reactions and its structural properties

The ester-forming reaction of alkali metal carboxylates with alkyl halides was catalyzed by the octopus-type calix[6]arene 1 which bears six 3,6,9-trioxadecyl substituents at the phenolic oxygens. The catalytic ability of 1 was significantly large in CH 2 Cl 2 and CH 3 CN but negligible in less polar solvents such as benzene and dioxane. The catalytic ability is also affected by the amount of water present in the reaction system. A similar solvent effect was found in the alkali metal cation extraction by 1 from aqueous solutions to organic solvents. The conformation and structural mobility of 1 in organic solvents were studied by 1 H NMR spectroscopy at varying temperatures. Compound 1 had a 1,4-anti conformation both in CD 2 Cl 2 and C 6 D 6 , but the orientation of the substituents on the aromatic rings of 1 varied with temperature. The reactivity features of 1 are discussed on the basis of its structural properties

FIA Potentiometric and Solvent Extraction Studies of Alkali Metal and Alkaline Earth Cation Complexation bybis(Tert-butylbenzo)-21-crown-7

Abstract A flow injection analysis study of the potentiometric selectivity of bis[4(5)-tert-butylbenzo]-21-crown-7 (D(tBB)21C7) for cesium over the other alkali metal cations and three alkaline earth cations has been conducted. A PVC matrix membrane containing D(tBB)21C7 as an ionophore was coated on the tip of a silver wire incorporated in a flow cell. No selectivity for cesium over rubidium and only low selectivity over potassium were noted. However, very high selectivities for cesium over sodium, lithium, strontium, calcium, and magnesium were observed. Selectivity of D(tBB)21C7 in the solvent extraction of alkali metal cations was determined by the picrate extraction method. The percent extraction into deuteriochloroform decreased in the order cesium, rubidium > potassium » sodium » lithium. Thus good agreement was observed between the responses of D(tBB)21C7 towards alkali metal cations in polymeric membrane electrodes and in solvent extraction.

Metal ion separations with proton-ionizable crown ethers and their polymers

Abstract Lipophilic crown ethers with pendent proton-ionizable groups are novel complexing agents for use in metal ion separations by solvent extraction. For a series of structurally related, lipophilic dibenzocrown ether carboxylic acids, the efficiency and selectivity of competitive alkali metal cation extraction for aqueous solution into chloroform is found to be strongly influenced by the crown ether ring size and the lipophilic group attachment site. Reaction of dibenzocrown ether carboxylic acids with formaldehyde in formic acid produces condensation polymers which possess both ion-exchange and cyclic polyether binding sites for metal ion complexation. These resins exhibit excellent exchange kinetics for competitive alkali metal cation sorption from aqueous solution and subsequent stripping and may be used in concentrator columns for the recovery of these metal ions from very dilute aqueous solution. Cation selectivity in the sorption and stripping steps is controlled by the structure of the crown e...

Anion effect on selectivity in crown ether extraction of alkali metal cations

For the solvent extraction of metal ions and their transport across liquid membranes by neutral ionophores, concomitant transfer of one or more aqueous-phase anions into the organic medium is required for electroneutrality. The efficiencies of metal ion extraction and liquid membrane transport flux exhibit a pronounced inverse dependence on the solvation energy of the accompanying anion. Scattered literature reports suggest that the selectivity of metal ion extraction and transport by neutral synthetic and natural ionophores may also be affected by anion variation. To explore this possibility, the authors have determined the influence of anion variation in competitive alkali metal cation extractions from aqueous solutions into chloroform by cis-syn-cis-dicyclohexano-18-crown-6 (1). The anion effect in solvent extraction of alkali metal cations by 1 was assessed by extracting aqueous solutions of Li[sup +], Na[sup +], K[sup +], Rb[sup +], and Cs[sup +] (0.020 M in each) having a common anion with an equal volume of a 0.010 M chloroform solution of the crown ether. The series of aqueous-phase anions (bromide, iodide, nitrate, perchlorate, and thiocyanate) was chosen to include both hard (e.g., nitrate) and soft (e.g., thiocyanate) anions. The overall extraction efficiency decreases in the order: perchlorate > iodide, thiocyanate > nitrate >more » bromide. On the basis of the concentration of crown ether, the total extraction efficiency ranges from 63% for competitive extraction of the alkali metal perchlorates to only 1.0% loading for extraction of the alkali metal bromides. 26 refs., 3 tabs.« less

Alkylated Lariat Ethers as Solvent Extraction Reagents: Surveying the Extraction of Alkali Metals by Bis-t-octylbenzo-14-crown-4-acetic Acid by Use of Potentiometric Two-Phase Titration

Abstract Two-phase potentiometric titrimetry was used to survey the extraction of alkali metal cations from aqueous chloride solution by the lipophilic, ionizable lariat ether bis-(t-octylbenzo)-14-crown-4-acetic acid (BOB14C4AA) in o-xylene. Analysis of the data indicates that ion-exchange extraction by the crown-carboxylic acid at low loading (i.e., low conversion of BOB14C4AA to its salt form) is stronger for lithium ion than for the other alkali metals. Little or no selectivity occurs at high loadings. In comparison with the long-chain carboxylic acid 2-methyl-2-heptylnonanoic acid (HMHN), BOB14C4AA extracts lithium and sodium at significantly lower pH; in the loading range of 0.1 to 0.7, the pH shift is 1.4–1.8 pH units for sodium ion and 1.7–2.3 pH units for lithium ion. The titration data are interpreted in terms of aggregated organic-phase species. In the case of lithium extraction, clear evidence was found for a species in which neutral BOB14C4AA participates in the organic-phase complexation of ...

Competitive solvent extraction of alkali metal cations into chloroform by lipophilic acyclic proton-ionizable polyethers

A series of lipophilic acyclic polyether carboxylic acids and a corresponding polyether phosphonic acid monoethyl ester were synthesized in which the unit that contains the lipophilic and the proton-ionizable groups is held constant, but the polyether chain and its terminal group are systematically varied. Competitive solvent extraction of alkall metal cations from aqueous solutions into chloroform was performed to assess the influence of structural variation within the extractant molecule upon the extraction selectivity and efficiency

Selective Transport of Alkali Metal Cations in Solvent Extraction by Proton-Ionizable Dibenzocrown Ethers

Abstract Lipophilic crown ethers with pendant proton-ionizable groups are novel metal complexing agents for use in solvent extraction of alkali metal cations. A variety of dibenzocrown ether carboxylic acids and dibenzo crown phosphonic acid monoesters have been examined to probe the effect of structural variation within the complexing agent upon selectivity and efficiency in solvent extraction. Results from competitive solvent extractions of alkali metal cations from aqueous solutions into chloroform are summarized.

Effect of solvent upon competitive liquid-liquid extraction of alkali metal cations by isomeric dibenzo-16-crown-5-oxyacetic acids

Effect of solvent upon competitive liquid-liquid extraction of alkali metal cations by isomeric dibenzo-16-crown-5-oxyacetic acids

EFFECTS OF STRUCTURAL VARIATION WITHIN PROTON-IONIZABLE CROWN ETHERS UPON THE SELECTIVITY AND EFFICIENCY OF SOLVENT EXTRACTION OF ALKALI METAL AND ALKALINE EARTH CATIONS

ABSTRACT Lipophilic crown ethers with pendant proton-ionizable groups are novel complexing agents for use in solvent extraction of alkali metal and alkaline earth cations. A variety of crown carboxylic acids, crown phosphonic acid monoesters, and crown phosphonic acids have been synthesized to probe the effect of structural variation within the complexing agent upon selectivity and efficiency in solvent extraction. Synthetic routes to these novel extractants and results from competitive solvent extractions of alkali metal cations and of alkaline earth cations from aqueous solutions into chloroform are summarized

Extraction of alkali metal cations into polyester-based polyurethane foam using crown ether and picric acid

The distribution of alkali metal picrates between water and polyester-based polyurethane foam in the presence of dicyclohexyl-18-crown-6 was studied. The order of extraction coefficients of the alkali metals is governed by the ratio of the cation size to that of the crown ether, although the degree of extraction may depend on the nature of the organic phase. The extraction of alkali metals by polyurethane foam from an aqueous solution in the presence of crown ether and a bulky anion can be considered as an ion pair extraction of MCrA by an organic solvent.

Effect of solvent upon competitive liquid-liquid extraction of alkali metal cations by 2-[(sym-dibenzo-16-crown-5)oxy]decanoic acid

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTEffect of solvent upon competitive liquid-liquid extraction of alkali metal cations by 2-[(sym-dibenzo-16-crown-5)oxy]decanoic acidWitold A. Charewicz, Wladyslaw. Walkowiak, and Richard A. BartschCite this: Anal. Chem. 1987, 59, 3, 494–496Publication Date (Print):February 1, 1987Publication History Published online1 May 2002Published inissue 1 February 1987https://doi.org/10.1021/ac00130a026RIGHTS & PERMISSIONSArticle Views77Altmetric-Citations43LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (393 KB) Get e-Alerts Get e-Alerts

Effect of sidearm length upon competitive alkali metal solvent extraction into chloroform by lipophilic crown phosphonic acid monoalkyl esters

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTEffect of sidearm length upon competitive alkali metal solvent extraction into chloroform by lipophilic crown phosphonic acid monoalkyl estersMichael J. Pugia, Grace. Ndip, Han Koo. Lee, Il Woo. Yang, and Richard A. BartschCite this: Anal. Chem. 1986, 58, 13, 2723–2726Publication Date (Print):November 1, 1986Publication History Published online1 May 2002Published inissue 1 November 1986https://doi.org/10.1021/ac00126a031RIGHTS & PERMISSIONSArticle Views122Altmetric-Citations29LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (510 KB) Get e-Alerts Get e-Alerts

Crown ether modified polyethyleneimine selective extraction of alkali metal cations from aqueous to organic phase

Die Makromolekulare Chemie, Rapid CommunicationsVolume 3, Issue 6 p. 399-403 Article Crown ether modified polyethyleneimine selective extraction of alkali metal cations from aqueous to organic phase Jun-ichi Anzai, Jun-ichi Anzai Pharmaceutical Institute, Tohoku University, Aobayama, Sendai 980, JapanSearch for more papers by this authorYoko Sakata, Yoko Sakata Pharmaceutical Institute, Tohoku University, Aobayama, Sendai 980, JapanSearch for more papers by this authorAkihiko Ueno, Akihiko Ueno Pharmaceutical Institute, Tohoku University, Aobayama, Sendai 980, JapanSearch for more papers by this authorTetsuo Osa, Corresponding Author Tetsuo Osa Pharmaceutical Institute, Tohoku University, Aobayama, Sendai 980, JapanPharmaceutical Institute, Tohoku University, Aobayama, Sendai 980, JapanSearch for more papers by this author Jun-ichi Anzai, Jun-ichi Anzai Pharmaceutical Institute, Tohoku University, Aobayama, Sendai 980, JapanSearch for more papers by this authorYoko Sakata, Yoko Sakata Pharmaceutical Institute, Tohoku University, Aobayama, Sendai 980, JapanSearch for more papers by this authorAkihiko Ueno, Akihiko Ueno Pharmaceutical Institute, Tohoku University, Aobayama, Sendai 980, JapanSearch for more papers by this authorTetsuo Osa, Corresponding Author Tetsuo Osa Pharmaceutical Institute, Tohoku University, Aobayama, Sendai 980, JapanPharmaceutical Institute, Tohoku University, Aobayama, Sendai 980, JapanSearch for more papers by this author First published: 15 June 1982 https://doi.org/10.1002/marc.1982.030030605Citations: 11AboutPDF 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 onFacebookTwitterLinkedInRedditWechat Citing Literature Volume3, Issue615 June 1982Pages 399-403 RelatedInformation

Solvent Extraction of Alkali Metal Cations from Aqueous Solutions by Crown Ether Carboxylic Acids

Abstract Competitive solvent extractions of alkali metal cations from aqueous solutions by the crown ether carboxylic acids sym-dibenzo-13-crown-4-oxyacetic acid, 2; sym-dibenzo-19-crown-6-oxyacetic acid, 3, and sym-dibenzo-14-crown-4-oxyacetic acid, 4, in chloroform have been conducted. Influences of aqueous phase pH and metal ion concentrations upon the concentrations of metals and complexing agent in the organic phase are assessed and compared with those reported for sym-dibenzo-16-crown-5-oxyacetic acid, 1. Extraction selectivity orders of K > Rb > Na ≍ Cs > Li, K > Rb ≥ Na ≍ Cs > Li, and K > Na > Rb > Cs ≍ Li were found for extractions using 2, 3, and 4, respectively. In terms of selectivity and metal extractability, 3 surpasses 1, 2, and 4.

Solvent extraction of alkali metal cations from aqueous solutions by highly lipophilic crown ether carboxylic acids

Competitive solvent extractions of alkali metal cations from water into chloroform by 2-(sym-dibenzo-16-crown-5-oxy)-butanoic acid (5), 2-(sym-dibenzo-16-crown-5-oxy)hexanoic acid (6), 2-sym-dibenzo-16-crown-5-oxy)octanoic acid (7), 2-(syn-dibenzo-16-crown-5-oxy)decanoic acid (8), and 5-(sym-dibenzo-16-crown-5-oxy)pentanoic acid (9) are reported. For 6, 7, and 8 the complexing agents are sufficiently lipophillic that they remain totally in the organic phase when chloroform solutions of the crown ether carboxylic acids are contacted with highly alkaline aqueous alkali metal salt solutions.

Extraction of alkali metal cations from aqueous solutions by a crown ether carboxylic acid

Solvent extraction of alkali metal cations from aqueous solutions by sym-dibenzo-16-crown-5-oxyacetic acid in chloroform is reported. Influence of pH, metal ion identity and concentration in the aqueous phase, and anion identity in the aqueous phase upon the concentrations of metal and complexing agent in the organic phase are assessed for single ion extractions. Extraction efficiency is insensitive to changing the aqueous phase anion from chloride to sulfate which demonstrates that the anion is not transferred to the organic phase during extraction. Extraction efficiency is very sensitive to the pH of the aqueous phase. For competitive ion extractions, the selectivity is K > Na > Rb greater than or equal to Cs > Li for pH 6 to 7 and Na > K > Rb approx. = Cs > Li for pH 8 to 12. The crown ether carboxylic acid exhibits extraction efficiencies and selectivities which surpass those of sym-dibenzo-16-crown-5 methyl ether or phenoxyacetic acid.