Measurement of self-association and ion-pair dissociation constants by solvent extraction using a membrane phase separator

1982 ◽  
Vol 60 (11) ◽  
pp. 1286-1290 ◽  
Author(s):  
Murray Carmichael ◽  
Frederick F. Cantwell
Keyword(s):  
Solvent Extraction ◽  
Methylene Chloride ◽  
Dissociation Constants ◽  
Extraction Constant ◽  
Ion Pair ◽  
Membrane Phase ◽  
Dimerization Constant ◽  
Self Association ◽  
Phase Separator ◽  
Extraction Isotherms

The "filter-probe" membrane phase separator is used with a gravimetric buret to obtain the following constants at 25 °C by measuring solvent-extraction isotherms: dimerization constant of benzoic acid in chloroform (log K2,HBz = 2.12 ± 0.01); "self-ion-pair extraction" constant of Naloxone into chloroform [Formula: see text]; and ion-pair dissociation constant of tetraethylammonium picrate in methylene chloride (log Kdiss = −4.52 ± 0.09).

The extraction of alkali metal picrates by polyurethane foam using crown ether

1981 ◽  
Vol 59 (10) ◽  
pp. 1490-1496 ◽  
Author(s):  
Anjum S. Khan ◽  
W. G. Baldwin ◽  
A. Chow
Keyword(s):  
Crown Ether ◽  
Alkali Metal ◽  
Polyurethane Foam ◽  
Dissociation Constants ◽  
Extraction Constant ◽  
Ion Pair ◽  
Constant Sequence ◽  
Extraction Constants ◽  
The Stability ◽  
Ether Complex

The distribution of alkali metal picrates between water and polyurethane foam was studied in the presence of dicyclohexyl 18-crown-6 (DCHC-6). The extraction constants and dissociation constants for the ion pair (MCrA) in polyurethane foam were determined. The extraction constant sequence of the alkali metal ions with DCHC-6 is K+ > Rb+ > Cs+ > Na+ and mainly depends on the stability of the alkali metal – crown ether complex.

Use of peak height for quantification in solvent extraction/flow injection analysis

1985 ◽  
Vol 63 (9) ◽  
pp. 2559-2563 ◽  
Author(s):  
Jamal A. Sweileh ◽  
Frederick F. Cantwell
Keyword(s):  
Solvent Extraction ◽  
Flow Rate ◽  
Flow Injection Analysis ◽  
Peak Height ◽  
Membrane Phase ◽  
Flow Rates ◽  
Organic Extract ◽  
Sample Concentration ◽  
Band Dispersion ◽  
Phase Separator

The following equation is derived which expresses peak height (P.H.) in terms of sample concentration injected (CSAMP), detector sensitivity (SF), dilution due to band dispersion (Rv), fraction extracted [Formula: see text], flow rates of carrier (FCarrier), organic phase (Fo), and compensating solvent (Fc), and flow rate of organic extract through the membrane phase separator (FM):[Formula: see text]Each term in the equation is evaluated experimentally to validate the equation.

scholarly journals Porous membrane phase separator in solvent extraction.

1987 ◽  
Vol 3 (6) ◽  
pp. 583-584 ◽  
Author(s):  
Kousaburo OHASHI ◽  
Syozo KOKUBO ◽  
Shohei TAMURA ◽  
Katsumi YAMAMOTO
Keyword(s):  
Solvent Extraction ◽  
Porous Membrane ◽  
Membrane Phase ◽  
Phase Separator

Comparison of Sorption and Extraction Methods for Recovery of Trace Organics from Water

1983 ◽  
Vol 15 (6-7) ◽  
pp. 149-159 ◽  
Author(s):  
V C Blok ◽  
G P Slater ◽  
E M Giblin
Keyword(s):  
Solvent Extraction ◽  
Methylene Chloride ◽  
Extraction Methods ◽  
Liquid Extraction ◽  
Standard Mixture ◽  
Liquid Liquid Extraction ◽  
Trace Organics ◽  
Tenax Gc

Several commercially available adsorbents were compared with solvent extraction methods for their utility in recovering trace organics from water. The adsorbents examined included Amberlite XAD-2, XAD-4 and XAD-8, Ambersorb XE340 and XE348 and Tenax-GC. All were found to produce high artifact levels, even after extensive clean-up, making them unsuitable for the analysis of trace organics in water. Quantitatively, Likens-Nickerson or continuous liquid-liquid extraction with méthylene chloride gave better recoveries than the adsorbents. Qualitatively, extractive methods were preferred as they yielded much lower levels of impurities than the adsorbents. These methods of recovering trace organics were evaluated using a standard mixture of compounds added to the water at a level of 55 µg/l. Likens-Nickerson extraction gave comparable recoveries of this mixture at 55 µg/l and 11 µg/l.

scholarly journals Evaluation of the Hydrophilic Property of Sodium Ion-pair Complexes with 3m-Crown-m Ethers (m = 5, 6) and Their Benzo-derivatives by Solvent Extraction

2008 ◽  
Vol 24 (8) ◽  
pp. 999-1003 ◽  
Author(s):  
Yoshihiro KUDO ◽  
Ryo FUJIHARA ◽  
Toshiaki OHTAKE ◽  
Shoichi KATSUTA ◽  
Yasuyuki TAKEDA
Keyword(s):  
Solvent Extraction ◽  
Ion Pair ◽  
Sodium Ion ◽  
Hydrophilic Property
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