TITLE:
On an Expression of Extraction Constants without the Interfacial Equilibrium-Potential Differences for the Extraction of Univalent and Divalent Metal Picrates by Crown Ethers into 1,2-Dichloroethane and Nitrobenzene
AUTHORS:
Yoshihiro Kudo, Shoichi Katsuta
KEYWORDS:
Extraction Constants, Distribution Constant of a Single Ion, Interfacial Equilibrium-Potential Differences, 1, 2-Dichloroethane, Nitrobenzene, Metal Picrates, Crown Ethers
JOURNAL NAME:
American Journal of Analytical Chemistry,
Vol.6 No.4,
March
27,
2015
ABSTRACT: An idea on
interfacial equilibrium-potential differences () which are generated for the extraction of
univalent metal picrate (MPic) and divalent ones (MPic2) by crown
ethers (L) into high-polar diluents was improved. These potentials were
clarified with some experimental extraction-data reported before on the M =
Ag(I), Ca(II), Sr(II) and Ba(II) extraction with 18-crown-6 ether (18C6) and
benzo-18C6 into 1,2-dichloroethane (DCE) and nitrobenzene (NB). Consequently,
it was demonstrated that the values from the extraction-experimentally obtained
logKD,Pic ones are in
agreement with or close to those calculated from charge balance equations in
many cases, where the symbol, KD,Pic,
denotes an individual distribution constant of Pic﹣ into the DCE or
NB phase. Also, it was experimentally shown that extraction constants based on
the overall extraction equilibria do not virtually contain the terms in their functional
expressions.