Determination of Distribution Equilibrium-Potential Differences Based on Extraction with Several Crown Ethers by Nitrobenzene, 1,2-Dichloroethane and Dichloromethane

  •  Yoshihiro Kudo    
  •  Tomohiro Amano    
  •  Satoshi Ikeda    


Extraction constants (Kex± & Kex) were determined at 298 K for the extraction of sodium picrate (NaPic) by nitrobenzene (NB), 1,2-dichloroethane (DCE) and dichloromethane using 3m-crown-m ethers and their benzo-derivatives (m = 5, 6; abbreviated as L) together with the determination of conditional distribution constants (KD,Pic) of picrate ion, Pic-, into these diluents. The K1,org (= [NaLPic]org/[NaL+]org[Pic-]org) values at the organic (org) phases, such as NB & DCE, were calculated from the relation Kex/Kex± = K1,org. Distribution equilibrium-potential differences (Dfeq) at extraction equilibria were evaluated from the equation Dfeq = -0.05916´(log KD,Pic - constant) at 298 K. Correlations of the above equilibrium constants, particularly Kex±, with Dfeq were examined. Furthermore, the standard formal potentials for Na+ transfers across the interfaces were briefly evaluated from calculated Dfeq, [Na+] and [Pic-]org. The above extraction systems were characterized by K1,org and the complex formation constants of Na+ with L in the org phases.

This work is licensed under a Creative Commons Attribution 4.0 License.
  • Issn(Print): 1916-9698
  • Issn(Onlne): 1916-9701
  • Started: 2009
  • Frequency: quarterly

Journal Metrics

Google-based Impact Factor (2018): 10.07

h-index (August 2018): 23

i10-index (August 2018): 76

h5-index (August 2018): 9

h5-median(August 2018): 14

( The data was calculated based on Google Scholar Citations. Click Here to Learn More. )