ChemInform Abstract: Uncommon Complex Stoichiometry in Solvent Extraction: Solution‐Phase Dicationic Complex Formation of Crown Ethers.

Inoue, Yoshihisa; Liu, Y.; Amano, Fumie; Ouchi, Mikio; Tai, Akira; Hakushi, Tadao

doi:10.1002/chin.198909066

Cited by 1 publication

(1 citation statement)

References 1 publication

Supporting

Mentioning

Contrasting

Order By: Relevance

“…When dissociation of LMPi in the organic phase is neglected, the calculated value of K ex becomes too large, particularly when dilute solutions are partitioned and K A (LMPi) is small. Calculation of the crown ether concentration in both phases using the partition coefficient, P c (L), has been described by Inoue et al (1988). The following relations, regarding MPi to be completely dissociated in water, were used:…”

Section: Solubility and Partition Constants Of Ligandsmentioning

confidence: 99%

Crown Ether Complexed Alkali Metal Picrate Ion Pairs in Water-Saturated Dichloromethane As Studied by Electrolytic Conductance and by Partitioning into Water. Effect of Lithium Chloride on Partitioning

and

Chantooni

1997

J. Chem. Eng. Data

View full text Add to dashboard Cite

The equilibrium constant of extraction of lithium, sodium, or potassium picrates, MPi, with 18-crown-6 or dibenzo-18-crown-6 between water and dichloromethane was determined spectrophotometrically and compared with literature values. In all instances, a 1:1:1 complex was extracted. The value of the ionic association constant of the complexed potassium picrate in the organic phase agrees well with that from electrolytic conductivity data. The latter reveals the presence of both cationic and anionic ion triplets in solutions >3 × 10-3 mol-1 dm-3. The effect of temperature on the solubility of dibenzo-18-crown-6 in water saturated with dichloromethane yields ΔH = −16.4 kJ mol-1 and ΔS = −36.02 kJ mol-1 K-1. Values of the activity coefficient of dibenzo-18-crown-6 at 298.1 K (“salting out effect”) in aqueous lithium chloride (0.10 to 0.25 mol dm-3) were estimated from the effect of the salt on the solubility, while the activity coefficient of the crown ether in dichloromethane saturated with water was evaluated from the effect of the salt on the partition coefficient. An estimate of the activity coefficient product, y(K+)y(Pi-), in the aqueous lithium chloride solutions was made from the effect of this electrolyte on the extraction constant.

show abstract

Section: Solubility and Partition Constants Of Ligandsmentioning

confidence: 99%