Hamamci, CHosgoren, HErdogan, S2024-04-242024-04-2419980039-9140https://doi.org/10.1016/S0039-9140(98)00082-4https://hdl.handle.net/11468/16244Extraction of alkali metal picrates with N,N'-dibenzyl-18-crown-6 was carried out, with dichloromethane as water-immiscible solvent, as a function [ligand]/[metal cation]. The extractability of metal picrates (Li+, Na+, K+ Rb+, Cs+) was evaluated as a function of [L]/[M+]. The extractability of complex cation-picrate ion pairs decreases in this sequence: Li+ > Rb+ > Cs+ > K+ > Na+. The overall extraction equilibrium constants (K-ex) for complexes of N,N'-dibenzyl-18-crown-6 with alkali metal picrates between dichloromethane and water have been determined at 25 degrees C. The values of the extraction constants (log K-ex) were determined to be 10.05, 6.83, 7.12, 7.83, 6.73 for Li+ Na+, K+, Rb+ and Cs+ compounds, respectively. DB186 shows almost 2-fold extractability against Li+ compared to the other metal picrates, whereas it shows no obvious extractability difference amongst the other metal cations when [L]/[M+] is 0.2-1. However, an increasing extractability is observed for Cs+ when [L]/[M+] [1]. (C) 1998 Elsevier Science B.V. All rights reserved.eninfo:eu-repo/semantics/closedAccessDiaza-Crown EtherSolvent ExtractionAlkali Metal PicrateArticle471229236WOS:0000766218000282-s2.0-03454042131896732210.1016/S0039-9140(98)00082-4Q1Q2