Alkali cation transport by proton-ionizable macrocycles in a H2O–CH2Cl2–H2O bulk liquid membrane system

Abstract

Coupled H⁺–M⁺(M = Na, K, Rb, or Cs) transport of individual M⁺ and binary M⁺ mixtures in which K⁺ is transported selectively in a 1 M MOH–CH₂Cl₂–HNO₃/H₂O (pH 1.5 and ∼6) bulk liquid membrane system has been accomplished using a proton-ionizable 4-pyridone-fused-18-crown-6 macrocycle with an attached C₈H₁₇ chain (2).