Ion transfer at liquid|liquid interfaces

R.A. IGLESIAS; S.A. DASSIE

Electroanalytical Chemistry: New Research

Nova publishers

Lugar: New York; Año: 2008; p. 119 - 185

In this review article, the main aspects related to the ion transfer reactions occurring at the interface between two immiscible electrolyte solutions (ITIES) are described. The particular topics to be discussed involve simple and assisted ion transfer and chemical reactions coupled to ion transfer. The focus is on theoretical approaches, numerical simulations and experimental methodologies. Concerning the theoretical approaches, different computational simulations related to simple and assisted ion transfer are reviewed. The main conclusions drawn from the most widely accepted models are described and analyzed in regard to their relevance to explain different aspects of ion transfer.             We describe numerical simulations implementing two different approaches, Laplace transform and finite difference techniques, for solving the differential equations associated with the mass transport and charge transfer. Different processes are explained; i.e. ion transfer assisted by the protonatable neutral ligand or protonated species and metal-ligand complexation with special emphasis on competitive transfer of different cations or ligands. These numerical simulations are correlated with selected experimental results and a summary of their usefulness for the design of new experiments is presented.             Regarding the experimental approaches, a brief description of the most commonly used experimental techniques is given. Several experimental results are reviewed and classified on the basis of the different ion transfer mechanisms.             Finally, many practical applications can be envisaged for the determination of physicochemical properties, electroanalysis, polymerization, phase-transfer catalysis, electro-assisted extraction and metallic nanoparticles synthesis and characterization.