title: Iron(III) extraction from chloride media by N,N'-tetrasubstituted malonamides: an interfacial study.
abstract: The interfacial behaviour of two N,N'-tetrasubstituted malonamides, N,N'-dimethyl-N,N'-diphenyl malonamide (DMDPHMA) and N,N'-dimethyl-N,N'-dicyclohexylmalonamide (DMDCHMA), in the liquid-liquid (L/L) extraction of iron(III) from hydrochloric acid solutions, was studied. The experimental results obtained validate the absence of third phases for these systems. The equilibrium adsorption constants and surface excess concentrations, estimated by the Szyszkowski model, explain the experimental extraction efficiency patterns for both malonamides in the two diluents tested, 1,2-dichloroethane (1,2-DCE) and toluene. A solvation type mechanism is in accordance with all the results obtained, accounting for the structural and diluent effects observed.
authors.affiliation: Centro de Química e Bioquímica (CQB), Departamento de Química e Bioquímica, Faculdade de Ciências da Universidade de Lisboa (DQB-FCUL), Rua Ernesto de Vasconcelos, Edifício C8, 1749-016 Lisboa, Portugal. Electronic address: mssantos@fc.ul.pt.
authors.forename: M Soledade C S
authors.initials: MS
authors.lastname: Santos
authors.forename: Ana Paula
authors.initials: AP
authors.lastname: Paiva
keywords: Interfacial tension; Iron(III) extraction from chloride media; N,N′-tetrasubstituted malonamides; Structural and diluent effects