Dehydration of a polyether type extraction agent and of the corresponding K+ complex: insights into liquid-liquid extraction mechanisms by quantum chemical methods

• Type: Article in International Scientific Journal
• Date: 2012

Authors

Mario Valente (Author) Other; Sergio Filipe Sousa (Author) FCUP; Alexandre L Magalhaes (Author) FCUP; Cristina Freire (Author) FCUP

Journal

Title: Journal Of Molecular Modeling

Vol. 18 No. 11

Pages: 4909-4915

ISSN: 1610-2940

Publisher: Springer Nature

Indexing

ISI Web of Knowledge - 1 Citation

Scopus - 1 Citation

Scientific classification

FOS: Natural sciences > Chemical sciences

Other information

Authenticus ID: P-002-435

DOI: 10.1007/s00894-012-1491-3

Abstract (EN): In this paper we report a quantum chemical study performed at the B3LYP/6-311G++(d,p) level of theory on structural and energetic aspects of the sequential dehydration of a tetra-hydrated polyethylene-glycol type podand (1,2-bis-{2-[2-(2-methoxy-ethoxy)-ethoxy]-ethoxy}-benzene, hereafter b33) and its complex with the K+ cation. Thermodynamical parameters were determined by hessian quantum calculations performed using a self-consistent reaction field (SCRF) method, taking into account solvent (dichloromethane) effects. The results allowed the estimation of dehydration enthalpies, entropies and free energies for the hydrated free b33 podand and its corresponding K+ cation complex in dichloromethane. The low absolute values found for the dehydration free energies as well as the structural features found for the optimized structures and the corresponding basis superposition calculated interaction energies, support the hypothesis of an interfacial complexation type mechanism governing the assisted extraction of K+ from an aqueous toward an organic phase, in liquid/liquid extraction.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 7