Chemometric methods for description and analysis of membrane phenomena. I. Effect of organic solvent on pertraction of benzoic acid

Pertraction of benzoic acid in a bulk liquid membrane (BLM) composed of hexane, heptane, octane, nonane, decane, dodecane or isooctane was studied and interpreted using the chemometric methods. Six selected physicochemical properties (density, boiling point, melting point, dielectric constant, refractive index, viscosity) or six topological indices (the Wiener number, zero-order connectivity index, fourth-order connectivity index, superpendentic index, first Zagreb index) were linearly correlated with experimentally measured fluxes. The quality of modelling was evaluated by a standard regression analysis and cross-validation procedure. It was found that the application of topological connectivity indices enable exceptionally good quantitative description and prediction of benzoic acid pertraction efficiency. For example, the empirical linear relation in which the fourth-order connectivity index has been applied is sufficient for describing over 97% of the total variance between the fluxes of benzoic acid and the type of an organic solvent (characterized by the topological index).