21.
Antunes A. M., Ferreira M. M. C., Melgo M. S., Volpe. P. L. O., “Potassium transport trough liquid membranes using spectral and chemometric methods”. J. Mol. Struct., 481(Special Issue SI), 563-567 (May 1999).
[Special issue Molecular Spectroscopy and Molecular Structure with contributions from EUCMOS XXIV, the 24th European Congress on Molecular Spectroscopy, held in Prague, Czech Republic on 23 - 28 August 1998. See Notes.]
[Article.]

Abstract.
Chemometric techniques were applied to follow the transport of potassium through a chloroform membrane, using ternary
mixtures of the isomeric anions, 2,4-dinitrophenolate (2,4-DNP) and 2,5-dinitrophenolate (2,5-DNP) with also
2-nitrophenolate (ortho-). Some spectral differences can be observed in the UV-Vis region, although 2,4- and 2,5-DNP have
very similar spectra. Using the trilinear decomposition method (TLD), it is possible to estimate the spectra of the pure
components and simultaneously their kinetic profiles. The estimated spectral profiles are in excellent agreement with
experimental results and the kinetic profiles agree with those obtained by ordinary least squares (OLS). The transport rates are
calculated and compared. The ortho- isomer has a very small rate of transport.

Keywords.
Chemometrics; Liquid Membranes; Trilinear Decomposition; Nitrophenolates.

Keywords Plus.
Facilitated transport.