Study of the direct fitting of a nanofiltration model using model solutions of different ionic complexity

Autores UPV
Año
CONGRESO Study of the direct fitting of a nanofiltration model using model solutions of different ionic complexity

Abstract

Nanofiltration (NF) is an effective technique for desalination of brackish waters. To further develop NF processes, a deeper knowledge of the mechanisms that are involved in the separation is needed, being models based on the use of the Nernst-Planck equation of great help in this purpose. One of these models is the Donnan steric-partitioning pore model with dielectric exclusion (DSPM-DE) [1]. The determination of the model parameters is a critical step. Although there is special interest in obtaining NF models with parameters based on measurable properties of the membrane and independent from feed and operating conditions, many times, from a practical point of view, NF parameters can be directly fitted from experimental data. Therefore, deciding how many and what type of experiments are needed to obtain this information seems to be an appropriate new approach. This works is focused on the study of the effect of the ionic complexity of the model solutions used for fitting the DSPM-DE model on the prediction of NF performance. For this purpose, the experimental behavior of a validation case was compared with the one predicted by the model fitted using experimental results with different sets of salt solutions of different ionic composition complexity. Fittings and predictions with different number of salts and levels of applied pressure and total concentration were performed in order to know if more information yields to a better prediction of the validation case even mantaining a low number of experiments.