Sorption equilibria of pyridine derivatives in aqueous solution on porous resins and ion exchange resins.

Abstract

Studies have been made of the sorption equilibria of pyridine, picoline and lutidine in aqueous solution on ion-exchange and porous resins. The sorption behaviors of these pyridines on strong acid ion-exchange resin can be expressed by the Langmuir isotherms, and those on both weak acid ion-exchange and porous resins by the Freundlich isotherms. The sorption mechanisms followed either a neutralization reaction with the H-form ion-exchange resins, or a hydrophobic interaction with the porous resins. Methanol content of the aqueous solution as well as solution pH was found to have a significant effect on the sorption of pyridines.Furthermore, the separations of these pyridines from each other were examined for three binary solute solutions in a batch mode. The pyridines were sorbed preferentially on the resins in the following sequence:pyridine where the selectivity increased as follows:strong acid ion-exchange resin