Effect of pH of Medium and Initial Salt Quantity on Release Behaviour of Potassium Chloride from Leached Poly(vinyl alcohol)/Glutaraldehyde

Abstract

The purpose of present work is to study the release kinetics of KCl from leached poly(vinyl alcohol)/glutaraldehyde (PVA/GA) hydrogelsinto demineralized water under various pH conditions. The PVA/GA hydrogels, which was prepared by mixing method, were leachedseveral times using demineralized water. The physico-chemical properties of the hydrogels were investigated using FT-IR and SEMtechniques. The release kinetics of KCl from the hydrogel into the demineralized water at various pH conditions and initial quantity ofKCl inside the hydrogel were studied using conductometric method. It was found that the trapped residual inside the hydrogel matrix can be well removed by repeated leaching. The pH of medium affects the rate of release and the amount of KCl at equilibrium conditions. The kinetics of KCl desorption into the media follows pseudo first-order kinetics, which indicates that the release kinetics is controlled by the initial amount of KCl in the PVA/GA matrix.