ABSTRACT
The stripping rate of propionic acid from microcapsules containing tri-n-octyl amine was investigated using distilled water and aqueous NaOH as stripping solutions. The experiments were conducted at 303K. The stripping rate was found to be controlled by diffusion through porous microcapsule membrane and increased with an increase in the concentration of propionic acid in the microcapsules for each solution system. It was found that the stripping rates in aqueous NaOH solution system was higher than in distilled water at the same concentration of propionic acid in microcapsules. The experimental results in the NaOH solution system could be analyzed using a permeation model considering mass transfer accompanied by irreversible instantaneous neutralization reaction between NaOH and the propionic acid/tri-n-octyl amine complex in the microcapsule membrane.