Dissolution Model for a Weak Carboxylic Acid

Abstract

A chemical reaction, diffusion, and ionization model is presented for the dissolution of solid, weak acids in reactive media. The model assumes an equilibrium plane, which is located within the diffusion layer and in which ionization equilibrium is established. The model, which proposes that the aqueous diffusion layer is divided into three zones, is tested by use of experimental dissolution rates of p-aminobenzoic acid and is compared to a two-zone model.