Retardation of dissolution and growth of calcium oxalate monohydrate

The kinetics of dissolution and growth of calcium oxalate monohydrate were examined in the presence of small concentrations of pyrophosphate, chlorophyll, and other agents. Data presented show that the retardation in mass transport in both processes is controlled by the nature of the additive, its concentration, and the way the additives are combined in the dissolution medium. Dissolution was studied using a particle counter method, and growth was conducted in a gel system under the slow diffusion of the reacting ions. Results obtained show that chlorophyll is more active than other inhibitors studied and suggest a higher surface adsorption intensity on the primary sources of the crystal surface.