Modeling of the dissolution of calcium hydroxyde in the preparation of hydroxyapatite by neutralization

In order to control the properties of hydroxyapatite particles, the method based on neutralization of a suspension of lime with orthophosphoric acid i s studied. The dissolution of lime is the first step in the process and is described here. After a preliminary study of the hydrodynamics of the react or, a kinetic model, based on diffusion theory; was developed. It describes the increase of calcium concentration in a dynamic system. The effects of stirring rate, temperature and acid flow rate on the dissolution of lime we re determined experimentally. The acid flow rate influenced the reaction ra te the most. (C) 2000 Elsevier Science Ltd. All rights reserved.