DETERMINATION OF NUCLEATION AND GROWTH-RATES FROM INDUCTION TIMES IN SEEDED AND UNSEEDED PRECIPITATION OF CALCIUM-CARBONATE

Theoretical expressions for the supersaturation dependence of the induction time in seeded and unseeded precipitation are derived for different mechanisms of crystallite growth. On the basis of the theory a combined analysis of the induction time in both seeded and unseeded precipitation is presented, which allows separate determination of the nucleation and growth rates. Induction times in both seeded and unseeded precipitation of calcium carbonate in the absence and presence of additives are measured and interpreted in the light of the proposed theory. The analysis provides full information about the growth and nucleation rates in the investigated systems.