Temperature effects during Ostwald ripening

Temperature influences Ostwald ripening through its effect on interfacial energy, growth rate coefficients, and equilibrium solubility. We have applied a distribution kinetics model to examine such temperature effects. The model accounts for the Gibbs-Thomson influence that favors growth of larger particles, and the dissolution of unstable particles smaller than critical nucleus size. Scaled equations for the particle size distribution and solution concentration as functions of time are solved numerically. Moments of the distribution show the temporal evolution of number and mass concentration, average particle size, and polydispersity index. Parametric and asymptotic trends are plotted and discussed in relation to reported observations. Temperature programming is proposed as a potential method to control the size distribution during the phase transition. We also explore how two crystal polymorphs can be separated by a temperature program based on different interfacial properties of the crystal forms. (C) 2003 American Institute of Physics.