(337d) Interfacial Tension in Multiphase, Highly Supersaturated Aqueous Solutions for CaCO3 Polymorphs

A method of modelling the interfacial energy of CaCO3 particles in a supersaturated, aqueous solution will be presented. Four polymorphs of CaCO3 will be considered, each with its own distinct surface properties. The purpose of this model is for the application to nucleation, growth, and agglomeration kernels in a population balance in order to reproduce experimental data from the literature [Ogino et al., Geochimica et Cosmochimia Acta, 1987]. The system described by the literature varied in temperature and the supersaturation of the measured solutions changed over time.

All three of the physical processes effecting the evolution of the particle distribution are functions of and sensitive to the interfacial tension of the particle-solution interface. Interfacial tension itself is a function of both temperature and the ionic composition of the fluid surrounding the particle, thus making this a dynamic system. The interfacial tension between phases can generally be modelled using the van Oss & Good equation, which breaks up the surface tension of each phase into polar and non-polar components and then combines these phases components to find the interfacial tension. The effect of the temperature and varying amounts of multiple ionic compounds within the aqueous solution will be considered and incorporated in the components water’s surface tension.