FORMATION OF BI- AND POLYMODAL DISTRIBUTIONS AND THE NON-OSTWALD BEHAVIOR OF DISPERSE SYSTEMS

Consideration has been given to distinctive features of the infl uence of the chemical and phase composition of a dispersed phase, and also of external conditions on equilibrium size distributions of evaporating solution droplets containing a nonvolatile sparingly soluble component. Equilibrium radii of droplets containing a solid phase or a supersaturated solution have been described on the basis of Kelvin and Freundlich equations and Raoult′s law. Conditions have been shown under which the non-Ostwald behavior of the dispersed phase (mass transfer from large drops to small droplets) develops. Using the model distribution as an example, the possibility of the unimodal distribution transforming into a polymodal one has been demonstrated. A maximum separation of the fractions in the distribution is attained if the partial pressure of a volatile component exceeds the pressure of a vapor above a saturated solution.
   
Author:  V. B. Fedoseev and E. N. Fedoseeva
Keywords:  disperse system, aerosol, mist, size distribution, supersaturated solution, dimensional effect, evaporation, crystallization
Page:  1191