The effect of H2O adsorption on cloud drop activation of insoluble particles: a theoretical framework
Cloud droplet activation of wettable insoluble compounds has been studied theoretically by assuming that droplet growth happens through multilayer adsorption. The idea is to include an adsorption isotherm in K¨ ohler theory instead of the solute term. This makes it possible to de- scribe the equilibrium growth of insoluble particles and to find out their critical saturation ratios. The critical satura- tion ratios calculated in this way are comparable to those of completely soluble particles at certain ranges of adsorption isotherm parameter values. The results indicate that adsorp- tion could cause wettable insoluble compounds to activate in atmospheric conditions. However, more data on the adsorp- tion parameters for wettable organic substances is needed to confirm this conclusion.