Adsorption of volatile atmospheric pollutants on an heterogeneous surface of surrogate solid aerosols

Adsorption of 23 nonpolar and polar volatile atmospheric organic pollutants on the surface of silica gel, carbon black (Carbopack), and carbon-coated silica gel (Carbosil), materials imitating mineral and carbonaceous aerosols, was studied by inverse gas chromatography at finite concentrations. The results obtained suggest that the surface is nonuniform. The experimental adsorption isotherms were described within the framework of an approach based on the local Langmuir equation and a rectangular surface area distribution over the adsorption energy. It was established how the mean and variance moments of these distributions depend on the polarizability of the sorbates and their acid-base characteristics and how these parameters influence the adsorption characteristics of the system under study.