INTERACTION OF AIRBORNE PARTICLES WITH GASES

A promising method for making sorption measurements in aerocolloidal systems is described. Initial studies are being conducted on the interaction of sulfur dioxide with metal oxide aerosols. The latter are generated by exploding metal wires in air, resulting in particles with diameters from about 0.01 to 0.1 micron. These are mixed with S35-labeled SO2 at controlled conditions in an 820-liter cylindrical chamber. Samples for analysis are withdrawn through diffusion tubes lined with leadperoxide- coated lead foil and followed by membrane filters. Diffusion tube analysis of several SO2-aerosol mixtures indicated that this is a possible method of distinguishing between chemisorption and physical adsorption. In measurements that included an adsorption isotherm for SO2 on iron oxide aerosol, preferential chemisorption on iron oxide and aluminum oxide was observed at low SO2 concentrations and was followed by multilayered physical adsorption at higher concentrations. © 1969, American Chemical Society. All rights reserved.