ADSORPTION OF ORGANIC VAPORS ON ICE AND QUARTZ SAND AT TEMPERATURES BELOW 0-DEGREES-C

The adsorption of volatile organic compounds at low temperatures was s tudied on ice with different salt concentrations and on quartz sand. A chromatographic method was applied which allowed measurements at very low concentrations. The observed adsorption of the nonpolar compounds on ice was comparable to the adsorption on the surface of a water fil m as determined in a previous study at higher temperatures. For all te sted substances, a decrease of adsorption was observed with increasing salt concentration in the ice. The surface of fresh ice was subject t o an aging process which led to a decrease in the adsorption of the po lar compounds. Measurements that were carried out after completion of this aging process showed an adsorption of the polar substances that w as different from the adsorption on the surface of adsorbed water film s. The adsorption behavior of volatile substances on the surface of a water film covering quartz sand did not change when experimental tempe ratures dropped below the freezing point.