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 studied 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 film as determined in a previous study at higher temperatures. For all tested substances, a decrease of adsorption was observed with increasing salt concentration in the ice. The surface of fresh ice was subject to an aging process which led to a decrease in the adsorption of the polar compounds. Measurements that were carried out after completion of this aging process showed an adsorption of the polar substances that was different from the adsorption on the surface of adsorbed water films. The adsorption behavior of volatile substances on the surface of a water film covering quartz sand did not change when experimental temperatures dropped below the freezing point.