Preconcentration of gaseous organic pollutants in the atmosphere

Three basic methods of preconcentration of organic atmospheric pollutants, viz. by cold trap, absorption in solutions and adsorption on solids at ambient temperature, and methods of liberating the trapped components, are discussed. Adsorption on solids is becoming more widely employed because of its advantages, and selection of the most appropriate sorbent for a given group of pollutants is of major importance. The characteristics of individual types of sorbents are presented, as well as the basic methods of determination of sorption capacity.