Desiccant Moisture Sorption as Altered by Dust

THE moisture sorption characteristics of silica gel, activated alumina and a molecular sieve each having 0 percent and 5 percent dust were compared. Inorganic dust particles of 10 to 20 micrometers did not affect the equilibrium moisture content of either silica gel, ac-tivated alumina or molecular sieve. Dynamic moisture sorption rates of all three desiccants were reduced by dust contamination. The molecular sieve adsorbs moisture rapidly until saturation, unlike that described by the common falling rate sorption model. While silica gel and activated alumina may be useful in drying air for agricultural applications, the molecular sieve is least likely to be useful due to its low hygroscopic capacity.