Effects of relative humidity and surface soiling on the sorption of organic pollutants to polymeric material

Effects of relative humidity and surface soiling on the sorption of organic pollutants to polymeric material


English :
We measured the partitioning coefficient (Kpart,substrate/air) for the sorption of gas-phase toluene, tetrachloroethylene and n-decane on both clean and soiled surfaces of polypropylene sheets under varying relative humidity (RH) using a small chamber. An individual 0.08-μL pure liquid chemical was introduced into the chamber by flash evaporating. Kinetic sorption parameters were determined by fitting measured time-dependent concentrations to the surface and embedded sink models using a MATLAB® genetic algorithm toolbox. Results show that the Kpart for toluene ranged from 102 to 103, while for tetrachloroethylene and decane varied from 100 to 102. When the RH increased, Kpart decreased for all sorbates. The toluene uptake appeared to be most affected by surface soiling. Kpart decreased by three times compared with Kpart for the clean surface under the same 50% RH.