Critical parameters for the adsorption of gaseous pollutants on passive samplers made of low specific area adsorbents

The parameters affecting the sampling on passive samplers made of graphitized carbon black, an adsorbent with a low specific area, are investigated. It has been shown that a reverse diffusion might occur, this effect being more noticeable for volatile compounds. Also, the presence of organics in large concentration may affect the sampling of components in small concentration due to a deactivation of the adsorbent. These limitations are counterbalanced if the passive samplers have a suitable geometry and contain a sufficient amount of adsorbent.