A PREDICTION METHOD FOR GAS-PHASE VOC ISOTHERMS ONTO SOILS AND SOIL CONSTITUENTS

Similarities in the adsorption isotherms of various non-polar volatile organic chemicals (VOCs) on dry soils and clay minerals are used to d evelop an empirical predictive method to estimate the isotherm paramet ers of the BDDT (three-parameter BET) model. Single-component adsorpti on data of nine VOCs on both soils and clay minerals and also nitrogen adsorption are examined. The familiar practice of reducing isotherms by the BET monolayer coverage is applied, and it is shown that isother ms of different VOCs on the same adsorbent collapse into a single isot herm. A simple prediction method based on this observation is presente d.