ESTIMATING THE ACTIVATED CARBON ADSORPTION OF ORGANIC-CHEMICALS IN WATER

The adsorbtion of an organic chemical on activated carbon can be estim ated without experimentation by using either literature data or quanti tative structure activity relationships (QSARs). This review focuses o n the activated carbon adsorption of organic chemicals at low concentr ations applicable to water treatment or natural water. High variabilit y is found among the data in the six literature sources considered. Ho wever, high correlations often exist between the data in differing sou rces, implying that systematic differences and not just experimental i rregularities are responsible for the variability. QSARs relate adsorb tion to easily obtained chemical descriptors. They can be used for est imating the adsorbtion of a chemical that is similar to the chemicals upon which the QSAR is based. The 13 QSARs considered in this review u se methods based on octanol-water partition coefficients, Polanyi pote ntial theory, linear solvation energy relationships, molecular connect ivity, and other physical/chemical descriptors. The QSARs demonstrate a high potential for accurately estimating adsorption, but are limited by the high variability of the underlying literature data.