ADSORPTION-ISOTHERMS FOR CHLORINATED PHENOLS ON ACTIVATED CARBONS

The adsorption of 12 mono-, di-, and trichlorophenols from aqueous sol utions on different activated carbons was studied. Distilled water and a minimal salt medium solution previously used in biotreatment studie s with anaerobic organisms were used as solvents. A commercially avail able wood-based activated carbon (Chemviron carbon) and a lignite-base d carbon produced at Queen's University were used as the adsorbents. T he Chemviron carbon was used in both granular and powder forms. The ad sorption data for each chlorophenol were regressed using the Freundlic h equation. The fit was generally satisfactory, especially since the r ange of chlorophenol concentrations tested in this work extended over 6 orders of magnitude. The exponents of the chlorophenol concentration term in the Freundlich equations were found to be in the relatively n arrow range 0.127-0.207. Therefore an attempt was made to regress all the data for all chlorophenols using a single isotherm, and a cumulati ve Freundlich isotherm was obtained. The Chemviron carbon was found to have a higher adsorbing capacity than the lignite-based carbon. The p resence of additional inorganic solutes in the aqueous phase was found to have a negligible influence on adsorption.