Phenol adsorption in organo-modified basaltic clay and bentonite

An assessment of the adsorption of phenol by four organically modified clays created from the base basaltic clay and bentonite, respectively, indicates that the modest degree of modification employed resulted in an increase in adsorption coefficient from the base clays of approximately 2 orders of magnitude for HDTMA-Basaltic and TMPA-Bentonite and an increase of approximately one order of magnitude for HDTMA-Bentonite and TMPA-Basaltic. Phenol adsorption to HDTMA modified clays could be described by a linear Freundlich equation while adsorption to the TMPA modified clays was better described by the Langmuir equation. The adsorption studies conducted indicate that a significant increase in organic compound adsorption capacity can be achieved for smectite clay minerals by modest and simple organic modification. However, the study did identify that adsorption parameters obtained from one concentration range may not describe adsorption over a different concentration range. For this reason batch adsorption tests should be conducted over the concentration range expected in the application.