Kinetics of Phenol and Aniline Adsorption and Desorption on an Organo-Clay

Abstract

The use of organo-clays in wastewater treatment, as alternatives to activated C for sorbing pollutants, and in clay liners is of great interest to soil and environmental scientists. There is a lack of information, however, on the kinetics and mechanisms of organo-clay interactions with pollutants. Accordingly, in this study, the time-dependent adsorption and desorption of phenol and aniline on hexadecyltrimethylammonium-montmorillonite (HDTMA-Montmorillonite) from aqueous solutions were determined in a stirred-flow chamber. The experiments were conducted at two concentration levels, 0.001 and 0.01 mol L-1 for aniline, phenol, and their mixed solutions. Carbon-labeled (14C) solutes were used in the study. Adsorption of both phenol and aniline was completed within 40 min and desorption in 20 min. When the sorptives were mixed, the rates of adsorption-desorption were not significantly affected. The rate of phenol adsorption was influenced by sorptive concentration while the rate of aniline adsorption was independent of sorptive concentration. Various mechanisms appear to be involved in the adsorption processes.