ISBN-13: 9783659259531 / Angielski / Miękka / 2012 / 124 str.
ISBN-13: 9783659259531 / Angielski / Miękka / 2012 / 124 str.
The present work was aimed at the development of clay-based composite as an adsorbent that it can be used in the removal of chlorophenols by adsorption to obtain equilibrium, kinetics and thermodynamic parameters. The bentonite were characterized by XRD, XRF, FTIR spectroscopy, SEM and EDS. The polymethylacrylate-bentonite nanocomposite were used to study their ability to scavenge chlorophenols from aqueous solutions. Equilibration time, pH effect and initial chlorophenols concentration preceded the detailed extraction study. The dynamic data fitted to the pseudo-second-order kinetic model well. The experimental data at three temperatures (25, 35 and 45 ±0.1 ºC) for the nanobentonite and polymethylacrylate-bentonite nanocomposite for the removal of chlorophenols were obtained. The Freundlich isotherm model agrees well with the equilibrium experimental data. The thermodynamic values of Gº are Positives in each system; indicating a nonspontaneous process. Negative value of Hº and Sº for polymethylacrylate-bentonite nanocomposite indicates an exothermic process and decrease of disorder of the process. The adsorption capacity for chlorophenols increase with the decrease of pH.