Akçay, GAkçay, MYurdakoç, K2024-04-242024-04-2420050021-97971095-7103https://doi.org/10.1016/j.jcis.2004.08.080https://hdl.handle.net/11468/15591The adsorption of 2,4-dichlorophenoxyacetic acid (2,4-D) on organophilic sepiolite (dodecylammonium sepiolite, DAS) was Studied as a function of solution concentration and temperature. The observed adsorption rates were found to be equal to the first-order kinetics. The rate constants were calculated for temperatures ranging between 25 and 40 degreesC at constant concentration. The adsorption energies, E. and adsorption capacity, q(m), for 2,4-D adsorption on organophilic sepiolite was estimated using the Dubinin-Radushkevic equation. Thermodynamic parameters (Deltag(a), Deltah(a), Deltas(a)) were determined by a new approximation from the isotherm of 2,4-D adsorption on DAS. Also, DeltaS(0) and DeltaH(0) values were calculated from the van't Hoff equation. These isotherms were modeled according to the Freundlich and Dubinin-Radushkevic adsorption equations. The amount of adsorption of this herbicide on organophilic sepiolite was found to be dependent on the relative energies of adsorbent-adsorbate, ad sorbate-sol vent, and adsorbate-adsorbate interaction. (C) 2004 Elsevier Inc. All rights reserved.eninfo:eu-repo/semantics/closedAccessHerbicidesRemovalAdsorptionThermodynamicsKineticsOrganophilic SepioliteArticle28112732WOS:0002256596000042-s2.0-96442816181556737610.1016/j.jcis.2004.08.080Q1Q2