Kinetic and equilibrium studies of cesium-137 adsorption on olive waste from aqueous solutions

The agricultural by-product, olive pomace, in its raw or carbonized form was used for the removal of 137Cs from aqueous solutions. Experimental studies were conducted to evaluate and optimize such factors as the contact time, adsorbent dosage, pH, and initial 137Cs concentration. The sorption process was described by the pseudo-first-order, pseudo-second-order, and intraparticle diffusion models. Data were interpreted in terms of Langmuir, Freundlich, and Dubinin-Radushkevich (DR) isotherms. The data obtained show that 120 min is sufficient time to attain the equilibrium. The maximum removal of 137Cs was found to be 80 and 99% with raw olive pomace and its carbonized form, respectively. The maximum sorption capacity of the raw and carbonized adsorbent for cesium was 0.360 and 0.565 mol g-1, respectively. © 2013 Pleiades Publishing, Inc.