RESUMEN
Removal of heavy metals from wastewater is obligatory in order to avoid water pollution. In the present study, performance of Dowex HCR S/S cation exchange resin was evaluated for removal of nickel and zinc from aqueous solutions. Batch shaking adsorption experiments were performed in order to examine the effects of pH, dosage of resin and contact time on removal process. It was observed that more than 98% removal efficiency was achieved under optimal conditions for nickel and zinc. The experimental equilibrium data were tested for the Langmuir, Freundlich and Temkin isotherms. Correlation coefficients indicate the following order to fit isotherms: Langmuir>Freundlich>Temkin for both nickel and zinc ions. Pseudo-first- and -second-order kinetic models were used for describing kinetic data. It was determined that removal of Ni(2+) and Zn(2+) was well-fitted by second-order reaction kinetic. Furthermore, separation factors and distribution coefficients of nickel and zinc for Dowex HCR S/S were calculated.
Asunto(s)
Resinas de Intercambio Iónico/normas , Níquel/aislamiento & purificación , Zinc/aislamiento & purificación , Adsorción , Intercambio Iónico , Cinética , Resinas Sintéticas , SolucionesRESUMEN
In this study, removal of copper (Cu(2+)) and zinc (Zn(2+)) from aqueous solutions is investigated using Cankiri bentonite, a natural clay. During the removal process, batch technique is used, and the effects of pH, clay amount, heavy metal concentration and agitation time on adsorption efficiency are studied. Langmuir, Freundlich and Dubinin-Radushkevich (D-R) isotherms are applied in order to determine the efficiency of natural clay used as an adsorbent. Results show that all isotherms are linear. It is determined that adsorption of Cu(2+) and Zn(2+) is well-fitted by the second order reaction kinetic. In addition, calculated and experimental heavy metal amounts adsorbed by the unit clay mass are too close to each other. It is concluded that natural clay can be used as an effective adsorbent for removing Cu(2+) and Zn(2+) from aqueous solutions.