REMOVAL OF BASIC DYES FROM WASTEWATER BY USING NATURAL ZEOLITE: KINETIC AND EQUILIBRIUM STUDIES

Özet

Due to their availability and low cost, zeolites have found an important role in adsorption applications. In this study, a natural zeolite, clinoptilolite, was investigated as an adsorbent to remove basic dyes (methylene blue and rhodamine B) from aqueous solution by using batch experiment system. The natural zeolite used in this experiment is mainly composed of clinoptiloite, quartz and heulandite and has cation-exchange capacity of 2.76meq.g-1. Parameters affecting adsorption mechanism such as initial concentration of dyes (50–300mg/l) and contact time (10–325 minutes) on the dye adsorption was examined. From the obtained data it was observed that the natural zeolite presented higher adsorption capacity for methylene blue than rhodamine B with the maximal adsorption capacity of 10.776mg.g-1 and 7.348mg.g-1 at 250C for methylene blue and rhodamine B respectively. The adsorption rate data were analyzed according to pseudo-first-order and pseudo-second-order kinetic models. Kinetic evaluation indicated that the basic dye adsorption on natural clinoptilolite followed the pseudo-second-order model.