Dyes are an important class of pollutants. Among various removal methods, adsorption occupies a prominent place in dye removal [1]. The aim of this study is to use a cheap sorbent such as beet residue and its modification for the fast and efficient removal of the dye, reactive black 5 (RB5), from aqueous solutions. For this purpose, a series of experiments were performed. The beet residue was modified by epichlorohydrin in the presence of pyridine. Epichlorohydrin attached to the cellulose in alkaline conditions has been demonstrated to be the most likely sites for the attachment of bioactive agents such as amines and imines groups [2]. The kinetic and thermodynamic studies were carried out for the adsorption of RB5 from aqueous solutions onto beet residue and modified beet residue in batch experiments. The removal of this dye was examined by varying experimental conditions such as the amount of sorbent, contact time, concentration, and temperature. It was found that more than 90% of dye was removed in a short time from the solution. The experimental data were applied to four sorption models such as Langmuir, Freundlich, Temkin, and Redlich-Peterson [3, 4]. The Langmuir model was fitted properly with high-correlation coefficients in the applied range of initial concentrations in comparison with other sorption models. The results indicate that the adsorption of RB5 in the presence of modified beet residue was greater than beet residue.

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