REACTIVE RED 3 AND DIRECT BROWN 95 DYES ADSORPTION ONTO CHITOSAN

The chitosan availability in adsorption of C.I. Reactive Red 3-18159 (RR-3) and C.I. Direct Brown 95-30145 (DB-95) dyes from aqueous solutions was investigated by using the batch method. Experiments were carried out as a function of contact time, dye concentrations and temperature. The influence of pH and sodium chloride concentration were also investigated. The adsorption parameters were determined based on Langmuir and Freundlich isotherms obtained from the equilibrium adsorption data for the reactive dye and for the direct dye, while the kinetic and thermodynamic parameters were used to establish the adsorption mechanism. As an adsorbent, chitosan was found to prefer the RR-3 dye, retaining up to 151.52 mg textile dye per gram at 20 degrees C, whereas a retention of only 41.84 mg textile dye per gram at 50 degrees C has been achieved for DB-95 dye.