Adsorption removal of eriochrome black t (Ebt) and rose bengal (rb) from aqueous solutions using bio-sorbents combination

Abstract

Adsorption of eriochrome black T (EBT) and rose bengal (RB) mixture from aqueous solutions was investigated using a mixture of low-cost biosorbents – 50% of raw state potato peels and 50% of raw state eggshell (M 50%). The surface charge distribution was determined by acid-base titration and the point of zero charge of the M 50% was found to be 8.5. The adsorbent materials were characterized by Fourier transform infrared spectroscopy and X-ray diffraction. It was confirmed that M 50% was mainly composed of calcite and cellulose. The effect of various operating parameters such as contact time, pH, temperature, etc., was studied. The amount of the adsorption decreased when solution pH increased. The pseudo-second order kinetic model provided the best fit to the experimental data for the adsorption of EBT and RB. The obtained thermodynamic parameters indicate that the adsorption process is endothermic one. According to the obtained results, the new biosorbent may be recommended as an industrial adsorbent for the treatment of effluents containing EBT and RB.