Adsorption Removal of Dyes from Single and Binary Solutions Using a Cellulose-based Bioadsorbent

Abstract

A high efficiency and eco-friendly porous cellulose-based bioadsorbent was synthesized by grafting acrylic acid and acrylamide to remove anionic dye acid blue 93 (AB93) and cationic dye methylene blue (MB) from single and binary dye solutions. The effects of initial dye concentration, bioadsorbent dosage, contact time, solution pH value, temperature, ionic strength and surfactant content on the adsorption capacity of the bioadsorbent were investigated. The maximum adsorption capacities of the bioadsorbent for both AB93 and MB were 1372 mg g–1 at an initial concentration of 2500 mg L–1. The conditions-dependent adsorption characteristics of the bioadsorbent indicated a high efficiency of dyes removal. The appropriate isotherm model for the equilibrium process was the Freundlich, and the kinetic studies revealed that the adsorption of AB93 and MB followed the pseudo-second-order kinetic models. The adsorbent behaviors were dominated by the electrostatic interactions between the bioadsorbents and the dye molecules. Moreover, the recyclability experiments showed that the bioadsorbent could be reused for at least three cycles with stable adsorption capacity even in complex systems containing binary-dyes, salt, and surfactant. Thus, the cellulose-based bioadsorbent can be effectively used for the removal of dyes from industrial textile wastewater.