Preparation, characterization of modified wheat residue and its utilization for the anionic dye removal

The utilization of modified wheat residue (MWR) as sorbent to remove the anionic dye (Reactive Red-24, RR-24) from aqueous solution was studied. MWR was prepared and characterized by specific surface area, SEM, zeta potential, FTIR and elemental analysis. Sorption experiments were carried out as a function of sorbent dosage, pH, contact time and concentration of dye. Results indicated that a mass of amine groups were grafted into the framework of MWR. It was shown that pseudo-second-order kinetic equation could best describe the sorption kinetics. The equilibrium sorption data were well represented by the Langmuir isotherm equation. The maximum sorption capacity of MWR for RR-24 was 200.0 mg/g, which showed higher capacity than those of previous work and a similar capacity compared to those of commercial activated carbon. The results indicated that MWR could be employed as an excellent and low-cost sorbent for removal of anionic dye from aqueous solution.

Research Highlights►Wheat residue is chemically modified into sorbent by amination reaction. ►At room temperature low-cost sorbent bearing amine groups was prepared. ►Modified wheat residue demonstrates excellent sorption capacity for the anionic dye (Reactive Red-24).