High performance adsorption of Orange II dye onto modified mussel shell powder

A low-cost and high-efficiency adsorbent was synthesized to remove Orange II dye from wastewater by modifying waste mussel shells with formic acid. The modified mussel shell powder was char-acterized by X-ray powder diffraction, Fourier-transform infrared spectroscopy, scanning electron microscopy, Brunauer–Emmett–Teller surface area determination, and X-ray photoelectron spectros-copy. The effects of solution pH, contact time and temperature on the adsorption of Orange II dye by modified mussel shell powder were investigated. The adsorption capacity of modified mussel powder to Orange II decreased with the pH value increased from 3 to 11. The adsorption capacity gradually increased with contact time, and reached the maximum in about 18 min. The pseudo-first-order kinetic model can fit the adsorption behavior well. Thermodynamic results show that the adsorption process is spontaneous and endothermic. The maximum adsorption capacity of modified mussel shell for Orange II dye was determined to be 65.43 mg/g, which is much higher than the previously reported results. The results showed that modified mussel shell powder had a potential application prospect as an adsorbent for the removal of Orange II from waste water.