Adsorption of basic and acid dyes using alginate/sericin composite beads

Abstract

Alginate/sericin composite beads were prepared from a blend between sericin and alginate by the gelation process. The composite beads were used as the adsorbent for the removal of basic and acid dyes from an aqueous solution. The morphological structure of the beads was characterized by scanning electron microscopy (SEM). Adsorption experiments were conducted using contact time, concentration of sericin, pH and adsorbent dosage. The equilibrium adsorption data was achieved within 360 min at 5 % w/v of sericin. The Langmuir isotherm model showed the maximum monolayer adsorption capacity for basic dye (pH 8) and acid dye (pH 2) was 5.98 and 7.60 mg/g, respectively. The adsorption kinetics were described by the pseudo second-order model. The desorption experiment was demonstrated and repeated three times, all of which exhibited that it was regenerative and reusable. This study demonstrates that the alginate/sericin composite beads are effective adsorbent for the removal of dyes from aqueous solution. © 2018 Chemical Publishing Co. All Rights Reserved.