Facile synthesis of graft copolymers of maltodextrin and chitosan with 2-acrylamido-2-methyl-1-propanesulfonic acid for efficient removal of Ni(II), Fe(III), and Cd(II) ions from aqueous media

Abstract

In this paper, graft copolymers of maltodextrin or chitosan with 2-acrylamido-2-methyl-1-propanesulfonic acid were synthesized and labeled P1 or P2, respectively. Also, homopolymer of 2-acrylamido-2-methyl-1-propanesulfonic acid was synthesized and labeled P3. The synthesized polymers were characterized using different tools such as CHNS elemental analysis, FT-IR, and UV-Vis spectrophotometer. The synthesized polymers were used as adsorbents for the removal of Ni(II), Fe(III), and Cd(II) ions from aqueous media. Contact time, pH, concentration of metal ions, and amount of polymers were studied. The adsorption of Ni(II) ions using P1, P2, or P3 samples follows the pseudo-first-order. Also, the adsorption of Fe(III) ions using P1 or P2 samples follows the pseudo-second-order. In addition, the adsorption of Fe(III) ions using P3 sample follows the pseudo-first-order. Besides, the adsorption of Cd(II) ions using P1 or P3 samples follows the pseudo-first-order. Moreover, the adsorption of Cd(II) ions using P2 sample follows the pseudo-second-order. The adsorption of Ni(II), Fe(III), or Cd(II) ions using P1, P2, or P3 samples follows the Langmuir isotherm. Qm of P1, P2, and P3 toward Ni(II) ions equals 26.66, 32.74, and 27.33 mg g−1, respectively. Also, Qm of P1, P2, and P3 toward Fe(III) ions equals 29.31, 28.97, and 29.01 mg g−1, respectively. In addition, Qm of P1, P2, and P3 toward Cd(II) ions equals 27.46, 34.81, and 35.59 mg g−1, respectively.