F. Widhi Mahatmanti, Harjono, Izzatun Niswah Assa'Idah
Synthesis of superabsorbent polymers based on chitosan modified by acrylic acid and acrylonitrile were conducted. The synthesis was done with a variety of modifiers including chitosan beads; acrylic acid modified chitosan (CTS-AA); acrylonitrile-modified chitosan (CTS-AN); and acrylic acid with acrylonitrile modified chitosan (CTS-AA- AN). The products were characterized with FT-IR and DSC to determine the functional group and its stability to heat treatment and to investigate its swelling ability. FT-IR analysis indicates that in CTS-AA there are functional groups - COOH and -C=C, -CN group in CTS-AN, and -COOH, -C=C, -CN groups in CTS-AA-AN. DSC analysis shows that the superabsorbent polymers are more stable to heating treatment. The swelling test shows that CTS-AA has the highest swelling ability. The superabsorbent polymers are used to reduce the levels of Pb (II) metal ions in solution. This research study pH of the initial metal ion-solution, contact time, and the initial concentration of metal ions. The optimum conditions obtained are pH of chitosan bead 7.5 and pH 4 for CTS-AA, CTS-AN and CTS-AA-AN. The optimum contact time for all the superabsorbent polymers is 45 minutes. The optimum initial concentration for chitosan beads is 16.43 mg/L. While for CTS-AA is 56.75 mg/L, 44.50 mg/L for CTS-AN, and 18.52 mg/L for CTS-AA-AN. © 2020 Author(s).
Chemistry Department, Faculty of Mathematics and Natural Science, Universitas Negeri Semarang, Indonesia
