Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1383308 | Carbohydrate Polymers | 2016 | 9 Pages |
•The usage of XG polysaccharide and AMPS monomer as novel hydrogel composites.•Incorporation of MMT within the hydrogel matrix and effect of it on the adsorption.•Characterization of XG, XG-g-P(AMPS) and XG-g-P(AMPS)/MMT hydrogels.•Adsorption isotherm, adsorption kinetics and thermodynamic parameters were studied.
In this paper, removal of copper ions from aqueous solution using novel xanthan gum (XG) hydrogel, xanthan gum-graft-2-acrylamido-2-methyl-1-propane sulfonic acid (XG-g-P(AMPS)) hydrogel and xanthan gum-graft-2-acrylamido-2-methyl-1-propane sulfonic acid/montmorillonite (XG-g-P(AMPS)/MMT) hydrogel composite were studied. The structure and morphologies of the xanthan-based hydrogels were characterized by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscope (SEM). Adsorbents comprised a porous crosslink structure with side chains that carried carboxyl, hydroxyl and sulfonate. Maximum adsorption was observed in the pH = 5.2, initial concentrations of Cu2+ = 321.8 mg/L, Temperature = 45 °C, contact time = 5 h with 0.2 g/50 mL of the hydrogels. Adsorption process was found to follow Langmuir isotherm model with maximum adsorption capacity of 24.57, 39.06 and 29.49 mg/g for the XG, XG-g-P(AMPS) and XG-g-P(AMPS)/MMT, respectively. Adsorption kinetics data fitted well with pseudo second order model. The negative ΔG° values and the positive ΔS° confirmed that the adsorption was a spontaneous process. The positive ΔH° values suggested that the adsorption was endothermic in nature.