Experimental study of the removal of copper ions using hydrogels of xanthan, 2 acrylamido 2 methyl 1 propane sulfonic acid, montmorillonite: Kinetic and equilibrium study.
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 Cu(2+=321.8 mg/L, Temperature=45 degC, 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 DGdeg values and the positive DSdeg confirmed that the adsorption was a spontaneous process. The positive DHdeg values suggested that the adsorption was endothermic in nature.
Carbohydrate polymers