Abstract
In this study, the mesoporous carbon (CMK-3) was successfully synthesized using mesoporous silica (SBA-15) prepared from gold mine tailings (CGMT) for removal of anionic dye from aqueous solution. For comparison, CMK-3 was prepared by the same method from pure silica (CT), and the other CMK-3 sample was prepared by a one-pot route mixing Pluronic P123 (CP). The effect of the carbonization time on the synthesis of all CMK-3 samples was investigated, and the samples were characterized by X-ray diffraction (XRD) and N2-adsorption/desorption. The one with the highest surface area was chosen as an adsorbent for each CMK-3 obtained from different methods. Batch adsorption experiments were studied to determine the influence of pH, contact time, and initial dye concentration. The adsorption kinetic obeyed the pseudo-second-order model. All carbon-based adsorbents were observed to be quite effective for the removal of dye with adsorption percentage in the order of CP > CT > CGMT. The maximum adsorption capacities were 188.99 and 204.57 mg·g−1 for CGMT and CT, respectively. The comparative results of all carbon-based adsorbents show that CGMT can be applied as a low-cost alternative to CT for dye removal.
Equilibrium Isotherm, Kinetic, and Thermodynamic Studies of Divalent Cation Adsorption onto Calamus gracilis Sawdust-Based Activated Carbon