Synthesis of Calcium Carbonate Loaded Mesoporous SBA-15 Nanocomposites for Removal of Phosphate from Solution

Removal of phosphate from water is very crucial for protecting the ecological environment since massive phosphorus fertilizers has been widely used and caused serious water deterioration. Thus, we fabricated a series of calcium carbonate loaded mesoporous SBA-15 nanocomposites with different Ca:Si molar ratio (CaAS- x ) as phosphorus adsorbents via a simple wet-impregnation method. The multiply approach including XRD, N 2 physisorption, TG-MS and FT-IR were used to characterize the structure, morphology and composition of mesoporous CaAS- x nanocomposites. The phosphate adsorption efficiency of the CaAS- x nanocomposites was studied through adsorption and desorption batch tests. Results showed that the increases of Ca:Si molar ratio ( r Ca:Si) favored the phosphate removal efficiency of CaAS nanocomposites, especially CaAS with the optimum molar ratio of Ca:Si as 0.55 showed the high adsorption capacity of 92.0 mg·g -1 to high concentration of phosphate (> 200 mg l -1 ). Note that the adsorption capacity of the CaAS- x exponentially fast grew up with increasing the phosphate concentration. Apparently, mesoporous structure of SBA-15 contributed to high disperse of CaCO 3 nanoparticles leading to the multiplayer formation and fast growth of phosphate calcium precipitation. Therefore, mesoporous CaAS-0.55 nanocomposite is an environmental-friendly adsorbent for effective removal of high concentration of phosphate in neutral contaminated wastewater.