School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou, 215009, China.
Jiangsu Key Laboratory for Environment Functional Materials, School of Materials Science and Engineering, Suzhou University of Science and Technology, Suzhou, 215009, China.
Environ Sci Pollut Res Int. 2023 Jul;30(34):82217-82229. doi: 10.1007/s11356-023-28226-0. Epub 2023 Jun 15.
Removal of phosphate from water is very crucial for protecting the ecological environment since massive phosphorus fertilizers have 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 approaches including X-ray diffraction (XRD), N physisorption, thermogravimetric mass spectrometry (TG-MS), X-ray photoelectron spectroscopy (XPS), and Fourier transform infrared (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 (rCa:Si) improved the phosphate removal capacity of CaAS nanocomposites, especially CaAS with the optimum synthesis molar ratio of Ca:Si as 0.55 showed the high adsorption capacity of 92.0 mg·g to high concentration of phosphate (> 200 mg·L). Note that the CaAS-0.55 had a fast exponentially increased adsorption capacity with increasing the phosphate concentration and correspondingly showed a much faster phosphate removal rate than pristine CaCO. Apparently, mesoporous structure of SBA-15 contributed to high disperse of CaCO nanoparticles leading to the monolayer chemical adsorption complexation formation of phosphate calcium (i.e., =SPOCa, =CaHPO, and =CaPOCa). Therefore, mesoporous CaAS-0.55 nanocomposite is an environmental-friendly adsorbent for effective removal of high concentration of phosphate in neutral contaminated wastewater.
从保护生态环境的角度来看，去除水中的磷酸盐非常重要，因为大量的磷肥被广泛使用，导致了严重的水质恶化。因此，我们通过简单的湿浸渍法制备了一系列不同 Ca:Si 摩尔比（CaAS-x）的负载碳酸钙的介孔 SBA-15 纳米复合材料作为磷吸附剂。采用 X 射线衍射（XRD）、N 物理吸附、热重质谱（TG-MS）、X 射线光电子能谱（XPS）和傅里叶变换红外（FT-IR）等多种方法对介孔 CaAS-x 纳米复合材料的结构、形貌和组成进行了表征。通过吸附和解吸批试验研究了 CaAS-x 纳米复合材料的磷酸盐吸附效率。结果表明，Ca:Si 摩尔比（rCa:Si）的增加提高了 CaAS 纳米复合材料的磷酸盐去除能力，特别是合成摩尔比 Ca:Si 为 0.55 的 CaAS 表现出 92.0 mg·g 的高吸附容量，对高浓度的磷酸盐（>200 mg·L）具有高去除能力。值得注意的是，CaAS-0.55 具有快速指数增加的吸附容量，随着磷酸盐浓度的增加，相应地比原始 CaCO 具有更快的磷酸盐去除率。显然，SBA-15 的介孔结构有助于 CaCO 纳米粒子的高分散，从而形成磷酸钙的单层化学吸附络合物（即，=SPOCa、=CaHPO 和 =CaPOCa）。因此，介孔 CaAS-0.55 纳米复合材料是一种环境友好的吸附剂，可有效去除中性污染废水中的高浓度磷酸盐。
