School of Environmental Science and Engineering, Shanghai Jiaotong University, Shanghai 200240, China.
J Environ Sci (China). 2011;23(2):199-205. doi: 10.1016/s1001-0742(10)60393-2.
Phosphate removal from aqueous waste streams is an important approach to control the eutrophication downstream bodies of water. A Fe(II) coordinated amino-functionalized silicate adsorbent for phosphate adsorption was synthesized by a post-grafting and metal cation incorporation process. The surface structure of the adsorbent was characterized by X-ray diffraction, N2 adsoropion/desoprotion technique, and Fourier transform infrared spectroscopy. The experimental results showed that the adsorption equilibrium data were well fitted to the Langmuir equation. The maximum adsorption capacity of the modified silicate material was 51.8 mg/g. The kinetic data from the adsorption of phosphate were fitted to pseudo second-order model. The phosphate adsorption was highly pH dependent and the relatively high removal of phosphate fell within the pH range 3.0-6.0. The coexistence of other anions in solutions has an adverse effect on phosphate adsorption; a decrease in adsorption capacity followed the order of exogenous anions: F- > SO4(2-) > NO3- > Cl-. In addition, the adsorbed phosphate could be desorbed by NaOH solutions. This silicate adsorbent with a large adsorption capacity and relatively high selectivity could be utilized for the removal of phosphate from aqueous waste streams or in aquatic environment.
从废水中去除磷酸盐是控制水体富营养化的重要方法。通过后接枝和金属阳离子掺入过程合成了用于磷酸盐吸附的 Fe(II)配位氨基官能化硅酸盐吸附剂。通过 X 射线衍射、N2 吸附/解吸技术和傅里叶变换红外光谱对吸附剂的表面结构进行了表征。实验结果表明，吸附平衡数据很好地符合 Langmuir 方程。改性硅酸盐材料的最大吸附容量为 51.8 mg/g。吸附动力学数据拟合为拟二级模型。磷酸盐的吸附高度依赖于 pH 值，相对较高的磷酸盐去除率在 pH 值 3.0-6.0 范围内。溶液中其他阴离子的共存对磷酸盐的吸附有不利影响；吸附容量的降低遵循外源阴离子的顺序：F- > SO4(2-) > NO3- > Cl-。此外，吸附的磷酸盐可以用 NaOH 溶液解吸。这种具有较大吸附容量和相对较高选择性的硅酸盐吸附剂可用于从废水中去除磷酸盐或在水生态环境中去除磷酸盐。
