采用液晶模板技术,合成了六方中孔氧化硅HMS,通过液相交换技术合成了表面氧化锆官能化的新型材料HMS-Zr,系统研究了其对磷酸盐的吸附行为.XRD、N2吸附/脱附测定表明了HMS-Zr的中孔特性,XPS分析反映其表面形成S—iO—Zr键.HMS-Zr对磷酸盐表现出良好的吸附效率(Zr含量为3.39%,饱和吸附量达到10 P m.gg-1),吸附等温线符合Freund lich吸附模式,低pH条件下可促进磷酸盐吸附.HMS-Zr吸附磷酸盐是吸热的自发过程,吸附动力学显示磷酸盐在HMS-Zr上的吸附符合二级动力学.
In the study,ZrO2 modified hexagonal mesoporous silica(HMS) was prepared and the adsorption of phosphate anion onto the adsorbent was investigated.Structural characterization using XRD,TEM and N2 adsorption/desorption demonstrates that HMS-Zr(10 P mg·g^-1 with Zr content at 3.39%) retains the hexagonal mesoporous structure upon ZrO2 modification.In addition,X-ray photo-electron-spectroscopy results demonstrate the formation of Si—O—Zr on the surface of HMS-Zr.Low pH favors phosphate anion adsorption to HMS-Zr(10 P mg·g^-1) due to the strong attractive electrostatic interaction and the adsorption isotherms are well-described by the Freundlich isotherm model.Phosphate adsorption on HMS-Zr is spontaneous and endothermic in nature and the adsorption process obeys the pseudo second-order kinetics.