硅藻土-环糊精杂化材料的制备与吸附性能

Preparation and adsorption properties of diatomite-cyclodextrin hybrid materials

以硅藻土和β-环糊精(β-CD)作为原料,通过乳液聚合方法在提纯后的硅藻土表面聚合β-CD,制备硅藻土/β-CD有机无机杂化材料。采用傅里叶红外变换光谱、X射线衍射光谱、扫描电子显微镜对化学结构、结晶性能以及微观表面形貌进行表征;研究了杂化材料在吸附Cu2+过程中吸附机理以及吸附的影响因素。FT-IR图显示杂化材料中出现硅藻土以及β-CD的主要基团峰值;XRD图显示杂化材料结晶峰包含硅藻土和β-CD的结晶峰;杂化材料为完整微球,结构完整。杂化材料吸附过程符合拟二阶动力学方程、Langmuir等温线模型,理论最大吸附容量为145.1778 mg/g。吸附最佳条件为接触时间50 min,pH为7,温度20℃;在此条件下杂化材料的去除率为64.747%,比硅藻土提升20.3%,比β-CD提升21.3%,吸附效果良好。

The diatomite/β-CD organic-inorganic hybrid materials were prepared by graftingβ-CD on the surface of purified diatomite via emulsification polymerization method using diatomite andβ-cyclodextrin(β-CD)as raw materials.The chemical structures,crystallization properties and microscopic surface morphologies were characterized by FT-IR,XRD and SEM.The adsorption mechanism and effects of hybrid materials to Cu2+were studied.The results of FT-IR spectra confirmed the present of main group in diatomite andβ-CD hybrid materials.XRD patterns showed that the crystallization peaks of the hybrid materials contained diatomite andβ-CD crystallization peaks.The hybrid materials were spherical microspheres.The adsorption of hybrid materials fitted the quasi-second-order kinetic equation and the Langmuir isotherm model.The theoretical maximum adsorption ability was 145.1778 mg/g and the optimal conditions were 50 min of contact time,pH 7 and 20℃.Under these conditions,the removal rate of hybrid materials was 64.747%,which increased by 20.3%and 21.3%in comparison with diatomite andβ-CD.