摘要：采用静态吸附实验研究水滑石、沸石、硅藻土对Cr (Ⅵ) 的吸附特性及其差异性;利用扫描电镜 (SEM) 、能谱仪 (EDS) 、红外光谱仪 (FTIR) 分析理化特性及其与吸附特性之间的关系。结果表明:水滑石和硅藻土对于Cr (Ⅵ) 的等温吸附特性符合Freundlich模型, 沸石符合Langmuir模型;水滑石、沸石、硅藻土的最大吸附量qm分别为8.62、12.57、6.32 mg·g^-1, 吸附动力学特性均符合伪二级动力学方程;3种吸附剂均为优惠吸附, 均是自发的、吸热的、无序的;从理化特性来看, 沸石具有最优吸附条件。

关键词：水滑石；沸石；硅藻土；吸附；铬

Abstract：In order to systematically grasp the adsorption properties and the differences of hexavalent chromium on hydrotalcite, zeolite and diatomite, the static adsorption of hexavalent chromium by hydrotalcite, zeolite and diatomite were investigated. The physicochemial properties of the adsorbing materials were characterized by SEM, EDS and FTIR. The results show that the adsorption of hexavalent chromium on hydrotalcite and diatomite fits with Freundlich model. The adsorption on zeolite fits with Langmuir model. According to the Langmuir equation, the maximum adsorption capacity of hydrotalcite, zeolite and diatomite are 8.62, 12.57 and 6.32 mg·g-1, respectively, which are all preferential adsorption. The fitting degree of the three kinds of adsorbents for pseudo-second-orderkinetic is the best. The adsorption of the tree adsorbents is spontaneous, endothermic and disorderly. From the physical and chemical properties, the zeolite has the best adsorption conditions.

Keywords: hydrotalcite；zeolite；diatomite；adsorption；chromium