摘要
采用水热法合成了不同铁掺杂量的Mg/Al/Fe型类水滑石(MAF),根据X射线衍射(XRD)的测定结果,铁存在一个最佳投加量,铁的掺杂量过大则会导致水滑石的层状结构被破坏。通过扫描电镜(SEM)和比表面分析仪(BET)研究了MAF焙烧后的复合金属氧化物(CMAF)的结构和性能,并考察了CMAF对水中氟离子的吸附性能。与CMA相比(铁掺杂量为零),CMAF对氟离子的吸附去除效率明显提高(最大吸附容量75.2 mg/g),整个吸附过程可以用Langmuir吸附等温线更好地描述。通过XRD测定和晶格参数计算,CMAF的结构由吸附前的复合氧化物恢复到层状水滑石结构,表明氟离子在水滑石重构过程中作为层间阴离子进入到水滑石内部,从而达到较高的除氟效率。
In this study, Mg/Al/Fe hydrotalcites （MAF） with different iron content were prepared by hydrothermal method. Based on the characterization of XRD, there existed a suitable iron ratio and the layer structure would be destroyed with excessive iron. The morphology and property of the mixed oxides derived from MAF （CMAF） were characterized by SEM and BET. The adsorption of fluoride on CMAF was also investigated. In comparison with CMA （iron content was 0） , CMAF exhibited a higher efficiency toward fluoride removal （the maximum adsorption capacity is 75.2 mg/g）. Langmuir isotherm was found more suitable to describe the adsorption process. Moreover, the structure of CMAF shifted to layer structure after fluoride adsorption. The result indicates that fluoride has intercalated the layer structure of hydrotalcite, leading to higher efficiency of fluoride removal.
出处
《环境工程学报》
CAS
CSCD
北大核心
2010年第1期110-114,共5页
Chinese Journal of Environmental Engineering
关键词
水滑石
氟离子
吸附
重整
hydrotalcite
fluoride
adsorption
reconstruction
