期刊
WATER AIR AND SOIL POLLUTION
卷 227, 期 10, 页码 -出版社
SPRINGER INT PUBL AG
DOI: 10.1007/s11270-016-3079-5
关键词
Layered double hydroxide; Calcined layered double hydroxide; Fluoride; Adsorption; Column system; Groundwater
资金
- Swiss Federal Institute of Aquatic Science and Technology (Eawag)
- Spanish Government, MINECO [MAT2012-31127]
In this study, batch experiments have been carried out to investigate the mechanism of fluoride uptake by layered double hydroxide (LDH) and calcined layered double hydroxide (CLDH). Furthermore, practical use of these synthetic minerals was studied in continuous mini-column experiments. In these column studies, groundwater from Ethiopia was tested. LDH and CLDH were synthesized with Mg/Al mole ratio of 2. From batch experimental study, LDH and CLDH have shown maximum removal capacity of 84 and 222 mg F-/g from aqueous solution, respectively. It was observed that fluoride removal was pH dependent with favorable pH range of 5-7 (max. at pH 6). The mechanism of removal is suggested to be ion exchange for LDH and a memory effect followed by surface precipitation reaction for CLDH. The presence of other anions lowered defluoridation capacity of LDH in the order of PO43- > SO42- > NO3- approximate to Cl-. From continuous experiments at 1 mM NaHCO3, LDH showed maximum defluoridation capacity of 1.3 mg/g and CLDH up to 20 mg/g. It was also observed that increase of bicarbonate concentration to 10 mM lowered the fluoride uptake capacity of CLDH to 4 mg/g. The presence of 1 mM H4SiO4 further reduced fluoride uptake capacity to 3 mg/g. CLDH column tested with groundwater from the Rift Valley with 10.5 mg F-/L has shown maximum removal capacity of 2.2 mg F-/g. Regeneration of this column indicated that CLDH has a good potential to be re-used.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据