勃姆石
吸附
水溶液
吸附
无机化学
选择性
水热合成
硝酸
材料科学
比表面积
热液循环
核化学
化学
化学工程
催化作用
有机化学
冶金
铝
工程类
作者
Jiacheng Li,Miao Li,Yang Xu,Yu Zhang,Xiang Liu,Fang Liu,Fanbin Meng
出处
期刊:Nanotechnology
[IOP Publishing]
日期:2019-02-22
卷期号:30 (19): 195702-195702
被引量:10
标识
DOI:10.1088/1361-6528/aaff21
摘要
Boehmite with different morphologies was synthesized using a simple hydrothermal method for the removal of Cr(VI) and nitrates from polluted water. When the pH of the hydrothermal system was changed, the final crystallization products had morphologies of one-dimensional rods or two-dimensional sheets with different sizes. The boehmites were characterized and used for the adsorption of aqueous Cr(VI) and nitrates. Their bulk structure and surface properties significantly changed with the corresponding morphology, which prominently affected their adsorption capacity. Boehmite with a 2D small sheet-like structure showed the highest adsorption capacity (64.7 mg g-1). Moreover, the small sheet-like boehmite showed a remarkable adsorption capacity towards nitrates (74.5-378.5 mg g-1) and maintained a high selectivity to Cr(VI) in the presence of competing anions such as NO3-, [Formula: see text] and Cl-. The isotherms for Cr(VI) sorption could be better explained using the Langmuir model, indicating a monolayer adsorption of the Cr species, while the isotherms for nitrate sorption followed the Freundlich model, suggesting a multilayer adsorption. The active adsorption sites of boehmite were found to be the Lewis acid sites and surface hydroxyl groups according to the outcomes of the analysis using a series of characterization methods such as IR, Raman and x-ray photoelectron spectra. The unique structure of boehmite is beneficial to adsorb anion containments while maintaining a high selectivity to Cr(VI) species. Because of the multiple Lewis or Brönsted acid sites in boehmite, the Cr(VI) was reduced to less toxic Cr(III) species and immobilized on the surface of boehmite. In consideration of the low-cost and good regeneration capacity, the small sheet-like boehmite would be useful for the removal of anions present in polluted water.
科研通智能强力驱动
Strongly Powered by AbleSci AI