煅烧 MgAl-CO3 层状双氢氧化物去除水中的高氯酸盐。

Removal of perchlorate in water by calcined MgAl-CO3 layered double hydroxides.

机构信息

State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, Shanghai 200092, China.

出版信息

Water Environ Res. 2013 Apr;85(4):331-9. doi: 10.2175/106143013x13596524516103.

Abstract

Perchlorate is widely known as an inorganic endocrine disruptor. In this study, MgAl-CO3 layered double hydroxides with different Mg/Al molar ratios were prepared using a coprecipitation method and followed by a calcination process at a temperature range of 300 to 700 degrees C. Results showed that the best synthesis conditions were a calcination temperature of 550 degrees C and Mg/Al molar ratio of 3. Further, the adsorbent and its adsorption product were characterized by x-ray diffraction, Fourier transform-infrared spectroscopy, and thermogravimetric-differential thermal analysis. The layered double hydroxides structures in the adsorbent were lost during calcination at 550 degrees C but were reconstructed subsequent to adsorption of perchlorate, indicating that the "memory effect" appeared to play an important role in perchlorate adsorption. The perchlorate adsorption pattern was best described by the pseudo-second-order kinetics model, while the Freundlich isotherms appropriately explained perchlorate adsorption data.

摘要

高氯酸盐是一种广为人知的无机内分泌干扰物。在本研究中，采用共沉淀法制备了不同 Mg/Al 摩尔比的 MgAl-CO3 层状双氢氧化物，然后在 300 至 700°C 的温度范围内进行煅烧。结果表明，最佳的合成条件是煅烧温度为 550°C，Mg/Al 摩尔比为 3。进一步，通过 X 射线衍射、傅里叶变换红外光谱和热重-差热分析对吸附剂及其吸附产物进行了表征。在 550°C 煅烧时，吸附剂中的层状双氢氧化物结构丢失，但在吸附高氯酸盐后被重建，表明“记忆效应”似乎在高氯酸盐吸附中起着重要作用。准二级动力学模型很好地描述了高氯酸盐的吸附模式，而 Freundlich 等温线则很好地解释了高氯酸盐的吸附数据。