Enhanced Enhanced adsorption of U(VI) and 241Am(III) from wastewater using Ca/Al layered double hydroxide@carbon nanotube composites
Enhanced Enhanced adsorption of U(VI) and 241Am(III) from wastewater using Ca/Al layered double hydroxide@carbon nanotube composites
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Ca/Al层状双氢氧化物@碳纳米管复合材料增强对废水中U(VI)和Am-241(III)的吸附
DOI：
10.1016/j.jhazmat.2017.12.062
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发表时间：
2018-04-05
影响因子：
13.6
通讯作者：
Wang, Xiangke
中科院分区：
文献类型：
--
作者：
Chen, Haijun;Chen, Zhe;Wang, Xiangke
采用共沉淀法和水热老化法制备了Ca/Al层状双氢氧化物修饰碳纳米管（Ca/Al-LDH@CNTs）复合材料。通过SEM、TEM、EDS、XRD、FT-IR、UV-vis和XPS等技术对所制备的Ca/Al-LDH@CNTs进行了表征，并将其应用于各种环境条件下（即，pH、离子强度、温度和接触时间）。结果表明，Ca/Al-LDH@CNTs对U（VI）的吸附量是裸CNTs的4倍。动力学研究反映了U（VI）在Ca/Al-LDH@CNTs上的化学吸附是通过含氧官能团进行的。吸附等温线表明，U（VI）在Ca/Al-LDH@CNTs上的吸附符合Langmuir吸附模型，在289.15 K时，Ca/Al-LDH@CNTs对U（VI）的最大吸附量为382.9 mg g（-1）。由吸附等温线计算的热力学参数表明，U（VI）在Ca/Al-LDH@CNTs上的吸附是吸热的自发过程。在pH = 8.0时，Ca/Al-LDH@CNTs对Am-241（III）的去除率接近91%，表明Ca/Al-LDH@CNTs是一种很有前途的低放射性污染修复材料。(C)2017爱思唯尔B. V.保留所有权利。
Ca/Al layered double hydroxide decorated carbon nanotube (Ca/Al-LDH@CNTs) composites were fabricated by co-precipitation method and hydrothermal aged treatment. The prepared Ca/Al-LDH@CNTs was characterized by SEM, TEM, EDS, XRD, FT-IR, UV-vis and XPS techniques, and applied to remove U(VI) from aqueous solutions under various environmental conditions (i.e., pH, ionic strength, temperature and contact time). The results indicated that the adsorption of U(VI) on Ca/Al-LDH@CNTs was four times higher than that of U(VI) on bare CNTs. The kinetic investigations reflected the chemisorption of U(VI) on Ca/Al-LDH@CNTs through oxygen-containing functional groups. The adsorption isotherms demonstrated that the adsorption of U(VI) was well fitted by Langmuir model and the maximum adsorption capacity of U(VI) on Ca/Al-LDH@CNTs was calculated to be 382.9 mg g(-1) at 289.15 K. The thermodynamic parameters calculated from temperature-dependent isotherms suggested that U(VI) adsorption on Ca/Al-LDH@CNTs were endothermic and spontaneous process. Furthermore, Ca/Al-LDH@CNTs could remove similar to 91% of Am-241(III) at pH = 8.0, which confirmed Ca/Al-LDH@CNTs as a promising material for multiply low level radionuclides' pollution remediation. (C) 2017 Elsevier B.V. All rights reserved.