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采用浸溃法制备了碳纳米管负载镍镧(Ni-La)/镍钴(Ni-Co)双金属复合材料Ni-La/CNT_s和Ni-Co/CNTs,采用投射电子显微镜(TEM)和X射线粉末衍射仪(XRD)对样品的结构特征和组成进行了表征。并通过吸附实验探讨了Ni-La/CNTs和Ni-Co/CNTs对水中2,2’,4,4’.四溴联苯醚(BDE-47)的去除性能和去除机制。结果表明:Ni-La/CNTs和Ni-Co/CNTs表面负载了Ni-La或Ni-Co双金属粒子,主要是金属氧化物,并没有检测到明显的金属单质信号。Ni-La/CNTs和Ni-Co/CNTs对BDE-47均具有良好的去除性能;增大BDE-47的初始浓度,2种材料对BDE-47的吸附速率减小,而吸附量增大。准二级动力学方程能够较好的拟合BDE-47在Ni-La/CNTs和Ni-Co/CNTs上的吸附动力学过程,吸附速率常数大小顺序为:k_(CNTs)>K_(Ni-La/CNTs)>K_(Ni-Co/CNTs。CNTs对BDE-47的去除机制是吸附作用;而Ni-La/CNTs和Ni-Co/CNTs2种双金属复合材料对BDE.47的去除过程中,除了吸附作用占主要作用外,同时还存在一定的降解作用。Ni-La/CNTs和Ni-Co/CNTs重复使用4次后,对水中BDE-47的去除率仍超过80%,表明2种复合材料具有较好的重复使用性能。
Ni-La / Ni-Co bimetal composites Ni-La / CNT_s and Ni-Co / CNTs supported on carbon nanotubes were prepared by impregnation method. The structures of the composites were characterized by transmission electron microscopy (TEM) The structure and composition of the samples were characterized by X-ray powder diffraction (XRD). The removal performance and removal mechanism of 2,2 ’, 4,4’-tetrabromodiphenyl ether (BDE-47) in water by Ni-La / CNTs and Ni-Co / CNTs were investigated by adsorption experiments. The results show that Ni-La or Ni-Co bimetallic particles, mainly metal oxides, are supported on the surface of Ni-La / CNTs and Ni-Co / CNTs and no obvious single element signal is detected. Both Ni-La / CNTs and Ni-Co / CNTs exhibited good removal performance for BDE-47. When the initial concentration of BDE-47 was increased, the adsorption rate of BDE-47 decreased and the adsorption capacity increased. The quasi-second-order kinetic equation can well fit the adsorption kinetics of BDE-47 on Ni-La / CNTs and Ni-Co / CNTs. The adsorption rate constants are as follows: k CNTs> K Ni- La / CNTs)> K_ (Ni-Co / CNTs.CNTs) on the removal mechanism of BDE-47 is adsorption; while the bimetallic composites of Ni-La / CNTs and Ni-Co / , Except for the main role of adsorption, but also some degradation.Ni-La / CNTs and Ni-Co / CNTs repeated use of four times, the removal of BDE-47 in water is still more than 80%, indicating that two kinds Composite materials have better reusability.