Kinetic, thermodynamic and isotherm investigations of Cu2+ and Zn2+ adsorption on Li-Al hydrotalcite-like compound
Kinetic, thermodynamic and isotherm investigations of Cu2+ and Zn2+ adsorption on Li-Al hydrotalcite-like compound
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Li-Al水滑石类化合物吸附Cu2+和Zn2+的动力学、热力学和等温线研究
DOI：
10.1016/j.scitotenv.2020.137120
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发表时间：
2020
影响因子：
9.8
通讯作者：
Zhao Ru-Song
中科院分区：
文献类型：
--
作者：
Zhao Ling-Xi;Liang Ji-Ling;Li Na;Xiao Hua;Chen Li-Zong;Zhao Ru-Song
采用水热法合成了Lisingle bondAl类水滑石（Lisingle bondAl HTlc），并将其用于吸附Cu 2+和Zn 2+，研究其对重金属离子的吸附特性。X射线衍射（XRD）、傅立叶变换红外光谱（FTIR）、扫描电子显微镜（SEM）和透射电子显微镜（TEM）表征结果表明，LiSingle键Al HTlc具有相互连接的花状层状结构。在一定的吸附剂浓度（Cs）下，Cu ~（2+）和Zn ~（2+）在Lisingle键Al HTlc上的吸附动力学和吸附等温线分别符合准二级动力学模型和Langmuir模型。Cs对吸附动力学和吸附等温线的影响可以用Langmuir-表面组分活度（SCA）方程来描述。吸附过程是自发的吸热过程。吸附机理表明吸附过程受两种主要机理控制，即，表面络合和同构取代。这是第一次报告，据我们所知，使用Lisingle键铝HTlc的重金属阳离子Cu ~（2+）和Zn ~（2+）从溶液中的去除。Li单键Al HTlc是一种很有前途的重金属离子水处理吸附剂。
Lisingle bondAl hydrotalcite-like compound (Lisingle bondAl HTlc) was synthesized via a hydrothermal method and used to adsorb Cu2+and Zn2+for investigating the adsorption characteristics of heavy metal cations. The X-Ray diffraction (XRD), fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM) and transmission electron microscopy (TEM) characterizations revealed the interconnecting flower-like layered structure of Lisingle bondAl HTlc. The adsorption kinetics and isotherms of Cu2+and Zn2+on Lisingle bondAl HTlc agreed with the pseudo-second-order model and the Langmuir model at a given sorbent concentration (Cs), respectively. TheCs-effect on the adsorption kinetics and isotherms was observed, and the Langmuir–surface component activity (SCA) equation could be utilized to characterize the effect ofCsin the adsorption isotherms. The adsorption process was spontaneous and endothermic. The adsorption mechanism denoted that the adsorption process was controlled using two main mechanisms, i.e., surface complexation and isomorphic substitution. This is the first report, to the best of our knowledge, on the usage of Lisingle bondAl HTlc for the removal of heavy metal cations Cu2+and Zn2+from a solution. Lisingle bondAl HTlc is a promising sorbent for treating water containing heavy metal cations.