摘要
近年来,各个行业都产生了大量的重金属废水,已经严重威胁着生态系统和人类健康,因此对制备高效稳定的吸附剂来处理重金属污染的需求逐渐增大.该文以合成出的四硫代钼酸铵及镁铝水滑石为原料,通过离子交换机制,将MoS_(4)^(2-)引入到MgAl-LDH的层状结构中得到MoS_(4)-LDH吸附剂,并将其应用于重金属废水的处理.通过对MoS_(4)-LDH材料的物理与化学性能进行表征,研究了MoS_(4)-LDH的内部结构和吸附机理,发现其通过Cu-S键的形成完成吸附过程.通过对Cu^(2+)进行吸附实验,表明该吸附剂在pH为1~6范围内均有较好的效果,在303 K时吸附量能达到189.14 mg·g^(-1),吸附动力学研究都与准二级模型有很大的相关性,对6种重金属离子进行选择性吸附实验,发现该材料对Pb^(2+)和Cu^(2+)的选择性较好,其选择性顺序为Pb^(2+)>Cu^(2+)>Zn^(2+)>Ni^(2+)>Mn^(2+)>Cd^(2+).因此,MoS_(4)-LDH材料是一种有高吸附量的重金属吸附剂,在实际应用中将会有很好的前景.
The increasing industrial activities in recent years have resulted in a substantial amount of heavy metal-laden wastewater,severely endangering the ecosystem and human health.This has led to a growing demand for the preparation of efficient and stable adsorbents to address heavy metal pollution.In this research,ammonium tetrathiomolybdate and magnesium-aluminum hydrotalcite were selected as the raw materials.By employing the ion-exchange mechanism,MoS_(4)^(2-)was introduced into the layered structure of MgAl-LDH,synthesizing the MoS_(4)-LDH adsorbent.This adsorbent was then applied to the treatment of heavy metal-contaminated wastewater.The physicochemical properties of MoS_(4)-LDH were thoroughly characterized to investigate its internal structure and understand the adsorption mechanism.The findings suggest that the adsorption process is mainly driven by the formation of Cu-S bonds.Adsorption experiments on Cu^(2+)revealed that the adsorbent performs effectively within the pH range of 1~6,achieving an adsorption capacity of up to 189.14 mg·g^(-1)at 303 K.The adsorption kinetics were closely correlated with the pseudo-second-order model.Selective adsorption experiments were conducted on six types of heavy metal ions,and the results showed that the adsorbent has a strong preference for Pb^(2+)and Cu^(2+),with the selectivity order being Pb^(2+)>Cu^(2+)>Zn^(2+)>Ni^(2+)>Mn^(2+)>Cd^(2+).Given its high adsorption capacity,the MoS_(4)-LDH material is expected to have a broad application prospect in the field of heavy metal wastewater treatment.
作者
徐文城
刘四化
周贵寅
XU Wencheng;LIU Sihua;ZHOU Guiyin(School of Life Science and Chemistry,Hunan University of Technology,Zhuzhou 412007,China)
出处
《湘潭大学学报(自然科学版)》
2025年第5期147-157,共11页
Journal of Xiangtan University(Natural Science Edition)
基金
国家自然科学基金面上项目(52070078)
湖南省大学生创新创业训练项目(S202311535098)。
关键词
层状水滑石
重金属吸附
吸附动力学
layered hydrotalcite
heavy metal adsorption
adsorption kinetic
