摘要
采用共沉淀法将番石榴树叶(guava leaf,Gl)和镁铝类水滑石(MgAl-layered double hydroxide,MgAl-LDH)复合得到一种环保的新型复合吸附剂Gl/MgAl-LDH,并将其用于吸附溶液中的镉(cadmium,Cd)。通过吸附动力学、等温吸附探究了Gl/MgAl-LDH对Cd^(2+)的吸附性能,并使用各种表征手段探究了材料的理化性质及吸附机理。结果表明,Gl/MgAl-LDH在60 min时即可达到吸附平衡,吸附量为37.50 mg·g^(-1),高于MgAl-LDH和Gl。Gl/MgAl-LDH对Cd^(2+)的吸附过程符合拟二级动力学模型及Freundlich模型,最大吸附量为68.43 mg·g^(-1)。表征结果表明LDH通过金属离子与Gl上的有机官能团发生络合反应,成功构筑到Gl表面。Gl/MgAl-LDH吸附后的XPS图谱中出现了Cd元素的谱峰,证实了Cd^(2+)被有效吸附到材料表面。Gl/MgAl-LDH去除Cd^(2+)的主要机理为吸附沉淀和有机络合。以上研究结果可为生物质作为吸附剂的资源化利用提供参考。
An environmentally friendly and novel composite adsorbent,Gl/MgAl-LDH,was obtained by Guava leaf(Gl)and MgAl-Layered double hydroxide(MgAl-LDH)composite with a co-precipitation method,and Gl/MgAl-LDH was used to adsorb cadmium(Cd)in solution.The adsorption performance of Gl/MgAl-LDH towards Cd^(2+)was investigated by adsorption kinetics and isotherm,its properties and adsorption mechanism were studied by different characterization instruments.The experimental results showed that Gl/MgAl-LDH could reach the adsorption equilibrium at 60 min,and the adsorption amount was 37.50 mg·g^(−1),which was higher than that of MgAl-LDH or Gl.Adsorption process of Cd^(2+)onto Gl/MgAl-LDH conformed to the proposed secondary kinetic and Freundlich models with a maximum adsorption amount of 68.43 mg·g^(−1).Characterization results showed that the complex reaction occurred between metal ions on LDH and organic functional groups on Gl,and LAD was successfully anchored on Gl surface.The appearance of the spectral peaks of elemental Cd in the XPS spectra of the adsorbed Gl/MgAl-LDH confirmed the effective adsorption of Cd^(2+)onto the material.The main mechanisms of Cd^(2+)removal by Gl/MgAl-LDH were adsorption precipitation and organic complexation.The results of this study provide a reference for the resource utilization of biomass as an adsorbent.
作者
朱玉祺
尹涓涓
钟凯
卢定添
顾心怡
张超兰
ZHU Yuqi;YIN Juanjuan;ZHONG Kai;LU Dingtian;GU Xinyi;ZHANG Chaolan(School of Resources,Environment and Materials,Guangxi University,Nanning 530004,China;College of Agriculture,Guangxi University,Nanning 530004,China)
出处
《环境工程学报》
CAS
CSCD
北大核心
2024年第6期1541-1549,共9页
Chinese Journal of Environmental Engineering
基金
国家自然科学基金资助项目(U22A20590)。
