麦秸秆负载纳米水合氧化铁去除水中Cu2+的特性研究
Study on characteristics of wheat straw loaded with nano-hydrated iron oxide for removing Cu2+from water
陈权 1陈一良 1宋文旭 1张磊 1王铮 1阮宏华1
作者信息
- 1. 南京林业大学生态与环境学院,江苏 南京 210037
- 折叠
摘要
将秸秆资源化利用与废水处理相结合,通过温和简便的浸渍法将水合氧化铁(HFO)纳米颗粒稳定地负载在麦秸秆表面制得二维片状纳米复合吸附剂(记为WS-HFO)用于去除水中的重金属Cu2+,并探究了 WS-HFO对Cu2+的吸附性能及机理.扫描电镜(SEM)观测到麦秸秆微观形貌有明显变化,负载的HFO纳米颗粒直径为50～80 nm,通过氮气吸附/脱附曲线确定了材料的比表面积和孔径分布.投加量实验中0.07 g的WS-HFO对50 mL 16 mg/L Cu2+的去除率接近100％.溶液pH对WS-HFO吸附Cu2+有较大影响,pH为5.9时吸附量最大;竞争吸附实验证明共存阳离子Na+、Mg2+、Ca2+浓度高时不利于Cu2+的吸附.WS-HFO对Cu2+的吸附动力学符合准二级动力学方程,吸附等温线符合Langmuir模型,WS-HFO对低浓度Cu2+有很强的吸附亲和力.固定床柱吸附/脱附运行结果表明,1.8 g的WS-HF O能有效处理1 980 mL模拟废水,使得出水平均Cu2+低于0.05 mg/L.以4 mol/L NaCl为脱附剂,7次循环重复利用试验Cu2+去除率能保持在89％～100％.
Abstract
In this study,nanocomposite materials were developed combining straw resource utilization with wastewater treatment.The two-dimensional sheet nanocomposite adsorbent WS-HFO was prepared by stable loading of hydrated iron oxide(HFO)nanoparticles on the surface of wheat straw through a mild and simple impregnation method for the removal of heavy metal Cu2+in water.The adsorption performance and mechanism of WS-HFO for Cu2+were also explored.SEM characterization revealed significant changes in the microstructure of wheat straw,and the diameter of loaded HFO nanoparticles was 50-80 nm.Specific surface area and pore size distribution of the materials were determined by N2 adsorption/desorption curves.In the dosing experiments,removal rate of 50 mL 16 mg/L Cu2 by 0.07 g WS-HFO was almost 100％.Solution pH had a great influence on the Cu2+adsorption onto WS-HFO,and the adsorption capacity was maximum at pH 5.9.Competitive adsorption experiments proved that high concentrations of coexisting cations Na+,Mg2+and Ca2+were not conducive to the adsorption of low concentration Cu2+.The adsorption kinetics of WS-HFO for Cu2+followed pseudo-second dynamics equation,the adsorption isotherm conformed to Langmuir model.WS-HFO had strong adsorption affinity for Cu2+.The fixed-bed column adsorption/desorption running showed that 1.8 g WS-HFO could effectively treat 1 980 mL simulated wastewater with the average effluent Cu2+concentration below 0.05 mg/L.When 4 mol/L NaCl was used as desorption agent,the removal rate of Cu2+could remain at 89％-100％in the 7 recycling tests.
关键词
麦秸秆/水合氧化铁/纳米复合材料/吸附/重金属Key words
wheat straw/hydrated iron oxide/nanocomposites/adsorption/heavy metal引用本文复制引用
基金项目
国家重点研发计划项目(2021YFD2200403)
中国博士后科学基金资助项目(2017M621755)
出版年
2024
NETL
NSTL
万方数据