短毛蓼粉末对Cd(Ⅱ)和Cu(Ⅱ)的吸附研究  

Adsorption of Cd(Ⅱ)and Cu(Ⅱ)from Aqueous Solutions by Polygonum Pubescens Blume Powder

作　　者：邓华[1,2] 李秋燕[1,2] 周瑞爽 庞舒月 刘金玉 康彩艳 DENG Hua;LI Qiuyan;ZHOU Ruishuang;PANG Shuyue;LIU Jinyu;KANG Caiyan(Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection(Guangxi Normal University),Guilin Guangxi 541006,China;College of Environment and Resources,Guangxi Normal University,Guilin Guangxi 541006,China)

机构地区：[1]广西师范大学珍稀濒危动植物生态与环境保护教育部重点实验室,广西桂林541006 [2]广西师范大学环境与资源学院,广西桂林541006

出　　处：《广西师范大学学报（自然科学版）》2021年第3期102-112,共11页Journal of Guangxi Normal University:Natural Science Edition

基　　金：国家自然科学基金(41301343)。

摘　　要：本文以超富集锰植物短毛蓼为研究对象,将短毛蓼粉末制备成吸附剂,采用批量吸附试验的方法,研究溶液pH值、吸附剂投加量、重金属离子初始浓度、温度和时间等对短毛蓼粉末吸附Cd(II)和Cu(II)的影响,通过动力学、等温模型拟合以及FT-IR、SEM-EDS、XRD表征分析,对吸附机理进行探究。结果表明,短毛蓼粉末对Cd(II)和Cu(II)吸附的最佳pH分别为8和7,最佳投加量均为0.25 g,吸附平衡时间为60 min。短毛蓼粉末对Cd(II)和Cu(II)吸附均符合准二级动力学模型,对Cu(II)的吸附符合Langmuir模型,最大理论吸附量为90.01 mg/g,对Cd(II)的吸附符合Freundlich模型,最大理论吸附量为62.69 mg/g;吸附热力学分析表明Cd(II)和Cu(II)的ΔG、ΔH均为负值,表明吸附过程均为自发的放热过程;Cd(II)和Cu(II)的吸附主要通过氢键作用、离子交换作用及阳离子-π作用等协同进行。In this paper, the effects of pH value, dosage, initial concentration, temperature and adsorption time on the adsorption of Cd(Ⅱ) and Cu(Ⅱ) by polygonum pubescens blume powder were studied by batch adsorption test with polygonum pubescens blume powder(hyperaccumulating manganese plant) as the research object. The adsorption mechanism was explored through kinetics, isothermal model fitting, FT-IR, SEM-EDS and XRD characterization analysis. The results showed that the optimum pH for adsorption of Cd(Ⅱ) and Cu(Ⅱ) by polygonum pubescens blume powder was 8 and 7, respectively, and the optimum dosage was 250 mg, and the adsorption equilibrium time was 60 min. The adsorption of Cd(Ⅱ) and Cu(Ⅱ) were in accordance with the quasi-second-order kinetic model. The adsorption of Cu(Ⅱ) was in accordance with Langmuir model, and the maximum theoretical adsorption capacity was 90.01 mg/g. The adsorption of Cd(Ⅱ) was in accordance with Freundlich model, and the maximum theoretical adsorption capacity was 62.69 mg/g. The adsorption thermodynamic analysis shows that the values of ΔG and ΔH are all negative, indicating that the adsorption process is spontaneous exothermic process. The results showed that the adsorption of Cd(Ⅱ) and Cu(Ⅱ) by polygonum pubescens blume powder were mainly carried out by hydrogen bonding, ion exchange and cation exchange-π interactions.

关 键 词：短毛蓼粉末 镉 铜 吸附 吸附机理 

分 类 号：X703[环境科学与工程—环境工程] X52