黑孢藻对Cu(Ⅱ)的生物吸附及其影响因素

Biosorption of Cu(Ⅱ) from Aqueous by Pithophora roettleri and Its Influential Factors

重金属污染是威胁人类健康和生态安全的主要环境问题之一,近年来采用藻类吸附水环境中的重金属越来越受到关注。该文主要探究黑孢藻(Pithophora)对重金属铜的生物吸附作用,采用分批实验考察不同的pH、温度、初始离子浓度对藻类吸附Cu^(2+)能力的影响,并应用吸附等温模型、动力学、热力学及红外光谱技术(FTIR)对吸附机制进行探讨。结果表明,当初始离子浓度为20 mg/L时,黑孢藻对Cu^(2+)的去除率达到最大,为87.1%;当p H=6时,对Cu^(2+)的去除效果最佳,去除率为91.1%;热力学研究表明,黑孢藻对Cu^(2+)的吸附为吸热反应,升温可促进黑孢藻对Cu^(2+)的吸附,当温度升至303 K时,去除率达90.4%。准一级、准二级动力学模型均能描述黑孢藻吸附Cu^(2+)的过程,吸附等温线遵循Freundlich模型。分析吸附前后红外光谱差异,确定黑孢藻吸附Cu^(2+)的主要官能团为-CONH、HCO_(3)^(-)/CO_(3)^(2-)、SO_(4)^(2-)。该研究结果可为丝状绿藻在重金属污染水体修复中的应用提供参考。

Heavy metal pollution is one of the major environmental problems threatening human health and ecological security.The use of algae to adsorb heavy metals from water environment has attracted more and more attention in recent years.In order to explore the bioadsorption behavior of Cu^(2+)from wastewater by Pithophora roettleri,three factors including solution pH,temperature and initial concentration on biosorption were studied by batch experiments.In addition,the adsorption mechanism was researched by the method of adsorption isotherm,kinetics model,thermodynamics and FTIR.The results showed that when the initial ion concentration was 20 mg/L,the maximum removal efficiencies of Cu^(2+)was 87.1%;Pithophora roettleri could remove 91.1%of copper under pH of 6.Thermodynamic analysis indicated that the adsorption of Cu^(2+)by Pithophora roettleri was an endothermic reaction.When the temperature rose to 303 K,the removal rate reached 90.4%.The adsorption kinetics of Cu^(2+)by Pithophora roettleri followed both the first-order kinetics and second-order kinetics,and the biosorption equilibrium data fitted very well to the Freundlich isotherm model.The FTIR spectra of Pithophora roettleri was used to reveal the main function groups of biosorption,which were-CONH,HCO_(3)^-/CO_(3)^(2-)and SO_(4)^(2-).This research serves as an important reference for the application of filamentous green algae in the remediation of heavy metal polluted water.