改性废棉对水溶液中Cu^(2+)的吸附性能

Adsorption of modified waste cotton to Cu^(2+) in aqueous solution

为扩展废棉的回用价值,利用柠檬酸对废棉进行羧基化改性,并研究其对水溶液中Cu^(2+)的吸附性能,分析了吸附时间、Cu^(2+)溶液初始浓度、p H值等参数对吸附性能的影响。研究结果表明,改性废弃棉对Cu^(2+)的吸附性能远远优于未改性废弃棉,并随吸附时间、Cu^(2+)溶液的初始浓度、p H值等参数的增加而增长,增长速度由大到小到不变。吸附平衡时间为300 min,初始质量浓度为1 400 mg/L,对Cu^(2+)的最大吸附量为116.4 mg/g,最佳吸附p H值为4~5。使用吸附动力学和吸附等温线模型来分析其吸附机制,结果表明:吸附动力学模型更符合伪二级动力学模型,改性废弃棉对Cu^(2+)吸附属于化学吸附;吸附等温线模型与Langmuir等温吸附模型更吻合,属于单层吸附。

In order to order to extend the recycling value of waste cotton,carboxyl modification of waste cotton was carried out,and the adsorption of Cu^（2＋） ions in aqueous solution was studied.The influence of adsorption time,the initial concentration of Cu^（2＋） solution and the p H value of the adsorbed liquid on the adsorption performance were analyzed.The results show that the properties of modified waste cotton are much better than that of unmodified waste cotton,and increase with the increase of adsorption time,the initial concentration of Cu^（2＋） solution and the p H value of adsorption solution.The increase rate is from high to low and then unchanged.The adsorption equilibrium time is 300 min,the initial concentration is 1 400 mg/L,the maximum adsorption capacity of Cu^（2＋） is 116.4 mg/g,and the optimum adsorption pH is 4-5.The adsorption mechanism of the modified cotton was studied by adsorption kinetics and adsorption isotherm model.The results show that the adsorption of modified waste cotton to Cu^（2＋） belongs to chemical adsorption.The adsorption kinetics model accords with the Pseudo-second-order kinetic model.The adsorption isotherm model agrees well with the Langmuir isotherm model and belongs to the monolayer adsorption.