In this work, a novel adsorbent, sulfonic acid-functionalized carbon nanotubes (CNT-FA-SA) composite was synthesized by Diels-Alder (DA) chemistry and electrophilic substitution reaction. The adsorption of methylene blue (MB) onto CNT-FA-SA was systematically investigated. Based on the experimental data, MB was rapidly removed by CNT-FA-SA composite with maximum adsorption capacity of 236.55 mg/g under certain conditions. The non-linear relevant fitting result of Langmuir isotherm model fully estimates that the maximum adsorption capacity of monolayer can reach to 1584.22 mg/g. The adsorption kinetic is fitted better with the pseudo-second-order model than the pseudo-first-order kinetic model, and the isotherms were well described by Freundlich isotherm model. The data testified that the adsorption process is monitored by chemisorption and physical adsorption simultaneously. Relevant results also indicate that the adsorption occurred on heterogeneous multilayer surface. The parameters of pH and thermodynamic manifested that adsorption of MB onto CNT-FA-SA composites was pH-dependent and spontaneous endothermic reaction.

在这项工作中，通过Diels-Alder（DA）化学和亲电取代反应合成了一种新型的吸附剂，磺酸官能化的碳纳米管（CNT-FA-SA）复合材料。系统研究了亚甲基蓝（MB）在CNT-FA-SA上的吸附。根据实验数据，在一定条件下，CNT-FA-SA复合材料可快速去除MB，最大吸附容量为236.55 mg / g。Langmuir等温线模型的非线性相关拟合结果完全估计出单层的最大吸附容量可以达到1584.22 mg / g。拟二阶模型比拟一阶模型更适合吸附动力学，等温线可用弗氏等温线模型很好地描述。数据证明，吸附过程是通过化学吸附和物理吸附同时进行的。相关结果还表明吸附发生在异质多层表面上。pH和热力学参数表明，MB在CNT-FA-SA复合材料上的吸附是pH依赖性的并且是自发吸热反应。