Cheng Jiaqi, Zhan Conghua, Wu Jiahui, Cui Zhixiang, Si Junhui, Wang Qianting, Peng Xiangfang, Turng Lih-Sheng
School of Materials Science and Engineering, Fujian University of Technology, Fuzhou, Fujian 350118, China.
Fujian Provincial Key Laboratory in the Universities of Polymer Materials and Production, Fuzhou, Fujian 350118, China.
ACS Omega. 2020 Mar 2;5(10):5389-5400. doi: 10.1021/acsomega.9b04425. eCollection 2020 Mar 17.
A new type of deacetylated cellulose acetate (DA)@polydopamine (PDA) composite nanofiber membrane was fabricated by electrospinning and surface modification. The membrane was applied as a highly efficient adsorbent for removing methylene blue (MB) from an aqueous solution. The morphology, surface chemistry, surface wettability, and effects of operating conditions on MB adsorption ability, as well as the equilibrium, kinetics, thermodynamics, and mechanism of adsorption, were systematically studied. The results demonstrated that a uniform PDA coating layer was successfully developed on the surface of DA nanofibers. The adsorption capacity of the DA@PDA nanofiber membrane reached up to 88.2 mg/g at a temperature of 25 °C and a pH of 6.5 after adsorption for 30 h, which is about 8.6 times higher than that of DA nanofibers. The experimental results showed that the adsorption behavior of DA@PDA composite nanofibers followed the Weber's intraparticle diffusion model, pseudo-second-order model, and Langmuir isothermal model. A thermodynamic analysis indicated that endothermic, spontaneous, and physisorption processes occurred. Based on the experimental results, the adsorption mechanism of DA@PDA composite nanofibers was also demonstrated.
通过静电纺丝和表面改性制备了一种新型的脱乙酰化醋酸纤维素（DA）@聚多巴胺（PDA）复合纳米纤维膜。该膜被用作从水溶液中去除亚甲基蓝（MB）的高效吸附剂。系统研究了该膜的形态、表面化学、表面润湿性、操作条件对MB吸附能力的影响以及吸附的平衡、动力学、热力学和机理。结果表明，在DA纳米纤维表面成功形成了均匀的PDA涂层。在25℃、pH值为6.5的条件下吸附30 h后，DA@PDA纳米纤维膜的吸附容量达到88.2 mg/g，约为DA纳米纤维的8.6倍。实验结果表明，DA@PDA复合纳米纤维的吸附行为符合韦伯颗粒内扩散模型、准二级模型和朗缪尔等温模型。热力学分析表明，吸附过程为吸热、自发的物理吸附过程。基于实验结果，还阐述了DA@PDA复合纳米纤维的吸附机理。
