Jian Shaoju, Chen Yuhuang, Shi Fengshuo, Liu Yifei, Jiang Wenlong, Hu Jiapeng, Han Xiaoshuai, Jiang Shaohua, Yang Weisen
Fujian Key Laboratory of Eco-Industrial Green Technology, Key Laboratory of Green Chemical Technology of Fujian Province University, College of Ecology and Resources Engineering, Wuyi University, Wuyishan 354300, China.
Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, International Innovation Center for Forest Chemicals and Materials, College of Materials Science and Engineering, Nanjing Forestry University, Nanjing 210037, China.
Polymers (Basel). 2022 Dec 11;14(24):5417. doi: 10.3390/polym14245417.
The occurrence of fluoride contamination in drinking water has gained substantial concern owing to its serious threat to human health. Traditional adsorbents have shortcomings such as low adsorption capacity and poor selectivity, so it is urgent to develop new adsorbents with high adsorption capacity, renewable and no secondary pollution. In this work, magnetic electrospun La-Mn-Fe tri-metal oxide nanofibers (LMF NFs) for fluoride recovery were developed via electrospinning and heat treatment, and its defluoridation property was evaluated in batch trials. Modern analytical tools (SEM, BET, XRD, FTIR) were adopted to characterize the properties of the optimized adsorbent, i.e., LMF11 NFs with a La:Mn molar ratio of 1:1. The surface area calculated via BET method and pH assessed using pH drift method of LMF11 NFs were 55.81 m g and 6.47, respectively. The results indicated that the adsorption amount was highly dependent on the pH of the solution, and reached the highest value at pH = 3. The kinetic behavior of defluoridation on LMF11 NFs was dominated by the PSO model with the highest fitted determination coefficients of 0.9999. Compared with the other three isotherm models, the Langmuir model described defluoridation characteristics well with larger correlation coefficients of 0.9997, 0.9990, 0.9987 and 0.9976 at 15 °C, 25 °C, 35 °C and 45 °C, respectively. The optimized LMF11 NFs exhibited superior monolayer defluoridation capacities for 173.30-199.60 mg F/g at pH 3 at 15-45 °C according to the Langmuir isotherm model. A thermodynamic study proved that the defluoridation by LMF11 NFs is a spontaneous, endothermic along with entropy increase process. In addition, the LMF11 NFs still showed high defluoridation performance after three reused cycles. These findings unveil that the synthesized LMF11 NFs adsorbent is a good adsorbent for fluoride remediation from wastewater owing to its low cost, high defluoridation performance and easy operation.
饮用水中氟化物污染的发生因其对人类健康的严重威胁而受到广泛关注。传统吸附剂存在吸附容量低、选择性差等缺点，因此迫切需要开发具有高吸附容量、可再生且无二次污染的新型吸附剂。在这项工作中，通过静电纺丝和热处理制备了用于氟回收的磁性静电纺La-Mn-Fe三金属氧化物纳米纤维（LMF NFs），并在批量试验中评估了其除氟性能。采用现代分析工具（SEM、BET、XRD、FTIR）对优化后的吸附剂，即La:Mn摩尔比为1:1的LMF11 NFs的性能进行了表征。通过BET方法计算的LMF11 NFs的比表面积和使用pH漂移法评估的pH值分别为55.81 m²/g和6.47。结果表明，吸附量高度依赖于溶液的pH值，在pH = 3时达到最高值。LMF11 NFs上除氟的动力学行为以PSO模型为主，拟合决定系数最高为0.9999。与其他三种等温线模型相比，Langmuir模型在15℃、25℃、35℃和45℃时分别以0.9997、0.9990、0.9987和0.9976的较大相关系数很好地描述了除氟特性。根据Langmuir等温线模型，优化后的LMF11 NFs在15-45℃、pH 3时表现出173.30-199.60 mg F/g的优异单层除氟容量。热力学研究证明，LMF11 NFs除氟是一个自发、吸热且熵增加的过程。此外，LMF11 NFs在三个重复使用周期后仍表现出较高的除氟性能。这些发现表明，合成的LMF11 NFs吸附剂因其低成本、高除氟性能和易于操作，是一种用于从废水中去除氟化物的良好吸附剂。
