Min Lingli, Ma Yahui, Zhang Bi, He Dulan, Chen Jinhua, Li Xuerong, Wang Shuhua, Chi Yulang
College of Resources and Environmental Science, Quanzhou Normal University, Quanzhou 362000, China.
College of Oceanology and Food Science, Quanzhou Normal University, Quanzhou 362000, China.
Toxics. 2024 Mar 21;12(3):230. doi: 10.3390/toxics12030230.
Efficient removal of extremely mobile and toxic As(III) from water is a challenging but critical task. Herein, we developed a functionalized sorbent of chitosan nanofiber with iron-manganese (Fe-Mn@CS NF) using a one-step hybrid electrospinning approach to remove trace As(III) from water. Batch adsorption studies were performed to determine the adsorption efficiency under a variety of conditions, including contact time, starting concentration of As(III), ionic strength, and the presence of competing anions. The experimental results demonstrated that the concentration of As(III) dropped from 550 to less than 1.2 µg/L when using 0.5 g/L Fe-Mn@CS NF. This demonstrates the exceptional adsorption efficiency (99.8%) of Fe-Mn@CS NF for removing As(III) at pH 6.5. The kinetic tests revealed that the adsorption equilibrium was reached in 2.6 h, indicating a quick uptake of As(III). The ionic strength effect analysis showed that the adsorbed As(III) formed inner-sphere surface complexes with Fe-Mn@CS NF. The presence of SO or F had a negligible impact on As(III) uptake, while the presence of PO impeded As(III) absorption by competing for adsorption sites. The exhausted sorbent could be effectively regenerated with a dilute NaOH solution. Even after 10 cycles of regenerating Fe-Mn@CS NF, the adsorption efficiency of As(III) in natural groundwater was maintained over 65%. XPS and FTIR analyses show that the presence of M-OH and C-O groups on the sorbent surface is essential for removing As(III) from water. Overall, our study highlights the significant potential of Fe-Mn@CS NF for the efficient and quick elimination of As(III) from water.
从水中高效去除极易迁移且有毒的三价砷（As(III)）是一项具有挑战性但至关重要的任务。在此，我们采用一步混合静电纺丝法制备了一种铁锰功能化的壳聚糖纳米纤维吸附剂（Fe-Mn@CS NF），用于去除水中的痕量As(III)。进行了批量吸附研究，以确定在各种条件下的吸附效率，包括接触时间、As(III)的起始浓度、离子强度以及竞争阴离子的存在。实验结果表明，使用0.5 g/L的Fe-Mn@CS NF时，As(III)的浓度从550 μg/L降至低于1.2 μg/L。这表明Fe-Mn@CS NF在pH 6.5时对去除As(III)具有卓越的吸附效率（99.8%）。动力学测试表明，吸附平衡在2.6小时内达到，表明As(III)的快速摄取。离子强度效应分析表明，吸附的As(III)与Fe-Mn@CS NF形成内球表面络合物。SO或F的存在对As(III)的摄取影响可忽略不计，而PO的存在通过竞争吸附位点阻碍了As(III)的吸收。耗尽的吸附剂可用稀NaOH溶液有效再生。即使经过10次Fe-Mn@CS NF的再生循环，天然地下水中As(III)的吸附效率仍保持在65%以上。XPS和FTIR分析表明，吸附剂表面M-OH和C-O基团的存在对于从水中去除As(III)至关重要。总体而言，我们的研究突出了Fe-Mn@CS NF在高效快速去除水中As(III)方面的巨大潜力。
