College of Environment, Hohai University, Nanjing 210098, PR China.
Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing 210098, PR China; College of Environment, Hohai University, Nanjing 210098, PR China.
J Colloid Interface Sci. 2015 Apr 1;443:115-24. doi: 10.1016/j.jcis.2014.12.012. Epub 2014 Dec 11.
For this study, a novel adsorbent of γ-AlOOH @CS (pseudoboehmite and chitosan shell) magnetic nanoparticles (ACMN) with magnetic separation capabilities was developed to remove fluoride from drinking water. The adsorbent was first characterized, and then its performance in removing fluoride was evaluated. Kinetic data demonstrated rapid fluoride adsorption with more than 80% fluoride adsorption within the initial 20 min and equilibrium reached in 60 min. Based on the results of kinetic and isotherm models, the fluoride adsorption process on the ACMN's surface was a monolayer adsorption on a homogeneous surface. Thermodynamic parameters presented that the adsorption process is spontaneous and endothermic in nature. The mechanism for the adsorption involved electrostatic interaction and hydrogen bonding. Moreover, the calculated adsorption capacity of the ACMN for fluoride using the Langmuir model was 67.5 mg/g (20°C, pH=7.0±0.1), higher than other fluoride removal adsorbents. This nanoadsorbent performed well over a pH range of 4-10. The study found that PO4(3-) was the co-existing anion most able to hinder the nanoparticle's fluoride adsorption, followed by NO3(-) then Cl(-). Experimental results suggest that ACMN is a promising adsorbent for treating fluoride-contaminated water.
本研究开发了一种具有磁分离能力的新型γ-AlOOH@CS（拟薄水铝石和壳聚糖）磁性纳米粒子（ACMN）吸附剂，用于去除饮用水中的氟化物。首先对吸附剂进行了表征，然后评估了其去除氟化物的性能。动力学数据表明，氟离子的吸附非常迅速，在前 20 分钟内超过 80%的氟离子被吸附，60 分钟内达到平衡。基于动力学和等温线模型的结果，ACMN 表面上的氟离子吸附过程是在均匀表面上的单层吸附。热力学参数表明，吸附过程是自发的和吸热的。吸附机制涉及静电相互作用和氢键。此外，使用 Langmuir 模型计算出 ACMN 对氟化物的吸附容量为 67.5mg/g（20°C，pH=7.0±0.1），高于其他去除氟化物的吸附剂。该纳米吸附剂在 pH 值为 4-10 的范围内表现良好。研究发现，PO4(3-)是最能阻碍纳米颗粒吸附氟化物的共存阴离子，其次是 NO3(-)，然后是 Cl(-)。实验结果表明，ACMN 是一种很有前途的处理含氟水的吸附剂。
