Application of dimensional analysis in sorption modeling of the styryl pyridinium cationic dyes on reusable iron based humic acid coated magnetic nanoparticles
Application of dimensional analysis in sorption modeling of the styryl pyridinium cationic dyes on reusable iron based humic acid coated magnetic nanoparticles
复制标题
量纲分析在苯乙烯基吡啶鎓阳离子染料在可重复使用的铁基腐殖酸包覆磁性纳米粒子吸附建模中的应用
DOI：
10.1016/j.chemosphere.2021.131699
复制
发表时间：
2022
期刊：
影响因子：
8.8
通讯作者：
O'Shea, Kevin E.
中科院分区：
文献类型：
--
作者：
Esmaeilian, Anahita;O'Shea, Kevin E.
阳离子染料存在于各种工业废水中，由于其致癌行为对人类健康构成严重威胁，必须在排放前去除。研究了铁基腐植酸包裹磁性纳米粒子(HA-MNPs)去除水中2-[4-(二甲氨基)苯乙烯基]-1-甲基吡啶(2-ASP)的性能。采用共沉淀法制备了HA-MNPs，并对其进行了表征。用荧光法测定了HA-MNPs对2-ASP的吸附，结果表明，HA-MNPs对2-ASP的吸附是有效的，最大吸附容量为8 mg/g。动力学和平衡研究表明，吸附过程符合准二级和Langmuir等温线模型。吸附速度较快，约70%的吸附在30min内完成。溶液pH值越高，总的去除效果越好。所观察到的吸附增加可以归因于带正电的2-ASP和带负电荷的HA-MNPs表面之间的静电吸引随着溶液pH的增加而增强。利用饱和吸附剂的氢氧化钠处理，实现了HA-MNPs的高效、重复再生。对HA-MNPs的再生实验表明，连续循环5次后，HA-MNPs的去除效率始终保持较高水平。量纲分析表明，为了得到实验数据证实的准确的吸附模型，应考虑初始浓度/剂量比。在此基础上，建立了适用于等温研究和去除效率预测的广义经验模型。这一发现将有助于吸附研究中的研究人员更有效地设计他们的实验，并开发改进的经验模型来预测去除。
Cationic dyes exist in various industrial wastewaters and removal prior to discharge is necessary due to their carcinogenic behavior which poses a serious threat to human health. Iron based humic acid coated magnetic nanoparticles (HA-MNPs) were evaluated for the removal of 2-[4-(dimethylamino) styryl]-1-methylpyridinium iodide (2-ASP) as a model compound for cationic styryl pyridinium dyes from aqueous media. HA-MNPs were prepared by co-precipitation and characterized. The adsorption of 2-ASP, measured by fluorescence, demonstrates HA-MNPs are efficient for the 2-ASP removal with a maximum adsorption capacity of ~8 mg/g. Kinetic behavior and equilibrium studies showed the adsorption process fits with pseudo 2nd order and Langmuir isotherm models. The adsorption is relatively fast with ~70% of the adsorption complete within 30 min. The overall removal increases by increasing solution pH. The observed increase in adsorption can be assigned to an enhanced electrostatic attraction between the positively charged 2-ASP and the increase in the negative charge on the HA-MNPs surface as a function of increasing solution pH. Effective and repetitive regeneration of the HA-MNPs was achieved using NaOH treatment of saturated sorbent. Regeneration of HA-MNPs showed that removal efficiency remains consistently high after five consecutive cycles. Dimensional analysis suggested that initial concentration/sorbent dose ratio should be considered for accurate sorption modeling confirmed by experimental data. Then generalized empirical models for isothermal study and removal efficiency prediction were accurately deduced. This finding will help researchers in sorption studies to design their experiments more efficiently and to develop improved empirical models in removal prediction.