Rahnama Sara, Shariati Shahab, Divsar Faten
Department of Chemistry, Rasht Branch, Islamic Azad University, Rasht, Iran.
Department of Chemistry, Payame Noor University (PNU), Tehran, Iran.
Comb Chem High Throughput Screen. 2018;21(8):583-593. doi: 10.2174/1386207321666181019111211.
In this research, a novel magnetite titanium dioxide nanocomposite functionalized by amine groups (Fe3O4@SiO2@TiO2-NH2) was synthesized and its ability for efficient removal of Acid Fuchsine as an anionic dye from aqueous solutions was investigated.
The core-shell structure of Fe3O4@SiO2@TiO2 was prepared using Fe3O4 as magnetic core, tetra ethyl orthosilicate as silica and tetra butyl titanate as titanium source for shell. The synthesized nanocomposites (particle size lower than 44 nm) were characterized by FT-IR, XRD, DRS, SEM and TGA instruments. The various experimental parameters affecting dye removal efficiency were investigated and optimized using Taguchi fractional factorial design.
The synthesized adsorbent showed the highest removal efficiency of Acid Fuchsine (99 %) at pH= 3.5, without salt addition and during stirring at contact times less than 10 minutes. The study of kinetic models at two concentration levels showed the fast dye sorption on the surface of proposed nanocomposites with pseudo second order kinetic model (R2=1). Also, the fitting of Acid Fuchsine sorption data to Freundlich, Langmuir and Temkin isotherms suggested that Freundlich model gave a better fitting than other models (R2=0.9936, n=2).
Good chemical stability, excellent magnetic properties, very fast adsorption kinetics and high removal efficiency make the synthesized nanocomposite as a proper recoverable sorbent for removal of Acid Fuchsine dye from wastewaters.
本研究合成了一种新型的胺基功能化磁铁矿二氧化钛纳米复合材料（Fe3O4@SiO2@TiO2-NH2），并研究了其从水溶液中高效去除酸性品红这种阴离子染料的能力。
以Fe3O4为磁核、正硅酸四乙酯为硅源、钛酸四丁酯为壳层钛源制备Fe3O4@SiO2@TiO2的核壳结构。通过傅里叶变换红外光谱仪、X射线衍射仪、漫反射光谱仪、扫描电子显微镜和热重分析仪对合成的纳米复合材料（粒径小于44nm）进行表征。采用田口分数因子设计研究并优化了影响染料去除效率的各种实验参数。
合成的吸附剂在pH = 3.5、不添加盐且搅拌、接触时间小于10分钟的条件下，对酸性品红的去除效率最高（99%）。在两个浓度水平下对动力学模型的研究表明，拟二级动力学模型（R2 = 1）表明染料在所提出的纳米复合材料表面吸附迅速。此外，酸性品红吸附数据对弗伦德利希、朗缪尔和坦金等温线的拟合表明，弗伦德利希模型的拟合效果优于其他模型（R2 = 0.9936，n = 2）。
良好的化学稳定性、优异的磁性、非常快的吸附动力学和高去除效率使得合成的纳米复合材料成为从废水中去除酸性品红染料的合适的可回收吸附剂。
