Department of Post-Graduate Studies and Research in Chemistry, Mangalore University, Mangalagangothri 574199, (D.K.), Karnataka, India.
Department of Post-Graduate Studies and Research in Chemistry, Mangalore University, Mangalagangothri 574199, (D.K.), Karnataka, India.
Int J Biol Macromol. 2020 Dec 15;165(Pt A):542-553. doi: 10.1016/j.ijbiomac.2020.09.202. Epub 2020 Sep 28.
A novel polysaccharide based hydrogel; kappa-carrageenan grafted with N-hydroxyethylacrylamide (κC-g-PHEAA) was synthesized via microwave assisted free radical polymerization process. A hybrid nanocomposite has also been made by incorporation of FeO nanoparticles into the κC-g-PHEAA network. The materials were characterized by FTIR, TGA, XRD, SEM, BET and VSM techniques. The nanocomposite exhibited super-paramagnetic behavior. The κC-g-PHEAA and κC-g-PHEAA/FeO presented significant adsorption capacity towards cationic dyes, methylene blue (MB) and rhodamine 6G (R6G); and metal ions, Cu(II) and Hg(II) from aqueous solution. The magnetite nanoparticles enhance the adsorption characteristics of the hydrogel and enables easy separation of the adsorbent with an external magnetic field. Adsorption process is observed to follow both Langmuir and Freundlich isotherm models for R6G and Freundlich isotherm model for MB, Cu(II) and Hg(II). The adsorption was found to be a pseudo first order process for MB and pseudo second order process for R6G, Cu(II) and Hg(II). Thermodynamic studies have shown the adsorption of dyes and metal ions to be spontaneous and endothermic in nature. The desorption studies revealed the efficient recovery of adsorbate species. The study indicates that the synthesized adsorbents have potential applications for the removal of dyes and metal ions from wastewater.
一种新型多糖基水凝胶；通过微波辅助自由基聚合过程合成了 N-羟乙基丙烯酰胺接枝角叉菜胶（κC-g-PHEAA）。通过将 FeO 纳米粒子掺入 κC-g-PHEAA 网络中，还制备了一种杂化纳米复合材料。通过傅里叶变换红外光谱（FTIR）、热重分析（TGA）、X 射线衍射（XRD）、扫描电子显微镜（SEM）、BET 和振动样品磁强计（VSM）技术对材料进行了表征。纳米复合材料表现出超顺磁性。κC-g-PHEAA 和 κC-g-PHEAA/FeO 对阳离子染料亚甲基蓝（MB）和罗丹明 6G（R6G）以及金属离子 Cu(II)和 Hg(II)具有显著的吸附能力从水溶液中。磁铁矿纳米粒子增强了水凝胶的吸附特性，并使吸附剂能够在外磁场作用下方便地分离。吸附过程观察到 R6G 遵循 Langmuir 和 Freundlich 等温线模型，MB 遵循 Freundlich 等温线模型，Cu(II)和 Hg(II)遵循 Freundlich 等温线模型。吸附对 MB 和 R6G 为拟一级过程，对 Cu(II)和 Hg(II)为拟二级过程。热力学研究表明，染料和金属离子的吸附是自发的和吸热的。解吸研究表明吸附剂物种的有效回收。研究表明，合成的吸附剂具有从废水中去除染料和金属离子的潜在应用。
