Hubei Key Laboratory of Mineral Resources Processing and Environment, Wuhan University of Technology, Luoshi Road 122, Wuhan, Hubei, 430070, China; School of Resources and Environmental Engineering, Wuhan University of Technology, Luoshi Road 122, Wuhan, Hubei, 430070, China.
School of Resources and Environmental Engineering, Wuhan University of Technology, Luoshi Road 122, Wuhan, Hubei, 430070, China.
Environ Pollut. 2020 Feb;257:113574. doi: 10.1016/j.envpol.2019.113574. Epub 2019 Nov 6.
High-performance two-dimensional montmorillonite supported-poly (acrylamide-co-acrylic acid) hydrogel for dye removal was investigated. Montmorillonite cooperated with acrylamide and acrylic acid via polymerization, hydrogen-bond, amidation and electrostatic interactions to form the three-dimensional reticular-structured hydrogel with the free entrance for macromolecules. Adsorption tests revealed that the efficient removal (97%) for methylene blue at high concentration (200 mg/L) could be achieved via a small dose of hydrogel (0.5 g/L) within a short time (20 min). The excellent adsorption performance was profited from the electronegative surface and fully exposed reaction sites of two-dimensional montmorillonite, which could save the treatment cost and promote the removal effect compared with the conventional adsorbents. The adsorption process of methylene blue onto hydrogel could be fitted by both the pseudo-first-order and pseudo-second-order kinetics models, and the adsorption isotherm corresponded to the Sips model. The mechanism analysis based on Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy measurements illustrated that the reaction between carboxyl groups and methylene blue molecules as well as the cation-exchange enabled the hydrogel performing extraordinary adsorption efficiency.
研究了一种用于染料去除的高性能二维蒙脱石负载聚（丙烯酰胺-共-丙烯酸）水凝胶。蒙脱石通过聚合、氢键、酰胺化和静电相互作用与丙烯酰胺和丙烯酸配合，形成具有大分子自由入口的三维网状结构水凝胶。吸附实验表明，通过小剂量的水凝胶（0.5g/L）在短时间（20min）内可以实现对高浓度（200mg/L）亚甲基蓝的高效去除（97%）。二维蒙脱石的电负性表面和完全暴露的反应位点有助于其具有优异的吸附性能，与传统吸附剂相比，可节省处理成本并提高去除效果。亚甲基蓝在水凝胶上的吸附过程可以用伪一阶和伪二阶动力学模型拟合，吸附等温线符合 Sips 模型。基于傅里叶变换红外光谱和 X 射线光电子能谱测量的机理分析表明，羧基基团与亚甲基蓝分子之间的反应以及阳离子交换使水凝胶具有非凡的吸附效率。
