Institute of Environmental Technology and Sustainable Development, Nguyen Tat Thanh University, 298-300A Nguyen Tat Thanh, District 4, Ho Chi Minh City, 755414, Vietnam.
NTT Hi-Tech Institute, Nguyen Tat Thanh University, 298-300A Nguyen Tat Thanh, District 4, Ho Chi Minh City, 755414, Vietnam.
Environ Sci Pollut Res Int. 2022 May;29(21):32120-32141. doi: 10.1007/s11356-022-18570-y. Epub 2022 Jan 11.
The present study reported the synthesis and utilization of a graphene-based hybrid nanocomposite (MnFeO/G) to mitigate several synthetic dyes, including methylene blue, malachite green, crystal violet, and Rhodamine B. This adsorbent was structurally analyzed by several physicochemical techniques such as X-ray diffraction, Fourier-transform infrared spectroscopy, scanning electron microscopy, Raman spectroscopy, N adsorption-desorption isotherm measurement, point of zero charge, and Boehm titrations. BET surface area of MnFeO/G was measured at 382.98 m/g, which was substantially higher than that of MnFeO. MnFeO/G possessed diverse surface chemistry properties with the presence of many functional groups such as carboxylic acid, phenolic, lactone, and basic groups. MnFeO/G was used to remove synthetic dyes in the aqueous media. The effect of many factors, e.g., concentration (5-50 mg/L), pH (4-10), dose (5-20 mg), and temperature (25-45 °C) on adsorption performance of MnFeO/G was conducted. Kinetic, isotherm, intraparticle, and thermodynamic models were adopted for investigating adsorption phenomenon of dyes on MnFeO/G. The maximum adsorption capacity of dyes over MnFeO/G was found as Rhodamine B (67.8 mg/g) < crystal violet (81.3 mg/g) < methylene blue (137.7 mg/g) < malachite green (394.5 mg/g). Some tests were performed to remove mixed dyes, and mixed dyes in the presence of antibiotics with total efficiencies of 65.8-87.9% after 120 min. Moreover, the major role of π-π stacking interaction was clarified to gain insight into the adsorption mechanism. MnFeO/G could recycle up to 4 cycles, which may be beneficial for further practical water treatment.
本研究报道了一种基于石墨烯的杂化纳米复合材料（MnFeO/G）的合成与利用，以减轻包括亚甲蓝、孔雀石绿、结晶紫和罗丹明 B 在内的多种合成染料的影响。该吸附剂通过 X 射线衍射、傅里叶变换红外光谱、扫描电子显微镜、拉曼光谱、N 吸附-解吸等温线测量、零电荷点和Boehm 滴定等多种物理化学技术进行了结构分析。MnFeO/G 的 BET 表面积测量值为 382.98 m/g，明显高于 MnFeO。MnFeO/G 具有多种表面化学性质，存在许多官能团，如羧酸、酚、内酯和碱性基团。MnFeO/G 用于去除水溶液中的合成染料。研究了许多因素对 MnFeO/G 吸附性能的影响，如浓度（5-50 mg/L）、pH（4-10）、剂量（5-20 mg）和温度（25-45°C）。采用动力学、等温线、内扩散和热力学模型来研究染料在 MnFeO/G 上的吸附现象。发现 MnFeO/G 对染料的最大吸附容量为罗丹明 B（67.8 mg/g）<结晶紫（81.3 mg/g）<亚甲蓝（137.7 mg/g）<孔雀石绿（394.5 mg/g）。进行了一些测试以去除混合染料，并在抗生素存在下去除混合染料，在 120 分钟后总效率为 65.8-87.9%。此外，还阐明了π-π 堆积相互作用的主要作用，以深入了解吸附机制。MnFeO/G 可回收 4 次，这可能有利于进一步的实际水处理。
