Toral-Sánchez E, Hurt Robert H, Valdés Juan A Ascacio, Aguilar Cristóbal N, Cervantes F J, Rangel-Mendez J R
IPICYT/División de Ciencias Ambientales. Camino a la Presa San José 2055, Col. Lomas 4a. Sección, C.P. 78216, San Luis Potosí, SLP, México.
School of Engineering/Institute for Molecular and Nanoscale Innovation (IMNI), Brown University, Providence, Rhode Island 02912, United States.
Colloids Surf A Physicochem Eng Asp. 2019 Apr 5;566:188-195. doi: 10.1016/j.colsurfa.2019.01.026. Epub 2019 Jan 14.
The novel application of magnetite containing reduced graphene oxide nanosacks (MrGO-N) as electron shuttles to improve the reductive degradation of pharmaceutical pollutant, iopromide (IOP), was evaluated. The MrGO-N were synthesized by ultrasonicated nebulization process, and their physicochemical characterization was performed by potentiometric titrations, zeta potential, high resolution transmission electron microscopy (HR-TEM), X-ray diffraction, as well as by Raman and Fourier transform infrared spectroscopies. Results demonstrated the thermal reduction of precursor graphene oxide sheets, the removal of different oxygenated groups, and the successful assembly of magnetite nanoparticles (MNP) in the graphene sacks. Also, reduction experiments revealed 72 % of IOP removal efficiency and up to 2.5-fold faster degradation of this pollutant performed with MrGO-N as redox catalysts in batch assays and with sulfide as electron donor. Chemical transformation pathway of IOP provides evidence of complete dehalogenation and further transformation of aromatic ring substituents. Greater redox-mediating ability of MrGO-N was observed, which was reflected in the catalytic activity of these nanomaterials during the reductive degradation of IOP. Transformation byproducts with simpler chemical structure were identified, which could lead to complete degradation by conventional methodologies in a complementary treatment process. Redox-mediating activity of MrGO-N could potentially be applied in wastewater treatment systems in order to facilitate the biodegradation of priority contaminants.
评估了含磁铁矿的还原氧化石墨烯纳米袋（MrGO-N）作为电子穿梭体在改善药物污染物碘普罗胺（IOP）还原降解方面的新应用。通过超声雾化法合成了MrGO-N，并通过电位滴定、zeta电位、高分辨率透射电子显微镜（HR-TEM）、X射线衍射以及拉曼光谱和傅里叶变换红外光谱对其进行了物理化学表征。结果表明前驱体氧化石墨烯片发生了热还原，不同的含氧基团被去除，并且磁铁矿纳米颗粒（MNP）成功组装在石墨烯袋中。此外，还原实验表明，在分批试验中以MrGO-N作为氧化还原催化剂且以硫化物作为电子供体时，IOP的去除效率为72%，该污染物的降解速度加快了2.5倍。IOP的化学转化途径提供了完全脱卤以及芳环取代基进一步转化的证据。观察到MrGO-N具有更强的氧化还原介导能力，这体现在这些纳米材料在IOP还原降解过程中的催化活性上。鉴定出了化学结构更简单的转化副产物，在互补处理过程中，这些副产物可通过传统方法实现完全降解。MrGO-N的氧化还原介导活性可能应用于废水处理系统，以促进优先污染物的生物降解。
