摘要
      污泥中含有大量的抗生素抗性基因（ARGs），这些基因在传播给人类时会降低抗生素治疗的效果。然而，传统的污泥处理往往无法去除ARGs。在此，进行了临界酸螯合Fe（II）催化过氧化（CA Fenton），以同时提高污泥的脱水性和ARGs的去除率。结果表明，CA-Fenton工艺显著提高了污泥脱水性能和ARGs去除率，其中污泥的毛细管抽吸时间（CST）、比过滤阻力（SRF）和滤饼含水量分别从8.8s·L/g、5.8×1013m/kg和93.2%降至2.3s·L/g、5.8×1012m/kg和79.1%，污泥中7种ARGs的去除率均达到90%以上。此外，通过一系列宏观和光谱证据（高效液相色谱-尺寸排阻色谱（HPLC-SEC）和二维傅立叶变换红外相关光谱（2D-FTIR））阐明了协同污泥脱水和ARGs降解机制。在CA Fenton处理过程中，CA酸化增强了EPS中细胞屏障的通透性，将细胞内ARGs释放到污泥本体溶液中，通过CA螯合Fe（II）催化的H2O2过程加速了ARGs的降解。同时，蛋白质中以β-转向为代表的二级结构的破坏增强了EPS的疏水性，有助于提高污泥的脱水性。该研究不仅提出了一种改进传统Fenton氧化污泥处理的有效方法，而且为更好地理解CA Fenton工艺提供了机理基础，使污泥能够进行无害化处理。
Abstract
Sludge contains large amounts of antibiotic resistance genes (ARGs), that reduce the efficacy of antibiotic therapies when transmitted to humans. However, conventional sludge treatment often fails to remove ARGs. Herein, critic acid chelated Fe(II) catalyzed peroxidation (CA-Fenton) was conducted to simultaneously improve sludge dewaterability and ARGs removal. As results, the CA-Fenton process exhibited significantly improved sludge dewatering performance and ARGs removal, in which the capillary suction time (CST), specific resistance to filtration (SRF) and cake moisture of sludge were reduced from 8.8 s·L/g, 5.8 × 1013 m/kg and 93.2% to 2.3 s·L/g, 5.8 × 1012 m/kg and 79.1%, respectively, and the removal efficiencies of 7 types-ARGs in sludge achieved over 90%. In addition, synergistic sludge dewatering and ARGs degradation mechanisms were elucidated with a suit of macro and spectroscopic evidence (high performance liquid chromatography-size exclusion chromatography (HPLC-SEC) and two-dimensional fourier-transform infrared correlation spectroscopy (2D-FTIR)). During CA-Fenton treatment, CA acidification enhanced permeability of the cell barrier in EPS, releasing intracellular ARGs into sludge bulk solution, which accelerated the ARGs degradation via CA chelated Fe(II) catalyzed H2O2 process. Meanwhile, destruction of secondary structure represented β-turn in proteins enhanced the hydrophobicity of EPS, which contributed the improvement of sludge dewaterability. The study not only proposed an efficient method to improve traditional Fenton oxidation for sludge treatment, but also provided a mechanistic basis for better understanding of the CA-Fenton process, and enable the harmless disposal for sludge.

https://www.sciencedirect.com/science/article/abs/pii/S1383586621016324