Oxidation process using singlet oxygen specifically breaks down oxytetracycline in a manner resembling Fenton's reaction
In a groundbreaking development, a team of researchers led by Prof. Kong Lingtao at the Hefei Institutes of Physical Science (HFIPS) of the Chinese Academy of Sciences (CAS) have devised a novel method for activating hydrogen peroxide (H2O2) to produce singlet oxygen, which selectively degrades oxytetracycline (OTC) in complex water matrices. The research was published in the Chemical Engineering Journal with the DOI 10.1016/j.cej.2021.129594.
The study focuses on the preparation of a type of hollow amorphous Co/C composites, which feature a large number of oxygen-containing functional groups such as carbonyl and hydroxyl distributed on the surface. By optimizing the ratio of cobalt and carbon, the researchers obtained the Co/C-3 material, which plays a crucial role in activating H2O2 to form singlet oxygen.
The synergistic interaction between cobalt and oxygen-containing functional groups within the materials is key to this activation. Quenching experiments and Electron Paramagnetic Resonance results confirm that converted singlet oxygen is the main oxidizing species, and hydroxyl radical doesn't appear in the system.
OTC, the most common tetracycline antibiotic in the field of animal husbandry, cannot be effectively removed by conventional technical means. The catalytic degradation system developed by the research group led by Prof. Chen Wei at HFIPS exhibits excellent repeatability, stability, and anti-interference ability. The researchers achieved the catalytic degradation of 20 ppm OTC by activating H2O2 under neutral pH conditions.
Fenton-like oxidation has been considered an effective way for water pollution, but the yield of singlet oxygen is low in most reactions. This new method offers a promising solution to this issue. The study also reveals the possible degradation pathways and potential ecological toxicities of OTC and its intermediates.
The research was supported by the National Key R&D Program, the National Natural Science Foundation of China, the Anhui Provincial Major Science and Technology Project, and the USTC Supercomputing Center. This innovative work paves the way for the development of more efficient and environmentally friendly methods for removing antibiotic pollutants from complex water matrices.
