Degradation of antibiotic pollutants and simultaneous CO₂ capture over hollow MnO₂/light/peroxymonosulfate (PMS)-CaO...

Antibiotic organic pollutants not only pose a significant threat to human health but also generate a large amount of carbon dioxide (CO₂) during the treatment process of advanced oxidation processes (AOPs). Herein, the antibiotics aqueous solution was firstly degraded and mineralized by light-assisted peroxymonosulfate (PMS) activation over hollow manganese dioxide (MnO₂) catalyst and then the corresponding released CO₂ was effectively captured by calcium oxide (CaO) particles in the same sealed reactor, achieving wastewater treatment with zero carbon releasing. Under simulated light conditions, hollow MnO₂ is excited to generate electron-hole pairs. The photo-induced electrons activate PMS, producing reactive oxygen species (ROS) such as SO₄·^-, ¹O₂, ·O₂^- and ·OH, which subsequently attack and degrade tetracycline (TC), resulting in the formation of CO₂. After 3 h reaction, 99 % of TC was degraded while the concentration of CO₂ in the sealed reaction jar increased from ca.410 ppm to ca.3066 ppm. Consequently, CaO in the same reactor captured released CO₂ with the concentration decreased to 310 ppm. The capture of CO₂ in the system exhibited a negligible effect on the TC degradation efficiency. This study provides a new system for the high-efficiency and low-carbon degradation of antibiotics wastewater.