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

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.