Removal of tetracycline by ultraviolet/sodium percarbonate (UV/SPC)advanced oxidation process in water.

Tetracycline (TC) was widely used and frequently detected in various water bodies, where the presence of TC posed a significant threat to the health of aquatic organisms. Furthermore, antibiotics were hardly degraded by biological treatment. Thus, in order to enhance the removal of TC, we proposed the use of a novel ultraviolet/sodium percarbonate (UV/SPC) advanced oxidation process and initiated an in-depth study. The study investigated the influence of oxidant dosage, initial pH, UV intensity, and TC concentration on the removal of TC. The results demonstrated that the UV/SPC system efficiently removed TC, with removal efficiency increasing as the SPC concentration increased. Within the pH range of 3-11, TC degradation exhibited minimal variation, indicating the UV/SPC system's strong adaptability to pH variations. The research on the impact of the water matrix on TC removal revealed that HCO had an inhibitory effect on TC degradation, while NO promoted TC degradation. Additionally, the presence of free radical species (·OH, ·CO, ·O) were detected and rate constants for the secondary reactions (k = 6.3 × 10 L mol·s, k = 3.4 × 10 L mol·s) were calculated, indicating that ·OH exhibited a stronger oxidative performance compared to ·CO. This study did not only present a novel strategy via UV/SPC to remove TC but also uncovered the unique role of ·CO for contaminant removal.