Process Intensification of Tetracycline Hydrochloride Degradation via Ozone/Peroxymonosulfate in a High-Gravity Rotating Packed Bed

This study presents a novel process intensification strategy for the degradation of tetracycline hydrochloride (TCH) by integrating the liquid detention phenomenon (LDP) into an ozone/peroxymonosulfate (O3/PMS) system within a rotating packed bed (RPB). To address the inherent limitation of short liquid residence time in conventional high-gravity reactors, the introduction of a detained liquid volume (DLV) significantly prolonged the contact duration and enhanced the liquid holdup. Results indicated that an optimal DLV of 200 mL yielded remarkable improvements, boosting ozone absorption, TCH degradation, and COD removal efficiencies by 77.8%, 7.1%, and 75.0%, respectively, compared to the non-detention mode. Mechanistically, the presence of PMS not only complemented ozonation but was also effectively activated by ozone to generate a dual-radical system (·OH and SO4·−), leading to deep mineralization of pollutants. Furthermore, a systematic investigation of operating parameters revealed a critical trade-off between mass transfer enhancement and residence time reduction. Overall, this work demonstrates that the RPB/O3/PMS process coupled with liquid detention effectively overcomes mass-transfer and reaction-time bottlenecks, offering a promising, high-efficiency solution for the treatment of antibiotic-contaminated wastewater.