Co3O4 confined in activated carbon-supported Mg/Al-LDH for µM peroxymonosulfate activation with minute-level antibiotics degradation

• Published in: Chemical engineering journal (Lausanne, Switzerland : 1996) Vol. 516; p. 163872
• Main Authors: Li, Tao, Sun, Weikun, Zhang, Jian, Liu, Shengqin, Chen, Hongbin, Qiu, Zumin, Lam, Jason Chun-Ho
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.07.2025
• Subjects: Confined catalysis; Flower-like Mg/Al-LDH; Hospital wastewater treatment; Ultra-fast antibiotics degradation; µM peroxymonosulfate; Ultra-fast antibiotics degradation; Flower-like Mg/Al-LDH; Hospital wastewater treatment; Confined catalysis; µM peroxymonosulfate
• ISSN: 1385-8947
• DOI: 10.1016/j.cej.2025.163872

•5Co3O4@LDH-AC was innovatively designed by confining Co3O4 in activated carbon supported Mg/Al-LDH.•5Co3O4@LDH-AC exhibited ultra-fast degradation efficiency of levofloxacin within 4 min.•Ultra-fast degradation of levofloxacin achieved through µM addition of peroxymonosulfate.•5Co3O4@LDH-AC + PMS system shown excellent stability in treating real wastewater from hospital effluent. Herein, an efficient and stable catalyst of Co3O4@LDH-AC was innovatively prepared through uniform loading of an activated carbon substrate with Mg/Al layered double hydroxide (Mg/Al-LDH) followed by dispersing Co3O4 nanoparticles in the confined space of LDH. This unique flower-like spherical structure significantly improved the adsorption capacity and would increase the concentration of reactants in the confined space. Experimental results showed that levofloxacin (LFX) completely degraded in 4 min with the addition of µM peroxymonosulfate (PMS). The fast conversion of Co2+ and Co3+ in catalyst for the generation of highly reactive species is revealed via EPR, in-situ Raman, in-situ FT-IR, and XPS. Further tests of 5Co3O4@LDH-AC in effluent of hospital wastewater treatment showed that it not only possessed strong anti-interference capabilities, but also maintained stable catalytic activity in fixed-bed reactor for a long operation time. Therefore, the excellent catalytic performance in confined space offers the possibility of application for the degradation of micropollutants in real pharmaceutical wastewater discharged from hospital (800–1200 tons/day, COD > 150 mg/L).