Fe0/Fe₃O₄/ultra-stable Y zeolite for energy-efficient solar photo-Fenton degradation and mineralization of chloramphenicol in aqueous matrices

Ultrastable Y (USY) zeolites with different Si/Al ratios were used as a support for Fe 0 and Fe 3 O 4 , loaded via vacuum impregnation of ferrous solutions followed by thermal treatment in a reducing atmosphere. The influence of Fe 0 /Fe 3 O 4 ratios in the magnetically recoverable Fe 0 /Fe 3 O 4 /USY composite catalysts was explored in the solar-assisted photo-Fenton degradation of chloramphenicol (CAP), a recalcitrant antibiotic frequently detected in pharmaceutical wastewater. Under optimized conditions (pH = 4, H₂O₂ dosage = 0.12 g L −1 , catalyst loading = 1.5 g L −1 ), the Fe 0 (3.3 %)/Fe₃O₄(1.6 %)/USY catalyst achieved 98 % CAP degradation within 30 min in the dark and 52 % TOC removal after 120 min under simulated solar irradiation. Scavenger and band structure analyses revealed that hydroxyl radicals were the primary oxidative species responsible for CAP degradation. The catalyst exhibited excellent reusability and maintained high activity in the presence of common inorganic ions present in real water matrix, confirming its robustness under realistic water treatment conditions. A comparative energy consumption analysis demonstrated that the proposed system requires significantly lower energy input compared to similar photocatalytic and photo-Fenton processes reported in the literature. These findings highlight the potential of Fe 0 /Fe 3 O 4 /USY as a cost-effective and sustainable solution for the removal of emerging pharmaceutical contaminants from aqueous environments. • Fe 0 /Fe₃O₄/USY catalysts enabled 98 % CAP degradation and 52 % TOC removal. • Fe 0 drives dark-phase CAP reduction; Fe₃O₄ sustains light-driven mineralization. • Optimal pH = 4 enhances OH formation and maximizes photo-Fenton efficiency. • The catalyst is reusable over 5 cycles with no Fe leaching and high activity. • The optimal Fe 0 /Fe₃O₄/USY achieves lower E E/O than light-assisted CAP treatments.