Efficient degradation of N, N-dimethylacetamide using high-porosity activated carbon loaded with MnRu combined with ozone without sludge formation

Traditional methods for N, N-dimethylacetamide (DMAC) degradation often generate excessive sludge and have high operational costs. This study proposes an advanced oxidation process (AOP) based on manganese- and ruthenium-loaded activated carbon (AC-MnRu) combined with ozone to overcome these challenges. Characterization using scanning electron microscopy, high resolution transmission electron microscopy, X-ray adsorption near-edge structure, X-ray photoelectron spectroscopy, Raman spectrometer and x-ray diffraction confirmed the structural and chemical properties of AC-MnRu. Under optimal conditions (catalyst dosage: 20 g L -1 , pH 10, ozone flow rate: 2.8 g h -1 , 80 °C, DMAC initial concentration of 1800 mg L -1 ), the catalyst achieved over 95% DMAC degradation and 98% chemical oxygen demand (COD) removal during the initial cycle. This significantly outperformed AC oxidation (25% COD and 35% DMAC removal) and ozone oxidation alone (14% COD and 30% DMAC removal), with no sludge formation. Furthermore, long-term stability tests demonstrated that the AC-MnRu/O₃ system maintained 89% DMAC removal after six reuse cycles, confirming sustained catalytic activity. Radical scavenging experiments identified hydroxyl radicals, superoxide radicals, and singlet oxygen as key reactive species. Additionally, in real wastewater treatment, the AC-MnRu/O₃ system achieved 80% DMAC removal and 78% COD removal after six cycles (initial COD: 1542 mg L -1 , DMAC: 770 mg L -1 ), demonstrating its potential for industrial applications. These results highlight the potential of the AC-MnRu/O₃ system as a robust and sustainable treatment strategy for high-strength industrial wastewater.