Decolorization of wastewater by Fenton oxidation process was conducted using Fe₃O₄/CuO and MnO₂-Fe₃O₄/CuO hybrid catalysts prepared via co-precipitation and impregnation methods, respectively. The chemical structure, surface area and porosity of hybrid nanoparticles were characterized using XRD, EDS, FE-SEM and BET techniques. The experimental results reveal that the introduction of MnO₂ to Fe₃O₄/CuO catalyst (i.e. MnO₂-Fe₃O₄/CuO) enhances the rate of decolorization reaction due to the larger catalyst surface area and narrower pore size distribution, in comparison with Fe₃O₄/CuO, as well as the direct oxidation of methylene blue via Mn⁴⁺ and Mn³⁺. In particular, MnO₂-Fe₃O₄/CuO revealed higher methylene blue removal efficiency than Fe₃O₄/CuO during 45 min reaction time (90% vs. 79%). Reaction analyses show that both catalysts follow a second-order reaction kinetic where MnO₂-Fe₃O₄/CuO exhibit a higher decolorization rate constant (118 vs. 57 L.mg⁻¹min⁻¹) toward removal of methylene blue (MB) dye. Additionally, the effect of reaction conditions including pH, dosage of hydrogen peroxide, and concentrations of catalyst and methylene blue on the catalytic performance of MnO₂-Fe₃O₄/CuO were investigated. The synthesized hybrid nanostructured catalyst, MnO₂-Fe₃O₄/CuO, revealed excellent color removal efficiency with high reusability after six runs (removal efficiency > 90%).

分别采用共沉淀法和浸渍法制备的Fe ₃ O ₄ / CuO和MnO ₂ -Fe ₃ O ₄ / CuO杂化催化剂，通过Fenton氧化法对废水进行脱色。利用XRD，EDS，FE-SEM和BET技术对杂化纳米颗粒的化学结构，表面积和孔隙率进行了表征。实验结果表明，将MnO ₂引入Fe ₃ O ₄ / CuO催化剂（即MnO ₂ -Fe ₃ O _4）中。与Fe ₃ O ₄ / CuO相比，由于催化剂表面积更大，孔径分布更窄，因此提高了脱色反应的速度，并且通过Mn ⁴⁺和Mn ³⁺直接氧化亚甲基蓝。特别地，在45分钟的反应时间内，MnO ₂ -Fe ₃ O ₄ / CuO显示出比Fe ₃ O ₄ / CuO更高的亚甲基蓝去除效率（90％对79％）。反应分析表明，两种催化剂均遵循二级反应动力学，其中MnO ₂ -Fe ₃ O ₄ / CuO表现出较高的脱色速率常数（118 vs. 57 L.mg^-1分钟^-1），以除去亚甲基蓝（MB）染料。另外，研究了pH，过氧化氢用量，催化剂和亚甲蓝浓度等反应条件对MnO ₂ -Fe ₃ O ₄ / CuO催化性能的影响。合成的杂化纳米结构催化剂MnO ₂ -Fe ₃ O ₄ / CuO表现出优异的脱色效率，六次运行后具有较高的可重复使用性（去除效率> 90％）。