纳米CuFe_2O_4/K_2S_2O_8非均相类Fenton体系对橙黄Ⅱ降解性能的研究

Degradation of Orange Ⅱ with the nano-CuFe_2O_4/K_2S_2O_8 heterogeneous Fenton-like system

采用柠檬酸辅助溶胶-凝胶法制备了纳米CuFe_2O_4,以其为非均相催化剂,开展了纳米CuFe_2O_4/K_2S_2O_8非均相类Fenton体系对橙黄Ⅱ降解性能的研究,考察了纳米CuFe_2O_4焙烧温度对其结构及催化性能的影响,探讨了初始pH、K_2S_2O_8投加量和橙黄Ⅱ初始浓度对该体系降解性能的影响,评价了纳米CuFe_2O_4的稳定性,并在此基础上,探究了纳米CuFe_2O_4/K_2S_2O_8非均相类Fenton体系对橙黄Ⅱ的降解机制。结果表明:(1)纳米CuFe_2O_4最佳焙烧温度为400℃,此焙烧温度下制备的纳米CuFe_2O_4晶型较好、比表面积较大、催化活性和稳定性较高;(2)在纳米CuFe_2O_4/K_2S_2O_8非均相类Fenton体系中,橙黄Ⅱ快速降解最适宜的反应条件为初始pH 5.3、K_2S_2O_8投加量0.5g/L、橙黄Ⅱ初始质量浓度20mg/L、纳米CuFe_2O_4投加量1g/L;(3)纳米CuFe_2O_4在反应中的稳定性较好,金属溶出量较低,可通过有效催化K_2S_2O_8分解为SO_4^-·和HO·,实现橙黄Ⅱ的开环降解。

CuFe2 O4 nanoparticles were prepared by sol gel combustion method and used as heterogeneous cata- lyst in the nano-CuFe2 O4/K2S2 O8 heterogeneous Fenton-like system for the degradation of Orange Ⅱ. Several signif- icant factors affecting the degradation of Orange Ⅱ such as preparation temperature,initial pH, K2S2O8 dosage and Orange Ⅱ initial concentration were investigated,and the stability of the as-prepared catalyst was also evaluated. On the basis of above research, the degradation mechanism of Orange Ⅱin the nano-CuFe8 O4/K8S8O8 heterogeneous Fenton-like system was studied. The results indicated that the optimum temperature for the preparation of the catalyst was 400℃ ,and with this temperature, better crystalline, larger surface area, higher catalytic activity and stability of the catalyst could be obtained. The optimum conditions for the effectively degradation of Orange Ⅱ in the nano- CuFe204/K2S2O8 heterogeneous Fentonqike system was initial pH 5.3,0.5 g/L K2S2O8,20 mg/L Orange Ⅱ and 1 g/L nano-CuFe8O4. Nano-CuFe2O4 also exhibited a high stability property with low concentration of metal ion disso lution and could effectively catalyze KeSz08 to generate SO4^-· and HO· ,degrading Orange Ⅱ via oxidative ring- opening reaction.