Preparation And Performance Study Of FeCoBa Oxide Nanocrystals Fenton Catalysts

Fenton oxidation method had been widely used in wastewater treatment. But the problem in the application of homogeneous Fenton system was under a narrow applicable p H range. The leaching of iron content in the reaction system was higher than 1 mg /L.In order to solve the above problems, Fe Co Ba oxide nanocrystals was prepared and characterized as a catalyst by sol-gel method in the study. The proportion of the different components of catalysts was prepared in the experiment, while the catalysts were characterized and Fenton degradation of methylene blue. The catalyst has the best results in the degradation of degradation experiments was used in the optimization experiments of Fenton degradation conditions.First, Fe1Co0.5Ba2.5 oxide nanocrystals was prepared by the high temperature calcination method, SEM, XRD, ICP and XPS were used to characterize and analysis the Fe1Co0.5Ba2.5 oxide nanocrystals, in order to study the composition, structure and surface oxidation state of the catalyst, and the results showed that the element ratio of Fe1Co0.5Ba2.5 was Fe : Co : Ba=1 : 0.5 :2.5, the size of oxide nanocrystals was from 200 nm to 300 nm. The catalyst had a sheet stacking structure and the thickness was about 40 nm, There existed the diffraction peaks of Ba O, Co O and Fe2O3.Second, methylene blue(MB) was used as simulated wastewater for studying the catalytic performance and determining the optimum process conditions. The results showed that Fe1Co0.5Ba2.5 oxide nanocrystals had a strong catalytic performance and stability. The adsorption performance of the catalyst was weak, that was, the degradation of methylene blue was mainly through the heterogeneous Fenton reaction process. The best degradation process conditions: the degradation temperature was 55 ℃, H2O2 dosage was 0.6 m L, catalyst dosage was 0.0120 g, the initial p H value 11, the reaction 20 min methylene blue degradation rate reached more than 90%,and the reaction was fast.Third, the kinetics of the degradation process under the optimum reaction conditions at various temperatures was fitted. The results showed the degradation process followed the first order kinetics. The kinetic equation for the optimum reaction temperature is ln C ? ?1.49 t.When under any temperature, the kinetic equation of the reaction under the optimum reaction condition was? ?? ?7ln 3.95 exp 5606.710 MBC ?kt ??? ? ?T t the activation energy was 54.1KJ/mol. The mechanism of the degradation process was discussed, and the hydroxyl radical mechanism was the main mechanism when under the acid condition. According to the experiment, the possible reaction mechanism was presented. Under the basic condition, the mainmechanism was valence iron. It was easy to recycle for the magnetic.In short, the Fe Co Ba oxide nanocrystals prepared in this paper had a wide applied range of p H, when p H was 3.01~11.03, the catalyst not only had a fast reaction rate, but also had a better degradation ability. No needing to add the input UV light, shock, ultrasonic, electric energy,result from the catalyst had a stable performance, it could be reused. Fe Co Ba oxide nanocrystals with many advantages, had a broad practical application prospects in the field of water treatment.