| dc.description.abstract | Formaldehyde (HCHO) is a common indoor air pollutant. Long-term exposure to HCHO causes allergic, teratogenic, and carcinogenic effects. Among the methods for removing HCHO, ozone catalytic oxidation (OZCO) is an economical and efficient method, which oxidizes HCHO to CO2 and H2O through the strong oxidizing radical when the ozone is decomposed on catalysts. However, ozone is also an air pollutant, even low concentrations of ozone will react with organic matter in the air to produce adverse effects, which will seriously harm the human body and the environment. Therefore, the key issues in the research of OZCO of HCHO are identified and development of catalyst that completely decompose ozone and HCHO at room temperatures is essential. Among them, the manganese-based oxide catalyst has received extensive attention from researchers due to its relatively low price and excellent performance. In this study, modification of manganese-based catalysts was carried out and MnCeNiOx was prepared by doping transition metals (Ce, Ni) during the sol-gel synthesis process. By optimizing the doping ratio, it is found that the catalyst activity is the best when the ratio of Mn:Ce:Ni is 1. The FeOx prepared by the co-precipitation method is used to modify the catalyst to further enhance the catalytic activity for HCHO removal. The results show that FeOx-MnCeNiOx has a 100% conversion efficiency for 1,000 ppm ozone at room temperature and a relative humidity of 90%. Complete oxidation of 15 ppm HCHO to CO2 and H2O(g) is achieved at 100℃. As 45 ppm of ozone is added at room temperature, the HCHO conversion rate reached 95%, and the stability of its catalytic effect is ensured in the 72 hr long-period test. At the same time, BET, XRD, XPS and other characterization methods proved the beneficial effect of the synergy among various metals in the FeOx-MnCeNiOx catalyst on the conversion of ozone-catalyzed oxidation of HCHO. Meanwhile, the reaction mechanism of ozone-catalyzed oxidation of HCHO is proposed. In summary, this study prepared a new type of catalyst with high catalytic activity and stability for low-concentration HCHO removal at room temperature, and this catalyst has good practical application prospects. | en_US |