THE ACTIVE SITES AND PERFORMANCE OF Mn1Cex/HZSM-5 CATALYST FOR FORMALDEHYDE REMOVAL AT ROOM TEMPERATURE
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摘要: 装修等产生的室内甲醛严重影响人体健康,因此在室温下降解甲醛的需求日益迫切。目前,常温催化氧化法被视为最有前景的甲醛处理方法之一。沸石分子筛具有较大比表面积及较多吸附位点,以此为载体,以MnOx和CeOx为反应活性位点,通过共沉淀法成功合成了Mn1Cex/HZSM-5催化剂。该催化剂在常温下可降解96.86%的甲醛且具有良好的稳定性。此外,通过一系列的物理化学表征分析发现,Ce物种不仅能够显著提高催化剂中高价态锰的含量,还能带来更多的表面吸附羟基和吸附氧,进而提升催化剂的性能。鉴于其优异及稳定的性能、简便的合成方法,此高效除甲醛Mn1Cex/HZSM-5催化剂可为室温下除甲醛催化剂的合成提供新的参考。Abstract: Formaldehyde caused by indoor decoration has serious impact on human health, the need to reduce formaldehyde at room temperature is increasingly urgent. At present, room temperature catalytic oxidation is regarded as one of the most promising formaldehyde treatment methods. Zeolite molecular sieve has a large specific surface area and more adsorption sites. In this paper, with zeolite molecular sieve as the carrier, and MnOx and CeOx as reaction active sites, Mn1Cex/HZSM-5 catalyst was successfully synthesized through co-precipitation method. The catalyst degraded 96.86% of formaldehyde at room temperature and had good working stability. In addition, through a series of physical and chemical characterization analysis, it was found that Ce species could not only significantly improve the content of high-valent manganese in the catalyst, but also bring more surface hydroxyl and oxygen adsorption, thus improving the performance of the catalyst. In view of its excellent and stable performance and simple synthesis method, this highly efficient formaldehyde removal catalyst, Mn1Cex/HZSM-5 could provide a novel reference for the synthesis of formaldehyde removal catalyst at room temperature.
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Key words:
- molecular sieve /
- catalytic oxidation /
- bimetal catalyst /
- indoor air pollution
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