Department of Environmental Engineering, Zhejiang University, Hangzhou 310027, China.
J Colloid Interface Sci. 2010 Dec 1;352(1):143-8. doi: 10.1016/j.jcis.2010.08.031. Epub 2010 Aug 13.
A series of MnO(x)/TiO(2) composite nanoxides were prepared by deposition-precipitation (DP) method, and the sample with the Mn/Ti ratio of 0.3 showed a superior activity for NO catalytic oxidation to NO(2). The maximum NO conversion over MnO(x)(0.3)/TiO(2)(DP) could reach 89% at 250°C with a GHSV of 25,000h(-1), which was much higher than that over the catalyst prepared by conventional wet-impregnation (WI) method (69% at 330°C). Characterization results including XRD, HRTEM, FTIR, XPS, H(2)-TPR, NO-TPD and Nitrogen adsorption-desorption implied that the higher activity of MnO(x)(0.3)/TiO(2)(DP) could be attributed to the enrichment of well-dispersed MnO(x) on the surface and the abundance of Mn(3+) species. Furthermore, DRIFT investigations and long-time running test indicated that NO(2) came from the decomposition of adsorbed nitrogen-containing species.
一系列的 MnO(x)/TiO(2) 复合纳米氧化物通过沉淀法制备，其中 Mn/Ti 比为 0.3 的样品对 NO 催化氧化为 NO(2)表现出更高的活性。在 GHSV 为 25000h(-1)、温度为 250°C 的条件下，MnO(x)(0.3)/TiO(2)(DP) 的最大 NO 转化率可达 89%，明显高于传统浸渍法（WI）制备的催化剂（330°C 时的转化率为 69%）。包括 XRD、HRTEM、FTIR、XPS、H(2)-TPR、NO-TPD 和氮气吸附-脱附等表征结果表明，MnO(x)(0.3)/TiO(2)(DP) 的高活性可归因于表面上分散良好的 MnO(x)的富集和丰富的 Mn(3+)物种。此外，DRIFT 研究和长时间运行测试表明，NO(2)来自吸附的含氮物种的分解。
