Department of Chemical and Biological Engineering, Korea University, 5-1, Anam-dong, Sungbuk-ku, Seoul 136-713, Republic of Korea.
J Hazard Mater. 2012 Oct 30;237-238:153-60. doi: 10.1016/j.jhazmat.2012.08.026. Epub 2012 Aug 19.
In this study, Pt/Fe/ZSM5 catalysts were applied to oxidation of ammonia, where the catalysts showed good low-temperature activity (≤ 200°C) for converting ammonia into nitrogen. With 1.5% Pt/0.5% Fe/ZSM5 catalyst, we could obtain 81% NH(3) conversion and 93% N(2) selectivity at 175°C at the short contact-time of w/f=0.00012 g min/mL. Through the characterization studies using high-resolution transmission electron microscopy (HRTEM) and X-ray spectroscopies (XRD, XPS), we could find that the active species was collaborating Pt/Fe species, which structure and activity were largely influenced by support material - in a positive way by ZSM5, rather than by Al(2)O(3) and SiO(2). When using ZSM5 as the support material, Pt was highly dispersed exclusively on the Fe oxide, and the valence state and dispersion of Pt changed according to Fe loading amount.
在这项研究中，Pt/Fe/ZSM5 催化剂被应用于氨氧化反应中，该催化剂在将氨转化为氮气方面表现出良好的低温活性（≤200°C）。在 175°C 时，使用 1.5%Pt/0.5%Fe/ZSM5 催化剂，在 w/f=0.00012 g min/mL 的短接触时间下，可以获得 81%的 NH(3)转化率和 93%的 N(2)选择性。通过使用高分辨率透射电子显微镜（HRTEM）和 X 射线能谱（XRD、XPS）进行的表征研究，我们可以发现活性物质是协同的 Pt/Fe 物种，其结构和活性在很大程度上受到载体材料的影响——ZSM5 以积极的方式影响，而不是 Al(2)O(3)和 SiO(2)。当使用 ZSM5 作为载体材料时，Pt 高度分散在 Fe 氧化物上，Pt 的价态和分散度根据 Fe 负载量而变化。
