Elemental mercury catalytic oxidation removal and SeO2 poisoning investigation over RuO2 modified Ce-Zr complex
Elemental mercury catalytic oxidation removal and SeO2 poisoning investigation over RuO2 modified Ce-Zr complex
复制标题
RuO2 修饰 Ce-Zr 络合物催化氧化去除单质汞及 SeO2 中毒研究
DOI：
10.1016/j.apcata.2018.07.022
复制
发表时间：
2018
期刊：
影响因子：
--
通讯作者：
Yan Naiqiang
中科院分区：
文献类型：
--
作者：
Zhao Songjian;Chen Wanmiao;Huang Wenjun;Xie Jiangkun;Qu Zan;Yan Naiqiang
燃煤烟气中的汞排放引起了全世界的广泛关注。为了实现Hg0在高温和低温下更有效的催化氧化，制备了RuO2修饰的Ce-Zr固溶体催化剂，并在不同条件下进行了评价。研究发现聚乙烯吡咯烷酮（PVP）促进的RuO2/Ce0.6Zr0.4O2催化剂对Hg0氧化表现出更高的显着催化活性。通过多种技术研究了RuO2/Ce0.6Zr0.4O2(PVP)上Hg0氧化的机理，发现Hg0氧化途径包括两个步骤：化学吸附过程和再生过程。吸附的 Hg0 首先被表面化学吸附的氧物质氧化形成 HgO，HgO 在没有 HCl 的情况下可以自行从催化剂表面解吸。此外，HgO 可以与催化剂中的 Cl− 或吸附的 HCl 反应形成 HgCl2，从而更容易解吸到气相中。 O2对于化学吸附过程是不可缺少的。并且掺杂的RuO2可能与载体具有协同作用，从而促进化学吸附过程。此外，首次对催化剂的SeO2中毒进行了研究，发现SeO2的存在会轻微抑制Hg0在催化剂表面的化学吸附过程，而对再生过程没有显着影响。
The mercury emission from coal-fired flue gas has drawn lots of attention worldwide. To achieve more efficient catalytic oxidation of Hg0in both high and low temperature, the RuO2modified Ce-Zr solid solution catalysts were prepared and evaluated at various conditions. It was found the polyvinylpyrrolidone (PVP) promoted RuO2/Ce0.6Zr0.4O2catalyst displayed higher significant catalytic activity for Hg0oxidation. The mechanism of Hg0oxidation over RuO2/Ce0.6Zr0.4O2(PVP) was studied through various techniques, and Hg0oxidation approaches were found to consist of two steps: chemisorption process and regeneration process. The adsorbed Hg0was first oxidized with surface chemisorbed oxygen species to form HgO, which could desorb from the surface of catalysts by itself in absence of HCl. Also, the HgO could reacts with Cl−in catalyst or adsorbed HCl to form HgCl2, which could desorb into gas phase more readily. O2is indispensable for the chemisorption process. And the doping RuO2might have a synergistic effect with supporter, which could facilitate chemisorption process. Furthermore, SeO2poisoning of catalyst was investigated for the first time and found the existence of SeO2could slightly inhibit Hg0chemical adsorption process on the surface of the catalyst, while the regeneration process did not significantly affect.