科研之友
微信
新浪微博
Facebook
分享链接
摘要
The Co-Mn/Ti-Ce catalyst prepared by sol-gel and impregnation method was evaluated for catalytic oxidation of Hg-0 in the simulated flue gas compared with Co/TiO2 and Co-Mn/TiO2. The results showed that Co-Mn/Ti-Ce catalyst exhibited higher catalytic activity (around 93% Hg-0 removal efficiency in the temperature of 150 A degrees C with 6% O-2, 400 ppm NO, 200 ppm SO2 and 3% H2O) than Co/TiO2 and Co-Mn/TiO2. Based on the characterization results of N-2 adsorption-desorption, XRD, UV-Vis, XPS, H-2-TPR and Hg-TPD, it could be concluded that the lower band gap, better reducibility and mercury adsorption capability and the presence of Co3+/Co2+, Mn4+/Mn3+ and Ce4+/Ce3+ redox couples as well as surface oxygen species contributed to the excellent Hg-0 oxidation removal performance. In addition, well dispersion of active components and a synergetic effect among Co, Mn and Ce species might improve the activity further. A Mars-Maessen mechanism is thought to be involved in the Hg-0 oxidation. The lattice oxygen derived from MnO (x) or CoO (x) would react with adsorbed Hg-0 to form HgO and the consumption of lattice oxygen could be replenished by O-2. For Co-Mn/Ti-Ce, MnO (x-1) could be alternatively reoxidized by the lattice oxygen derived from adjacent CoO (x) and CeO (x) which is beneficial to the Hg-0 oxidation.
- 出版日期2017-9
- 单位南方电网科学研究院有限责任公司; 武汉大学
