Key Laboratory for Energy Thermal Conversion and Control, Ministry of Education, Southeast University, Nanjing 210096, China.
Key Laboratory for Energy Thermal Conversion and Control, Ministry of Education, Southeast University, Nanjing 210096, China.
J Environ Sci (China). 2020 May;91:279-291. doi: 10.1016/j.jes.2020.01.011. Epub 2020 Jan 25.
The deposition of NHHSO and the poisoning effect of SO on SCR catalyst are the main obstacles that restrict the industrial application of CeO-doped SCR catalysts. In this work, deposited NHHSO decomposition behavior and SO poisoning over VO-MoO/TiO catalysts modified with CeO and SiO were investigated. By the means of characterization analysis, it was found that the addition of SiO into VMo/Ti-Ce had an impact on the interaction existed between catalyst surface atoms and NHHSO. Temperature-programmed methods and in situ diffused reflectance infrared Fourier transform spectroscopy (DRIFTS) experiments indicated that the doping of SiO promoted the decomposition of deposited NHHSO on VMo/Ti-Ce catalyst surface by reducing the thermal stability of NHHSO and enhancing the NHHSO reactivity with NO in low temperature. And this improvement may be the reason for the better catalytic activity than VMo/Ti-Ce in the case of NHHSO deposition. Accompanied with cerium sulfate species generated over catalyst surface, the conversion of SO to SO was inhibited in SiCe mixed catalyst. The addition of SiO could promote the decomposition of cerium sulfate, which may be a potential strategy to enhance the resistance of SO poisoning over CeO-modifed catalysts.
NHHSO 的沉积和 SO 对 SCR 催化剂的毒害作用是限制 CeO 掺杂 SCR 催化剂工业应用的主要障碍。本工作考察了 CeO 和 SiO 改性的 VO-MoO/TiO 催化剂上沉积的 NHHSO 分解行为和 SO 中毒。通过表征分析发现，SiO 的加入对催化剂表面原子与 NHHSO 之间的相互作用有影响。程序升温法和原位漫反射红外傅里叶变换光谱（DRIFTS）实验表明，SiO 的掺杂通过降低 NHHSO 的热稳定性和增强 NHHSO 在低温下与 NO 的反应性，促进了 VMo/Ti-Ce 催化剂表面沉积的 NHHSO 的分解。这种改进可能是在 NHHSO 沉积的情况下，SiCe 混合催化剂比 VMo/Ti-Ce 具有更好催化活性的原因。在催化剂表面生成硫酸铈物种的同时，SO 向 SO 的转化率受到抑制。SiO 的加入可以促进硫酸铈的分解，这可能是增强 CeO 改性催化剂抗 SO 中毒的一种潜在策略。
