采用程序升温脱附、X射线光电子能谱、元素分析和原位漫反射傅里叶变换红外光谱等方法研究了V2O5/AC同时脱硫脱硝催化-吸附剂在5%NH3-95%Ar气氛下再生时的碳烧蚀行为和机理.结果表明,NH3与V2O5/AC表面的含氧组分(羧基、羟基、酚羟基以及V2O5等)发生了作用,优先消耗了V2O5/AC表面上的氧,生成了H2O和多种表面含氮官能团((内)酰胺类和腈类等),从而抑制了再生时碳的烧蚀.
The activated carbon (AC)-supported V2O5 catalyst-sorbent, V2O5/AC, was found to be very effective for the simultaneous removal of SO2 and NO from flue gas at 200 ℃. The catalyst-sorbent, however, may suffer from high carbon loss during periodical regeneration required by the SO2 removal process. The SO2-adsorbed V2O5/AC catalyst-sorbent could be regenerated in the presence of NH3 at low temperature (300 ℃ ), and the carbon burn-off is much less than that in an inert atmosphere. In this study, the behaviors and mechanism of carbon burn-off during the regeneration of V2O5/AC in 5 % NH3-95 % Ar were studied using temperature-programmed desorption, elemental analysis, X-ray photoelectron spectroscopy, and Fourier transform infrared spectroscopy. The carbon consumption amount for the regeneration carried out in 5 % NH3-95 % Ar is much lower than that in Ar atmosphere. The presence of NH3 inhibits the carbon burn-off by reacting with the surface oxygen-containing groups in V2O5/AC, -COOH, -OH, and V2O5 etc, to produce H2O and nitrogen-containing groups such as -CONH2, C-N, and C≡N.