摘要
抗硫性能是评价脱硝过程中催化剂性能的关键指标,研究SO2对催化剂理化特性的影响对催化剂脱硝应用具有重要意义。通过焙烧处理白云鄂博稀土精矿得到稀土精矿催化剂,利用催化剂抗硫性能实验台,结合SEM、BET、XRD和FT-IR,分析了O2、NH3、NO气氛下SO2在催化剂表面的吸附及不同SO2浓度对催化剂催化脱硝性能的影响。结果表明,SO2对稀土精矿催化剂脱硝性能有显著的促进作用,300℃时,NO转化率从28%提高至50%,350℃时,NO转化率从42%提高至75%;SEM、BET和XRD结果表明催化剂抗硫性能测试前后的物理结构和化学组成基本保持不变,稀土精矿催化剂具有较好的抗硫性能;FT-IR结果证实SO2的吸附使稀土精矿催化剂表面B酸性位点增多,催化剂对NH3的吸附能力增强,因此有利于提高催化剂活性。研究结果可为白云鄂博稀土精矿催化剂NH3-SCR脱硝应用过程中抗硫性能提供有价值的基础数据参考。
Sulfur resistance is a key indicator for evaluating catalyst performance during denitration.It is important to study the effect of SO2 on the physicochemical properties of catalysts.The rare earth concentrate catalyst was obtained by roasting the Bayan Obo rare earth concentrate.Using the sulfur resistance test bed of the catalyst and combining scanning electron microscope(SEM),Brunner Emmett Teller(BET),X-ray diffraction(XRD)and in situ Fourier transform infrared spectroscopy(FT-IR),the adsorption of SO2 on the catalyst surface under the atmosphere of O2,NH3 and NO,as well as the influence of different SO2 concentrations on catalytic denitrification were analyzed.The results show that SO2 can significantly promote the denitrification performance of rare earth concentrate catalysts.The NO conversion rate increased from 28%to 50%at 300℃and increased from 42%to 75%at 350℃.SEM,BET and XRD results illustrated that the surface structure and chemical composition of the catalyst remain unchanged before and after denitrification.The rare earth concentrate had good sulfur resistance.The FT-IR results verified that the adsorption of SO2 increased B acid sites on the surface of the rare earth concentrate catalyst.The adsorption capacity of the catalyst for NH3 was enhanced,contributing to increase catalyst activity.The results can provide valuable basic data reference for the anti-sulfur performance of the Bayan Obo rare earth concentrate catalyst NH3-SCR denitrification application process.
作者
焦坤灵
赵阳国
武文斐
王振峰
龚志军
JIAO Kunling;ZHAO Yangguo;WU Wenfei;WANG Zhenfeng;GONG Zhijun(School of Energy and Environment,Inner Mongolia University of Science and Technology,Baotou 014010,Inner Mongolia,China;Key Laboratory of Integrated Exploitation of Bayan Obo Multi-Metal Resources,Baotou 014010,Inner Mongolia,China)
出处
《化工学报》
EI
CAS
CSCD
北大核心
2019年第12期4645-4653,共9页
CIESC Journal
基金
国家自然科学基金项目(51866013)
内蒙古自治区自然科学基金项目(2017MSLH0529)