摘要
采用Ce调控负载型钒磷氧(VPO/TiO_2)催化剂的表面酸性并与之形成密切相关的微观结构,研究催化剂VPO-Ce/TiO_2的脱硝性能.结果表明,当P/V为1/3、Ce/V为1/4、活性组分负载量10%、催化剂焙烧温度为400℃时,催化剂的脱硝活性最好,反应温度250～350℃范围内的脱硝率高于96.0%.BET测试结果表明,催化剂0.1VP(0.33)O-Ce(0.25)/TiO_2的比表面积为10.74m^2/g,较0.1VP(0.33)O/TiO2提高了约58.6%.0.1VP(0.33)O/TiO_2表面化学吸附氧(O_α)和晶格氧(O_β)的比例O_α/O_β为72%,掺杂Ce后O_α/O_β升高至85%,Ce掺杂还能促进相邻V^(5+)和V^(4+)的形成,提高催化剂的氧化还原性能.Ce掺杂对催化剂的表面酸性影响较大,当Ce/V为1/4时催化剂表面Br?nsted酸最强,这与活性测试相吻合.控制烟气中SO_2和水蒸气的体积浓度分别为200×10^(-6)和4vol.%,催化剂的脱硝活性在150～300℃温度范围内最高下降约15.8%,当温度高于300℃时催化剂的脱硝活性几乎不下降,且反应后的催化剂表面无硫酸根生成,催化剂呈现出较强的抗SO_2和水蒸汽的性能.
In this paper,the surface acidity and the closely related microstructure of supported vanadium phosphate(VPO/TiO 2)were adjusted by Ce.The denitration performance of VPO-Ce/TiO 2 was also investigated.The results showed that when the P/V was 1/3,the Ce/V 1/4,the loading of active component 10%and the calcination temperature 400℃,the activity of denitrifying catalyst functioned the best with a de-NO x rate above 96%at temperature range of 250~350℃.The BET results showed that the specific surface area of 0.1VP(0.33)O-Ce(0.25)/TiO 2 is 10.74m^2/g and it was 58.6%higher than that of 0.1VP(0.33)O/TiO 2.The mole ratio of chemisorbed oxygen(Oα)and lattice oxygen(Oβ)Oα/Oβof 0.1VP(0.33)O/TiO 2 was 72%and the Oα/Oβincreased to 85%after Ce doping.Moreover,Ce doping could promote the formation of adjacent V^5+and V^4+and improve the redox performance of catalysts.Ce doping had a great effect on the surface acidity of catalyst and the intensity of Bronsted acidity of catalyst was highest when Ce/V is 1/4,which was consistent with the activity test.With 200×10^-6 SO 2 and 4vol.%water vapor in the feed gas,the denitration activity of 0.1VP(0.33)O-Ce(0.25)/TiO 2 dropped by 20%at most at temperature of 150~300℃and it hardly decreased when the temperature was above 300℃.There was no sulfate generated on the 0.1VP(0.33)O-Ce(0.25)/TiO 2 after the activity test and the catalyst showed excellent resistance ability to SO 2 and water vapor.
作者
戴波
张松
顾明言
陈勇
贾勇
史德明
夏勇军
胡笳
DAI Bo;ZHANG Song;GU Ming-yan;CHEN Yong;JIA Yong;SHI De-ming;XIA Yong-jun;Hu Jia(School of Energy andEnviroment,Ahhui University of Technology, Maanshan 243032, China;Key Laboratory of Metallurgical Emission Reduction &Resource Recycling (Ministry of Education), Maanshan 243032, China;Anhui Xinchuang Energy & Environmental ProtectionScience & Techmology Co. Ltd., Maanshan 243071, China)
出处
《中国环境科学》
EI
CAS
CSCD
北大核心
2019年第1期126-133,共8页
China Environmental Science
基金
国家重点研发计划项目(2017YFB0601805)
