【作者】 赵玉；

【导师】 王虹； 潘利祥；

【作者基本信息】 北京石油化工学院 ， 化学工程（专业学位）， 2021， 硕士

【摘要】 氧化亚氮（N₂O）是一种具有高增温潜值的温室气体,破坏臭氧层,危害人体健康。在现有研究去除N₂O的方法中,直接催化分解N₂O是最经济、有效的减排技术。本论文分别采用浸渍法和溶剂热法制备M/分子筛催化剂和铋系氧化物催化剂,分别用于热催化分解N₂O和光催化分解N₂O,通过XRD、SEM、BET、H₂-TPR、NH₃-TPD、Py-IR、O₂-TPD、FTIR、UV-vis DRS、PL等手段对催化剂的理化性质进行表征。研究结果显示:1、Co/zeolite催化剂催化分解N₂O性能分子筛载体种类和Co负载量均影响Co（x）/zeolite催化剂催化性能,其中,以Hβ为载体、Co负载量为2.5%的Co（2.5）/Hβ催化剂催化分解N₂O性能较好,N₂O分解温度低,T₁₀、T₅₀和T₉₀分别为336、383和430℃。Co（2.5）/Hβ催化剂中添加Fe、Ni、Cu或Mg助剂未能改善催化剂分解N₂O活性,甚至使N₂O分解温度升高;添加Ca、Sr或Ba可不同程度降低催化剂催化分解N₂O温度,其中Sr为助剂,添加量为0.5%,即Sr（0.50）Co（2.5）/Hβ催化剂催化分解N₂O活性较好,N₂O分解温度低,T₁₀、T₅₀和T₉₀分别为316、371和418℃。2、Cu/HZSM-5催化剂催化分解N₂O性能HZSM-5分子筛硅铝比和Cu负载量均影响Cu/HZSM-5催化剂反应活性,硅铝比为81,Cu负载量为2.0%,即Cu（2.0）/HZSM-5（81）催化剂催化分解N₂O性能较好,N₂O分解温度低,T₁₀、T₅₀和T₉₀分别为392、452和486℃。Cu（1）/HZSM-5（81）催化剂中Mg、Ca或Sr助剂,催化剂的活性均未得到改善,以Ba为助剂,添加量为0.25,即Ba（0.25）Cu（1）/HZSM-5催化分解N₂O性能较好,T₁₀、T₅₀和T₉₀分别为395、445和480℃。3、铋系氧化物催化剂光催化分解N₂O性能溶剂热法制备铋系氧化物催化剂,晶化温度和催化剂组成影响催化剂光催化分解N₂O性能,晶化温度为160℃,光照时间低于10 h,Bi₂Mo O₆光催化性能较好,但光照时间达到12 h,Bi Fe O₃光催化性能略好,N₂O转化率为12.2%。更多还原

【Abstract】 Nitrogen monoxide（N₂O）is a greenhouse gas with high warming potential,which destroys ozone in the atmospheric stratosphere and endangers human health.Among current methods to remove N₂O,direct catalytic decomposition of N₂O is the most economic and effective emission reduction technology.In this paper,metal catalysts supported on zeolites（M/zeolites）and bismuth-based photocatalysts were prepared by impregnation method and solvothermal method,respectively.The catalysts were characterized by XRD,SEM,BET,H₂-TPR,NH₃-TPD,Py-IR,O₂-TPD,FTIR,UV-vis DRS and PL.The catalytic decomposition of N₂O was evaluated in a fixed-bed microreactor or a photocatalytic reactor.The results show that:1.Effect of Co/zeolite catalysts on N₂O catalytic decompositionThe type of zeolite support and Co loading amount affected the catalytic performance of Co（x）/zeolites catalysts.The results indicared that the Co（2.5）/Hβcatalyst,which the zeolite support was Hβand the Co loading was 2.5 wt%,displayed better catalytic activity with low decomposition temperature of N₂O.The temperatures of 10%,50%,90%N₂O conversion(T₁₀,T₅₀ and T₉₀)are 336,383 and 430°C,respectively.The addition of Fe,Ni,Cu or Mg in Co（2.5）/Hβcatalyst did not improve the activity of N₂O decomposition but increased the decomposition temperature of N₂O.The addition of Ca,Sr or Ba can reduce the catalytic decomposition temperature of N₂O to varying degrees,and the addition of Sr have the best performance.The Sr（0.50）Co（2.5）/Hβcatalyst exhibited good catalytic activity for N₂O decomposition,and the decomposition temperature of N₂O is low.The T₁₀,T₅₀ and T₉₀ are 316,371 and 418°C,respectively.2.Effect of Cu/HZSM-5 catalysts on N₂O catalytic decompositionThe silicon-aluminum（Si/Al）ratio of zeolites and the Cu loading amount affected the catalytic performance of Cu/HZSM-5 catalyst.The results showed that the Cu（2.0）/HZSM-5（81）catalyst,which the Si/Al ratio was 81 and Cu loading was 2.0 wt%,displayed better catalytic activity with low decomposition temperature of N₂O.The T₁₀,T₅₀ and T₉₀are 392,452 and 486°C,respectively.The addition of Mg Ca,or Sr could not improve the activity of N₂O decomposition but increased the decomposition temperature.The addition of Ba promoters improved the catalytic decomposition of N₂O to varying degrees.When the addition amount of Ba was 0.25 wt%,the catalytic activity of the Ba（0.25）Cu（1）/HZSM-5 catalyst was better.The T₁₀,T₅₀and T₉₀ were 395,445 and 481°C,respectively.3.Effect of bismuth-based photocatalysts on N₂O catalytic decompositionBismuth photocatalysts prepared by solvothermal method showed significant photocatalytic activity.The crystallization temperature and catalyst composition affected the photocatalytic decomposition activity.The results showed Bi₂Mo O₆ prepared with the crystallization temperature of 160°C showed had better photocatalytic activity,displayed better photocatalytic activity When the illumination time was less than 10 h,the performance of Bi Fe O₃ catalyst was good when the irradiation time reached 12 h,and the conversion rate of N₂O was 12.2%,respectively.更多还原