摘要
为改善更高温度下稀土氧化物Y_(2)O_(3)直接分解NO的性能,在管式炉中实验考察了混合BaO和ZrO_(2)两种金属氧化物对NO分解效率的影响。结果显示,混合BaO和ZrO_(2)可以改善Y_(2)O_(3)直接分解NO的活性,其中质量比为0.233/1/9的ZrO_(2)/BaO/Y_(2)O_(3)混合催化剂的效果最好,在1473 K、NO/Ar气氛下NO分解效率可达93%。当气氛中存在CO_(2)和O_(2)时,尽管温度窗口内催化剂直接分解NO的活性降低,但1473 K时的分解效率仍可以维持45%以上。气氛中CO的共存能降低催化剂活化温度并协同实现NO完全分解。X射线衍射测试表明ZrO_(2)/BaO/Y_(2)O_(3)在高温下发生固溶,Zr^(4+)的掺杂使Y_(2)O_(3)晶格常数变小,生成了更适合NO吸附和分解的活性氧空位。本研究表明多种金属氧化物机械混合后高温煅烧是一种有前景的NO直接分解催化剂的制备方法。
In order to improve the NO direct decomposition of rare earth oxide Y_(2)O_(3) under high temperatures,the effects of BaO and ZrO_(2) mixing on the NO conversion efficiency were investigated in a tubular furnace.The results show that mixing Y_(2)O_(3) with BaO and ZrO_(2) can increase the NO direct decomposition activity and the best mass ratio of ZrO_(2)/BaO/Y_(2)O_(3) is 0.233/1/9,which can show a high NO conversion efficiency of 93%at 1473 K under NO/Ar atmosphere.In the presence of CO_(2) and O_(2),although the activity of NO decomposition decreases in the temperature window,the NO conversion efficiency can still maintain above 45%at 1473 K.The coexistence of CO can lower the activation temperature of the catalyst and synergistically promote the complete decomposition of NO.The X-ray diffraction results show the formation of ZrO_(2)/BaO/Y_(2)O_(3) solid solution at high temperature,in which Zr^(4+) doping makes the lattice constant of Y_(2)O_(3) smaller,resulting in active oxygen vacancies more suitable for NO adsorption and decomposition.These results suggest that mechanical mixing of various metal oxides followed by high temperature calcination is a promising method to prepare catalysts for NO direct decomposition.
作者
杨浩林
张剑桥
曾小军
李凡
汪小憨
YANG Haolin;ZHANG Jianqiao;ZENG Xiaojun;LI Fan;WANG Xiaohan(Guangzhou Institute of Energy Conversion,Chinese Academy of Sciences,Guangzhou,510640,China;Key Laboratory of Renewable Energy,Chinese Academy of Sciences,Guangzhou,510640,China;Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development,Guangzhou,510640,China;Nano Science and Technology Institute,University of Science and Technology of China,Suzhou,215000,China)
出处
《环境化学》
CAS
CSCD
北大核心
2022年第7期2397-2403,共7页
Environmental Chemistry
基金
广州市科技计划项目(201903010019)
广东省重点领域研发计划项目(2020B1111360004)资助。
关键词
稀土氧化物
氧化钇
NO
直接分解
rare earth oxide
yttrium oxide
NO
direct decomposition
