摘要
利用石英固定床反应器 ,进行了氧气对半焦还原 NO的实验 .结果表明 ,氧气对于半焦 -NO反应有显著的促进作用 ;低温下氧气对半焦 - NO反应的促进作用随温度升高而增加 ,但高温下 O2 的促进作用随温度的升高趋于下降 ;此外 ,氧气的促进作用在某一浓度范围内随其浓度的增大而增加 ,但超过这范围 ,其促进作用随浓度增加反而下降 .半焦的预氧化可显著增加半焦的反应性 ,高温热处理预氧化的半焦可使其丧失较高的反应性 .氧气对半焦还原 NO的促进作用是通过氧化半焦并在半焦表面上形成活性位 ( C( O) )
The effect of O2 on NO-char reaction was investigated in a quartz fixed-bed at the atmospheric pressure. The results show that the O2 can significantly promote the NO-char reaction even at a very low concentration (0.2%). Two temperature regimes are found for the NO-char reaction in both the absence and presence of O2. The promotion of O2 increases with the rise of temperature first, then decreases because of the remarkable desorption of C (O) at a high temperature. The activity of char can be increased remarkably by pre-oxidization; While if the pre-oxidized char is pretreated at 950°C, the activity of the char will decrease to the same level of the original char. The discussion about the promotion mechanism of O2 on NO-char reaction also shows that the promotion of NO-char reaction is realized by forming a carbon-oxygen complex (C(O)) on the char surface.
出处
《中国矿业大学学报》
EI
CAS
CSCD
北大核心
2001年第5期484-487,491,共5页
Journal of China University of Mining & Technology
基金
国家自然科学基金资助项目 ( 2 9876 0 47)
国家自然科学基金重点资助项目 ( 2 9936 0 90 )
关键词
氧气
煤焦
NO
还原
一氧化氮
半焦
燃煤
Air pollution
Coal combustion
Oxygen
Reaction kinetics
Reduction
