摘要
在固定床反应器上研究了N_2气氛下纳米氧化铁对单质汞的吸附脱除特性,探讨了吸附剂颗粒尺寸,反应床温度,停留时间及表面羟基基团对纳米氧化铁除汞性能的影响。研究表明,与普通氧化铁颗粒瞬间到达穿透相比,纳米氧化铁具有更强的汞吸附能力,相同条件下其80%穿透时间达到45 min,XPS分析表明,纳米氧化铁表面85%以上均为氧化态的汞。汞在纳米氧化铁上的吸附过程中化学反应起重要作用。在试验温度范围内,随着反应床温度增加,纳米氧化铁对汞的吸附性能提高幅度显著。反应前后样品的红外光谱分析结果表明,纳米氧化铁表面主要是游离态的羟基参与了汞吸附反应。
The characteristic of elemental mercury adsorption by nano-ferric oxide was evaluated on a fixed bed reactor in N2 atmosphere. The effects of particle size, temperature, residence time and surface hydroxyl on Hg-removal efficiency were discussed. The result shows that comparing with the immediate breakthrough when using common-size ferric oxide as Hg sorbent, nano-ferric oxide shows excellent Hg adsorption capability, and over 45 minutes for 80% breakthrough time was observed at the same condition. The result by XPS analysis shows that more than 85% of the total mercury on nano-ferric oxide surface is oxidized mercury, which means elemental mercury is mainly chemically adsorbed by the nano-ferric oxide. The increase of bed temperature can promote mercury adsorption, while the result by FTIR analysis shows that dissociative hydroxyl on the surface of nano-sorbent would participate in the reaction for mercury adsorption.
出处
《工程热物理学报》
EI
CAS
CSCD
北大核心
2010年第7期1227-1230,共4页
Journal of Engineering Thermophysics
基金
国家自然科学基金资助项目(No.50525619
No.20677020
No.50721005
No.50706014)
关键词
纳米氧化铁
吸附
单质汞
nano-ferric oxide
adsorption
elemental mercury
