摘要
为了提高渗铈活性焦(activated coke,AC)CeO2/AC循环汞脱除效率,研究了其在纯N2条件下热再生时的汞析出规律,发现CeO2/AC再生后释放出的汞形态基本为Hg0,大量汞在270℃左右溢出,少部分在530℃左右溢出,再生温度超过300℃时,其汞再生效率都达到了90%。CeO2/AC的汞脱附特性只与脱附温度有关,而与升温速率关系不大。表面物理结构测定证明了CeO2/AC吸附汞的过程不仅是物理吸附,也存在化学吸附。利用Boehm法和X-射线能谱分析对CeO2/AC表面化学性质检测,发现其二次脱汞效率随再生次数以及再生温度的增加而降低,其原因可以归为活性焦表面的碳在再生过程中受到烧蚀和氧化导致CeO2的损耗以及表面酸性官能团的分解;因此,选择合适的再生温度是保证CeO2/AC循环汞脱除效率的必要条件。
To improve the recycling mercury removal efficiency of the CeO2 impregnated activated coke （AC）, CeO2/AC, the characteristic of mercury desorption was investigated during regeneration process in N2 atmosphere. Most mercury released at about 270℃ and the rest released at about 530℃, in the form of Hg^0. When the regeneration temperature reached 300℃, the mercury regeneration ratio achieved 90%. The characteristic of mercury desorption on CeO2/AC was relevant to the regeneration temperature, but was independent of heating rate. Physical structure data indicated that the mercury adsorption process was a combination of physisorption and chemisorption. Method Boehm and X-ray analysis were used for the chemical properties analysis of CeO2/AC. The results show that the mercury removal efficiency decreas with increasing regeneration times and temperature due to CeO2 loss during the carbon ablation and oxidation as well as desorption of surface acid functional group during the regeneration. Therefore, a suitable regeneration temperature is necessary for the appropriate recycling mercury removal efficiency of CeO2/AC.
出处
《中国电机工程学报》
EI
CSCD
北大核心
2011年第29期61-66,共6页
Proceedings of the CSEE
基金
新世纪优秀人才支持计划项目(NCET-08-0490)
环保公益性行业科研专项经费项目(200909024)~~
关键词
烟气
活性焦
再生
汞脱附
CEO2
flue gas
activated coke
regeneration
mercury desorption
CeO2
