摘要
利用管式炉对活性碳纤维进行汞吸附性能试验.实验发现:在气体汞浓度为5263.5μg·m-3,吸附温度90℃,气体停留时间0.1s时,筒式吸附体在前20min内吸附汞效率在80%以上,吸附180min后吸附汞效率仍在20%左右.随着吸附温度的升高汞吸附效率先增加后降低,停留时间的延长和H2O(g)的存在均有利于汞的吸附.采用热重分析法(TGA)对汞饱和活性碳纤维进行热脱附研究,结果表明,汞的脱附发生在100℃—230℃范围内,在40min内从50℃升温至350℃,汞脱附率为69.93%.汞饱和活性碳纤维热脱附后的扫描电镜分析表明:物理吸附的汞易于脱附,氧化汞难以脱附,同时在热脱附过程中存在单质汞向氧化汞的转化.
In this work the attention was focused on the adsorption and desorption of elemental mercury on activated carbon fibre. Test results showed that the adsorption efficiency of mercury was above 80% in the first 20 minutes and still as high as around 20% after 180 minutes with mercury concentration 5263.5μg ·m-3 in the nitrogen stream, and retention time 0. 1s, at adsorption temperature 90℃. When increasing adsorption temperature, the adsorption efficiency first increased from 70℃ to 90℃, but decreased from 90℃ to 140℃. Both the increment of retention time and existence of water steam could promote mercury adsorption. The thermal desorption process was studied by thermogravimetric analysis （TGA） . Results indicated that mercury desorption from activated carbon fibre occurred in the temperature range from 100℃ to 230℃, and mercury desorption efficiency was 69.93% as temperature increased from 50℃ to 350℃ within 40 minutes. The SEM micrograph of activated carbon fibre saturated with mercury after thermal desorption showed that elemental mercury disappeared but mercuric oxide particles got more and bigger. It suggested that elemental mercury can be easily removed by thermal treatment but mercuric oxide can＇t, and part of elemental mercury may transform to mercuric oxide during thermal desorption run.
出处
《环境化学》
CAS
CSCD
北大核心
2008年第5期605-609,共5页
Environmental Chemistry
基金
浙江省"151"人才工程
浙江省新苗人才计划(2007G60G2070039)资助项目
关键词
活性碳纤维
气态汞
吸附
脱附
activated carbon fibre, gaseous mercury, adsorption, desorption.
