| V2O5/AC在含SO2气氛中对气态Hg0的吸附脱除研究 |
| 摘要点击 2962 全文点击 2767 投稿时间：2009-01-15 修订日期：2009-03-17 |
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| 中文关键词 V2O5/AC SO2 气态Hg0 吸附 脱除 |
| 英文关键词 V2O5/AC SO2 gas-phase Hg0 adsorption removal |
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| 中文摘要 |
| 利用固定床反应器研究了模拟烟气(N2、SO2、O2)气氛下，气态Hg0在V2O5/AC催化剂上的吸附脱除行为.考察了V2O5担载量、SO2浓度和吸附温度等对V2O5/AC吸附脱除Hg0的影响，并对V2O5/AC上吸附汞的形态进行了XPS分析表征.研究发现，V2O5/AC对Hg0的吸附能力远大于载体AC.汞的吸附量与V2O5/AC中V2O5的质量分数有关，随着V2O5质量分数从0.5%增加到1.0%，汞的吸附量从75.9 μg·g-1增加到89.6 μg·g-1 (无氧) 和115.9 μg·g-1增加到185.5 μg·g-1 (有氧)，远高于相同吸附条件下的AC上的汞吸附量 (9.6 μg·g-1和23.3 μg·g-1).SO2对Hg0的吸附有促进作用，主要是由于SO2和Hg0在V2O5/AC上发生了化学反应.但是当SO2体积分数从500×10-6增加到2 000×10-6时，V2O5/AC对汞的吸附量只增加了5%.不同温度下的实验结果表明，V2O5/AC催化剂在150℃左右的吸附脱除Hg0的能力最高，汞的吸附量达到98.5 μg·g-1 (无氧) 和187.7 μg·g-1 (有氧).XPS 分析结果表明，在V2O5/AC催化剂表面有HgO和HgSO4生成，证实了V2O5和SO2的作用. |
| 英文摘要 |
| The adsorption and removal behaviors of gas-phase Hg0 over V2O5/AC and AC were studied under a simulated flue gas (containing N2, SO2, O2) in a fixed-bed reactor. The influences of the V2O5 loading, SO2 concentration and adsorption temperature on Hg0 adsorption were investigated. The speciation of mercury adsorbed was determined by X-ray photoelectron spectroscopy (XPS). It was found that the V2O5/AC catalyst has a much higher capability than AC for Hg0 adsorption and removal, mainly because of the catalytic oxidation activity of V2O5. The Hg0 adsorption capability depends on the V2O5 content of the V2O5/AC catalyst. The amounts of mercury adsorbed increase from 75.9 μg·g-1 to 89.6 μg·g-1 (in the absence of O2) and from 115.9 μg·g-1 to 185.5 μg·g-1 (in the presence of O2) as the V2O5 loading increases from 0.5% to 1.0%，which are much higher than those over AC under the same conditions (9.6 μg·g-1 and 23.3 μg·g-1). SO2 in the flue gas enhances Hg0 adsorption over the V2O5/AC catalyst, which is due to the reaction of SO2 and Hg0 on V2O5/AC. But as the SO2 concentration increases from 500×10-6 to 2 000×10-6, the amount of mercury adsorbed has only a slight increase. The optimal temperature for Hg0 adsorption over the V2O5/AC catalyst is around 150℃, at which the amounts of mercury adsorbed are up to 98.5 μg·g-1 (in the absence of O2) and 187.7 μg·g-1 (in the presence of O2). The XPS results indicate the formation of HgO and HgSO4 on the surface of the V2O5/AC catalyst, which confirms the role of V2O5 and SO2. |
