烟气中NO分子对碳基吸附单质铅的影响机理  

Effect of Nitric Oxide in Flue Gas on Elemental Lead Adsorption over Carbonaceous Surface

作　　者：余岳溪 冯永新 廖永进 杨维结 高正阳[2] 

机构地区：[1]广东电网有限责任公司电力科学研究院,广州510080 [2]华北电力大学能源动力与机械工程学院,河北保定071003

出　　处：《动力工程学报》2017年第1期39-44,65,共7页Journal of Chinese Society of Power Engineering

基　　金：南方电网科研基金资助项目(K-GD2014-173)

摘　　要：采用量子化学密度泛函理论中B3PW91和B2PLYP方法,研究了NO分子对碳基吸附单质铅的影响.选定五环锯齿形苯环簇为碳基表面模型,在不同活性位点进行结构优化计算,得到2种NO分子在碳基表面的吸附构型、4种单质铅在含NO分子的碳基表面的吸附构型.计算并分析了键长、键级、电荷以及吸附能等重要参数.结果表明:NO分子比单质铅更容易吸附在碳基表面,会与单质铅竞争碳基表面的活性位;NO分子的加入会显著增强碳基表面对单质铅的吸附作用,吸附性能的提升主要缘于NO分子提高了其邻位活性位点的活性,而不是NO分子直接吸附单质铅;键级与吸附能呈现正相关趋势,键级越大,对应构型的吸附能也越大;Pb原子所带电荷量与吸附能呈明显的线性关系,Pb原子所带电荷量越多,对应吸附构型的吸附能越大.The effect of nitric oxide in flue gas on lead adsorption over carbonaceous surface was investigated by the methods of B3PW91 and B2PLYP in density functional theory of quantum chemistry. The benzene cluster with five zigzag rings was selected as the carbonaceous surface model, based on which structural optimization was carried out at different active sites, so as to obtain two configurations of NO adsoprtion on carbonaceous surface and four configurations of elematal lead adsoprtion on carbonaceous surface containing NO molecules. Meanwhile, main parameters, such as bond length, bond order, charge and adsorption energy were calculated and analyzed. Results indicate that NO molecule is more likely to be adsorpted by carbonaceous surface than elemental lead, and it competes with elemental lead for active sites on the carbonaceous surface. NO molecule could significantly enhance the adsorption of elemental lead on carbonaceous surface, and the enhancement of adsorption capacity is mainly due to further activation of ortho active sites, but not direct adsorption of elemental lead by NO molecule. Bond order exhibits a positive correlation with adsorption energy; the higher the bond order, the greater the adsorption energy of corresponding configuration. An apparent linear correlation the adsorption energy; the more electric charge on Pb exists between the atom, the greater electric charge the adsoprtion sponding configuration.

关 键 词：NO 碳基 单质铅 吸附 量子化学 

分 类 号：X701[环境科学与工程—环境工程]