应用量子化学计算研究燃煤烟气中氟与汞的反应动力学  

Kinetic Parameter of Reactions Between Mercury and Fluorine Compounds

作　　者：殷立宝[1] 周黎明[2] 徐齐胜[1] 于航[2] 陈传敏[3] 

机构地区：[1]广东电网公司电力科学研究院,广州510000 [2]华北电力大学能源与动力工程学院,保定071003 [3]华北电力大学环境科学与工程学院,保定071003

出　　处：《燃烧科学与技术》2013年第5期457-463,共7页Journal of Combustion Science and Technology

基　　金：国家自然科学基金资助项目(51076045)

摘　　要：应用量子化学从头计算研究了汞与含氟物质的反应机理．计算得到汞／氟体系中有关分子结构的键长和键角值，并与文献值及美国国家标准技术局（NIST）中的理论值比较，以验证计算方法和基组的准确性．优化得到反应物、中间体、过渡态和产物的几何构型，计算活化能和指前因子．采用经典过渡态理论计算了298～1500K温度范围内各基元反应的反应速率常数，比较分析了不同温度下各反应速率的变化趋势．计算结果表明，温度低于600K时，各反应速率随温度升高而增大，相对温度高于600K后则更明显．相比于HF，F2对Hg的影响更显著，在所计算的温度范围内，Hg、HgF与F2的反应速率始终保持较高的水平．对于燃煤烟气中的HgO，将其转化为HgF对加速Hg污染物的脱除效果显得十分重要．The ab initio calculation of quantum chemistry was performed to study the reaction mechanism of mercury with fluorine compounds. The bond length and angle of each molecular structure for Hg/F system were obtained and compared with literature results and NIST experimental data. The geometric configurations of reactants, intermediates, transition states and products were optimized. Then, the activation energies and pre-exponential factors were calculated. The transition state theory was used to calculate the reaction rate within the temperature range of 298--1500 K. Besides, the variation tendency of each reaction with temperature was studied. The results show that reaction rate increases significantly before temperature reaches about 600 K. Compared to HF, F2 obviously promotes Hg oxidation. The rates of reaction Hg ＋ F2→HgF ＋ F and reaction HgF ＋ F2→HgF2 ＋ F stay at a high level within the whole temperature range. For HgO existing in the flue gas, it is very important to convert it into HgF.

关 键 词：煤燃烧 汞 氟化物 量子化学计算 反应机理 

分 类 号：O643.11[理学—物理化学]