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CF_3I在制冷剂、刻蚀剂、发泡剂、灭火剂以及有机氟工业等领域具有广泛的应用.在活性炭负载碱金属盐的催化下,以CHF_3和碘为原料,可直接合成CF_3I.CF_3及CF_4分别是该反应过程中重要的中间产物和副产物,而积碳则导致催化剂失活的重要原因.因此研究它们的产生机理具有重要意义.对此本文采用密度泛涵理论(DFT)方法进行了研究.结果表明:CF_2及CF_3可以对吸附于graphite(001)表面的CFCF_3进行多步氟夺取,最终得到CF_3、CF_4以及C_2自由基.以上氟夺取反应产生的C_2自由基也导致了实验中的积碳现象.上述反应机理与现有的实验数据相符.
CF_3I has a wide range of applications in the fields of refrigerants, etchants, foaming agents, fire extinguishing agents and organic fluorine industries etc. Under the catalysis of activated carbon supported alkali metal salts, CF_3I.CF_3 and CF_4 are important intermediates and by-products, respectively, while the carbon deposition leads to the deactivation of catalysts. Therefore, it is of great importance to study their mechanism of production.In this paper, density functional theory (DFT) The results show that CF 2 and CF 3 can take multi-step fluorine capture of CFCF 3 adsorbed on the graphite (001) surface, finally obtaining CF 3, CF 4 and C 2 free radicals. Of carbon deposition phenomenon.The above reaction mechanism is consistent with the existing experimental data.