摘要
氟胺类物质是最有希望作为哈龙替代品的含氮化合物之一,全氟三乙胺作为典型的氟胺类物质具有良好的灭火效果。为研究全氟三乙胺热解机理,在管式加热炉内对全氟三乙胺进行热分解,通过GC-MS分析全氟三乙胺在不同温度条件下的热解产物,并用Gaussian软件对其热解反应路径进行理论计算。结果表明:保持停留时间为10 s,全氟三乙胺的初始热解温度为600℃,750℃完全热解,热解产物有C_(4)F_(9)N、C_(3)F_(7)N、C_(2)F_(6)和C_(3)F_(8),热解温度较低时C_(4)F_(9)N体积分数最大,热解温度较高时C_(3)F_(7)N体积分数最大。在全氟三乙胺热解反应路径计算中,全氟三乙胺分子中的C—C键断裂后存在1条反应路径,可生成实验产物中的C_(3)F_(8);全氟三乙胺分子的C—N键断裂后存在3条反应路径,可生成实验产物中的C_(3)F_(7)N、C_(4)F_(9)N和C_(2)F_(6)。全氟三乙胺热解后产生的CF_(3)自由基可与H、OH自由基发生反应,从而产生灭火作用。此外,其热解产物C_(4)F_(9)N和C_(3)F_(7)N具有C N双键,更容易与燃烧活泼自由基·OH、·H发生化学作用,对研究全氟三乙胺的灭火机理具有十分重要的意义。
Fluorine amines are one of the most promising nitrogen-containing compounds as halon substitutes.As a typical fluorine amine,perfluorotriethylamine has good fire-extinguishing effect.In order to reveal the pyrolysis mechanism of(C_(2)F_(5))_(3)N,its pyrolysis products under different temperature conditions are obtained by using GC-MS,and then the pyrolysis reaction paths are theoretically calculated by using Gaussian.The results show that the initial pyrolysis temperature of(C_(2)F_(5))_(3)N is about 600℃,and the complete pyrolysis is around 750℃,by keeping the residence time at 10 s.The pyrolysis products are C_(4)F_(9)N,C_(3)F_(7)N,C_(2)F_(6) and C_(3)F_(8).The volume fraction of C_(4)F_(9)N is the largest at a low pyrolysis temperature,while the volume fraction of C_(3)F_(7)N is the largest at a high pyrolysis temperature.In the calculation of the pyrolysis reaction path of(C_(2)F_(5))_(3)N,there is one reaction pathway would generate C_(3)F_(8) after the breaking of C-C bond in the(C_(2)F_(5))_(3)N molecule.In another pyrolysis reaction path of(C_(2)F_(5))_(3)N,C_(2)F_(6) and the stable product C_(4)F_(9)N would be generated after the breaking of C-N bond.The breaking of C-N bond in(C_(2)F_(5))_(3)N would produce an unstable product N(C_(2)F_(5))_(2)N,the followed breaking of the C-C bond will generate C_(3)F_(7)N.The main pyrolysis products of(C_(2)F_(5))_(3)N are C_(4)F_(9)N and C_(3)F_(7)N,the two products have C N double bonds and can more easily interact with the combustion active.
作者
梁天水
王新科
刘德智
钟委
LIANG Tianshui;WANG Xinke;LIU Dezhi;ZHONG Wei(School of Mechanics and Safety Engineering,Zhengzhou University,Zhengzhou 450001,Henan,China)
出处
《化工学报》
EI
CSCD
北大核心
2022年第10期4762-4768,共7页
CIESC Journal
基金
国家自然科学基金项目(51874258)。
关键词
全氟三乙胺
热解
高斯计算
反应路径
机理
(C2F5)3N
pyrolysis
Gaussian calculation
reaction path
mechanism
