• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>The journal of physical chemistry, A. Molecules, spectroscopy, kinetics, environment, & general theory >Relative rate study of the kinetics, mechanism, and thermodynamics of the reaction of chlorine atoms with CF _3CF=CH _2 (HFO-1234yf) in 650-950 Torr of N _2 or N _2/O _2diluent at 296-462 K
【24h】

Relative rate study of the kinetics, mechanism, and thermodynamics of the reaction of chlorine atoms with CF _3CF=CH _2 (HFO-1234yf) in 650-950 Torr of N _2 or N _2/O _2diluent at 296-462 K

机译：氯原子与CF _3CF = CH _2（HFO-1234yf）在296-462 K的N _2或N _2 / O _2稀释剂中的CF _3CF = CH _2（HFO-1234yf）反应的动力学，机理和热力学的相对速率研究

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

The rate constant of the reaction Cl + CF _3CF=CH _2 (k _1) has been measured relative to several reference species using the relative rate technique with either gas chromatographic analysis with flame-ionization detection (GC/FID) or Fourier transform infrared (FTIR) analysis. Cl atoms were generated by UV irradiation of Cl _2/CF _3CF=CH _2/reference/N _2/O _2 mixtures. At 300-400 K in the presence of >20 Torr O _2, k _1 = 1.2 × 10 ~(-11) e ~((+1100/RT)) cm ~3 molecule ~(-1) s ~(-1). In N _2 diluent, k _1 has a sharp negative temperature coefficient resulting from the relatively small exothermicity of the following reactions: (1a) Cl + CF _3CF=CH _2 ? CF _3CFClCH _2(?); (1b) Cl + CF _3CF=CH _2 ? CF _3CF(?)CH _2Cl (reaction 1), which were determined in these experiments to be ～16.5 (±2.0) kcal mol ~(-1). This low exothermicity causes reaction 1 to become significantly reversible even at ambient temperature. The rate constant ratio for the reaction of the chloroalkyl radicals formed in reaction 1 with Cl _2 (k _2) or O _2 (k _3) was measured to be k _2/k _3 = 0.4 e ~(-(3000/RT)) for 300-400 K. At 300 K, k _2/k _3 = 0.0026. The reversibility of reaction 1 combined with the small value of k _2/k _3 leads to a sensitive dependence of k _1 on the O _2 concentration. Products measured by GC/FID as a function of temperature are CF _3CFClCH _2Cl, CF _3COF, and CH _2Cl _2. The mechanism leading to these products is discussed. The rate constant for the reaction Cl + CF _3CFClCH _2Cl (k _(11)) was measured as a function of temperature (300-462 K) at 760 Torr to be k _(11) = 8.2 × 10 ~(-12) e ~(-(4065/RT)) cm ~3 molecule ~(-1) s ~(-1). Rate constants relative to CH 4 for the reactions of Cl with the reference compounds CH _3Cl, CH _2Cl _2, and CHCl _3 were measured at 470 K to resolve a literature discrepancy. (R = 1.986 cal K ~(-1) mol ~(-1)).
机译：已使用相对速率技术通过带有火焰电离检测的气相色谱分析（GC / FID）或傅立叶变换红外光谱（GC / FID）相对于几种参考物质测量了反应Cl + CF _3CF = CH _2（k _1）的速率常数（ FTIR）分析。通过Cl_2 / CF_3CF = CH_2 /参比/ N_2 / O_2混合物的UV辐射产生Cl原子。在300-400 K且> 20 Torr O _2的情况下，k _1 = 1.2×10〜（-11）e〜（（+ 1100 / RT））cm〜3分子〜（-1）s〜（-1 ）。在N _2稀释剂中，k _1具有急剧的负温度系数，这是由于以下反应的相对较小的放热引起的：（1a）Cl + CF _3CF = CH _2？ CF _3CFClCH _2（？）; （1b）Cl + CF _3CF = CH _2？ CF _3CF（α）CH _2Cl（反应1），在这些实验中确定为〜16.5（±2.0）kcal mol〜（-1）。这种低放热导致反应1甚至在环境温度下也变得可逆。测定反应1中形成的氯烷基与Cl _2（k _2）或O _2（k _3）反应的速率常数比为k _2 / k _3 = 0.4 e〜（-（3000 / RT））对于300-400K。在300 K时，k _2 / k _3 = 0.0026。反应1的可逆性与k _2 / k _3的小值结合导致k _1对O _2浓度的敏感依赖性。通过GC / FID测量的随温度变化的产物为CF _3CFClCH _2Cl，CF _3COF和CH _2Cl _2。讨论了导致这些产品的机制。在760 Torr下测量反应Cl + CF _3CFClCH _2Cl（k _（11））的速率常数作为温度的函数（300-462 K）为k _（11）= 8.2×10〜（-12） e〜（-（4065 / RT））cm〜3分子〜（-1）s〜（-1）。在470 K下测量Cl与参考化合物CH _3Cl，CH _2Cl _2和CHCl _3的反应相对于CH 4的速率常数，以解决文献差异。 （R = 1.986cal K〜（-1）mol〜（-1））。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号