摘要
研究了等规聚丙烯水相悬浮热氯化过程的控制步骤,认为随着氯化的进行,氯化过程从表面反应控制逐渐转向灰层扩散控制,并且灰层扩散控制对整个过程起主导作用。对于前期的表面反应控制,根据反应历程提出了聚丙烯水相悬浮热氯化反应机理,并建立了自由基链式反应动力学模型,模型方程为:[]y1=-ln(1-Cl2/0.464)=Kt。对后期的灰层扩散控制,运用非催化气-固反应模型对其作了分析,并得出了转化率方程:[][]23y2=1-3(1-Cl2/0.464)+2(1-Cl2/0.464)=t/τ0。本研究可供等规聚丙烯非均相氯化参考。
The control steps of the thermal chlorination of isotatic polypropylene in aqueous suspension were studied. It shows that the chlorination turns from the surface reaction-control to the ash layer diffusion-control reaction as the chlorination reaction proceeds, and the ash layer diffusion-control dominates the chlorination process. The reaction mechanism of the early surface reaction-control stage of the chlorination of polypropylene was proposed and a kinetic model of the radical chain reaction was established. The integral equation of the kinetic model is: y1=-ln(1-[Cl2]/0.464)=Kt. For the later ash layer diffusion-control reaction stage, it was analyzed by using the noncatalytic gas-solid reaction model and the conversion equation was suggested: y2=1-3(1-[Cl2]/0.464)2/3 + 2(1-[Cl2]/0.464)=t/τ0, in which τ0 is the end time of complete conversion. Moreover, the relationships of τ0 with R2 (original particle size), DeCAS (the Cl2 mass transfer rate) with T(temperature), etc. were discussed and summarized. The conclusions are helpful to the heterogeneous chlorination of IPP.
出处
《高校化学工程学报》
EI
CAS
CSCD
北大核心
2005年第4期480-485,共6页
Journal of Chemical Engineering of Chinese Universities
关键词
等规聚丙烯
水相悬浮
热氯化
反应动力学
Chlorination
Diffusion
Integral equations
Mathematical models
Particle size analysis
Reaction kinetics
