根据实验现象和对积炭物组成进行的GC-MS分析结果,提出了N2O和苯在Fe-ZSM-5分子筛催化剂上进行催化氧化反应的的失活动力学模型,即产物苯酚引起的连串失活。采用固定床积分反应器系统测定了由催化剂失活引起的N2O转化率随运行时间的变化,所得实验数据用于失活动力学模型参数估值。模型表明:较低反应温度和苯相对N2O过量都可减缓催化剂的失活速率。模型统计检验表明:所得失活动力学方程在显著性水平α=0.05下有较高的拟合精度和可信度。该模型对深入了解N2O一步氧化苯制苯酚反应及指导反应器和再生器设计均具有重要的意义。
The experiments of one-step oxidation benzene to phenol with N2O over Fe-ZSM-5 zeolite were carried out on a fixed-bed integral reactor. Based on the experimental phenomena and the GC-MS analysis results of the carbon depositing on the catalyst, it was conjectured that, in above oxidation reaction, it is the product (phenol) which causes the tandem deactivation of the catalyst. A mathematical deactivation kinetics model for above oxidation reaction was proposed, and the experimental data were adopted for estimating the parameters of the model proposed. The deactivation kinetics model indicates that the lower temperature and the excess amount of benzene in the ratio of raw material will lead to the decrease of the deactivation rate of the catalyst. The statistics test shows that the deactivation kinetics equations proposed fit well with the experimental data and are highly credible under the condition of the significance level α = 0.05. The proposed deactivation kinetics model is helpful for understanding the reaction of one-step oxidation benzene to phenol with N2O and is helpful for the design of the one-step reactor and catalyst regenerator too.