多孔催化剂颗粒的内扩散效应对伴有失活的二级反应动力学的影响

Effect of Intraparticle Diffusion on Catalyst Deactivation Kinetics for Second Order Reactions

采用正交配置等数学方法,研究在均匀独立失活的催化反应系统中,内扩散效应对等温球形催化剂失活速率的影响,建立适用于任何内扩散区域的二级反应、m级失活系统的失活有效因子和失活西勒模数的定量关系,对n级反应、m级失活系统也作了相应地推广.运用加压微反-色谱-数据处理机联合装置,通过分析在原颗粒丝光沸石催化剂上进行的临氢甲苯歧化反应的失活数据,研究了内扩散对二级反应失活动力学的影响规律.同时,在实验范围内,建立了一套内扩散存在下的甲苯歧化失活动力学模型.

The effect of intraparticle diffusion on the deactivation rates of isothermal, spherical catalyst pellets for uniform independent deactivation was studied by means of the method of orthogonal collocation. A quantitative relationship between the deactivation effectiveness factor and Thiele modulus was developed for the second order reaction and the mth order deactivation. The extension to the nth order reaction and the mth order deactivation was also discussed. A combined unit of micro-reactor and gas chromatography was used to study the deactivation of catalyst for the disproportionation of toluene over mordenite catalyst. Various diffusion-deactivation kinetic equations were tested and their goodness of fit was discussed. In particular, it was found that the second order reaction and the mth order deactivation rate form agreed with the data.