骨架锌Zn-HZSM-5分子筛催化剂上甲醇制汽油反应动力学（英文）

Reaction kinetics of methanol to gasoline over Zn-HZSM-5 catalysts with skeleton Zn

通过水热晶化法,合成含有骨架杂原子Zn的Zn-HZSM-5分子筛催化剂,采用XRD、BET、NH3-TPD表征催化剂结构和物化性能,在微型固定床反应器中测定催化剂的甲醇制汽油反应性能和反应动力学数据,研究Zn-HZSM-5分子筛催化剂的甲醇制汽油本征反应动力学。结果表明,杂原子Zn引入ZSM-5分子筛骨架后增加对产物汽油选择性有利的弱酸量。采用Chen and Reagan建立的甲醇制汽油三集总动力学模型,通过四阶龙格库塔法和最小二乘法对实验数据的回归,计算反应速率常数为k_1=1. 154×10^(12)exp (-97600/RT),k_2=0. 687×10^(12)exp (-105200/RT)和k_3=1. 739×10~7exp (-84700/RT)。以目标残差函数OF参数值为检验模型的标准,模拟值和实验值的相关系数R^2均在0. 993以上。因此Chen and Reagan建立的甲醇制汽油三集总动力学模型可以准确描述Zn-HZSM-5分子筛催化剂的甲醇制汽油反应动力学行为。

Zn-HZSM-5 zeolite catalysts containing skeleton heteroatom Zn were synthesized by in-situ hydrothermal crystallization method. Structure and physic-chemical properties of the catalyst were characterized by XRD,BET and NH3-TPD. The catalytic activity and intrinsic reaction kinetics for methanol to gasoline of Zn-HZSM-5 zeolite were measured in micro fixed bed reactor. Results showed that amount of weak acid beneficial for gasoline selectivity increased when heteroatom Zn was modified into ZSM-5 zeolite skeleton. Using the three-lumped kinetic model of methanol to gasoline established byChen and Reagan,the reaction rate constants were k1= 1. 154 × 1012 exp(-97600/RT),k2= 0. 687 × 1012 exp(-105200/RT) and k3= 1. 739 × 107 exp(-84700/RT) respectively based on experimental data regression by Runge-Kutta method and the least-squares method. Taking the target residual function( OF) parameter value as criterion of test,the correlation coefficients R2 of simulated value and experimental value were higher than 0. 993. Therefore,the methanol to gasoline three-lumped kinetic model established by Chen and Reagan could accurately describe the kinetics of methanol to gasoline reaction on Zn-HZSM-5 zeolite catalysts.