甲烷与丙烷混合无氧芳构化反应机理及反应动力学研究  

Study on Mechanism and Kinetics of Non-oxidative Aromatization Using Methane and Propane

作　　者：许磊 樊金龙 徐国昊 XU Lei;FAN Jinlong;XU Guohao(PetroChina Research Institute of Urumqi Petrochemical Company,Urumqi 830019,China;State Key Laboratory of Chemical Engineering,East China University of Science and Technology,Shanghai 200237 China)

机构地区：[1]中国石油乌鲁木齐石化公司研究院,新疆乌鲁木齐830019 [2]华东理工大学化学工程联合国家重点实验室,上海200237

出　　处：《化学反应工程与工艺》2023年第3期246-251,共6页Chemical Reaction Engineering and Technology

基　　金：中国石油天然气股份有限公司科研项目(2019A-2409-01)。

摘　　要：为促进甲烷的无氧芳构化反应,考察了在ZSM-5和Zn/ZSM-5分子筛催化剂上丙烷对甲烷无氧芳构化反应的影响,并通过原位红外光谱实验探究了甲烷和丙烷混合芳构化的反应历程。结果表明:在甲烷芳构化中引入丙烷可促进反应物的转化和芳烃产物的形成,Zn元素可促进甲烷的活化。原位红外光谱实验发现,甲烷在Zn活性位点上会形成Zn-CH_(3)物种,然后与丙烷芳构化形成的苯结合,进一步促进苯环支链低聚物的形成,从而促进芳烃的形成。在550~650℃反应温度下,对Zn/ZSM-5催化剂上甲烷丙烷混合无氧芳构化反应动力学进行了研究,发现相同反应温度下芳烃各产物生成速率常数的大小为:k(苯)>k(甲苯)>k(二甲苯),其生成苯、甲苯和二甲苯反应的表观活化能分别为25.1,31.9和77.9 kJ/mol,苯为主要芳烃产物。To promote the oxygen-free aromatization of methane,effect of propane on the oxygen-free aromatization of methane over ZSM-5 and Zn/ZSM-5 catalysts was investigated,and the reaction process of the mixed aromatization of methane and propane was investigated by in-situ infrared spectroscopy.The results showed that the introduction of propane into methane aromatization could promote the conversion of reactants and the formation of aromatic products,and Zn species could promote the activation of methane.Through in-situ infrared spectroscopy,it was found that a large number of Zn-CH_(3) species were formed at the active site of Zn and then combined with benzene formed by aromatization of propane,which further promoted the formation of branched chain oligomers of phenyl rings,thus promoting the formation of aromatic hydrocarbons.The chemical kinetics of aromatization of methane and propane over Zn/ZSM-5 catalyst was investigated at 550-650℃.It was found that the formation rate constant of benzene was the largest,followed by toluene and xylene at the same reaction temperature.The apparent activation energies for the generation of benzene,toluene and xylene were 25.1,31.9 and 77.9 kJ/mol respectively.Benzene was the main aromatic product.

关 键 词：甲烷 丙烷 无氧芳构化 反应机理 反应动力学 

分 类 号：TQ241[化学工程—有机化工]