【摘要】 用热天平研究了不同SiO₂/Al₂O₃和孔道结构的HZSM-5型沸石在甲醇-汽油转化中的积炭行为。采用催速老化试验及分子探针方法关联了积炭与催化剂表面酸、孔道结构、催化活性变化的关系,探讨了积炭、老化和失活机理。研究表明,ZSM-5沸石积炭与老化倾向主要决定于它的结构特征及表面酸性,积炭导致沸石强酸位的显著损失及甲醇-烃转化历程的规律变化。更多还原

【Abstract】 The coking behavior of HZSM-5 zeolite with various SiO₂/Al₂O₃ and channel structure in the conversion of methanol to gasoline was investigated by means of thermogravimetric analysis.Accelerated aging test and molecular probe method were applied to relate carbon deposition with the change of surface acidity and channel structure and catalytic properties of HZSM-5 zeolite catalysts. The carbon deposition, aging and deactivation mechanism are discussed.It was shown that the coking and aging tendency of ZSM-5 was related to the change of structure and surface acidity.The carbon deposition led to the loss of the stronger acid sites of zeolite and to the change of the reaction pathway of methanol to hydrocarbons.更多还原