Toluene pretreatment caused many activated toluene species existing on the surface of zeolite HZSM-5, by which the activity of sample was increased. Moreover, variation in the surface Si+/Al+ ratio of HZSM-5 was sensi...Toluene pretreatment caused many activated toluene species existing on the surface of zeolite HZSM-5, by which the activity of sample was increased. Moreover, variation in the surface Si+/Al+ ratio of HZSM-5 was sensitively detected by FABMS.展开更多
Ⅰ. NTRODUCTIONIn order to explain the catalytic properties of zeolite HZSM-5, it is necessary to know the nature, number and strength distribution of acid sites of zeolite, and the temperature programmed desorption (...Ⅰ. NTRODUCTIONIn order to explain the catalytic properties of zeolite HZSM-5, it is necessary to know the nature, number and strength distribution of acid sites of zeolite, and the temperature programmed desorption (TPD) of ammonia or pyridine is one of the most commonly-used methods. Compared with ammonia (pK_b=4.75) and pyri-展开更多
文摘Toluene pretreatment caused many activated toluene species existing on the surface of zeolite HZSM-5, by which the activity of sample was increased. Moreover, variation in the surface Si+/Al+ ratio of HZSM-5 was sensitively detected by FABMS.
文摘Ⅰ. NTRODUCTIONIn order to explain the catalytic properties of zeolite HZSM-5, it is necessary to know the nature, number and strength distribution of acid sites of zeolite, and the temperature programmed desorption (TPD) of ammonia or pyridine is one of the most commonly-used methods. Compared with ammonia (pK_b=4.75) and pyri-