Secondary Crystallization of Na2CO3-Modified HZSM-5 Zeolites with Tetrapropylammonium Hydroxide and Their Catalytic Performance in Thiophene Alkylation Reaction

作者：Liu Dongmei; Kong Feifei; Zhai Yuchun^*; Wang Haiyan

来源：China Petroleum Processing & Petrochemical Technology, 2015, 17(3): 53-60.

• tetrapropylammonium hydroxide
• sodium carbonate
• HZSM-5
• secondary crystallization

The Na2CO3-modified HZSM-5 zeolites were further treated by tetrapropylammonium hydroxide (TPAOH) solution. The effect of TPAOH concentration on the secondary crystallization process was investigated. The resulting samples were characterized by a complementary combination of X-ray diffraction, N-2 adsorption/desorption, scanning electron microscopy, X-ray fluorescence spectroscopy, XPS, Al-27 and Si-29 magic-angle spinning nuclear magnetic resonance spectroscopy, BET and temperature-programmed desorption techniques. The results showed that the secondary crystallization of the HZSM-5 zeolite could result in migration of non-framework species from the internal channels to the zeolite surface and their transformation into framework species. The catalytic activity of these modified samples for thiophene alkylation was evaluated. Both the activity and stability of the catalysts were improved after secondary crystallization.

• 出版日期2015-9
• 单位辽宁石油化工大学; 东北大学