Acta Phys. -Chim. Sin. ›› 1993, Vol. 9 ›› Issue (06): 827-831.doi: 10.3866/PKU.WHXB19930620

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A Study on Acidity and Coking Activity of (NH4)2SiF6 Dealuminated Faujasites

Luan Zhao-Hua; Zhang Ying-Zhen; Zheng Lu-Bin   

  1. Dalian Institute of Chemical Physics, Chinese Acadmey of Sciences, Dalian 116023
  • Received:1992-04-06 Revised:1992-08-25 Published:1993-12-15
  • Contact: Zhang Ying-Zhen

Abstract: Acidity and coking activity of(NH_4)_2SiF_6 dealuminated faujasites have been investigated by means of infrared spectroscopy. Results show that with the increasing framework Si/Al ratio of (NH_4)_2SiF_6 dealuminated Faujasties, (1) Pyridine can interact gradually with the OH groups in the small cavites, while partial OH groups in supercages can not interact with pyridine, (3) the amount of bronsted acid sites dcreases, while the amount of its strong part increases. There is no Lewis acid essentially, (4) the coking rate and coke quantity both decrease, which is in consistent with the acidity of faujasites determined by pyridine.

Key words: Faujasites, Dealumination, Coke formation