Acta Phys. -Chim. Sin. ›› 2013, Vol. 29 ›› Issue (06): 1273-1280.doi: 10.3866/PKU.WHXB201303183

• CATALYSIS AND SURFACE SCIENCE • Previous Articles     Next Articles

Influence of Surface Acidity of Y Zeolites on the Adsorption of Organic Molecules by In situ Fourier Transform Infrared Spectroscopy

ZHANG Xiao-Tong1, YU Wen-Guang1, QIN Yu-Cai2, DONG Shi-Wei1, PEI Ting-Ting1, WANG Lin1, SONG Li-Juan1,2   

  1. 1 Key Laboratory of Petrochemical Catalytic Science and Technology, Liaoning Province, Liaoning ShiHua University, Fushun 113001, Liaoning Province, P. R. China;
    2 College of Chemistry and Chemical Engineering, China University of Petroleum (East China), Qingdao 266426, Shandong Province, P. R. China
  • Received:2013-01-02 Revised:2013-03-18 Published:2013-05-17
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (20976077, 21076100), Major Program of Petroleum Refining of Catalyst of Petro China Company Limited (10-01A-01-01-01), Innovation Team of Liaoning Province Colleges, China (200T110), and Construction Project of Liaoning Province High-end Talent Team.

Abstract:

The surface acidity of Y-type zeolites (HY and NaY) modified by solid state ion exchange (SSIE) and liquid phase ion exchange were characterized by in situ Fourier transform infrared (FTIR) spectroscopy using pyridine as the probe molecule (Py-FTIR). The adsorption of single probe molecules (thiophene, cyclohexene and benzene) and double probe molecules (thiophene and cyclohexene, thiophene and benzene) compared with sorbents were studied using in situ FTIR spectroscopy. The results indicated that the Brönsted acid (B acid) of HY (L-CeY) is the catalytic center of cyclohexene dimerized alkenyl carbenium ions and thiophene oligomerization, while the Lewis acid (L acid) is the major center of adsorption of thiophene, cyclohexene, and benzene. In addition, there is strong chemisorption and competitive adsorption of cyclohexene and thiophene, which provides evidence for the poor performance of removing sulfur. The S-CeY zeolite has abundant of weak Lewis acid sites. The sorbent is good at absorbing thiophene, while the influence of the competition adsorption of cyclohexene was not predominately. As to NaY zeolite, there is no preference for adsorption of thiophene, cyclohexene and benzene.

Key words: In situ Fourier tansform infrared spectroscopy, Modified Y zeolite, Surface acidity, Competitive adsorption, Catalytic reaction

MSC2000: 

  • O643