Acta Phys. -Chim. Sin. ›› 2012, Vol. 28 ›› Issue (06): 1467-1473.doi: 10.3866/PKU.WHXB201203312

• CATALYSIS AND SURFACE SCIENCE • Previous Articles     Next Articles

Effect of Surface Acidity of CuO-SBA-15 on Adsorptive Desulfurization of Fuel Oils

SHAO Xin-Chao1, DUAN Lin-Hai1, WU Yu-Ye1, QIN Yu-Cai2, YU Wen-Guang1, WANG Yuan1, LI Huai-Lei1, SUN Zhao-Lin1, SONG Li-Juan1,2   

  1. 1. Key Laboratory of Petrochemical Catalytic Science and Technology, Liaoning ShiHua University, Fushun 113001, Liaoning Province, P. R. China;
    2. College of Chemistry and Chemical Engineering, China University of Petroleum (East China), Qingdao 257061, Shandong Province, P. R. China
  • Received:2012-02-27 Revised:2012-03-29 Published:2012-05-17
  • Contact: SONG Li-Juan E-mail:lsong56@263.net
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (20976077, 21076100), National Key Basic Research Program of China (973) (2007CB216403), and Innovation Team of Liaoning Province Colleges, China.

Abstract: Solid-state grinding is a simple and effective technique to incorporate active species into the channels of mesoporous materials with different degrees of filling. Using this method, different concentrations of CuO were loaded into the mesochannels of as-prepared mesoporous silica (APS) and calcined SBA-15 (CS). The samples were prepared and characterized using X-ray diffraction (XRD), N2 physisorption, and Fourier transform infrared (FTIR) spectroscopy. The relative number of hydroxyl groups was studied by in situ FTIR spectroscopy, and the total surface acidity of the adsorbents was monitored by FTIR spectroscopy at 423 K using pyridine as a probe. Desulfurization of fluid catalytic cracking (FCC) fuel oils using these materials was investigated. The results suggest that CuO interacts directly with support hydroxyl groups to form [Si-O-Cu-O-Si] linkages in the mixtures, which can effectively constrain the condensation of hydroxyl groups in SBA-15 to improve the mesostructure of the adsorbents during calcination. Saturated coverage of the surface of APS is reached using 3 mmol·g-1 CuO. However, using CS, aggregation of CuO is observed in the material containing 3 mmol·g-1 of CuO. Both the surface acidity and desulfurization performance significantly increase upon modification of SBA-15 with CuO, and then decrease slowly as the concentration of CuO is increased. The sample containing 3 mmol·g-1 CuO shows the highest Lewis acidity and desulfurization performance. The Lewis acidity of the adsorbents matches the adsorptive desulfurization performance. It is also demonstrated that reduction of charge density around copper atoms helps to form Lewis acid sites.

Key words: SBA-15 mesoporous material, Surface acidity, Hydroxyl group, Adsorptive desulfurization, Lewis acid

MSC2000: 

  • O643