In situ Diffuse Reflectance FTIR Spectroscopy Characterization of Titanium Silicalite-1 Catalytic Oxidization of Styrene
ZHANG Ping1,WANG Le-fu2,CHEN Yong-heng1
1. Guangzhou Key Laboratory of Pollution Control and Isotope Application Technology, School of Environmental Science and Engineering, Guangzhou University, Guangzhou 510006, China 2. Department of Chemical Engineering, South China University of Technology, Guangzhou 510640, China
Abstract：The Stability of framework of titanium silicalite-1 (TS-1) was investigated by high temperature diffuse reflectance FTIR spectroscopy (DRIFTS), and the results showed that the 960 cm-1 peak belonging to Ti-framework was stabilized at 673 K, but the two peaks belonging to framework shifted to lower frequencies by about 13 cm-1 at 673 K. The effect on the framework after H2O2 adsorption was discussed. The results showed that the 960 cm-1 peak lowered and shifted to high frequencies by about 11 cm-1,but it recovered with vacuum or heating up. It was suggested that the 960 cm-1 peak characterizes TiO, and this explained why the 960 cm-1 peak shifted to high frequencies well. TS-1 catalytic oxidization of styrene was investigated by in situ DRIFTS. The reaction process was detected and phenyl aldehyde was the main product. Based on in situ analysis, it was proposed that H2O2 was adsorbed on Ti in framework of TS-1 to form active center.
[1] Taramasso M, Perego G, Notari B. Preparation of Porous Crystalline Synthetic Material Comprised of Silicon and Titanium Oxides. US 4 410 501, 1983. [2] Perego Carloa, Carati Angelaa, Ingallina Patriziaa, et al. Applied Catalysis，A General, 2001, 221(30): 63. [3] Tong D On, Kapoor M P, Joshi P N, et al. Catalysis Letters. 1997, 44: 171. [4] ZHANG Ping, LIANG Min-hua, CHEN Yong-heng(张 平, 梁敏华, 陈永亨). Spectroscopy and Spectral Analysis(光谱学与光谱分析)，2007, 27(1): 54. [5] ZHANG Ping, WANG Le-fu, XU Jian-chang (张 平, 王乐夫, 徐建昌). Chinese J. Anal. Chem.(分析化学), 2002, 30(9): 1096. [6] Boccuti M R, Rao K M, Zecchina A, et al. Studies in Surface Science and Catalysis, 1989, 48: 133. [7] Huybrechts D R C, Buskens Ph L, Jacobs P A. Studies in Surface Science and Catalysis, 1992, 72: 21.
