Effects of the crystallization time on the mesoporous structure, texture, morphology and styrene oxidation performances of V-MCM-41

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• 作者：Junqiang Xu^a ; ^{xujunqiang@cqut.edu.cn} ; Qiang Zhang^a ; Fang Guo^a ; ^{guofang@cqut.edu.cn} ; Jingping Hong^b ; Wei Chu^c
• 关键词：V-MCM-41 molecular sieves ; Crystallization time effects ; Crystallinity ; Catalytic selectivity
• 刊名：Journal of Energy Chemistry
• 出版年：2016
• 出版时间：November 2016
• 年：2016
• 卷：25
• 期：6
• 页码：1058-1063
• 全文大小：999 K
• 卷排序：25

文摘

The new V-MCM-41 molecular sieves with good ordered hexagonal mesoporous structure and crystallinity were synthesized through in-situ hydrothermal preparation method. The effects of the crystallization time were discussed. The synthesized samples were characterized by X-ray diffraction, N2 adsorption/desorption, Fourier transformed infrared and scanning electron microscopy. The different structures, textures, morphologies of V-MCM-41 obtained with different crystallization times were observed and analyzed on the basis of the characterized results. The results showed that the V-MCM-41 molecular sieve obtained at 110 °C for 48 h crystallization times was of good spherical morphology, ordered hexagonal structure, most uniform pore size distribution and high surface area compared with other samples. Meanwhile, the V-MCM-41 molecular sieve with the high skeleton Si condensation and the good crystallinity was obtained. The heteroatom could be incorporated into MCM-41 framework with increasing crystallization times, which was beneficial to improve the catalytic activity and selectivity of pure siliceous MCM-41. The V-MCM-41 showed the good catalytic selectivity in catalytic oxidation of styrene using hydrogen peroxide, and the selectivity of the benzaldehyde and phenylacetic acid reached 30.68% and 49.44%, respectively.