SCI和EI收录∣中国化工学会会刊

中国化学工程学报 ›› 2019, Vol. 27 ›› Issue (8): 1981-1987.DOI: 10.1016/j.cjche.2019.03.027

• Materials and Product Engineering • 上一篇    下一篇

Modification of pillared MFI zeolite nanosheets by nitridation with tailored activity in benzylation of mesitylene and benzyl alcohol

Zhipeng Chen1, Jiajin Huang1, Qiaowen Mu1, Huiyong Chen2, Feng Xu3, Yanxiong Fang1, Baoyu Liu1   

  1. 1 School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou 510006, China;
    2 School of Chemical Engineering, Northwest University, Xi'an 710069, China;
    3 School of Environment and Chemical Engineering, Foshan University, Foshan 528000, China
  • 收稿日期:2018-07-05 修回日期:2019-02-16 出版日期:2019-08-28 发布日期:2019-11-16
  • 通讯作者: Baoyu Liu
  • 基金资助:
    Supported by the Science and Technology Program of Guangzhou, China (201804010172), National Natural Science Foundation of China (21808040, 21706031, 21276052, 21776049), Science and Technology Planning Project of Guangdong Province, China (2012A090300006).

Modification of pillared MFI zeolite nanosheets by nitridation with tailored activity in benzylation of mesitylene and benzyl alcohol

Zhipeng Chen1, Jiajin Huang1, Qiaowen Mu1, Huiyong Chen2, Feng Xu3, Yanxiong Fang1, Baoyu Liu1   

  1. 1 School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou 510006, China;
    2 School of Chemical Engineering, Northwest University, Xi'an 710069, China;
    3 School of Environment and Chemical Engineering, Foshan University, Foshan 528000, China
  • Received:2018-07-05 Revised:2019-02-16 Online:2019-08-28 Published:2019-11-16
  • Contact: Baoyu Liu
  • Supported by:
    Supported by the Science and Technology Program of Guangzhou, China (201804010172), National Natural Science Foundation of China (21808040, 21706031, 21276052, 21776049), Science and Technology Planning Project of Guangdong Province, China (2012A090300006).

摘要: The modification of pillared MFI zeolites was performed by nitridation of silica pillared MFI zeolite nanosheets under NH3 atmosphere with different time. The resultant zeolites were characterized by a complementary combination of X-ray power diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), pyridine-IR spectroscopy and N2 adsorption-desorption isotherms. The analyses showed that the nitridation didn't destroy the crystallinity and specific surface area of zeolites, and the acidity of zeolites can be tailored by tuning the time of nitridation, resulting in the different concentration ratios of Brønsted-to-Lewis (B/L) acid sites. Moreover, the nitrided zeolites exhibited high selectivity to 2-benzyl-1,3,5-trimethylbenzene than parent silica pillared MFI zeolite nanosheets in benzylation of mesitylene with benzyl alcohol. A balance between Brønsted acid sites and Lewis acid sites can inhibit the self-etherification of benzyl alcohol and enhance the selectivity of alkylated product. These experimental data implied that nitridation was an effective method to modulate the acidity of zeolites and the synergy between Brønsted acid sites and Lewis acid sites was a decisive factor to determine the selectivity.

关键词: MFI zeolite, Pillar, Nitridation, Benzylation

Abstract: The modification of pillared MFI zeolites was performed by nitridation of silica pillared MFI zeolite nanosheets under NH3 atmosphere with different time. The resultant zeolites were characterized by a complementary combination of X-ray power diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), pyridine-IR spectroscopy and N2 adsorption-desorption isotherms. The analyses showed that the nitridation didn't destroy the crystallinity and specific surface area of zeolites, and the acidity of zeolites can be tailored by tuning the time of nitridation, resulting in the different concentration ratios of Brønsted-to-Lewis (B/L) acid sites. Moreover, the nitrided zeolites exhibited high selectivity to 2-benzyl-1,3,5-trimethylbenzene than parent silica pillared MFI zeolite nanosheets in benzylation of mesitylene with benzyl alcohol. A balance between Brønsted acid sites and Lewis acid sites can inhibit the self-etherification of benzyl alcohol and enhance the selectivity of alkylated product. These experimental data implied that nitridation was an effective method to modulate the acidity of zeolites and the synergy between Brønsted acid sites and Lewis acid sites was a decisive factor to determine the selectivity.

Key words: MFI zeolite, Pillar, Nitridation, Benzylation