SCI和EI收录∣中国化工学会会刊

中国化学工程学报 ›› 2020, Vol. 28 ›› Issue (10): 2577-2586.DOI: 10.1016/j.cjche.2020.05.013

• Catalysis, Kinetics and Reaction Engineering • 上一篇    下一篇

Direct synthesis of hydrogen peroxide over Pd nanoparticles embedded between HZSM-5 nanosheets layers

Guozhu Liu1, Hairui Liang1, Yajie Tian2, Bofeng Zhang1, Li Wang1   

  1. 1 Key Laboratory for Green Chemical Technology of Ministry of Education, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China;
    2 College of Chemistry and Chemical Engineering, Henan University, Kaifeng 475001, China
  • 收稿日期:2020-01-23 修回日期:2020-05-07 出版日期:2020-10-28 发布日期:2020-12-03
  • 通讯作者: Guozhu Liu, Hairui Liang, Yajie Tian, Bofeng Zhang, Li Wang
  • 基金资助:
    Financial supports by the National Natural Science Foundation of China (21776210) Science and Technology Research Project of Henan Province (No. 202102210048) are gratefully acknowledged.

Direct synthesis of hydrogen peroxide over Pd nanoparticles embedded between HZSM-5 nanosheets layers

Guozhu Liu1, Hairui Liang1, Yajie Tian2, Bofeng Zhang1, Li Wang1   

  1. 1 Key Laboratory for Green Chemical Technology of Ministry of Education, School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China;
    2 College of Chemistry and Chemical Engineering, Henan University, Kaifeng 475001, China
  • Received:2020-01-23 Revised:2020-05-07 Online:2020-10-28 Published:2020-12-03
  • Contact: Guozhu Liu, Hairui Liang, Yajie Tian, Bofeng Zhang, Li Wang
  • Supported by:
    Financial supports by the National Natural Science Foundation of China (21776210) Science and Technology Research Project of Henan Province (No. 202102210048) are gratefully acknowledged.

摘要: Direct synthesis of hydrogen peroxide (DSHP) was studied over Pd loaded on HZSM-5 nanosheets (Pd/ZN). Pd nanoparticles with average size of ca. 4.3 nm were introduced into the adjacent nanosheet layers (thickness of ca. 2.9 nm) by impregnation method. Pd/ZN with theoretical Si/Al molar ratio of 25 showed the highest selectivity for H2O2 among the prepared catalysts, together with highest formation rate of H2O2 (38.0 mmol·(g cat)-1·h-1), 1.9 times than that of Pd supported on conventional HZSM-5 zeolite (Pd/CZ-50). Better catalytic performance of nanosheet catalysts was attributed to the promoted Pd dispersion which promoted H2 dissociation, more Brønsted acid sites and stronger metal-support interaction which inhibited the dissociation of O-O bond in H2O2. The embedded structure sufficiently protected the Pd nanoparticles by space confinement which restrained the Pd leaching, leading to a better catalytic stability with 90% activity retained after 3 cycles, which was almost 3 times than that of Pd/CZ-50 (30.4% activity retained).

关键词: HZSM-5 nanosheets, Palladium catalyst, Silica/alumina molar ratio, Metal-support interaction, Direct synthesis of hydrogen peroxide

Abstract: Direct synthesis of hydrogen peroxide (DSHP) was studied over Pd loaded on HZSM-5 nanosheets (Pd/ZN). Pd nanoparticles with average size of ca. 4.3 nm were introduced into the adjacent nanosheet layers (thickness of ca. 2.9 nm) by impregnation method. Pd/ZN with theoretical Si/Al molar ratio of 25 showed the highest selectivity for H2O2 among the prepared catalysts, together with highest formation rate of H2O2 (38.0 mmol·(g cat)-1·h-1), 1.9 times than that of Pd supported on conventional HZSM-5 zeolite (Pd/CZ-50). Better catalytic performance of nanosheet catalysts was attributed to the promoted Pd dispersion which promoted H2 dissociation, more Brønsted acid sites and stronger metal-support interaction which inhibited the dissociation of O-O bond in H2O2. The embedded structure sufficiently protected the Pd nanoparticles by space confinement which restrained the Pd leaching, leading to a better catalytic stability with 90% activity retained after 3 cycles, which was almost 3 times than that of Pd/CZ-50 (30.4% activity retained).

Key words: HZSM-5 nanosheets, Palladium catalyst, Silica/alumina molar ratio, Metal-support interaction, Direct synthesis of hydrogen peroxide