高等学校化学学报 ›› 2023, Vol. 44 ›› Issue (8): 20230059.doi: 10.7503/cjcu20230059

• 物理化学 • 上一篇    下一篇

酸性质调控对Pd/MIL-100(Cr)催化苯甲醇一步氧化制缩醛性能的影响

李子鹏1,2, 耿佳鑫2, 刘颖雅1,2(), 孙志超1,2, 王瑶2, 王安杰1,2()   

  1. 1.大连理工大学精细化工国家重点实验室
    2.化工学院, 大连 116024
  • 收稿日期:2023-02-14 出版日期:2023-08-10 发布日期:2023-04-14
  • 通讯作者: 刘颖雅,王安杰 E-mail:yingya.liu@dlut.edu.cn;ajwang@dlut.edu.cn
  • 基金资助:
    国家自然科学基金(22271038);国家重点研发计划项目(2016YFE0109800)

Effect of Acid Property Regulation on the Performance of Pd/MIL-100(Cr) Catalyzed One-step Oxidation of Benzyl Alcohol to Acetal

LI Zipeng1,2, GENG Jiaxin2, LIU Yingya1,2(), SUN Zhichao1,2, WANG Yao2, WANG Anjie1,2()   

  1. 1.State Key Laboratory of Fine Chemicals
    2.School of Chemical Engineering,Dalian University of Technology,Dalian 116024,China
  • Received:2023-02-14 Online:2023-08-10 Published:2023-04-14
  • Contact: LIU Yingya, WANG Anjie E-mail:yingya.liu@dlut.edu.cn;ajwang@dlut.edu.cn
  • Supported by:
    the National Natural Science Foundation of China(22271038);the National Key Research and Development Program of China(2016YFE0109800)

摘要:

采用水热法合成了金属有机骨架材料MIL-100(Cr), 通过双溶剂浸渍和氢气还原制备了双功能催化剂Pd/MIL-100(Cr). 以苯甲醇一步氧化制缩醛为模型反应, 研究了载体表面酸性质对催化性能的影响. 结果表明, 串联反应可以有效提高苯甲醇氧化反应的速率, 不同还原温度及活化温度均对MIL-100(Cr)的酸性质有影响, 进而影响缩醛产物的选择性. 吡啶吸附红外光谱(Py-FTIR)及氨程序升温脱附(NH3-TPD)表征结果表明, 升高催化剂处理温度, L酸中心增加, B酸中心减少, B酸中心对提高缩醛选择性有利. 在最优条件下, 70 ℃反应12 h, 苯甲醇的转化率大于99.9%, 缩醛的选择性为76.2%. 采用X射线光电子能谱(XPS)表征了Pd物种及载体 MIL-100(Cr)的电子性质, 考察了催化剂的循环稳定性; 通过X射线粉末衍射仪(XRD)、 场发射扫描电子显微镜(SEM)、 氮气吸附-脱附等温线及NH3-TPD表征分析了催化剂失活的原因.

关键词: MIL-100(Cr), 钯, 苯甲醇, 缩醛, 串联反应

Abstract:

MIL-100(Cr) was hydrothermally synthesized and used as a solid-acid catalyst support. Pd nanoparticles were impregnated on MIL-100(Cr) by a double-solvent approach followed by hydrogen reduction to obtain Pd/MIL-100(Cr). One-step tandem conversion of benzyl alcohol to acetal was selected as a model reaction, and the influence of acid property of MIL-100 on the product distribution was investigated. The results showed that Pd/MIL-100(Cr) catalyzed tandem reaction could accelerate the benzyl alcohol oxidation, and different reduction and activation temperatures had an impact on the acid properties of MIL-100(Cr), which in turn affected the selectivity of acetal. The acid properties were characterized by pyridine adsorption infrared spectroscopy(Py-FTIR) and temperature programmed desorption of ammonia(NH3-TPD), the result showed that increasing the catalyst treatment temperature, the L acid sites increased, the B acid sites decreased, and the B acid sites was beneficial to improve the selectivity of acetal. Under optimal conditions, a benzyl alcohol conversion of 99.9% and acetal selectivity of 76.2% can be achieved at 70 ℃ in 12 h. X-ray photoelectron spectroscopy(XPS) analysis was used to characterize the electronic properties of the Pd species and the MIL-100(Cr), the cycling stability of the catalyst was investigated, and the reasons for the deactivation of the catalyst were analyzed by powder X-ray diffraction(XRD), scanning electron microscopy(SEM), N2 adsorption-desorption isotherms and NH3-TPD.

Key words: MIL-100(Cr), Pd, Benzyl alcohol, Acetal, Tandem reaction

中图分类号: 

TrendMD: