Acta Chimica Sinica ›› 2022, Vol. 80 ›› Issue (4): 438-443.DOI: 10.6023/A21120619 Previous Articles     Next Articles

Special Issue: 中国科学院青年创新促进会合辑



江辉波a,b, 林姗姗a,b, 徐玉平b, 孙径b, 徐忠宁b,*(), 郭国聪b,*()   

  1. a 福州大学 石油化工学院 福州 350116
    b 中国科学院福建物质结构研究所 结构化学国家重点实验室 福州 350002
  • 投稿日期:2021-12-31 发布日期:2022-04-28
  • 通讯作者: 徐忠宁, 郭国聪
  • 作者简介:
  • 基金资助:
    国家重点研发计划项目(2021YFB3801604); 国家重点研发计划项目(2017YFA0206802); 国家重点研发计划项目(2017YFA0700103); 国家重点研发计划项目(2018YFA0704500); 国家自然科学基金委员会面上项目(22172171)

Lewis Acid in NaY Zeolite High Selectively Catalyze Methanol to Dimethoxymethane via Methyl Nitrite

Huibo Jianga,b, Shanshan Lina,b, Yuping Xub, Jing Sunb, Zhongning Xub(), Guocong Guob()   

  1. a College of Chemical Engineering, Fuzhou University, Fuzhou 350116, China
    b State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002, China
  • Received:2021-12-31 Published:2022-04-28
  • Contact: Zhongning Xu, Guocong Guo
  • About author:
    Dedicated to the 10th anniversary of the Youth Innovation Promotion Association, CAS.
  • Supported by:
    National Key Research and Development Program of China(2021YFB3801604); National Key Research and Development Program of China(2017YFA0206802); National Key Research and Development Program of China(2017YFA0700103); National Key Research and Development Program of China(2018YFA0704500); General Program of National Natural Science Foundation of China(22172171)

Dimethoxymethane (DMM) has wide application in resin, solvent, and fuel fields as a fundamental organic chemical. The traditional route to synthesize DMM using methanol and formaldehyde as reactants via condensation reaction has poor efficiency. Methyl nitrite (MN), which is obtained by the reaction of methanol, oxygen and nitrite monoxide without catalysts, could be used as raw material to produce DMM through catalytic decomposition. The current work systematically investigated the catalytic activity and selectivity to DMM of several molecular sieves in MN decomposition reaction. The results show that the activity trend is NaY (97%)=HY (97%)>HZSM-5 (90%)>Hβ (89%)>NaZSM-5 (18%)>Naβ (6%), and the DMM selectivity trend is NaY (53%)>HY (12%)=Naβ (12%)>NaZSM-5 (7%)>Hβ (4%)>HZSM-5 (3%). X-ray diffraction (XRD), Brunner-Emmet-Teller measurements (BET), scanning electron microscope (SEM) and Pyridine-IR (Py-IR) experiments have been employed to reveal the structure-activity relationship of these molecular sieves. Combining the temperature-programmed desorption of CO2 experiments (CO2-TPD) data with the evaluation results of the catalytic performance of the zeolite catalyst, the basic sites of the zeolite have no direct connection to the catalytic MN decomposition process. Meanwhile, the calcination temperature experiment of NH4-zeolite and the catalytic performance test experiment of NaY-tetraethoxysilane (TEOS) further proved that the acid site played an essential role in promoting the decomposition of MN, and the results show that the Lewis acidity sites of Na+ and low-coordinated Al metal center are key factors to catalyze MN to DMM high selectively. We have proposed the MN decomposition mechanism. In the process of MN decomposition, there are both proton generation and proton consumption processes. Intermediates in the decomposition process are easily protonated by Brönsted acid sites to form by-products. The Lewis acid site of zeolite is generally a low-coordinated Al metal center, which can effectively adsorb and stabilize the oxygen-containing intermediates generated during the decomposition of MN, especially the methoxy and formaldehyde intermediates involved in the production of DMM, which is very beneficial to

the decomposition of MN to DMM. We believe that the research in this paper can provide a new and efficient synthetic route for DMM.

Key words: methyl nitrite, dimethoxymethane, zeolite, NaY, Lewis acid