无机盐工业
主管:中海油天津化工研究设计院有限公司
主办:中海油天津化工研究设计院有限公司
   中海油炼油化工科学研究院(北京)有限公司
   中国化工学会无机酸碱盐专业委员会
ISSN 1006-4990 CN 12-1069/TQ

无机盐工业 ›› 2025, Vol. 57 ›› Issue (5): 71-78.doi: 10.19964/j.issn.1006-4990.2024-0204

• 研究与开发 • 上一篇    下一篇

分子筛拓扑结构对甲缩醛羰基化影响的反应机理研究

高绍磊1,2(), 王莹利1, 亓良1()   

  1. 1.中国科学院大连化学物理研究所,低碳催化技术国家工程研究中心,辽宁 大连 116023
    2.中国科学院大学,北京 100049
  • 收稿日期:2024-04-09 出版日期:2025-05-10 发布日期:2024-06-18
  • 通讯作者: 亓良(1989— ),男,博士,副研究员,研究方向为分子筛催化;E-mail:qlyanfei920@dicp.ac.cn
  • 作者简介:高绍磊(1998— ),男,硕士研究生,研究方向为分子筛催化甲缩醛羰基化反应;E-mail:gaoshaolei@dicp.ac.cn
  • 基金资助:
    中国科学院青年创新促进会会员人才专项(2023193)

Mechanism study on influence of zeolite topology on dimethoxymethane carbonylation reaction

GAO Shaolei1,2(), WANG Yingli1, QI Liang1()   

  1. 1. National Engineering Research Center of Lower?Carbon Catalysis Technology,Dalian Institute of Chemical Physics,Chi? nese Academy of Sciences,Dalian 116023,China
    2. University of Chinese Academy of Sciences,Beijing 100049,China
  • Received:2024-04-09 Published:2025-05-10 Online:2024-06-18

摘要:

分子筛催化甲缩醛(DMM)羰基化制甲氧基乙酸甲酯(MMAc)反应是当前最具基础研究价值和工业化前景的C1化学反应之一。分子筛拓扑结构对DMM羰基化反应的活性及选择性影响较大,选择了具有十元环、十二元环孔道及超笼拓扑结构的MFI、MOR及FAU分子筛进行DMM羰基化对比。结果表明,随着分子筛可提供的反应空间逐步增大,DMM羰基化的本征活性及选择性不断提高。羰基化选择性的提高是由于反应空间的增大削弱了双分子DMM的歧化过程,而羰基化活性则受反应过程中酰基生成与酰基转化两步基元反应的共同影响。在排除扩散影响的低转化率动力学条件测试中,FAU表现出比MFI高约9倍的本征活性。通过原位红外直接观察到DMM羰基化过程中MFI与FAU两种分子筛甲氧基乙酰基中间体红外特征吸收峰,该中间体特征峰与歧化酰基甲酰基特征峰相对强度可与羰基化选择性相关联。借助对构效关系的理解及原位红外实验结果,提出了可能的分子筛催化DMM羰基化及歧化反应机理并定性推导出羰基化动力学方程。

关键词: 羰基化反应, 甲缩醛, 分子筛, 原位红外, 动力学

Abstract:

Dimethoxymethane(DMM) carbonylation over zeolites to methyl methoxyacetate(MMAc) is currently one of the most promising C1 chemical reactions for both fundamental research and industrialization.Zeolite topology influences DMM carbonylation evidently.In this work,zeolites with different topology including MFI,MOR and FAU were chosen to compare their DMM carbonylation activity and selectivity.As the increase of reaction space,both DMM carbonylation activity and selectivity were increased gradually.The improved DMM carbonylation selectivity could be attributed to the inhibition of DMM disproportionation and DMM carbonylation activity was rate⁃limited by both the generation and conversion of acyl intermediate.The low conversion kinetics conditions test excluding the influence of diffusion revealed that DMM carbonylation activity for FAU was about 9 times higher than that for MFI.Methoxy acetyl intermediate over MFI and FAU in the process of DMM carbonylation was directly observed by insitu IR,and the relative intensity of carbonylation acyl and disproportionation acyl was positive to DMM carbonylation selectivity.Finally,a possible DMM carbonylation and disproportionation mechanism over zeolites was proposed and a DMM carbonylation kinetic formula was deduced based on the insitu IR results and the understanding of the reaction mechanism.

Key words: carbonylation reaction, dimethoxymethane, zeolite, in?situ IR, kinetic

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