ie8b00596_si_001.pdf (8.02 MB)
Density Functional Theory Investigation on the Synthesis Mechanism of Vinyl Acetate from Acetylene and Acetic Acid Catalyzed by Ordered Mesoporous Carbon-Supported Zinc Acetate
journal contribution
posted on 2018-05-14, 00:00 authored by Xiuqin Dong, Yuchun Wang, Yingzhe Yu, Minhua ZhangThe
formation mechanism of vinyl acetate in the reaction of acetylene
and acetic acid, which was catalyzed by ordered mesoporous carbon
(OMC) supported zinc acetate, was investigated using density functional
theory (DFT). Since the surface functional groups of carbon support
influence the reaction significantly and play an important role in
catalysis designing, we calculate the elementary steps on pristine
ordered mesoporous carbon and carbon modified with carboxyl, carbonyl,
and hydroxyl, respectively. After calculation, we find that carbonyl
shifts to the epoxy group, which indicates the instability of carbonyl
on the catalyst support. We propose the possible reaction mechanism
and find that the reaction mechanism is not exactly the same with
different functional groups. A remarkably acetate shift will occur
in the existence of carboxyl and the activation barrier of rate-limiting
steps in this case is also reduced, while the hydroxyl and epoxy groups
will increase the barrier to some extent. Therefore, when designing
the industrial catalysis for this reaction, we can modify the surface
of catalysis support directionally, to enhance the reaction efficiency.