(418e) Synergistic Catalytic Effect in the Synthesis of Cyclic Carbonates Based on Ionic Liquids

Synergistic
Catalytic Effect in the Synthesis of Cyclic Carbonates Based on Ionic Liquids

Suo-Jiang Zhang , Wei-Guo
Cheng

Key Laboratory of Green Process and Engineering,
Institute of Process Engineering, Chinese Academy of Sciences, P.O. Box
353, Beijing, 100190, China

*Corresponding author: sjzhang@home.ipe.ac.cn

Carbon dioxide released annually to the atmosphere at ca. 30
000 Mt1 is also an attractive C1 feedstock as it is nontoxic, abundant,
inexpensive. From the viewpoint of environmental protection and resource
utilization, it is important to transform CO₂ into cyclic carbonates efficiently not only in
academia but also in industrial applications(Scheme 1). Many scientists have made a
concentrated effort to improve the performance of the ionic liquids (ILs)
catalysts during the past decade due to their tunable structures. Synergistic
catalytic effects of ILs catalytic system play an important role of promoting
the cycloaddition reactions of epoxides. However, due to the diversity of
different anion¨Ccation combinations it is difficult to make generalizations
about synergistic effects.

Scheme 1 Fixation CO₂ and epoxides into cyclic carbonates

In this
work, we have investigated the synergistic effect in the catalytic system based on ILs through experimental and theoretical studies^1-5. The results show that metal and ionic liquids, cations and anions
of ionic liquids, the functional groups in cations or supports all have a
synergistic effect on the cycloaddition reactions. Synergistic catalytic
effects of ILs play an important role of remarkably reducing the activation
energy and promoting ring-opening of epoxide. The design of catalytic system of
ionic liquids can be possible as the synergistic effect on a molecular level is
understood by using density functional theory (DFT) studies and in situ
characterization. Significant developments in IL catalysts design and optimal
process development for the synthesis of cyclic carbonates have been made with
the possible prediction of the synergetic effect based on ILs.

Keywords: synergistic effect,  ionic liquid, carbon
dioxide, cyclic carbonate, process

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