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: firstname.lastname@example.org
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 studies1-5. 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
1. Zhang SJ, Sun J, Zhang XC, Xin JY, Miao QQ, Wang JJ. Ionic liquid-based green processes for energy production. Chemical Society Reviews, 2014, 43: 7838-7869
2. Cheng WG, Chen X, Sun J, Wang JQ, Zhang SJ. SBA-15 supported triazolium-based ionic liquids as highly efficient and recyclable catalysts for fixation of CO2 with epoxides. Catalysis Today, 2013,200: 117- 124
3. Sun J, Wang JQ, Cheng WG, Zhang JX, Li XH, Zhang SJ, She YB. Chitosan functionalized ionic liquid as a recyclable biopolymer-supported catalyst for cycloaddition of CO2. Green Chemistry, 2012, 14: 654-660
4. Wang JQ, Sun J, Cheng WG, Dong K, Zhang XP, Zhang SJ. Experimental and theoretical studies on hydrogen bond-promoted fixation of carbon dioxide and epoxides in cyclic carbonates. Phys. Chem. Chem. Phys. 2012, 14: 11021- 11026.
5. Xu BH, Wang JQ, Sun J, Huang Y, Zhang JP, Zhang SJ. Fixation of CO2 into cyclic carbonates catalyzed by ionic liquids: a multi-scale approach. Green Chemistry, 2015, 17: 108-122.
See more of this Group/Topical: Topical Conference: Innovations of Green Process Engineering for Sustainable Energy and Environment