Selective removal of alkynes from diene mixtures using ether-functionalized Cu(i)-containing ionic liquids as
Young Jin Kim1, Hyun Ji Lee1, Yohan Ahn1
1Department of Chemistry, Kyung Hee University, 26 Kyungheedae-ro, Dongdaemun-gu, Seoul 02447, Republic of Korea. khs2004@khu.ac.kr mcheong@khu.ac.kr.
Physical Chemistry Chemical Physics : PCCP
|January 4, 2017
Summary
Copper(I)-containing room temperature ionic liquids (Cu-EnA) efficiently remove alkynes like isopropenylacetylene and 2-butyne from dienes. These Cu-EnA compounds exhibit reversible interactions, enabling selective separation and regeneration.
Area of Science:
- Materials Science
- Chemical Engineering
- Separation Science
Background:
- Ionic liquids (ILs) offer tunable properties for chemical applications.
- Separation of alkynes from dienes is crucial in petrochemical processes.
- Developing selective and recyclable separation agents is a key challenge.
Purpose of the Study:
- To synthesize and characterize novel Copper(I)-containing ionic liquids (Cu-EnA).
- To evaluate the efficacy of Cu-EnA for the selective removal of alkynes from dienes.
- To elucidate the mechanism of selective alkyne-diene separation.
Main Methods:
- Synthesis of ether-functionalized ionic liquids (EnA) and their complexation with CuCl.
- Thermal stability assessment of the synthesized Cu-EnA.
- Evaluation of separation performance for isopropenylacetylene (IPA) and 2-butyne (2-BT) from isoprene.
- Fast atom bombardment (FAB)-mass spectrometry and computational modeling (DFT) to determine the structure and interaction mechanisms.
Main Results:
- Cu-EnA were synthesized, exhibiting thermal stability.
- Cu-EnA demonstrated high effectiveness and selectivity in removing IPA and 2-BT from isoprene.
- Reversible interactions between Cu-EnA and alkynes were observed, allowing for regeneration of the ionic liquid.
- FAB-mass spectrometry and computational studies indicated the formation of methanesulfonate-coordinated Cu(I) anions.
- Computational results revealed that preferential extraction is driven by differences in hydrogen bonding and π-complexation strength.
Conclusions:
- Cu-EnA are effective and recyclable materials for the selective separation of specific alkynes from dienes.
- The separation mechanism involves selective hydrogen bonding and π-complexation interactions.
- This study presents a promising approach for alkyne purification in industrial applications.
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