A new generation of solvents called ternary deep eutectic solvents have emerged as a promising candidate to replace ionic liquids (IL) in CO2 capturing due to its inherent advantages of both, superbase and deep eutectic solvents (DES). In this work, the binary and ternary DES were synthesized to investigate the effect of superbase on the performance of DES based membrane systems for acid gas capture. The reline DES system was chosen as binary DES and 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) was used as superbase. The ternary DES was prepared by mixing DBU in reline DES system in different molar ratios. The permeability and selectivity of the synthesized membrane for CO2, CH4, and N2 were investigated in pure and mixed gas experiments. Moreover, the effect of the DES molar ratio, operating conditions of feed on the DES based supported liquid membranes (SLMs) performance was studied comprehensively. These novel ternary DES SLMs showed significant permeability and selectivity values up to 38.12 Barrer and 58.65 respectively. These values were found to be significantly higher than the permeability and selectivity value of binary DES-SLM i.e. 31 Barrer and 51.67 respectively. The improved gas performance results of ternary DES can be attributed to the basicity and fast reaction kinetics of the superbase/DBU. The ternary DES can potentially alternate the ILs and commonly used binary DESs in CO2 capturing process due to their high affinity towards CO2 gas.
Bibliographical noteFunding Information:
Dr. A. L. Khan would like to thank Pakistan Science Foundation (PSF), Pakistan for their grant # PSF/Res/P-CIIT/Engg (124). We would also like to acknowledge Global Challenge Research Fund (GCRF-QR-11650033) for the collaborative work done with Teesside University.
Dr. A. L. Khan would like to thank Pakistan Science Foundation (PSF), Pakistan for their grant # PSF/Res/P-CIIT/Engg (124). We would also like to acknowledge Global Challenge Research Fund ( GCRF-QR-11650033 ) for the collaborative work done with Teesside University.
© 2021 The Author(s)