Deep eutectic solvents (DES) are compounds of a hydrogen bond donor (HBD) and a hydrogen bond acceptor (HBA) that contain a depressed melting point compared to their individual constituents. DES have been studied for their use as carbon capture media and biogas upgrading. However, contaminants’ presence in biogas might affect the carbon capture by DES. In this study, conductor-like screening model for real solvents (COSMO-RS) was used to determine the effect of temperature, pressure, and selective contaminants on five DES’ namely, choline chloride-urea, choline chloride-ethylene glycol, tetra butyl ammonium chloride-ethylene glycol, tetra butyl ammonium bromide-decanoic acid, and tetra octyl ammonium chloride-decanoic acid. Impurities studied in this paper are hydrogen sulfide, ammonia, water, nitrogen, octamethyltrisiloxane, and decamethylcyclopentasiloxane. At infinite dilution, CO2 solubility dependence upon temperature in each DES was examined by means of Henry’s Law constants. Next, the systems were modeled from infinite dilution to equilibrium using the modified Raoults’ Law, where CO2 solubility dependence upon pressure was examined. Finally, solubility of CO2 and CH4 in the various DES were explored with the presence of varying mole percent of selective contaminants. Among the parameters studied, it was found that the HBD of the solvent is the most determinant factor for the effectiveness of CO2 solubility. Other factors affecting the solubility are alkyl chain length of the HBA, the associated halogen, and the resulting polarity of the DES. It was also found that choline chloride-urea is the most selective to CO2, but has the lowest CO2 solubility, and is the most polar among other solvents. On the other hand, tetraoctylammonium chloride-decanoic acid is the least selective, has the highest maximum CO2 solubility, is the least polar, and is the least affected by its environment.
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Chiral Eutectic Mixtures and Deep Eutectic Solvents for Induced Circularly Polarized Luminescence
Deep eutectic solvents (DES) or eutectic mixtures prepared with a chiral component can lead to new chiral solvents with applications that include asymmetric synthesis and chiral light emitting materials. DES have low melting points, because of strong interactions, such as hydrogen bonding, between components of the mixture. Mixtures are prepared with ammonium salts, tetrabutylammonium chloride ([TBA]Cl) and choline chloride ([Ch]Cl), as hydrogen bond acceptor (HBA) and L‐lactic acid, L‐leucic acid, L‐ascorbic acid, R/S‐acetoxypropionic acid, and methyl‐(S)‐lactate as chiral hydrogen bond donors (HBD). Eight combinations of the HBAs and HBDs were prepared, and a racemic mixture of dissymmetric chiral europium complexes was dissolved in the mixtures. The circularly polarized luminescence (CPL) spectra were measured to determine the chiral discrimination by these chiral solvents. The CPL spectra show that the handedness of the chiral HBD is important to the chiral discrimination exhibited. However, the inversion of the sign of the CPL spectra in 1 : 3 [TBA]Cl:L‐lactic acid vs. 1 : 3 [Ch]Cl:L‐lactic acid, and 1 : 1.5 [Ch]Cl:L‐leucic acid vs. 1 : 1 [TBA]Cl:L‐leucic acid shows that the achiral HBA also plays a critical role in the handedness of the chiral discrimination by the chiral solvent.
more » « less- Award ID(s):
- 1800269
- NSF-PAR ID:
- 10306730
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- ChemPhotoChem
- Volume:
- 5
- Issue:
- 12
- ISSN:
- 2367-0932
- Page Range / eLocation ID:
- p. 1071-1078
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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