A detailed investigation of the phase diagram of the mixtures of the two ionic liquids N-trimethyl-N-propylammonium bis(trifluoromethylsulfonyl)imide (TMPA-TFSI) and N-trimethyl-N-hexylammonium bis(trifluoromethylsulfonyl)imide (TMHA-TFSI) has been performed in the temperature range between 140 and 330 K by means of DSC and infrared spectroscopy measurements. In the low temperature crystalline states, a large concentration of the trans-TFSI conformer is present in TMPA-TFSI, while almost only cis-TFSI is retained in TMHA-TFSI. For the mixtures (TMPA-TFSI) (TMHA-TFSI), at concentrations close to the extremes, solid crystalline phases are still present and they show a strong predominance of the trans conformer of the TFSI ion for x < 15 or a large concentration of the cis conformer of TFSI for x > 85. At intermediate concentrations (33 < x < 67) no crystalline phase develops at low temperatures and both conformers of TFSI survive in the whole temperature range investigated here. We suggest that the competition between the two TFSI conformers at low temperatures can be the origin of the lack of crystalline phases for intermediate concentrations and can be exploited as a valid tool to tailor the physical properties of the mixtures of ionic liquids.
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Langmuir
January 2025
Institute of Chemical Technology and Engineering, Faculty of Chemical Technology, Poznan University of Technology, ul. Berdychowo 4, PL 60-965 Poznan, Poland.
Despite extensive research on the use of salts to enhance micellar growth, numerous questions remain regarding the impact of ionic exchange and molecular structure on charge neutralization. This study looks into how certain cations (Na, Ca, and Mg) affect the structure of a cocamidopropyl betaine CAPB and sodium dodecylbenzenesulfonate SDBS surfactant mixture, aiming toward applications in targeted delivery systems. The mixture consists of a zwitterionic surfactant, cocamidopropyl betaine (CAPB), and an anionic surfactant, sodium dodecylbenzenesulfonate (SDBS), combined in varying molar ratios at a total concentration of 200 mM.
View Article and Find Full Text PDFPLoS One
January 2025
Nalecz Institute of Biocybernetics and Biomedical Engineering, Polish Academy of Sciences, Warsaw, Poland.
Ion exchange membranes (IEMs) are permselective membranes that, in principle, only allow the flow of ions with a specific charge sign, opposite to that of the fixed membrane ionic groups (counter-ions). This charge-based selectivity, like the size-based selectivity of classic semipermeable membranes, leads to an uneven distribution of permeating ions on the two sides of the membrane, which allows for ion separation or recovery in various processes in industry or environmental protection. Here, we apply the principles of mass balance, charge neutrality, and equality of electrochemical potentials in the state of thermodynamic equilibrium to provide a simple method for estimating the Gibbs-Donnan factors and the equilibrium concentrations of permeating ions in two compartments separated by an ideal IEM, i.
View Article and Find Full Text PDFJ Phys Chem A
January 2025
Institute for Molecules and Materials, FELIX Laboratory, Radboud University, Toernooiveld 7, 6525 ED Nijmegen, The Netherlands.
Symmetry breaking is ubiquitous in chemical transformations and affects various physicochemical properties of materials and molecules; Jahn-Teller (JT) distortion of hexa-coordinated transition-metal-ligand complexes falls within this paradigm. An uneven occupancy of degenerate 3d-orbitals forces the complex to adopt an axially elongated or compressed geometry, lowering the symmetry of the system and lifting the degeneracy. Coordination complexes of Cu are known to exhibit axial elongation, while compression is far less common, although this may be due to the lack of rigorous experimental verification.
View Article and Find Full Text PDFSci Rep
January 2025
Military Institute of Engineering, Praça General Tibúrcio 80, Urca, Rio de Janeiro, RJ, 22290-270, Brazil.
The antiscale magnetic treatment (ASMT) claims to utilize magnetic field to combat scaling. However, its underlying mechanism, effectiveness, and reliability remain controversial. To address these contentious aspects, we analyze the influence of a magnetic field on the different stages of typical scale formation, using [Formula: see text] as a model scale.
View Article and Find Full Text PDFACS Omega
January 2025
Department of Chemical Technology, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand.
The development of stable, high-performance electrolytes is essential to addressing the safety concerns and limited lifespan caused by the thermal and chemical instability of traditional organic carbonate-based electrolytes in lithium-ion batteries (LIBs). This study examined the potential of mixed solvent systems, specifically ethyl methyl carbonate (EMC) and tetramethylene sulfone (TMS), to modify ion solvation and improve ionic conductivity in LIB electrolytes. Through molecular dynamics simulations, we investigated the solvation structure and transport properties of lithium ions (Li) in these solvent environments.
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