3 research outputs found
Extraction of Naphthenic Acid from Highly Acidic Oil Using Hydroxide-Based Ionic Liquids
The isolation and recovery of naphthenic
acid from highly acidic
model oil was performed using hydroxide-based ionic liquids. An extremely
low ionic liquid/oil ratio was used to completely deacidify the model
oil. Tetraalkylammonium and tetraalkylphosphonium hydroxide ionic
liquids were employed in this study. Tetraalkylammonium-based ionic
liquids are more efficient than tetraalkylphosphonium-based ionic
liquids. The recyclability of the ionic liquids for the extraction
of naphthenic acid was also studied. The regeneration of the extracted
naphthenic acid was achieved
Evaluation of Thermophysical Properties of Imidazolium-Based Phenolate Ionic Liquids
Thermophysical properties of imidazolium-based
phenolate ionic
liquids (ILs) were investigated over a wide temperature range. Different
alkyl groups such as ethyl, butyl, hexyl, octyl, and decyl were tethered
to the 1-methylimidazolium cation to study the effect of alkyl chain
length on thermophysical properties such as density, viscosity, refractive
index, heat capacity, and surface tension. The thermal stability of
the phenolate ILs was investigated using thermogravimetric analysis.
From the experimental values of density and surface tension, the molecular
volume, standard molar entropy, lattice energy, surface entropy, and
surface enthalpy of the ILs were calculated at 303.15 K
DataSheet1_Ionic liquid electrolyte selection for high voltage supercapacitors in high-temperature applications.DOCX
Systematic analyses of electrolyte physicochemical properties are important to screen ionic liquids (ILs) and understand the electrochemical performance of supercapacitor electrolytes. This study harmonizes the evaluation of electrochemical performance and transport properties of eight shortlisted ILs from 22 commercially available hydrophobic ILs toward achieving a ≥ 5 V supercapacitor capable of high-temperature operation (up to 353.15 K). The eight ILs are N-Propyl-N-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide ([Pyr 1, 3] [TFSI], N-Pentyl-N-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide ([Pyr 1, 5] [TFSI]), N-Propyl-N-methylpyrrolidinium bis(fluorosulfonyl)imide ([Pyr 1, 3] [FSI]), 1-Methyl-1-(2-methoxyethyl)pyrrolidinium Bis(trifluoromethanesulfonyl)imide ([Pyr 1, 102] [TFSI]), 1-Methyl-1-propylpiperidinium bis(trifluoromethanesulfonyl)imide ([Pip 1, 3] [TFSI]), 1-Methyl-1-propylpiperidinium bis(fluorosulfonyl)imide ([Pip 1, 3] [FSI]), N-Trimethyl-N-propylammonium bis(trifluoromethanesulfonyl)imide ([N 111, 3] [TFSI]), N-Trimethyl-N-hexylammonium bis(trifluoromethanesulfonyl)imide ([N 111, 6] [TFSI]). The density, viscosity, and ionic conductivity of the eight ILs were measured between 278.15 and 373.15 K to confirm the effects of temperature and ion structure before electrochemical characterization. The [FSI]-based ILs ([Pip 1, 3] [FSI] and [Pyr 1, 3] [FSI]) showed lower densities and viscosities compared to other ILs among the eight based on [TFSI]. Consequently, the highest conductivity was obtained for [Pyr 1, 3] [FSI]. Cyclic voltammetry and impedance spectroscopy was performed on supercapacitors assembled with the eight ILs as electrolytes between 298.15–353.15 K. Conclusion from the two-electrode supercapacitors using multi-walled carbon nanotubes showed the 6 most-applicable ILs towards the targeted ≥ 5 V SC at high temperature are [Pip 1, 3] [TFSI] (5.4 V), [Pip 1, 3] [FSI] (5 V), [N 111, 3] [TFSI] (5.1 V), [N 111, 6] [TFSI] (5.2 V), [Pyr 1, 102] [TFSI] (5.2 V), and [Pyr 1, 5] [TFSI] (5.2 V).</p