Thermodynamic Properties of a New Hydrophobic Amide-Based Task-Specific Ionic Liquid [EimCH₂CONHBu][NTf₂]

Density, surface tension, dynamic viscosity, and electrical conductivity of a new air and water stable hydrophobic amide-based task-specific ionic liquid (IL) 1-butylamide-3-ethylimimdazolium bis­(trifluoromethylsulfonyl)­imide ([EimCH₂CONHBu]­[NTf₂]) were determined in the temperature range of <i>T</i> = (283 to 363) K. The volumetric and surface properties were discussed using the density and surface tension values. The thermal expansion coefficient was predicted by the interstice model theory. The decomposition temperature was determined with the thermogravimatric analysis (TG). The molar conductivity data were calculated by density and electrical conductivity values. Temperature dependence on dynamic viscosity and electrical conductivity values of the [EimCH₂CONHBu]­[NTf₂] were fitted by the VFT equation. The Arrhenius equation was also used to fit the dynamic viscosity and electrical conductivity values

Density, Electrical Conductivity, and Dynamic Viscosity of <i>N</i>‑Alkyl-4-methylpyridinium Bis(trifluoromethylsulfonyl)imide

Two air and water stable hydrophobic ionic liquids <i>N</i>-alkyl-4-methylpyridinium bis­(trifluoromethylsulfonyl)­imide ([C_<i>n</i>4mpy]­[NTf₂], <i>n</i> = 2, 4) were synthesized and characterized. The density, electrical conductivity, and dynamic viscosity were measured and estimated in the range of <i>T</i> = (278.15 to 363.15) K. The melting temperature, glass transition temperature, and decomposition temperature of the two ILs were determined according to the differential scanning calorimetry (DSC) and thermogravimetric analyzer (TG). The molecular volume, standard molar entropy, and lattice energy were estimated in terms of empirical equations on the basis of the density values. The electrical conductivity and dynamic viscosity values dependence on temperature were fitted by the Vogel–Fulcher–Tamman equation. The molar conductivity was calculated by the density and electrical conductivity

Extraction Process of Dibenzothiophene with New Distillable Amine-Based Protic Ionic Liquids

In this study, two kinds of amine-based protic ionic liquids (PILs), namely, 2-[2-(dimethylamino)­ethoxy] ethanol propionate ([DMEE]­[CO₂Et]) and 3-(dimethylamino)-propanenitrile propionate ([DMAPN]­[CO₂Et]), were introduced into the desulfurization process for the first time. Some important parameters, such as stirring speed, ionic liquid (IL) dosage, initial concentration, etc., were investigated. According to the experiments, the sulfur content in the model oil can be effectively removed from 1600 to about 650 ppm by a single extraction cycle. After five cycles, the sulfur content could reach up to 19 ppm and the deep desulfurization was achieved. Most important, the recycling of PILs was realized by vacuumed distillation. The properties and extraction efficiency of PILs have no change after recycling. At the same time, the extraction mechanisms were probed. The results show that the hydrogen bond formed between the sulfur of dibenzothiophene (DBT) and the active hydrogen of PIL accounts for the high desulfurization efficiencies. This novel process would provide a new route for extraction desulfurization of diesel fuels

Physicochemical Properties of Ionic Liquids [C₃py][NTf₂] and [C₆py][NTf₂]

Air- and water-stable hydrophobic ionic liquids <i>N</i>-alkylpyridinium bis(trifluoromethylsulfonyl)imide ([C_<i>n</i>py][NTf₂], <i>n</i> = 3, 6) were synthesized. The density, surface tension, dynamic viscosity, and electrical conductivity of [C₆py][NTf₂] were measured in the range of <i>T</i> = (283.15 to 338.15) K. The density, dynamic viscosity, and electrical conductivity of [C₃py][NTf₂] were measured in the range of <i>T</i> = (308.15 to 338.15) K. The melting and glass transition temperatures of the two ILs were determined according to the differential scanning calorimetry (DSC). The physicochemical properties, including molecular volume, standard molar entropy, lattice energy, parachor, molar enthalpy of vaporization, interstice volume, interstice fraction, and thermal expansion coefficient, were estimated in terms of empirical and semiempirical equations, as well as the interstice model theory on the base of the experimental values. The dynamic viscosity and electrical conductivity values were fitted by Vogel–Fulcher–Tammann (VFT) and Arrhenius equations for [C₆py][NTf₂] and the Arrhenius equation for [C₃py][NTf₂]