The distribution of polar organic compounds typical of water contaminants (organic acids, alcohols, and aromatic compounds) associated with oil and gas production was measured between water and nine hydrophobic, room‐temperature ionic liquids. The ionic liquids used in this study were 1‐butyl‐3‐methylimidazolium bistrifluoromethanesulfonylimide, 1‐hexyl‐3‐methylimidazolium bistrifluoromethanesulfonylimide, 1‐octyl‐3‐methylimidazolium bistrifluoromethanesulfonylimide, 1‐butyl‐3‐methylimidazolium hexafluorophosphate, trihexyltetradecylphosphonium bistrifluoromethanesulfonylimide, 1‐butyl‐1‐methyl‐pyrrolidinium bistrifluoromethanesulfonylimide, trihexyltetradecylphosphonium dodecylbenzenesulfonate, tributyltetradecylphosphonium dodecylbenzenesulfonate, and trihexyltetradecylphosphonium methanesulfonate. Sensitivity of the distribution coefficients to salinity, temperature, concentration, and pH was investigated. Partitioning into the ionic liquid varied considerably. Acetic acid did not significantl...

The potential of room‐temperature ionic liquids for use in chemical separations was assessed, particularly for liquid–liquid extraction. The solubility, surface tension, and electrical conductivity of a range of imidazolium‐based ionic liquids in aqueous solution were measured at room temperature and atmospheric pressure as functions of ionic‐liquid, sodium chloride, and potassium–chloride concentrations. Hydrophobic ionic liquids were studied, including 1‐C _n ‐3‐methylimidazolium cations, C _n mim⁺, with alkyl substitutions of varying chain length, where C _n =C₂ (ethyl), C₄ (butyl), C₆ (hexyl), and C₈ (octyl), in combination with bis(trifluoromethanesulfonyl)imide, NTf₂ ⁻, and bis(perfluoroethanesulfonyl)imide, BETI⁻, anions. Hydrophilic compounds were also studied, with bromide anions and C _n mim⁺ and 1‐C _n ‐2, 3‐methylimidazolium, C _n bmim⁺, cations, where C _n =C₁₂, C₁₄ and C₁₆ are solids at room temperature, and C _n =C₈, C₉, and C₁₀ are liquids.

In the present study a reduced chemical reaction mechanism for biodiesel surrogate fuel was developed and validated for multi-dimensional engine combustion simulations. An existing detailed methyl butanoate mechanism that contained 264 species and 1219 reactions was chosen to represent the oxygenated portion of the fuel. The reduction process included flux analysis, ignition sensitivity analysis, and optimization of reaction rate constants under constant volume conditions. The current reduced mechanism consists of 41 species and 150 reactions and gives predictions in excellent agreement with those of the comprehensive mechanism. In order to validate the mechanism under biodiesel-fueled engine conditions, it was combined with another skeletal mechanism for n-heptane oxidation. This combined reaction mechanism can be used to adjust the energy content of the fuel, and account for diesel/biodiesel blend engine simulations. The combined mechanism, ERC-bio, contains 53 species and 156 reactions. Biodiesel-fueled engine operation was successfully simulated using the ERC-bio mechanism.

A computational study using multi-dimensional CFD modeling was performed to investigate the effects of physical properties on diesel engine combustion characteristics with bio-diesel fuels. Properties of typical bio-diesel fuels that were either calculated or measured are used in the study and the simulation results are compared with those of conventional diesel fuels. The sensitivity of the computational results to individual physical properties is also investigated, and the results provide information about the desirable characteristics of the blended fuels. The properties considered in the study include liquid density, vapor pressure, surface tension, liquid viscosity, liquid thermal conductivity, liquid specific heat, latent heat, vapor specific heat, vapor diffusion coefficient, vapor viscosity and vapor thermal conductivity. The results show significant effects of the fuel physical properties on ignition delay and burning rates at various engine operating conditions. It is seen that there is no single physical property that dominates differences of ignition delay between diesel and bio-diesel fuels. However, among the 11 properties considered in the study, the simulation results were found to be most sensitive to the liquid fuel density, vapor pressure and surface tension through their effects on the mixture preparation processes.