The speed of sound and density of mixtures of 1-ethyl-3-methylimidazolium trifluoromethanesulfonate ([emim][triflate]) with methanol, ethanol, 1-propanol, and water, as well as of the pure components have been experimentally measured over the whole range of compositions at T = (278.15 to 338.15) K and atmospheric pressure. From these experimental data, the excess molar volume, excess isentropic compressibility, and excess speed of sound have been calculated and fitted to an extended version of the Redlich−Kister equation, which takes into account the dependence on composition and temperature simultaneously. The Prigogine−Flory−Patterson theory has also been used to explain the behavior of these systems.

Isobaric vapor-liquid equilibria for the binary systems acetone + methanol, acetone + 1-ethyl-3-methylimidazolium trifluoromethanesulfonate ([emim][triflate]), and methanol + [emim][triflate] as well as the vapor-liquid equilibrium for the acetone + methanol + [emim][triflate] ternary system have been obtained at 100 kPa using a recirculating still. The addition of the ionic liquid to the solvent mixture produced an important salting-out effect, and the azeotrope tended to disappear for small contents of ionic liquid. The experimental binary data sets were independently fitted with the electrolyte NRTL model, and the parameters of Mock's model were estimated for each binary system. These parameters were used to predict the ternary vapor-liquid equilibrium which agreed very well with the experimental one.

Controlling the location of acid sites in zeolites can have a great impact on catalysis. In this work we face the objective of directing the location of Al into the 10R channels of ZSM-5 by taking advantage of the structural preference of B to occupy certain positions at the channels intersections, as suggested by theoretical calculations. The synthesis of B-Al-ZSM-5 zeolites with variable Si/Al and Si/B ratio, followed by B removal in a post synthesis treatment, produces ZSM-5 samples enriched in Al occupying positions at 10R channels. The location of the acid sites is determined on the basis of the product distribution of 1-hexene cracking as test reaction. The higher selectivity to propene and lower C4 = /C3 = ratio in the samples synthesized with B and subsequently deboronated can be related to a larger concentration of acid sites in 10R channels, where monomolecular cracking occurs. Finally, several ZSM-5 samples have been tested in the methanol to propene reaction, and those synthesized through the B assisted method show longer catalytic lifetime, higher propene yield and lower yield of alkanes and aromatics.

Isobaric vapor-liquid equilibria for the binary systems ethyl acetate + ethanol, ethyl acetate + 1-ethyl-3methylimidazolium trifluoromethanesulfonate ([emim][triflate]), and ethanol + [emim][triflate] as well as the vapor-liquid equilibria for the ethyl acetate + ethanol + [emim][triflate] ternary system have been obtained at 100 kPa using a recirculating still. NRTL fitting parameters for the ethyl acetate + ethanol and ethanol + [emim]-[triflate] systems were calculated. The measured ternary data were correlated using the Mock electrolyte NRTL model, which reproduces reasonably well the experimental values. The results suggest that the addition of [emim]-[triflate] to the ethyl acetate + ethanol mixture produced an important salting-out effect, and the azeotrope disappears when the mole fraction of ionic liquid in the liquid phase is greater than 0.20.

Isobaric vapor−liquid equilibria (VLE) for the binary systems methyl acetate + methanol and methyl acetate + 1-ethyl-3-methylimidazolium trifluoromethanesulfonate ([emim][triflate]) as well as the VLE for the methyl acetate + methanol + [emim][triflate] ternary system have been obtained at 100 kPa using a recirculating still. The experimental binary data sets were independently fitted with the electrolyte NRTL model, and the parameters of Mock's model were estimated for each binary system. These parameters, together with those early obtained for methanol + [emim][triflate], were used to predict the ternary VLE, which agreed reasonably with the experimental values. The results suggest that the addition of [emim][triflate] to the methyl acetate + methanol mixture produced an important salting-out effect, and the azeotrope disappears when the mole fraction of ionic liquid in the liquid phase is greater than 0.129.

Isobaric vapor-liquid equilibria for the binary systems 1-propanol + water, 1-propanol + 1-ethyl-3methylimidazolium trifluoromethanesulfonate ([emim][triflate]), and water + [emim][triflate] as well as the vapor-liquid equilibria for the 1-propanol + water + [emim][triflate] ternary system have been obtained at 100 kPa using a recirculating still. Electrolyte NRTL fitting parameters for the 1-propanol + water and water + [emim][triflate] systems were calculated. The measured ternary data were correlated using Mock's electrolyte NRTL model which reproduces reasonably well the experimental values. The results show that the addition of [emim][triflate] to 1-propanol + water produced an important salting-out effect, and the model predicts that at 100 kPa the azeotrope disappears when the mole fraction of ionic liquid in the liquid phase is greater than 0.34.

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