José M. Resa

Temperature influence on refractive indices and isentropic compressibilities of alcohol (C2–C4)+olive oil mixtures

This paper presents isentropic compressibilities and refractive indices on mixing of mixtures enclosing short aliphatic alkanols (ethanol, 1-propanol, 2-propanol and 1-butanol) with olive oil that have been measured in the temperature range from 283.15 to 298.15 K and atmospheric pressure. The values of these properties were calculated in all range of homogeneous composition, phase splitting appearing in the mixtures (ethanol or 2-propanol) with olive oil. From the mentioned properties, derived properties such as compressibility solvation numbers, isentropic apparent molar compressibility and changes of magnitudes were calculated. The enhanced packing efficiency of alcohols at low molar fractions is strongly affected by steric hindrance of aliphatic residues, although dimers or rings of alcohol molecules are formed at high concentrations when residue end of alkanol is small. Different mixing rules for refractive indices on mixing were applied, as well as the collision factor theory (CFT) formulation for isentropic compressibilities. The thermal pressure coefficients of these solvents were analysed as a function of the temperature, their shape and trend being commented upon.

Behaviour of butyl ether as entrainer for the extractive distillation of the azeotropic mixture propanone+diisopropyl ether. Isobaric VLE data of the azeotropic components with the entrainer

Abstract The behaviour of butyl ether as entrainer in extractive distillation for the rupture of the propanone+diisopropyl ether azeotropic mixture is investigated. The vapor–liquid equilibrium of each component with butyl ether has been carried out at 101.3 kPa in order to check the absence of azeotropes. Neither system showed an azeotrope. Thermodynamic consistency of the experimental data was good. The activity coefficients were correlated by means of the van Laar, Wilson, NRTL and UNIQUAC equations. UNIFAC prediction has been also used. As a final part, an experiment of extractive distillation was carried out and a composition of 0.990 in mole fraction of acetone, 0.001 of diisopropyl ether and 0.009 of butyl ether resulted in the head of the column. In conclusion, butyl ether is an excellent solvent for the rupture of the studied azeotropic mixture.

Mixing properties of propyl acetate+aromatic hydrocarbons at 298.15 K

We present experimental data of speed of sound, refractive index on mixing and density for the binaries of propyl acetate+(toluene, ethylbenzene, p-xylene, isopropylbenzene, butylbenzene, isobutylbenzene, mesitylene, or t-butylbenzene) at T=298.15 K and 1 atm, and the corresponding computed derived magnitudes (change of isentropic compressibility, change of refractive index on mixing, and excess molar volume). The mixtures show a clear expansive tendency for the highest molar weight compounds, and the steric hindrance role of the aromatic chemicals was analyzed to the light of the non ideality on mixing. Values of physical properties were compared with the results obtained by theoretical estimation procedures.

Excess molar volumes of binary mixtures containing vinyl acetate + alkyl acetates at 298.15 K. Anomalous behavior of methyl acetate + vinyl acetate mixtures

Abstract Excess molar volumes for binary mixtures containing vinyl acetate + methyl acetate, +ethyl acetate, +propyl acetate, +isopropyl acetate, +butyl acetate, +isobutyl acetate, +pentyl acetate, +isopentyl acetate have been determined from density measurements at 298.15 K using an Anton Paar DMA 58 vibrating tube densitometer. A maximum in densities has been observed for the methyl acetate + vinyl acetate system, where samples with different composition showed the same density. Excess molar volumes increase with an increase of the size of the second acetate.

Isobaric vapor-liquid equilibria of acetone-propyl ether and isopropyl ether-propyl ether systems. Corroboration of no reverse volatility

Abstract Isobaric vapor - liquid equilibria were determined at 101.325 kPa for binary mixtures containing acetone + isopropyl ether, acetone + propyl ether and isopropyl ether + propyl ether using a dynamic still with vapor and liquid circulation. The azeotrope of the system acetone + isopropyl ether is in agreement with the literature value and none of the other systems shows an azeotrope. The thermodynamic consistency of the experimental data was checked by Van Nesss test and Heringtons criterion modified by Wisniak and they satisfied our data. The activity coefficients were correlated using the Wilson model and the UNIFAC prediction. In the final part of the work, an experiment for extractive distillation is described on a laboratory scale and the results confirmed that there is no reversal of volatility of this system.

Excess Volumes for Binary Mixtures Formed by Methyl Acetate with Aromatic Hydrocarbons

Excess molar volumes for binary mixtures containing methyl acetate + methylbenzene, ethylbenzene, 1,4-dimethylethylbenzene, 1-methylbenzene, 1,-3,-5-trimethylbenzene or 1,-1-dimethylethylbenzene were determined from density measurements at 298. 15 K using an Anton Paar DMA 58 vibrating tube densitometer. The excess molar volumes were positive throughout the concentration ranges. The excess molar volumes increase with the size of the hydrocarbon.

Mixtures formed of alkyl acetates with olive oil at 298.15 k

Enthalpies of mixing and heat capacities of the systems formed of alkyl acetates (ethyl acetate, propyl acetate, isopropyl acetate, butyl acetate and isobutyl acetate) with olive oil were measured at 298.15 K. The mixing of acetates with the oil was strongly endothermic, and the highest measured enthalpies per mole of mixture were 2000 J mol-1 for ethyl acetate at an acetate mole fraction of 0.6. The heat capacities of the mixtures were calculated too and values were decreasing as the mole fraction of acetate increases and varied from 296 to 3929 J K-1 mol-1.