No abstract

In this work, the solubility of carbon dioxide, CO 2 , in pentaerythritol tetrapentanoate (PEC5) and in pentaerythritol tetra(2-ethylhexanoate) (PEBE8) has been performed from (283 to 333) K and pressures up to 7 MPa in a new high-pressure gas solubility apparatus. The results show that in the present analyzed range CO 2 is highly soluble in these oils and that the solubility expressed as CO 2 mole fraction is practically not dependent on the branching of the acid chain, whereas it increases slightly with the length of the PE acid chains in the present range of compositions. The gas solubility data were satisfactorily correlated with the Soave-Redlich-Kwong (SRK) equation of state (EOS) using the conventional quadratic mixing rule with two interaction parameters for each temperature.

Vapor−liquid equilibrium accompanied with chemical reaction in the quaternary water + 2-propanol + acetic acid + isopropyl acetate system was measured in a modified Dvorak and Boublík still. In total, 63 experimental points at 353.15 K and 16 points at 101.325 kPa were determined. The experimental data were correlated by means of the maximum likelihood procedure by using the NRTL model. Binary model parameters for the four nonreacting binary subsystems were obtained from available experimental vapor−liquid equilibrium data by using either the Hayden−O'Connell or Marek−Standart correction as appropriate, to account for the nonideality of the vapor phase. NRTL parameters for the water + isopropyl acetate and 2-propanol + acetic acid systems were estimated from the global optimization based on the quaternary data. The results obtained from the correlation show a good agreement of calculated and experimental data. By using transformed composition variables, three-dimensional phase diagrams for the quaternary system have been constructed and a possible location of a saddle reactive azeotrope was found.

The experimental densities of binary mixtures of cyclopentanone with 1,1,2,2-tetrachloroethane, 1,1,1-trichloroethane, trichloromethane, 1,2-dichloroethane, 1,3-dichloropropane, 1,4-dichlorobutane, and 1-chlorobutane have been measured at T = (288.15, 298.15, 308.15, and 318.15) K and atmospheric pressure, over the whole composition range. From these results, excess molar volumes, V E, have been calculated and fitted to the Redlich−Kister polynomial equation. The excess molar volumes are negative for the cyclopentanone + 1,1,2,2-tetrachloroethane, 1,1,1-trichloroethane, trichloromethane, and 1-chlorobutane systems and positive for the other three systems over almost the whole mole fraction range and temperatures studied. The variation of these properties with composition of the binary mixtures is discussed in terms of molecular interactions between components and structural effects.

No abstract