ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Comparison of the equations expressing phase equilibriums

J. Dykyj and P. Kľúčovský

Research Institute for Petrochemistry, Nováky

Abstract: Hala's two equations for relative volatility, α = (1 + a1'x1)/(b0' + b1'x1)(I) and α = A1' + A1'x1 + A2'x12(II), were compared with Wohl's 3 equations for mol. supplemental free mixing enthalpy: α = (exp10)(1 + a1x1)/(b0 + b1x1 (III), α = (exp10)-(A0 + A1x12) (IV), and α = (expt10){K + [(AB2X22 - A2Bx12)/(Ax1 + Bx2)2}} (V). As a criterion for accuracy this equation was chosen: Δ = [(1/n) Σni=1 δi2]1/2, where n is the no. of the measurements and δ is the difference between the exptl. and the measured relative volatilities. Eleven examples of liquid-vapor (5 isothermic and 6 isobaric) equil. show that the exptl. data were best reproduced by equation III; less exactly by equation II. Equations I and II were less exact than III, but the difference was small.

Full paper in Portable Document Format: 161-2a10.pdf (in Slovak)

Chemical Papers 16 (1-2) 10–19 (1962)