The group contribution method Modified UNIFAC (Dortmund) is a well-known mo
del for the reliable prediction of phase equilibria (VLE, LLE, SLE of eutec
tic systems, azeotropic data and gamma(infinity)) and excess properties (h(
E)). Compared to the original UNIFAC method, Modified UNIFAC (Dortmund) pro
vides a much better description of the temperature dependence of the activi
ty coefficients, and a more reliable presentation of the real behavior of p
hase equilibria in the dilute region; in addition, it also leads to better
results for asymmetric mixtures (i.e., those involving molecules of very di
fferent size). Nevertheless, the parameters published previously sometimes
give poor results, especially at high (>140 degrees C) and low (<0 degrees
C) temperatures. To overcome these weaknesses, solid-liquid equilibria (SLE
) of eutectic systems and enthalpies of mixing (h(E)) at high temperatures
have been included additionally in the database used for fitting the requir
ed group interaction parameters in order to ensure reliable results at low
and high temperatures. This paper contains details of 78 new or revised pai
rs of group interaction parameters for Mod. UNIFAC (Do) covering a large te
mperature range.