Global phase behavior of model mixtures of water and n-alkanols

The global phase diagram (GPD) of model binary mixtures of water and n-alka nols has been determined using the statistical associating fluid theory (SA FT) equation of state (EOS). Closed regions in the two-dimensional paramete r space (the strength of the hydrogen bond of alkanol vs. the length of the alkanol molecule), where azeotropy and closed liquid-liquid immiscibility loops occur, have been found. When the diagram is transformed to the space of relative critical temperatures and volumes, no real aqueous mixture of a lkanol lies in these regions; the disagreement is caused by the choice of p arameters in this work, (C) 1999 Elsevier Science B.V. All rights reserved.