Prediction of critical micelle concentrations of nonionic surfactants in aqueous and nonaqueous solvents with UNIFAC

E.C. Voutsas, M.V. Flores, N. Spiliotis, G. Bell, P.J. Halling, D.P. Tassios

Research output: Contribution to journalArticlepeer-review

18 Citations (Scopus)


The UNIFAC group-contribution model is used to predict the critical micelle concentration (cmc) of nonionic surfactants in aqueous and nonaqueous solvents. For predicting the cmc, the phase-separation thermodynamic framework approach is used, where the micellar phase is approximated as a second liquid phase resulting from the liquid-liquid equilibrium between the solvent and the surfactant. The necessary activity coefficients are predicted by UNIFAC. The most promising UNIFAC model for this purpose was found to be the UNIFAC-Lyngby (Ind. Eng. Chem. Res. 1987, 26, 2274). To improve the results for surfactants containing oxyethylene chains, a new set of parameters was evaluated for this group, leading to still better cmc predictions for both water and organic solvents, as well as binary solvent systems.
Original languageEnglish
Pages (from-to)2362-2366
Number of pages4
JournalIndustrial and Engineering Chemistry Research
Issue number10
Publication statusPublished - 16 May 2001


  • Vapor liquid equilibrium
  • poly(ethylene glycols)
  • activity- coefficients
  • water
  • model
  • aggregation
  • parameter
  • mixtures
  • behavior

Cite this