DETERMINATION OF PHASE COMPOSITIONS FROM PHASE-VOLUME MEASUREMENTS IN THREE-PHASE SYSTEMS OF SURFACTANT, OIL AND WATER

Abstract

The tietriangle lever rule inversion method has been used to measure the compositions of the three coexisting liquids in ternary surfactant/oil/water systems. In our simplified use of this method, phase volumes are the only measurements required for calculation of the phase compositions.

A different method of estimating phase compositions is introduced in this work to improve the statistical treatment of scatter in the data. The tietriangle lever rule is applied utilising multiple regression theory. This allows all the data to be analyzed simultaneously, not in groups of three as has been done in previous work.

The systems studied were C₁₂H₂₅(OC₂H₄)₆OH//n-C₁₂H₂₆/H₂O; C₁₂H₂₅(OC₂H₄)₆OH/n-C₁₆H₃₄/H₂O, C₁₂H₂₅(OC₂H₄)₇OH/n-C₁₂H₂₆/H₂O, and C₁₂H₂₅(OC₂H₄)₇OH/n C₁₆H₃₄/H₂O.