Thermodynamics of Textile Dyes Partitioning in Alcohol‐Based Aqueous Two‐Phase Systems

Abstract The aim of this work was a complete thermodynamic study on the partitioning of Remazol Yellow l, Remazol Brilliant Blue, and Remazol Red dyes in isopropyl alcohol + sodium phosphate + water aqueous two‐phase systems at different temperatures. The free energy change of transfer, enthalpy change of transfer, and entropy change of transfer were evaluated. The effects of the structure of the dye, tie line length, and temperature on the partitioning were studied. The results indicate that these aqueous two‐phase systems have high capacity to extract the dyes from aqueous matrices to the organic phase of these systems and are an interesting alternative to effluent treatment process.