Liquid–liquid equilibria for aqueous sulfuric acid solutions with undecane, dodecane, or 1-dodecanol, trioctylamine or tributyl phosphate and excess and deviation properties for sub-binary systems at 298.15 K

The psuedo ternary LLE data are reported for the following systems at 298.15 K: an aqueous sulfuric acid solution (ASS) + dodecane + tributylphosphate (TBP); an ASS + 1-dodecanol + TBP; an ASS + undecane + TBP; an ASS + dodecane + trioctylamine (TOA); an ASS + 1-dodecanol + TOA and an ASS + undecane + TOA. These experimental LLE data were correlated well with the non-random two-liquid (NRTL) GE model. In addition, the density (ρ) and the refractive index (nD) for the systems {TBP + dodecane}, {TBP + 1-dodecanol}, {TBP + undecane}, {TOA + dodecane}, {TOA + 1-dodecanol} and {TOA + undecane} at 298.15 K were determined. These data were used to calculate the binary excess molar volumes (VE) and the deviations of the refractive indices (ΔR) over the entire composition range. The experimental data were satisfactorily fitted using the Redlich–Kister polynomial.

► Molybdenum compounds are used in high-pressure and high-temperature applications. ► Liquid–liquid equilibria at 298.15 K for TOA, TBP contained ternary systems. ► Excess and deviation properties for sub-binary systems. ► NRTL model was used for the correlation of the determined LLE data. ► The VE and ΔR data were correlated well with the Redlich–Kister polynomial.