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The experimental liquid – liquid equilibrium (LLE) data for three ternary mixtures containing an ionic liquid (IL) (1-butyl-3-methyl imidazolium thiocyanate [Bmim][SCN]), alkanes ( n -hexane, n -octane and n -decane) and sulfur compound (thiophene) have been measured experimentally. Distribution and selectivity coefficients have been calculated using experimental data. The LLE data have been obtained at 25 °C and ambient pressure. The experimental LLE data of ternary mixtures have been compared with our previous works. It has been shown that the IL with higher molecular weight of cation has higher solute distribution and lower selectivity coefficients. It has been found that the solubility decreases as the cation length decreases, meanwhile ILs cation chain length has a remarkable effect on solubility of alkanes. Moreover, the experimental data have been demonstrated that the selectivity decreases as alkane chain length of alkane decreases while the solubility of alkanes in the ILs increases, hence the removal costs of aromatic sulfur components will be increased. The results show that [Bmim][SCN] has the lowest alkane solubility and highest selectivity coefficient, in the system containing n -decane and thiophene. A comparative study reveals that compared to other ILs, [Bmim][SCN] is a more suitable solvent. Finally, the experimental data have been correlated utilizing non-randomness two liquid (NRTL) model. The binary energy parameters were obtained, it can be seen that the model can correlate the experimental data efficiently. [ABSTRACT FROM AUTHOR]

In this work liquid–liquid equilibrium (LLE) data for aqueous two–phase system (ATPS) containing polyethylene glycol 6000 (PEG–6000) and Na 2 CO 3 were measured at T = (293.15, 303.15 and 313.15) K. Our results showed that increasing temperature expands the two–phase region; meanwhile large two–phase region was seen in this system which makes it applicable for industrial purposes. Experimental data were modeled using UNIQUAC, Extended UNIQUAC (E–UNIQUAC) and e–NRTL models to obtain binary interaction parameters. The model parameters were obtained using Shuffled Complex Evolution (SCE) optimization algorithm. The results showed that all studied models were in good agreement with the experimental data. Average deviation (%Δ w ) of e–NRTL, E–UNIQUAC and UNIQUAC models were 1.26, 1.37 and 3.46%, respectively. Finally in order to check the predictability of the E–UNIQUAC model, liquid–liquid equilibrium in systems containing PEG with different molecular mass (1000, 3350, 4000 and 8000) and Na 2 CO 3 were studied; It was found that liquid–liquid equilibrium data can be predicted satisfactorily using adjusted parameters in this work. [ABSTRACT FROM AUTHOR]

In this work the phase equilibrium of an aqueous two phase system (ATPS) containing polypropylene glycol (PPG, molecular weight = 425 kg·mol−1) and NaClO4 was investigated at atmospheric pressure and at 288.15 and 298.15 K. Two phase regions and composition of phases were determined. Our results show that as the temperature increases, the two-phase region expands. Also, the extended UNIQUAC (E-UNIQUAC) equation was used to correlate the equilibrium data. To reduce the number of adjustable parameters, ATPSs composed of PEG and PPG were collected from the literature and simultaneously correlated using the E-UNIQUAC model. Also, the effect of temperature on the liquid–liquid equilibrium (LLE) was considered by using temperature-dependent parameters. In the modeling, two different scenarios were supposed. In the first, polymer and salt were treated as solutes (Case A), while in the second, the pseudo-solvent approach was considered (Case B). The results showed good agreement with experimental data in both cases. The average absolute deviation of the model using Case B was about 0.2% and that for Case A was about 2% in the ATPS composed of PEG. Meanwhile, the reported errors in the ATPS containing PPG for Case A and Case B were almost equal. [ABSTRACT FROM AUTHOR]