Experimental solubility curve and tie-line data were obtained for a ternary system of water, phosphoric acid, and 1-undecanol at T = 303. 2 K and ambient pressure. The cloud point method was employed to determine the binodal curve data. The mass fraction compositions of each layer were explored by acid-base and the Karl Fisher titration methods accompanied by mass balance calculations. For the mentioned ternary system, a type-1 LLE behavior was observed. The reliability of the experimental compositions was verified using the Othmer-Tobias and Hand plots. The UNIQUAC and NRTL thermodynamic models were applied to correlate the equilibrium tie-line points. The experimental points were adequately regressed using the thermodynamic models. Distribution coefficients and separation factors were computed over the non-miscible region. For the separation process, separation factor should be greater than one. For the present system, this separation factor was suitable to apply separation treatment in all concentrations of phosphoric acid at the experiment temperature. The Katritzky parameters were utilized for LSER modeling of distribution coefficients of the target mixtures. The ternary system showed good fittings with the LSER model.

Persistent organic pollutants, (POPs), are vast distributed compounds in environment which are recognized as one of the global pollution problems. These groups of materials being dangerous due to their high stability are accumulated in animal tissues and occurring in the food chain. One of the major paths through which persistent organic combinations access to human body is consuming polluted foods, particularly, fishes. Among aquatic animals, trout as one of the mostly consumed fishes in Tehran’ s food basket was studied. In this study, two categories of persistent organic pollutants: Organochlorine pesticides (OCPs) including HCB, Dieldrin, Methoxychlor, α-, ϒ-Chlordane, α-, β-Endosulfan and o, p’-DDE, p, p’-DDE, o, p’-DDT, p, p’-DDT and the second group Polychlonitated biphenyls (PCBs) including seven PCB congeners which are caLLEd indicator PCBs (IUPAC nos.: 28, 52, 101, 118, 138, 153 and 180) were determined in trout by GC-MS/MS in MRM monitoring mode and LLE extraction. The average recoveries of OCPs and PCBs at five concentration levels (1, 2, 5, 10 and 20 ng/g for PCBs and 5 times for OCPs) were in the range of 73-112%. The relative standard deviations of POPs in fish were in the range of 1. 4-17. 9% for all of the concentration levels. The limit of detections (LODs) and the limit of quantitations (LOQs) were between 0. 6-8. 3 and 2-25 μ g/kg, respectively. The results indicated the presence of organochlorine pesticides in trout and the levels of p, p’-DDE and p, p’-DDT were within the range of < LOQ-12. 83 and < LOQ-10. 2 ng/g ww (wet weight), respectively. According to the results, OCPs residues were lower than maximum residue levels set by European Council Directives.

The effect of NaCl on the LLE data for the ternary system, water + 1-propanol + hexane, were determined at 298Kunder atmospheric pressure. The curve of solubility and tie-line data of this system were determined by experimental analysis. The experimental results showed that the addition of NaCl significantly affected the two-phase region of the ternary system, the enlargement of the two-phase region occurred with an increase of salt concentration in the initial aqueous phase. Distribution coefficients and separation factors were also calculated and compared at different NaCl concentrations. In addition, the experimental tie-line data were correlated with the NRTL model. Also, the parameters of this model were estimated with five nature-inspired metaheuristic solvers. These algorithms are Genetic Algorithms (GA), Monkey-Krill Herd Hybrid (MAKHA), Intelligent Firefly Algorithm (IFA), Cuckoo Search (CS), and Harmony Search Algorithm(HAS). The capabilities and limitations of these solvers have been analyzed. Results showed that all algorithms outperformed, in particular, MAKHA give the best efficiency-reliability for the prediction of LLE.