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    Prigogine-Flory-Patterson evaluation of systems with ionic liquids plus water or methanol: A study of specific interactions
    (Elsevier, 2018) Santos, Dheiver; Bamufleh, Hisham S.; Uslu, Hasan
    Descriptions of the assets of combinations of ionic liquids and polar compounds are very important for engineering projects. In this study, the modeling of binary systems involving different cations and anions was performed to observe the structural influence and the level of interaction with water and alcohol. The Prigogine-Flory-Patterson equation of state makes possible the evaluation of the level of interaction of the mixture through the Flory interaction contribution. The contribution through the characteristic pressure was shown to be of little relevance compared to the contributions of free volume and characteristic pressure. The binary mixtures, for the most part, showed a negative value, which demonstrates the strong interactions between ionic liquids and the studied compounds. (C) 2018 Elsevier B.V. All rights reserved.
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    Separation of 2,4,6-trinitrophenol from aqueous solution by liquid-liquid extraction method: Equilibrium, kinetics, thermodynamics and molecular dynamic simulation
    (Elsevier Science Sa, 2016) Uslu, Hasan; Datta, Dipaloy; Santos, Dheiver; Bamufleh, Hisham S.; Bayat, Cuma
    In this paper, the equilibrium and kinetic studies on the extraction of 2,4,6-trinitrophenol (picric acid) (0.021-0.061 kmol m(-3)) using Amberlite LA2, a secondary amine (ALA2: 0.118-0.588 kmol m(-3)) dissolved in a polar active solvent, methyl-iso-butyl ketone (MIBK) are performed. Also, the temperature effect (293.2 +/- 1 K, 303.2 +/- 1 K and 313.2 +/- 1 K) on the extraction mechanism and efficiency is evaluated. Thermodynamic parameters like the change in entropy and enthalpy are determined. From the values of loading ratio (Z < 0.5), it is inferred that the amine molecule form 1:1 complex with the acid molecule in the organic phase. The mass transfer coefficient (k(L), = 3.1 x 10(-5) m s(-1)) of picric acid in MIBK is determined. The Hatta number is calculated, and observed to vary in the range of 0.0032-0.0054, indicating that there is a very slow chemical reaction taking place between the acid and the amine molecule in the bulk of the organic phase. The reaction order is estimated to be 0.9 w.r.t picric acid, and 0.6 w.r.t ALA2 with rate constants of 14.95 x 10(-6) (kmol m(-3))(-0.5) s(-1), and 8.94 x 10(-7) (kmol m(-3))(-0.5) s(-1), for forward and backward reaction, respectively. Kinetic and potential energies of components during reactive extraction have been determined by molecular dynamic modeling. (C) 2016 Elsevier B.V. All rights reserved.
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    Separation of Levulinic Acid Using Polymeric Resin, Amberlite IRA-67
    (Amer Chemical Soc, 2019) Uslu, Hasan; Datta, Dipaloy; Santos, Dheiver; Öztürk, Muhsin
    The adsorptive separation of levulinic acid (LA) from its aqueous solution was studied by using a commercial adsorbent and weakly basic anion exchange resin, Amberlite IRA-67 (IRA-67). The data were generated for equilibrium and kinetic studies, and to analyze the performance of IRA-67 on the removal efficiency. The equilibrium study was performed to see the effect of adsorbent quantity (0.25-1.5 g) and initial LA concentrations (2-4 g.L-1) at three different temperatures (298, 308, and 318 K). To determine the kinetics of adsorption process, concentration profile was achieved up to a time of 90 min at 298 K. It was observed that both the intake capacity (32-64 mg.g(-1)) and removal efficiency (6.75-72.5%) of IRA-67 were increased with an increase in the quantity of adsorbent (0.25-1.5 g) at 298 K. From the kinetics of adsorption, 50 min was considered as an equilibrium time. Different isotherm and kinetic models were used to determine the equilibrium and kinetic parameters of LA adsorption process. From the temperature study (298, 308, and 318 K), the thermodynamic properties were also estimated at three different LA concentrations.