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کاربرد نوع شرط:
- جایگاه : پژوهشی
- مجله: Physical Chemistry Research
- نوع مقاله: Journal Article
- کلمات کلیدی: Liquid-liquid equilibrium,Lactic Acid,Thermodynamic Modeling
- چکیده:
- چکیده انگلیسی: In this study, tie-line points and solubility data were experimentally measured for the ternary mixture (water + lactic acid + diethyl ether) at T = 293.2 K and atmospheric pressure. UNIFAC calculations predicted that lactic acid and diethyl ether do not form an azeotrope. The mass fractions of organic and aqueous layers were determined by acid-base and the Karl Fisher titrations. Cloud point method verified that the LLE behavior of the studied system is Type-1. The reliability of the tie-line points was demonstrated by the Othmer–Tobias and Hand plots. Thermodynamic correlation of tie-line data was done by NRTL model and the obtained binary interaction parameters were tested after validation. The experimental and correlated data had very good accordance (rmsd = 0.88 %). Extraction quality of diethyl ether was investigated using the calculation of distribution coefficients and separation factors over the immiscibility area. Separation factors decreased from 1.93 to 1.13 when aqueous mass fraction of lactic acid increased from 0.070 to 0.305. However, distribution coefficient increased from 0.07 to 0.12 in the same region. The study shows that the extraction of lactic acid is possible in all investigated feeds at 293.2 K.
- انتشار مقاله: 05-07-1399
- نویسندگان: Sina Shekarsaraee,Abbas Naimi,Bahareh Bussary
- مشاهده
- جایگاه : پژوهشی
- مجله: Physical Chemistry Research
- نوع مقاله: Journal Article
- کلمات کلیدی: Phosphoric acid,Thermodynamic model,Liquid-liquid equilibria,HPLC method,Plait point
- چکیده:
- چکیده انگلیسی: Solubility data and tie-line points were experimentally determined for the ternary system (water + phosphoric acid + Heptyl acetate) at T = 298.2 K and ambient pressure. The cloud point method was used to measure the immiscibility region. Type-1 LLE behavior was observed for the investigated system and the plait point data were calculated using the Treybal’s method. The compositions of both aqueous and esteric layers were determined by using of acid-base titration, HPLC method and mass balance equation. The Othmer–Tobias and Hand equations were applied to prove the reliability of tie-line data. Obtained tie-line points were then correlated using the UNIQUAC model and the rmsd results showed that the measured points were satisfactorily regressed by the thermodynamic model. To evaluate the ability of the studied solvent for purification of phosphoric acid, distribution coefficients and separation factors were calculated over the biphasic area. Separation factors were greater than one in all investigated feeds of phosphoric acid for the studied system. Heptyl acetate showed the highest separation factors between all the investigated n-alkyl acetate esters.
- انتشار مقاله: 06-01-1399
- نویسندگان: Sina Shekarsaraee,Ali Ghanadzadeh Gilani,Mahrokh Pir
- مشاهده
- جایگاه : پژوهشی
- مجله: Physical Chemistry Research
- نوع مقاله: Journal Article
- کلمات کلیدی: Phosphoric acid,Liquid-liquid equilibrium,Thermodynamic model,LSER approach
- چکیده:
- چکیده انگلیسی: Experimental solubility curve and tie-line data were obtained for the ternary system (water + phosphoric acid + 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 above mentioned ternary system, a type-1 LLE behavior was observed. The reliability of the experimental compositions was proved by 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 and for the investigated system, this factor was suitable to apply separation treatment in all concentrations of phosphoric acid at the studied temperature. The Katritzky parameters were utilized for LSER modeling of distribution coefficients of the studied mixtures. The ternary system showed good fittings with the LSER model.
- انتشار مقاله: 13-11-1397
- نویسندگان: Sina Shekarsaraee,Benyamin Kolachahi Sabet,Farhad Moradi,Morteza Kazemi,Yasaman Parvandi
- مشاهده
- جایگاه : پژوهشی
- مجله: Physical Chemistry Research
- نوع مقاله: Journal Article
- کلمات کلیدی: Thermodynamic model,Solubility data,Tie-line points,Phase equilibria
- چکیده:
- چکیده انگلیسی: The purpose of this reaserch is to measure the phase equilibrium data of the ternary system (water + phosphoric acid + 1-nonanol) at different temperatures. Experimental solubility curves and tie-line points for the system were obtained at T = 298.2, 308.2 and 318.2 K and ambient pressure. The binodal curve data were detected by the cloud point method. The mass fractions of each layer were achieved by acid-base and the Karl-Fisher titration, accompanied by refractive index calibration curves. A type-1 LLE phase diagram was observed for this ternary system. The equilibrium tie-line data were correlated via the UNIQUAC and NRTL thermodynamic models. The experimental tie-lines of the studied system were satisfactorily regressed to the models. The reliability of the experimental end points was determined using the Othmer-Tobias and Hand plots. Distribution coefficients and separation factors were calculated over the non-miscible parts. For the separation process, separation factor should be greater than one. For the investigated system, the facor was suitable for separation treatment in all concentrations of phosphoric acid and three temperatures.
- انتشار مقاله: 12-11-1394
- نویسندگان: Sina Shekarsaraee,Sina Shekarsaraee,Sina Shekarsaraee
- مشاهده
- جایگاه : پژوهشی
- مجله: Physical Chemistry Research
- نوع مقاله: Journal Article
- کلمات کلیدی: Azo N-ester-1,8-naphthalimide(ANEN) dyes,Dichroic ratio,Guest-host interactions,LD and ELD parameters
- چکیده:
- چکیده انگلیسی: This research is an attempt to measure the effect of alkyl tail on the visible spectra and order parameters S of some azo N-ester-1,8-naphthalimide(ANEN) disperse dyestuff. For the first time, the visible absorption spectra of two azo N-ester-1,8-naphthalimide(ANEN) dyes with identical molecular size and diverse alkyl tails were obtained in liquids and liquid crystalline solvent. Ordinary organic solvents with different polarity and chemical nature (i.e. cyclohexane, 1,4-dioxane, tetrachloromethane, benzene, diethyl ether, chloroform, dichloromethane, 1-butanol, acetone, ethanol and methanol) accompanied by nematic liquid crystal matrix (5CB) were used. In the visible region of parallel aligned samples the intensity of the absorption bands was measured, thereby the dichroic ratios R and order parameters S of the dyes were determined. Then, the interaction of these dyes was investigated and compared with the anisotropic surroundings and those of the isotropic organic solvents. It was found that the electronic absorption spectra of the dyes in the alcoholic (methanol and/or ethanol) surroundings are shifted to red compared to that of the isotropic organic solutions. Thus, there are strong molecular interactions between the dye molecules and methanol molecules. Also, the electro-optical effects of the guest-host systems were investigated through polarized spectroscopic method.
- انتشار مقاله: 09-12-1393
- نویسندگان: Sina Shekarsaraee,Ali Ghanadzadeh
- مشاهده
- جایگاه : پژوهشی
- مجله: Advanced Journal of Chemistry-Section A
- نوع مقاله: Journal Article
- کلمات کلیدی: Phosphoric acid,Liquid-liquid equilibrium,Thermodynamic model,LSER approach
- چکیده:
- چکیده انگلیسی: In this study, experimental tie-line data analysis was conducted for the ternary system (water+phosphoric acid+1-pentanol) at 278.2 K and 288.2 K and atmospheric pressure. The compositions of equilibrium phases were determined using the acid-base and the Karl Fisher titration methods and mass balance calculations. Reliability of the experimental data was investigated using the Othmer–Tobias and Hand equations. The UNIQUAC thermodynamic model was applied for correlation of the equilibrium tie-line points. The experimental tie-lines were satisfactorily regressed using the thermodynamic model (%rmsd=2.48). Distribution coefficients and separation factors were determined over the biphasic area. Separation factors were greater than one in all the investigated feeds at the studied temperatures that guarantees the successful separation process. The Kamlet-Taft parameters were applied for the LSER modeling of the obtained distribution coefficients and separation factors. The effect of temperature on extraction process was investigated by adding a modification term in Kamlet-Taft equation. The ternary system revealed good fittings with the modified LSER model. The results showed that, the temperature decrement had positive effect on the extraction ability of the 1-pentanol for separating phosphoric acid from aqueous solution.
- انتشار مقاله: 01-08-1398
- نویسندگان: Sina Shekarsaraee,Khadijeh Kazemi
- مشاهده