In this study, the LLE data of ternary system(water + 1,6-diaminohexane + 2-methyl-1-propanol) and(water +1,6-diaminohexane + 3-methyl-1-butanol) were measured at 293.15, 303.15 and 313.15 K under atmospheric pressure...In this study, the LLE data of ternary system(water + 1,6-diaminohexane + 2-methyl-1-propanol) and(water +1,6-diaminohexane + 3-methyl-1-butanol) were measured at 293.15, 303.15 and 313.15 K under atmospheric pressure. Reliability of the experimental tie-line data was checked by empirical Hand, Othmer-Tobias and Bachman equations. Distribution coefficient(D) and selectivity(S) were calculated in order to investigate capability of the studied organic solvents for 1,6-diaminohexane extraction. The high values of separation factors demonstrated that 2-methyl-1-propanol and 3-methyl-1-butanol were applicable for this purpose. The experimental data were correlated by nonrandom two-liquid(NRTL) and universal quasi-chemical(UNIQUAC) models.The percent-root-mean-square deviation(RMSD) values for NRTL and UNIQUAC models were less than 0.15,which indicated that the experimental data have been sufficiently correlated.展开更多
In view of the importance of solvent extraction of rare earth metals with the acidic organophosphorous reagent,the development of a chemically based model applicable to high concentration is desired.In the present stu...In view of the importance of solvent extraction of rare earth metals with the acidic organophosphorous reagent,the development of a chemically based model applicable to high concentration is desired.In the present study,the equilibrium distribution of dysprosium(Ⅲ)between an aqueous nitric acid solution and 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester (PC88A)was measured in the range of an initial aqueous dysprosium(Ⅲ)concentration from 1.0×10-3to 1.0×10-1kmol/m 3and PC88A concentration from 0.16 to 0.65 kmol/m3in Shellsol D70 as the diluent.The obtained data were analyzed using the chemically based model in order to correlate the equilibrium distribution ratios.In this model,dysprosium(Ⅲ)was assumed to be extracted with the PC88A dimer as a 1:3 complex,the activities were considered for the aqueous species,and the effective concentration of the PC88A dimer was calculated using Alstad's empirical equation.As a result,the apparent extraction equilibrium constant was determined to be 253(kmol·m- 3)-2with an excellent correlation between the experiment and calculation results in the wide range of the logarithm of the distribution ratio from-2 to 3.5.In conclusion,the methodology in this model would be effective for quantitative description of solvent extraction behavior of general rare earth elements as well as dysprosium.展开更多
In this paper we have systematically studied V-L equilibrium in ternary aqueous solutions containingvolatile electrolytes by introducing a ternary interaction term into Edwards generalized molecular thermody-namic mod...In this paper we have systematically studied V-L equilibrium in ternary aqueous solutions containingvolatile electrolytes by introducing a ternary interaction term into Edwards generalized molecular thermody-namic model and optimizing several adjustable parameters.The program PARA9 with flexible functions ofdoing a series of calculations has been developed and carried out on a TQ-16 computer.It can be usedeither for directly calculating the V-L equilibrium or for optimizing the adjustable parameters.For the sys-toms(NH3-CO3-H2O3,NH3-H2S-H2O and NH3-SO2-H2O)satisfactory results have been obtained withrelative mean deviation of 5-10%.Besides,several sets of adjustable parameters and valuable information ofactivity coefficients,equilibrium concentrations of ions and molecules in solutions are obtained.展开更多
文摘In this study, the LLE data of ternary system(water + 1,6-diaminohexane + 2-methyl-1-propanol) and(water +1,6-diaminohexane + 3-methyl-1-butanol) were measured at 293.15, 303.15 and 313.15 K under atmospheric pressure. Reliability of the experimental tie-line data was checked by empirical Hand, Othmer-Tobias and Bachman equations. Distribution coefficient(D) and selectivity(S) were calculated in order to investigate capability of the studied organic solvents for 1,6-diaminohexane extraction. The high values of separation factors demonstrated that 2-methyl-1-propanol and 3-methyl-1-butanol were applicable for this purpose. The experimental data were correlated by nonrandom two-liquid(NRTL) and universal quasi-chemical(UNIQUAC) models.The percent-root-mean-square deviation(RMSD) values for NRTL and UNIQUAC models were less than 0.15,which indicated that the experimental data have been sufficiently correlated.
基金the Japan Society for the Promotion of Science for supporting this fellowship work(No.07616)
文摘In view of the importance of solvent extraction of rare earth metals with the acidic organophosphorous reagent,the development of a chemically based model applicable to high concentration is desired.In the present study,the equilibrium distribution of dysprosium(Ⅲ)between an aqueous nitric acid solution and 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester (PC88A)was measured in the range of an initial aqueous dysprosium(Ⅲ)concentration from 1.0×10-3to 1.0×10-1kmol/m 3and PC88A concentration from 0.16 to 0.65 kmol/m3in Shellsol D70 as the diluent.The obtained data were analyzed using the chemically based model in order to correlate the equilibrium distribution ratios.In this model,dysprosium(Ⅲ)was assumed to be extracted with the PC88A dimer as a 1:3 complex,the activities were considered for the aqueous species,and the effective concentration of the PC88A dimer was calculated using Alstad's empirical equation.As a result,the apparent extraction equilibrium constant was determined to be 253(kmol·m- 3)-2with an excellent correlation between the experiment and calculation results in the wide range of the logarithm of the distribution ratio from-2 to 3.5.In conclusion,the methodology in this model would be effective for quantitative description of solvent extraction behavior of general rare earth elements as well as dysprosium.
基金supported by the USTC Research Funds of the Double First-Class Initiative(YD2090002008)the Fundamental Research Funds for the Central Universities(WK2090000032).
文摘In this paper we have systematically studied V-L equilibrium in ternary aqueous solutions containingvolatile electrolytes by introducing a ternary interaction term into Edwards generalized molecular thermody-namic model and optimizing several adjustable parameters.The program PARA9 with flexible functions ofdoing a series of calculations has been developed and carried out on a TQ-16 computer.It can be usedeither for directly calculating the V-L equilibrium or for optimizing the adjustable parameters.For the sys-toms(NH3-CO3-H2O3,NH3-H2S-H2O and NH3-SO2-H2O)satisfactory results have been obtained withrelative mean deviation of 5-10%.Besides,several sets of adjustable parameters and valuable information ofactivity coefficients,equilibrium concentrations of ions and molecules in solutions are obtained.