Water Activity and Phase Equilibria Measurements ... - ACS Publications

Oct 6, 2017 - Haijun HanXiang JiJunjie MaZhifeng XuLijiang GuoDongdong LiYan Yao. Journal of Chemical & Engineering Data 2018 63 (5), 1636-1641...
1 downloads 0 Views 419KB Size
Article pubs.acs.org/jced

Water Activity and Phase Equilibria Measurements and Model Simulation for the KCl−SrCl2−H2O System at 323.15 K Haijun Han,*,†,‡ Lijiang Guo,‡,§ Dongdong Li,‡ and Yan Yao‡ †

School of Metallurgy and Chemical Engineering, Jiangxi University of Science and Technology, Ganzhou 341000, P. R. China Qinghai Institute of Salt Lakes, Chinese Academy of Sciences, Xining 810008, P. R. China § Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, P. R. China ‡

ABSTRACT: Water activities for the ternary system of KCl−SrCl2−H2O and its sub-binary system SrCl2−H2O were elaborately measured using an isopiestic method at 323.15 K. The solubility isotherms for the KCl−SrCl2−H2O system were determined by the isothermal equilibrium method. It is found that the measured isopiestic composition lines for the KCl−SrCl2−H2O system deviated from the Zdanovskii rule, especially at a lower water activity. The Pitzer−Simonson−Clegg model was used to correlate the measured water activity and solubility data, simulate the thermodynamic properties, and predict the solubility of the ternary system. The reliability of the solubility data measured in this work was evaluated by comparing with the solubility isotherms calculated with the Pitzer−Simonson−Clegg model. The measured water activity and solubility results are of great importance for predicting the phase diagram of other multicomponent systems that related to this ternary system. ternary system KCl−SrCl2−H2O from 290.15 to 387.15 K. Filippov et al.8 and Shi et al.9 reported the phase diagram for the ternary system KCl−SrCl2−H2O at 298.15 K, and the results are consistent with each other. Zhang et al.10 reported the phase equilibria for the titled system at 323.15 K. Li et al.11 reported the experimental solubility of the KCl−SrCl2−H2O system at 348.15 K. These above experimental results indicate that the ternary KCl−SrCl2−H2O system has one invariant point KCl(s) and SrCl2·nH2O(s) (n will decrease with increasing temperature). Meng et al.12 reported the isothermal evaporation process simulation on the system LiCl−NaCl−KCl− SrCl2−H2O (CaCl2 is not included) using the Pitzer model at 298.15 K. Since there is no reported water activities of the KCl−SrCl2−H2O system at 323.15 K, we have no idea if the isopiestic composition lines at constant water activity obey the Zdanovskii rule or will deviate the Zdanovskii rule like the KCl−Mg(Ca)Cl2−H2O systems at 323.15 K, which are investigated and discussed in our previous work.13,14 As a continuing study of our work, the water activity and solubility for the ternary system KCl−SrCl2−H2O at 323.15 K are measured, respectively. This work is useful for parametrizing a thermodynamic model for a multicomponent system at multiple temperatures. The Pitzer−Simonson−Clegg (PSC) model was used to correlate the experimental water activity data and solubility and represent the thermodynamic properties and calculating the solubility isotherms, which will help us

1. INTRODUCTION There are abundant strontium, potassium, lithium, iodine, and other high value-added element resources in Nanyishan oilfield brine, which located in the Qaidam Basin of China. At present, the research works related to separating and extracting these valuable elements from oilfield brine are carried out with the exploitation of oilfields. According to the main compositions, the Nanyishan oilfield brine can be roughly summarized as the LiCl−KCl−NaCl−CaCl2−SrCl2−H2O system. The thermodynamic properties and solubility of this multicomponent system and its sub-binary systems at different temperatures are of great importance for extracting high valued resources from the brine and realizing the comprehensive exploration and utilization of the oilfield brine. As the subternary system of this above complex system, the phase diagram, thermodynamic properties, and model on KCl−SrCl2−H2O system are very helpful for constructing phase diagram of this above complex system. About the phase diagram and thermodynamic properties on the KCl−SrCl2−H2O system are reported by the following authors. Rard and Miller1,2 reported the water activities for the aqueous SrCl2 and NaCl−SrCl2−H2O systems by isopiestic method using CaCl2(aq) as the reference solution at 298.15 K. Clegg, Rard, and Miller3 reported the osmotic and water activity of NaCl−SrCl2−H2O system by the isopiestic method using NaCl(aq) as a reference at 298.15 K. Guo et al.4,5 reported the isopiestic measured water activity results of ternary systems LiCl−SrCl2−H2O and CaCl2−SrCl2−H2O using H2SO4(aq) and NaCl(aq) as the reference solution at 298.15 K. Partanen6 reevaluated the mean activity coefficients of aqueous SrCl2 from 283.15 to 333.15 K and at 298.15 K up to saturated concentration. Assarsson7 reported the solubility data of this © XXXX American Chemical Society

Received: June 1, 2017 Accepted: September 27, 2017

A

DOI: 10.1021/acs.jced.7b00492 J. Chem. Eng. Data XXXX, XXX, XXX−XXX

Journal of Chemical & Engineering Data

Article

Table 1. Reagents Used in This Worka reagents potassium chloride strontium chloride hexahydrate sulfuric acid barium chloride dihydrate sodium tetraphenylborion silver nitrate a

source Sinopharm Chemical Reagent Sinopharm Chemical Reagent Beijing Chemical Works Sinopharm Chemical Reagent Sinopharm Chemical Reagent Sinopharm Chemical Reagent

initial mass fraction purity

purification method

final mass fraction purity

analysis method

>0.998 >0.998 >0.9995 >0.995 >0.990 >0.9995

recrystallization recrystallization none none none none

0.9999 0.9999 0.9995 0.9970 none none

ICP ICP ICP ICP

Co. Co. Co. Co. Co.

The impurity of the chemical agents were determined in this work, and the purity basis is mass.

is 4−7 μm) as a filter was used for pumping liquids into a 25 cm3 weighing bottle with more than 10 g. To prevent the salts from crystallizing out of the solution in the sampling process, the temperature around the bath and the sampling appliance temperature were adjusted near that of the baths before sampling. The compositions of every solution and wet solid phase were determined by analyzing the concentrations of K+, Sr2+, and Cl−. The K+ concentration was determined by the method of sodium tetraphenylborion, as described in the literature.15 The Cl− concentration was determined using the precipitation method with AgNO3 (99.95%), as described in the literature.15 The Sr2+ concentration was determined gravimetrically by precipitating with ammonium carbonate solution, as described in the literature.16

deeply understand the thermodynamic properties of these systems.

2. EXPERIMENTAL SECTION 2.1. Materials. The water obtained by deionization and double distillation with a conductance of less than 1.5 × 10−4 S· m−1 was used for all sample purifications, preparations, and dilutions in the experiment. KCl and SrCl2·6H2O (Sinopharm Chemical Reagent Co. Ltd., G. R. grade) were purified by three recrystallizations, and the impurities of salts, such as Li, Na, K, Mg, Ca, Sr, and Fe, were analyzed to be less than 0.01%. The content of the KCl and SrCl2 stock solutions for isopiestic measurement were determined using the precipitation method15 with AgNO3 (99.95%) as a precipitating agent. H2SO4 (Beijing Chemical Works, G. R. grade) was diluted as isopiestic reference without further purification and its content was determined by a precipitation method15 with BaCl2 (Sinopharm Chemical Reagent Co. Ltd., G. R. grade) as a precipitating agent. The largest relative deviation of the analysis for each of three parallel samples was below 0.05%. The impurities in the salts were also analyzed by ICP emission spectrometry (Thermo Electron Corporation, ICAP 6500 DUO). Table 1 shows the characteristics of the chemical samples used in this work. 2.2. Apparatus and Procedures. The water activity isopiestic measurements were carried out using the setup as described in our previous work13,14 and will show no more details here. Solubility phase equilibrium measurements were performed in a thermostatic bath controlled by a thermostat (LAUDA E219, Germany) with a temperature stability of ±0.01 K. The bath equilibrium temperature was recalibrated by a precision digital display thermal resistance thermometer (tested by Chinese National Institute of Metrology) with an accuracy of ±0.001 K. An electronic balance (Sartorius, CPA225D, 220 g capacity and 0.01 mg resolution within 110 g) was used for weighing. The solid phases were identified with an X-ray diffractometer (X’pert PRO, Spectris. Pte. Ltd., The Netherlands). The solid−liquid phase equilibrium of the samples was carried out in a glass ground flask with 150 cm3 capacity immersed in the thermostatic bath of the thermostat at 323.15 K. The solid−liquid samples prepared in the glass ground flask were stirred with a constant speed calibrated by a magnetic stirrer placed under the bath. The equilibrium time of the titled system was 7 days. The solution composition was analyzed after the system equilibrium time reached 7 days. When equilibrium time reached, the solid−liquid equilibrium solution was let stand for about 12 h. Then, the solutions and wet solid phases were sampled and analyzed. A pipet covered glass cloth G4 (aperture

3. EXPERIMENTAL RESULTS 3.1. Reference Solutions. H2SO4(aq) was used as an isopiestic reference solution. The osmotic coefficients of the Table 2. Fitted Parameters for eq 1 for H2SO4a parameters

H2SO4 (0−6m)

a b c d e f g h σb

0.75482 −0.64330 1.41025 −1.52740 1.01590 −0.36632 0.06689 −0.00485 8.7576 × 10−4

a

Fitting the osmotic coefficients of H2SO4 in the literature.17

b

Standard deviation, σ =

1 n

n

∑i = 1 (ϕ(exp) − ϕ(calc))2 .

pure H2SO4 solutions17 were used to fit as a function of molality (m) using eq 1. ϕ = a + b(m)0.5 + c(m) + d(m)1.5 + e(m)2 + f (m)2.5 + g (m)3 + h(m)3.5

(1)

where a, b, c, d, e, f, g, and h are empirical parameters. The obtained parameters for the H2SO4 reference solutions are given in Table 2. The osmotic coefficients of the other solutions investigated in this study were calculated using eq 2 as

ϕ= B

v*m*ϕ* ∑i vm i i

(2) DOI: 10.1021/acs.jced.7b00492 J. Chem. Eng. Data XXXX, XXX, XXX−XXX

Journal of Chemical & Engineering Data

Article

Table 3. Experimental Isopiestic Molality m and Calculated Water Activities aw of the Ternary System KCl−SrCl2−H2O at 323.15 K and 0.1 MPaa no.

mSrCl2 (mol·kg−1)

mKCl (mol·kg−1)

no.

mSrCl2 (mol·kg−1)

mKCl (mol·kg−1)

1

mH2SO4 = 0.6161

aw = 0.9779 ± 0.0010

4

mH2SO4 = 3.7439

aw = 0.8090 ± 0.0008

2

0.4652 0.4326 0.3592 0.2785 0.1817 0.0666 0 mH2SO4 = 1.4933

0 0.0479 0.1552 0.2764 0.4182 0.5951 0.6874 aw = 0.9407 ± 0.0009

5

2.6931 2.5773 2.2930 1.9095 1.3483 0.5305 0 mH2SO4 = 4.8512

0 0.2856 0.9905 1.8947 3.1025 4.7432 5.7038 aw = 0.7308 ± 0.0007

1.1173 1.0509 0.8964 0.7108

0 0.1164 0.3872 0.7053

6

3.4573 3.3324 3.0082 mH2SO4 = 5.9773

0 0.3692 1.2994 aw = 0.6483 ± 0.0006

0.4757 0.1762 0 mH2SO4 = 2.7324

1.0947 1.5752 1.8399 aw = 0.8741 ± 0.0009

4.2647 4.1312

0 0.4577

1.9953 1.8976 1.6598 1.3558 0.9366 0.3596 0

0 0.2103 0.7170 1.3453 2.1550 3.2153 3.8192

3

a

Water activity is calculated by the eqs 1 and 3 with the parameters in Table 2. The uncertainty for the water activity is absolute uncertainty. m, molality, moles per kilogram of solvent (pure water in this work). The relative standard uncertainty is ur(m) = 0.003, u(T) = 0.03 K, and ur(p) = 0.1.

Table 4. Experimental Solubility Data for the Ternary System KCl−SrCl2−H2O at 323.15 K and 0.1 MPaa composition of the solution (100 w) no.

KCl

H2O

SrCl2

1 2 3 4 5 6 7 8 9 10 11 12

30.10 27.57 14.01 23.50 12.08 19.21 9.34 7.13 7.12 6.45 2.99 0.00

69.90 69.23 63.18 67.71 61.22 65.82 58.13 53.62 53.63 53.88 56.26 57.94

0.00 3.20 22.82 8.79 26.69 14.97 32.53 39.25 39.25 39.67 40.74 42.06

Figure 1. Experimental isopiestic lines compared with the line of Zdanovskii rule in the KCl−SrCl2−H2O system at 323.15 K. Dashed lines, Zdanovskii rule; filled circles connected by solid line, experimental values.

where the quantities by asterisks (*) represent the reference solution, ν* = 3 denotes the number of ions formed by the complete dissociation of one molecule of H2SO4, m* is the isopiestic equilibrium molality of the reference solution, ϕ*is the osmotic coefficient of the reference solution, and ∑iνimi = 2mKCl + 3mSrCl2 for the ternary KCl−SrCl2−H2O system. The water activities aw of the reference solution were calculated using eq 3: ln a w = −vM w mϕ

composition of the wet solid phase (100 wb) KCl

H2O

SrCl2

47.63 32.82 41.80 32.25 40.30 24.34 5.79

50.17 49.01 51.53 46.78 48.54 48.14 45.67

2.20 18.17 6.66 20.96 11.16 27.52 48.53

3.00 1.29

46.56 47.11

50.44 51.59

solid phasec A A A A A A A A+B A+B B B B

a

The standard uncertainties u are ur(w) = 0.002, u(T) = 0.03 K, and ur(p) = 0.1. bw: mass fraction. cA: KCl(s), B: SrCl2·6H2O(s).

3.2. Isopiestic Measurements. The experimental water activities for the KCl−SrCl2−H2O system of at 323.15 K are presented in Table 3. In each isopiestic experimental run, the molalities (mol·kg−1) and water activity of the reference solution (H2SO4(aq)) are listed in the first line. The isopiestic molalities of the pure or mixed solutions are listed from the second line. During each isopiestic measurement run, the largest relative molality difference between two duplicate samples was ±0.3%, which can be attributed to total weighing errors, the equilibrium time, water transportation within the

(3)

where ν is the number of ions assumed to be produced when a salt dissociates completely, that is, ν = 3 for SrCl2, and ν = 2 for KCl. Mw (kg·mol−1) is the molar mass of H2O, and ϕ is the osmotic coefficient of the reference solution. C

DOI: 10.1021/acs.jced.7b00492 J. Chem. Eng. Data XXXX, XXX, XXX−XXX

Journal of Chemical & Engineering Data

Article

has far deviated from the ideal solution with increasing ionic strength. 3.3. Solubility Measurements. For the ternary system KCl−SrCl2−H2O, the measured solubility data at 323.15 K are presented in Table 4 and plotted in Figure 2. The equilibrium solid phases in this system were determined by Schreinemaker’s method18 and powder X-ray diffraction. The identified equilibrium solid phases in the ternary system are KCl and SrCl2·6H2O as shown in Figure 3. As shown in Figure 2, the phase diagram of the titled system at 323.15 K consists of two simple salt crystallization regions corresponding to SrCl2·6H2O and KCl. The crystallization field of the salt KCl is larger than SrCl2·6H2O. These results show that the KCl solid phase is easier crystallized than SrCl2·6H2O from the solution at 323.15 K.

4. MODELING The thermodynamic model contributes to profound understand phase diagrams and properties of aqueous system. To

Figure 2. Isothermal solubility curve for the system KCl−SrCl2−H2O at 323.15 K. All experimental data are in this work; ●, saturated solution composition; ○, wet solid phase composition.

Table 6. Solubility Product Parameters ln Kosp at 323.15 K substance

ln Kosp

sources

KCl SrCl2·6H2O

−5.4856 −6.7778

this work this work

Figure 3. X-ray diffraction pattern of the invariant point (KCl + SrCl2· 6H2O) of the system KCl−SrCl2−H2O at 323.15 K.

isopiestic chamber, and temperature differences between the two cups. Combining the 0.1% uncertainty associated with impurities and the 0.3% uncertainty described above, it is reasonably concluded that the total uncertainty of the measured salt molality should be less than 0.4%, which corresponds to a greatest possible deviation in the measured water activities of ±0.0026. The experimentally measured isopiestic results for the ternary system KCl−SrCl2−H2O at 323.15 K are shown in Figure 1. As shown in Figure 1, isopiestic composition points in the KCl−SrCl2−H2O system at low ionic strength are found to exist in a roughly straight line. It indicates that the mixture behavior of this ternary system at low ionic strength is approximately the ideal solution. However, similar to the ternary systems KCl−Mg(Ca)Cl2−H2O and differing from the ternary systems NaCl−Mg(Ca)Cl2−H2O in our previous work,13,14 the isopiestic composition lines for the KCl− SrCl2−H2O system were found to deviate from the Zdanovskii rule line (dashed lines in Figure 1) high with the increasing ionic strength of the solution. It means that the mixing solution

Figure 4. Solubility isotherm comparison of experimental and predicted by the Pitzer model of the system KCl−SrCl2−H2O at 323.15 K. All symbols are experimental data: ■, expt. values in this work; ●, expt. values;7 ▲, expt. values;10 ▼, expt. values.11 All lines are predicted solubility isotherms by PSC model: ---, model values with binary parameters only; , model values with binary parameters and mixture parameters.

Table 7. PSC Mixing Model Parameters of the KCl−SrCl2− H2O System at 323.15 K i

j

K

Sr

a

σ=

1 n

k

Wijk

Q1,ijk

Uijk

data for parametrization

σa

Cl

−11.49

9.83

0

aw in Table 3

0.0016

n ∑i = 1 (a w (exp)

2

− a w (calc)) .

confirm the reliability of experimental data and get more information with the solid−liquid phase equilibrium, the PSC

Table 5. PSC Model Parameters for Binary Systems at 323.15 K solute

αMX

BMX

α1MX

B1MX

W1,MX

U1,MX

V1,MX

sources

SrCl2 KCl

13 13

164.9280 5.3847

2.0 0

0 0

8.1823 −2.7595

47.3081 −1.3749

−41.4599 0

this work ref 14

D

DOI: 10.1021/acs.jced.7b00492 J. Chem. Eng. Data XXXX, XXX, XXX−XXX

Journal of Chemical & Engineering Data

Article

(4) Guo, L. J.; Sun, B.; Zeng, D. W.; Yao, Y.; Han, H. J. Isopiestic Measurement and Solubility Evaluation of the Ternary System LiCl− SrCl2−H2O at 298.15 K. J. Chem. Eng. Data 2012, 57, 817−827. (5) Guo, L. J.; Zeng, D. W.; Yao, Y.; Han, H. J. Isopiestic Measurement and Solubility Evaluation of the Ternary System (CaCl2 + SrCl2 + H2O) at T = 298.15 K. J. Chem. Thermodyn. 2013, 63, 60− 66. (6) Partanen, J. I. Re-evaluation of the Mean Activity Coefficients of Strontium Chloride in Dilute Aqueous Solutions from (10 to 60) °C and at 25 °C up to the Saturated Solution Where the Molality is 3.520 mol·kg−1. J. Chem. Eng. Data 2013, 58, 2738−2747. (7) Assarsson, G. O. Equilibria in Aqueous Systems Containing Sr2+, K+, Na+ and Cl−. J. Phys. Chem. 1953, 57, 207−210. (8) Filippov, V. K.; Fedorov, Y. A.; Charykov, N. A. Thermodynamics of Phase Equilibria in K+, Sr2+, Cl−−H2O, Na+, Sr2+, Cl−−H2O and Na+, K+, Sr2+, Cl−−H2O Systems at 25 °C. Zh. Obshch. Khim. 1990, 60, 492−497. (9) Shi, L. J.; Sun, B.; Ding, X. P.; Song, P. S. Phase Equilibria in Ternary System KCl−SrCl2−H2O at 25 °C. Chin. J. Inorg. Chem. 2010, 26, 333−338. (10) Zhang, X.; Sang, S. H.; Zhong, S. Y.; Huang, W. Y. Equilibria in the Ternary System SrCl2−KCl−H2O and the Quaternary System SrCl2−KCl−NaCl−H2O at 323 K. Russ. J. Phys. Chem. A 2015, 89, 2322−2326. (11) Li, D. W.; Sang, S. H.; Cui, R. Z.; Wei, C. Solid−Liquid Equilibria in the Ternary Systems NaCl−SrCl2−H2O and KCl− SrCl2−H2O at 348 K. J. Chem. Eng. Data 2015, 60, 1227−1232. (12) Meng, L. Z.; Gruszkiewicz, M. S.; Deng, T. L.; Guo, Y. F.; Li, D. Isothermal Evaporation Process Simulation Using the Pitzer Model for the Quinary System LiCl−NaCl−KCl−SrCl2−H2O at 298.15 K. Ind. Eng. Chem. Res. 2015, 54, 8311−8318. (13) Han, H. J.; Li, D. D.; Guo, L. J.; Yao, Y.; Yang, H. T.; Zeng, D. W. Isopiestic Measurements of Water Activity for the NaCl−KCl− MgCl2−H2O Systems at 323.15 K. J. Chem. Eng. Data 2015, 60, 1139−1145. (14) Han, H. J.; Guo, L. J.; Li, D. D.; Dong, O. Y.; Yao, Y.; Zhang, N.; Zeng, D. W. Isopiestic Determination of Water Activity on the Systems MCl−CaCl2−H2O (M = Na, K) at 323.15 K. J. Chem. Eng. Data 2015, 60, 2285−2290. (15) Kolthoff, M.; Sandell, E. B.; Meehan, E. J. Quantitative Chemical Analysis; Macmillan: New York, 1969. (16) Ji, X.; Han, H. J.; Li, D. D.; Guo, L. J.; Zeng, D. W. Gravimetric Analysis of Calcium and Strontium in Calcium and Strontium Chloride System. Metall. Anal. (in Chinese) 2016, 36, 26−30. (17) Pitzer, K. S. Activity Coefficients in Electrolyte Solutions; CRC: Boca Raton, 1991. (18) Schreinemakers, F. A. H. Graphical Deductions from the Solution Isotherms of a Double Salt and Its Components. Z. Phys. Chem. 1893, 11, 75−109.

model is chosen to represent the properties of this ternary system KCl−SrCl2−H2O in this work. Generally, the PSC model with the parameters in Table 5 is sufficient to represent the properties of the binary system KCl− H2O in our previous work.14 For the binary parameters of SrCl2, we get them by fitting the determined water activities in this work. To calculate the phase diagram of titled ternary system, the solubility products for all single salt solid phase are needed in advance. The solubility products were obtained andare listed in Table 6. Applying the binary parameters in Tables 5 and 6 of the ternary system, we predicted directly the solubility isotherms and found that the calculated isotherms (dashed lines in Figure 4) deviate greatly from the experimental data in this work and the literature.7,10 Therefore, the mixing parameters Wmnx, Qmnx, and Umnx must be used. The ternary mixture parameters Wmnx, Qmnx, and Umnx were only fitted by the experimental water activities (Table 3) determined in this work and listed in Table 7. Applying the binary and mixing model parameters in Tables 5, 6, and 7, we recalculated the solubility isotherms of the titled ternary system at 323.15 K. The calculated values (solid lines in Figure 4) are in agreement with the solubility data in this work.

5. CONCLUSIONS We elaborately measured the water activities of the ternary system KCl−SrCl2−H2O and its sub-binary system at 323.15 K using the isopiestic method. The isopiestic composition lines in the KCl−SrCl2−H2O system showed positive deviations from the Zdanovskii rule. The solid−liquid equilibrium diagram of the ternary system KCl−SrCl2−H2O at 323.15 K was determined by the isothermal method. The PSC model was used for simulating the thermodynamic properties and predicting the solubility isotherms of the titled ternary system at 323.15 K. The predicted solubility isotherms and experimental values determined in this work of the titled ternary system agree with each another very well.



AUTHOR INFORMATION

Corresponding Author

*E-mail: [email protected]. ORCID

Haijun Han: 0000-0003-1345-6544 Lijiang Guo: 0000-0002-1018-4646 Funding

The authors gratefully thank the National Natural Science Foundation of China (grants 21406253 and 21303239) for financial support of this work. Notes

The authors declare no competing financial interest.



REFERENCES

(1) Rard, J. A.; Miller, D. G. Isopiestic Determination of the Osmotic and Activity Coefficients of Aqueous CsCl, SrCl2, and Mixtures of NaCl and CsCl at 25 °C. J. Chem. Eng. Data 1982, 27, 169−173. (2) Rard, J. A.; Miller, D. G. Isopiestic Determination of the Osmotic and Activity Coefficients of Aqueous Mixtures of NaCl and SrCl2 at 25 °C. J. Chem. Eng. Data 1982, 27, 342−346. (3) Clegg, S. L.; Rard, J. A.; Miller, D. G. Isopiestic Determination of the Osmotic and Activity Coefficients of NaCl + SrCl2 + H2O at 298.15 K and Representation with an Extended Ion-Interaction Model. J. Chem. Eng. Data 2005, 50, 1162−1170. E

DOI: 10.1021/acs.jced.7b00492 J. Chem. Eng. Data XXXX, XXX, XXX−XXX