Phase Equilibria in the Aqueous Ternary Systems (NaCl + NaBO2 +

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Phase Equilibria in the Aqueous Ternary Systems (NaCl + NaBO2 + H2O) and (Na2SO4 + NaBO2 + H2O) at 298.15 K and 0.1 MPa Shangqing Chen, Mengxue Wang, Jiayin Hu, Yafei Guo,* and Tianlong Deng

J. Chem. Eng. Data Downloaded from pubs.acs.org by UNIV OF SOUTH DAKOTA on 11/10/18. For personal use only.

Tianjin Key Laboratory of Marine Resources and Chemistry, Tianjin University of Science and Technology, College of Chemical Engineering and Materials Science, Tianjin, 300457, PR China ABSTRACT: With the isothermal dissolution equilibrium method and wet-residue method, the solubility data as well as physicochemical properties including density, refractive index, and pH value of the two ternary systems (NaCl + NaBO2 + H2O) and (Na2SO4 + NaBO2 + H2O) at 298.15 K and 0.1 MPa have been experimentally determined, and the relatively phase diagrams have been established for the first time. In the ternary system (NaCl + NaBO2 + H2O), two invariant points, three univariant curves, and three crystallization regions corresponding to sodium chloride (NaCl), sodium metaborate tetrahydrate (NaBO2·4H2O), and a congruent double salt teepleite (NaCl·NaBO2·2H2O) were detected. While in the ternary system (Na2SO4 + NaBO2 + H2O), there are one invariant point, two univariant curves, and two crystallization regions corresponding to NaBO2·4H2O and mirabilite (Na2SO4·10H2O). The physicochemical properties (density, refractive index, and pH value) in the two systems present a regular variation versus that with the changes of sodium metaborate concentration in the solution. Moreover, on the basis their empirical equations, the calculated values of refractive index and density are consistent with the experimental data. been little discussion concerning the solubility data for BO2−. For instance, the ternary systems (NaCl + NaBO2 + H2O) and (Na2SO4 + NaBO2 + H2O) are fundamental subsystems of the complex component system (Li+, Na+, K+, Mg2+//Cl−, SO42−, borate−H2O), and the phase equilibria of the two systems at 298.15 K have not yet been reported in the literature until now. Herein, the solubilities and the physicochemical properties of the two ternary systems (NaCl + NaBO2 + H2O) and (Na2SO4 + NaBO2 + H2O) at 298.15 K are presented in this paper for the first time.

1. INTRODUCTION Boron and its compounds are one of the most advanced modern materials, showing great theoretical and practical significance in permanent magnetic, superconductors, boron-based fuel-rich propellants, and other fields.1 With increasing industrial demand and drying up solid ores, salt lake brine, underground water, and geothermal caches with high concentration of boron resources are universally accepted as the most promising sources of raw-materials for borates exploitation. In western China, especially the Qaidam Basin, the concentration of borates (calculated by B2O3) is even more than 3 g/L, which is of great exploitation potential and strategic importance.2,3 Generally, the composition of brine consists of complex components (Li+, Na+, K+, Mg2+//Cl−, SO42−, borate−H2O). To effectively exploit borates from borate-containing salt-water systems, the essential physicochemical processes occurring in brines, such as evaporation and crystallization, ought to be systematically researched. Therefore, it is strategically important to engage research on the phase equilibria and phase diagrams of boratecontaining brines, which play an important role in describing the aforementioned behaviors in brines.4,5 Aiming to guide industrial processes and establish complex brine system theory, the phase equilibria and phase diagrams of some borate-containing systems, such as (Li+, Na+, K+//Cl−, B4O72−−H2O), (Li+, Na+, K+//B4O72−−H2O) and (Li+, Na+, Mg2+//B4O72−−H2O) in the temperature range from 273.15 to 348.15 K, have already been reported.6−8 Because of the flexibility of the coordination number of boron, there are several kinds of borates, including metaborate (BO2−), tetraborate (B4O72−), pentaborate (B5O82−), hexaborate (B6O102−), and so on.9 So far, however, reports are mainly focused on the phase equilibria of borates with the form of B4O72−, and there has © XXXX American Chemical Society

2. EXPERIMENTAL SECTION Apparatus. To keep the system at a stationary temperature of 298.15 K, a magnetic stirring thermostatic bath (HXC-5006A, Beijing Fortune Joy Science Technology Co., Ltd.) with a temperature precision of ±0.1 K was used. The equilibrium solid phases were identified with the X-ray powder diffractometer equipped with Cu Kα radiation over a 2θ range of 10−70° and an X-ray power of 36 Kv/20 mA per scan (MSAL XD-3, Beijing Purkinje General Instrument Co., Ltd., China) combined with the wet-residue solid phase method (i.e., Schreinemarker rule, in other words, the position of the composition point of solid phase is located in the cross of the extension line when solid−liquid equilibrium reached). Reagents. The chemicals used in this work were recrystallized before use and are shown in Table 1. The fresh CO2free doubly deionized water (DDW) with a conductivity less Received: August 14, 2018 Accepted: October 31, 2018

A

DOI: 10.1021/acs.jced.8b00715 J. Chem. Eng. Data XXXX, XXX, XXX−XXX

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Table 1. Regents Used in This Work regentsa

grade

initial mass fraction purity

purification method

final mass fraction purity

analysis method

NaCl Na2SO4·10H2O NaBO2·4H2O

A.R. A.R. A.R.

0.99 0.99 0.99

recrystallization recrystallization recrystallization

0.995 0.995 0.998

titration for Cl− gravimetric method for SO42− gravimetric method for BO2−

a

Supplied by the Sinopharm Chemical Regent Co., Ltd.

Table 2. Solubilities, Densities and Refractive Indices in the Binary Subsystems (NaCl + H2O), (Na2SO4 + H2O), and (NaBO2 + H2O) at 298.15 K and 0.1 MPaa binary system NaCl + H2O

Na2SO4 + H2O

NaBO2 + H2O

solubility (100wb) 26.37 26.31 26.48 26.45 22.08 21.97 21.97 21.90 21.4 22.5 22.0 22.59

solid phase

ρ/g·cm−3

-c 1.1984 1.19810 Na2SO4·10H2O 1.211 1.2083 1.2057 1.20485 NaBO2·4H2O 1.26780 NaCl

nD

ref

1.3809 1.3796 1.3626 1.3872

11 12 13 this work 13 13 13 this work 14 15 16 this work

Figure 1. Phase diagram of the ternary system (NaCl + NaBO2 + H2O) at 298.15 K and 0.1 MPa. (●) liquid phase; () isotherm curve; (▲) wet-solid phase. Nb, sodium metaborate tetrahydrate, NaBO2·4H2O; Te, teepleite, NaCl·NaBO2·2H2O; Ha, halite, NaCl.

a

Standard uncertainties u are u(T) = 0.1 K, u(p) = 0.005 MPa; u(w) for NaCl and NaBO2 are 0.0036 and 0.00058 in mass fraction and u(x) for nD, ρ, and pH are 0.0003, 0.5 mg·cm−3, and 0.003 in this work. bw, in mass fraction. c-, not detected.

prepared and loaded in well-sealed polyethylene bottles. Subsequently, the bottles were placed into the magnetic stirring thermostatic bath at a stationary temperature of (298.15 ± 0.1) K with a stirring speed of 150 rpm. In a certain interval, the magnetic stirring was paused for about 1 h to take the clarified supernatant for chemical analysis. It was generally recognized that equilibrium was achieved when the composition of the liquid supernatant became constant, and it often takes about 30 days to reach equilibrium. Once the equilibrium was achieved, the magnetic stirring was stopped. Until the upper liquid became clarified, it was quantitatively removed for chemical

than 1 × 10−4 S m−1 and pH 6.60 at 298.15 K was used to prepare the series of artificial synthesized complexes and for chemical analysis. Experimental Methods. The experimental method has been described previously.6 The isothermal dissolution equilibrium method along with the wet-residue solid phase identification method (i.e., Schreinemarker rule) was adopted to investigate the solid−liquid phase equilibria. Primarily, a series of complexes with different ratios of crystallized salts were

Table 3. Solubilities and Physicochemical Properties of the Ternary System (NaCl + NaBO2 + H2O) at 298.15 K and 0.1 MPaa physicochemical properties composition of liquid phase (100wb)

composition of wet solid phase (100w)

ρ/g·cm−3

nD

No.

NaCl

NaBO2

H2O

NaCl

NaBO2

H2O

expt

calc

relative error, %

expt

calc

relative error, %

pH

solid phasec

1, A1 2 3 4 5, E1 6 7 8 9 10, E2 11 12 13, B1

0.00 2.91 5.67 9.70 12.54 12.69 15.80 18.02 21.77 23.48 23.80 24.73 26.45

22.59 21.30 19.02 17.23 17.13 16.82 12.54 9.50 6.84 5.57 5.37 3.22 0.00

77.41 75.79 75.31 73.07 70.33 70.49 71.66 72.48 71.39 70.95 70.83 72.05 73.55

-d 3.86 4.84 -

29.03 32.07 -

67.11 63.09 -

30.29 50.56 -

5.37 3.84 -

64.34 45.60 -

1.3872 1.3884 1.3895 1.3930 1.3981 1.3968 1.3919 1.3882 1.3876 1.3880 1.3882 1.3846 1.3796

1.3877 1.3898 1.3892 1.3921 1.3971 1.3966 1.3916 1.3880 1.3883 1.3882 1.3883 1.3847 1.3798

−0.04 −0.10 0.02 0.06 0.07 0.02 0.02 0.01 −0.05 −0.02 −0.01 −0.01 −0.02

1.26780 1.27097 1.27662 1.29149 1.30966 1.30953 1.27601 1.25625 1.24682 1.24623 1.25040 1.22643 1.19810

1.27130 1.27965 1.27308 1.28463 1.30909 1.30611 1.27487 1.25323 1.25037 1.24830 1.24842 1.22787 1.20047

−0.27 −0.68 0.28 0.53 0.04 0.26 0.09 0.24 −0.28 −0.17 0.16 −0.12 −0.20

12.910 12.717 12.289 12.214 11.973 11.845 11.754 10.706 10.968 10.088 5.962

Nb Nb Nb Nb Nb + Te Te Te Te Te Te + Ha Ha Ha Ha

a

Standard uncertainties u are u(T) = 0.1 K, u(p) = 0.005 MPa. u(w) for NaCl and NaBO2 are 0.0036 and 0.00058 in mass fraction. u(x) for nD, ρ, and pH are 0.0003, 0.5 mg·cm−3, and 0.003, respectively. bw, in mass fraction. cNb, sodium metaborate tetrahydrate, NaBO2·4H2O; Te, teepleite, NaCl·NaBO2·2H2O; Ha, halite, NaCl. d-, not detected. B

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Figure 2. X-ray patterns of the invariant points in the ternary system (NaCl + NaBO2 + H2O) at 298.15 K. (a) E1 (NaCl·NaBO2·2H2O + NaBO2· 4H2O); (b) E2 (NaCl + NaCl·NaBO2·2H2O).

in mass fraction.10 The BO2− and SO42− concentrations were analyzed by gravimetric methods with standard uncertainty of ±0.0005 in mass fraction.10 The concentration of Na+ was calculated via ion balance and also evaluated through measurement by inductively coupled plasma optical emission spectrometer (ICP-OES, Prodigy, Leeman Corporation, America) with an uncertainty of ±0.005 in mass fraction. In addition, the densities (ρ) were measured by the automatic oscillating U-tube densimeter (DMA 4500, Anton Paar, Austria) with standard uncertainty ±0.5 mg·cm−3. The refractive indices (nD) were measured by the Abbe refractometer (Abbemat 550, Anton Paar, Austria) with standard uncertainty ±0.0003, and pH values were determined by a high precision pH meter (PH-7310, WTW Co., Ltd., Germany) with

analysis. For equilibrium solid phase identification, the coexisting equilibrium residue solid phases were sampled with a specific polytetrafluoroethylene spoon. Then the wet residues were approximately evaluated by the combined chemical analysis and further identified with X-ray diffraction. As to XRD identification, a dustless filter was used to absorb the adherent mother liquor in the residues first, and the residues were washed with a small amount of ethanol. The ethanol was removed from the filter by suction. Finally, the wet residue sample was identified by XRD. Meanwhile, physicochemical properties (density, refractive index, and pH value) were determined, and the solid samples were identified. Analytical Methods. The concentration of Cl− was determined by titrimetric analysis with an uncertainty within ±0.003 C

DOI: 10.1021/acs.jced.8b00715 J. Chem. Eng. Data XXXX, XXX, XXX−XXX

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double salt teepleite is a congruent solubility double salt. Therefore, this ternary system belongs to congruent double salt type. The areas of the crystallization regions are decreased in the order of Te > Nb > Ha. Besides, the concentration of NaBO2 in the solution gradually decreased with the increasing NaCl concentration, indicating NaCl has a salting-out effect on NaBO2. A comparison on the phase diagrams of the ternary system (NaCl + NaBO2 + H2O) at 298.15 K (this work) and 308.15 K (in the literature)17 is shown in Figure 3. It was found that the crystallization area of Nb is decreased obviously with the increasing temperature, while those of Ha and Te are slightly decreased. In view of the boundary system (NaCl + H2O) and (NaBO2 + H2O), the solubilities of the single salts of NaCl and NaBO2 are increased with the increasing temperature, namely the temperature has a positive effect on their solubilities. Figure 4 shows the relationships between physicochemical properties including density, refractive index, and pH value

Figure 3. Comparison of phase diagram of the ternary system (NaCl + NaBO2 + H2O) at 298.15 and 308.15 K;17 (-●-), phase diagram at 298.15 K (in this work); (-△-), phase diagram at 308.15 K (in the literature); Nb, sodium metaborate tetrahydrate, NaBO2· 4H2O; Te, teepleite, NaCl·NaBO2·2H2O; Ha, halite, NaCl.

standard uncertainty ±0.003. All data on physicochemical properties at 298.15 ± 0.1 K in this study were measured in triplicate, and the averages were used.

3. RESULTS AND DISCUSSION To evaluate and test the reliability of the experimental method in this work, the results of the solubilites, densities, and refractive indices in the boundary subsystems (NaCl + H2O), (Na2SO4 + H2O) and (NaBO2 + H2O) at 298.15 K were compared with those in the literature11−16 and the results are summarized in Table 2. The results show that the experimental results in this work agree well with previous reports, demonstrating that our experimental procedure and results are rational and reliable. Phase Diagram of the Ternary System (NaCl + NaBO2 + H2O). The experimental results on the solubilities and relevant physicochemical properties of the ternary system (NaCl + NaBO2 + H2O) at 298.15 K are presented in Table 3, and the phase diagram based on the solubility data are plotted in Figure 1. It is worth mentioning that the composition points of wet-residues, corresponding equilibrium liquid phase, and pure solid phase must be co-lined (Schreinemarker rule), so that the composition points of the solid phase can be located in the cross point by connecting and lengthening the equilibrium liquid points and their relatively wet-residues points. In Figure 1, there are two invariant cosaturation points E1 (NaBO2·4H2O + NaCl·NaBO2·2H2O) and E2 (NaCl + NaCl· NaBO2·2H2O), three univariant solubility curves A1E1, E1E2, and B1E2, which are saturated with sodium metaborate tetrahydrate (NaBO2·4H2O, Nb), teepleite (NaCl·NaBO2·2H2O, Te) and halite (NaCl, Ha), and three crystallization regions corresponding to Nb, Te, and Ha, respectively. The solubilities of single salts of NaCl and NaBO2 in the liquid phase with mass fraction corresponding to 100w(NaBO2) = 22.59 (A1) and 100w(NaCl) = 26.45 (B1) are shown. Point E1 represents the cosaturated invariant point of (Nb + Te) with the composition of 100w(NaCl and NaBO2) of 12.54 and 17.13. At invariant point E2 (Te + Ha), the composition in the liquid phase in 100w(NaCl and NaBO2) is 23.48 and 5.57. The X-ray diffraction patterns of the equilibrium solid phase of invariant points E1 and E2 were given in Figure 2. Because there is the intersect with E1E2 when connecting the composition points of pure water and the location point of double salt teepleite (Te),

Figure 4. Diagrams of the physicochemical properties versus concentration of sodium metaborate for the ternary system (NaCl + NaBO2 + H2O) at 298.15 K: (a) density vs 100w(NaBO2); (b) refractive index vs 100w(NaBO2); (c) pH value vs 100w(NaBO2).

versus the concentration of sodium metaborate in the ternary system (NaCl + NaBO2 + H2O) at 298.15 K. The varying trend of the densities in Figure 4a is approximately the same with that of the refractive indices in Figure 4b. Both of them at first increase at curve B1E2, and the decrease at invariant point E2, then increase at E2E1 and decrease at E1A1 with the maximum values of 1.30966 g·cm−3 and 1.3981 at invariant point E1. However, the trend of pH values in Figure 4c is quite different with the aforementioned physicochemical properties, and the pH values increased monotonically except for the invariant point E2. Phase Diagram of the Ternary System (Na2SO4 + NaBO2 + H2O). The solubilities and physicochemical D

DOI: 10.1021/acs.jced.8b00715 J. Chem. Eng. Data XXXX, XXX, XXX−XXX

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Table 4. Solubilities and Physicochemical Properties of the Ternary System (Na2SO4 + NaBO2 + H2O) at 298.15 K and 0.1 MPaa physicochemical properties composition of liquid phase (100wb)

composition of wet solid phase (100w)

ρ/g·cm−3

nD

No.

Na2SO4

NaBO2

H2O

Na2SO4

NaBO2

H2O

expt

calc

relative error, %

expt

calc

relative error, %

pH

1, A2′ 2 3 4 5 6, E2′

0.00 5.75 9.66 13.09 18.15 22.22

22.59 19.77 18.36 16.99 15.31 14.39

77.41 74.48 71.98 69.92 66.54 63.39

-d 3.39 8.11 10.27 -

37.68 28.99 29.59 -

58.93 62.90 60.14 -

1.3872 1.3898 1.3917 1.3938 1.3971 1.3994

1.3877 1.3891 1.3913 1.3929 1.3961 1.3998

−0.04 0.05 0.03 0.06 0.07 −0.03

1.26780 1.30244 1.32680 1.34996 1.38821 1.41791

1.27130 1.29770 1.32318 1.34401 1.38040 1.41694

−0.27 0.37 0.27 0.44 0.57 0.07

12.910 12.717 12.289 12.214

7 8 9 10 11, B2′

20.72 20.73 21.13 21.46 21.90

10.32 7.22 4.94 2.17 0.00

68.96 72.05 73.93 76.37 78.10

34.82 32.51 -

3.85 3.72 -

61.33 63.77 -

1.3861 1.3821 1.3748 1.3626

1.3874 1.3797 1.3747

−0.10 0.17 0.01 −0.08

1.33040 1.30291 1.26612 1.20485

1.33835 1.29457 1.26769 1.21031

−0.59 0.64 −0.12 −0.45

11.973 11.845 11.754 10.706 10.968

1.3636

solid phasec Nb Nb Nb Nb Nb Nb + Mir Mir Mir Mir Mir Mir

a

Standard uncertainties u are u(T) = 0.1 K, u(p) = 0.005 MPa. u(w) for Na2SO4 and NaBO2 are 0.0057 and 0.00058 in mass fraction. u(x) for nD, ρ, and pH are 0.0003, 0.5 mg·cm−3, and 0.003, respectively. bw, in mass fraction. cNb, sodium metaborate tetrahydrate, NaBO2·4H2O; Mir, mirabilite, Na2SO4 10H2O. d-, not detected.

physicochemical properties versus the composition of sodium metaborate for the ternary system (Na2SO4 + NaBO2 + H2O) at 298.15 K are plotted in Figure 7. The refractive indices and densities in Figure 7a,b were increased obviously with the increase of NaBO2 concentration at the cosaturated region of Mir and reached maximum value of 1.3994 and 1.41791 g·cm−3 at point E2′, and then decreased after point E2′. In Figure 7c, the pH values of the solution were increased sharply before point E2′ and slightly decreased after point E2′, which reached maximum of 13.108 at invariant cosaturation point E2′. Compared to the ternary system (NaCl + NaBO2 + H2O), it can be found that the concentration of NaBO2 in the ternary system (Na2SO4 + NaBO2 + H2O) decreased more considerably with the increase of Na2SO4 concentration than NaCl, namely that the salting-out effect to NaBO2 in the ternary system (Na2SO4 + NaBO2 + H2O) was more obvious, indicating that the influence of SO42− on the binary system (NaBO2 + H2O) is stronger than Cl−, which provides the theoretical basis for the separation and purification of borates from boratecontaining brines. Calculated Density and Refractive Index. According to the following correlation equation of refractive index and density in the electrolyte solution developed previously,18 the refractive indices and densities were also calculated in this work. ρ = ∑ Ai wi ln ρ0 (1)

properties of the ternary system (Na2SO4 + NaBO2 + H2O) at 298.15 K are presented in Table 4. On the basis of the solubility data, the phase diagram is plotted in Figure 5. In the

Figure 5. Phase diagram of the ternary system (Na2SO4 + NaBO2 + H2O) at 298.15 K and 0.1 MPa. (●) liquid phase; () isotherm curve; (▲) wet-solid phase; Nb, sodium metaborate tetrahydrate, NaBO2·4H2O; Mir, mirabilite, Na2SO4 10H2O.

ternary system, there are two crystallization regions corresponding to mirabilite (Na2SO4·10H2O, Mir) and Nb (NaBO2·4H2O), two univariant solubility curves A′2E′2 and B2′E2′, and one invariant cosaturation point E2′ (Mir + Nb). Points A2′ and B2′ are two boundary sub-binary systems, representing the solubilities of two single salts 100w(NaBO2) and 100w(Na2SO4) in mass fraction at the values of 22.59 and 21.90, respectively. Point E2′ represents the invariant cosaturated points of two salts of (Mir + Nb) with the composition of 100w(Na2SO4 and NaBO2) in mass fraction of 22.22 and 14.39, respectively, and the XRD pattern is shown in Figure 6. There was no double salt and solid solution found, and the area of the crystallization region of Nb is a bit larger than that of Mir. On the basis of the experimental data (refractive indices, densities, and pH values) in Table 4, the diagrams of

ln

nD = nD0

∑ Bi wi

(2)

where ρ and ρ0 refer to the densities, nD and nD0 represent the refractive indices of the solution and the pure water at 298.15 K, respectively. The ρ0 and nD0 of pure water are 0.99704 g·cm−3 and 1.33250 at 298.15 K and 0.1 MPa.19 wi represents the ith component in the solution, expressed in mass fraction. Ai and Bi are the constants of each component in the solution calculated in this work. The density constants Ai of NaCl, Na2SO4, and NaBO2 are 0.007020, 0.008824, and 0.010757, respectively, and the refractive index constants Bi are E

DOI: 10.1021/acs.jced.8b00715 J. Chem. Eng. Data XXXX, XXX, XXX−XXX

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Figure 6. X-ray pattern of the invariant point E2′ (Na2SO4 10H2O + NaBO2·4H2O) in the ternary system (Na2SO4 + NaBO2 + H2O) at 298.15 K.

prediction, thermodynamics property calculation, and evaporating path simulation. On the basis of the Pitzer parameters and the equilibrium constants, the solubility of the systems could be calculated. Although the single-salt parameters for NaCl and Na2SO4 have been reported before, there were few discussion on that of NaBO2 and the mixing ion-interaction parameters ΘCl(SO4), BO2 and φNa, Cl(SO4), BO2. Therefore, the results obtained in this work are conducive to obtain relevant parameters, and more work on the thermodynamic data including osmotic coefficient, heat of dilution, and heat of dissolution should be proposed for further calculation.

4. CONCLUSION Phase equilibria of the ternary systems (NaCl + NaBO2 + H2O) and (Na2SO4 + NaBO2 + H2O) at 298.15 K and 0.1 MPa were studied with the isothermal dissolution equilibrium method combined with the wet-residue solid phase method. The solubilities and physicochemical properties including refractive index, density, and pH value of both systems were determined experimentally. In the ternary system (NaCl + NaBO2 + H2O), two invariant points, three univariant curves, and three crystallization regions corresponding to NaCl, NaBO2·4H2O, and double salt teepleite NaCl·NaBO2·2H2O were detected. While in the ternary system (Na2SO4 + NaBO2 + H2O), there are one invariant points, two univariant curves, and two crystallization regions corresponding to Na2SO4·10H2O and NaBO2· 4H2O. The physicochemical properties of both systems at 298.15 K changed versus the concentration of sodium metaborate in the solution. The experimental data of densities and refractive indices are consistent with the calculated values by empirical equations. Hence, the results in this work are reliable to replenish the thermodynamic parameters and can be applied in the comprehensive extraction and utilization of borate resources from brines, and enrich the database of salt−water systems.

Figure 7. Diagrams of the physicochemical properties versus concentration of sodium metaborate for the ternary system (Na2 SO 4 + NaBO 2 + H 2 O) at 298.15 K: (a) density vs 100w(NaBO2); (b) refractive index vs 100w(NaBO2); (c) pH value vs 100w(NaBO2).

0.001319, 0.001055, and 0.001797, respectively. The calculated values and relative errors are listed in Tables 3 and 4, the maximum relative errors of the density in the ternary systems (NaCl + NaBO2 + H2O) and (Na2SO4 + NaBO2 + H2O) at 298.15 K are less than 0.68%, and those for refractive index are within 0.17%, and the result indicates that the calculated values are in good agreement with the experimental data. The Pitzer ion-interaction model and its extended Harvie− Weare (HW) equations have been widely used in solubility

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AUTHOR INFORMATION

Corresponding Author

*E-mail: [email protected]. Tel./Fax: 86-22-60601156. F

DOI: 10.1021/acs.jced.8b00715 J. Chem. Eng. Data XXXX, XXX, XXX−XXX

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ORCID

chloride, and borate Ions at 308.15 K. J. Chem. Eng. Data 2008, 53, 704−709. (19) Speight, J. M. Lange’s Handbook of Chemistry; McGraw-Hill: New York, 2005.

Yafei Guo: 0000-0003-0698-3565 Tianlong Deng: 0000-0002-1728-2943 Funding

The authors gratefully acknowledge partial financial support from the National Natural Science Foundation of China (U1607123 and 21773170) and the Yangtze Scholars and Innovative Research Team of the Chinese University (IRT_17R81). Notes

The authors declare no competing financial interest.

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REFERENCES

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DOI: 10.1021/acs.jced.8b00715 J. Chem. Eng. Data XXXX, XXX, XXX−XXX