Na2SO4 + NaCl + H2O - American Chemical Society

Article pubs.acs.org/jced

Solid−Liquid Equilibrium for the Ternary Systems (Na2SO4 + NaH2PO4 + H2O) and (Na2SO4 + NaCl + H2O) at 313.15 K and Atmospheric Pressure Xiaorui Zhang, Yongsheng Ren,* Ping Li, Huijuan Ma, Wenjuan Ma, Chengqi Liu, Ya’nan Wang, Lingxin Kong, and Wei Shen Department of Chemistry and Chemical Engineering, Ningxia University, Yinchuan 750021, P. R. China ABSTRACT: Solid−liquid equilibrium in the ternary systems (Na2SO4 + NaH2PO4 + H2O) and (Na2SO4 + NaCl + H2O) at 313.15 K and atmospheric pressure was investigated by using isothermal solution saturation and moist residue method. The solubility and thermodynamic properties of the solution were determined. The phase diagrams and the diagrams of thermodynamic properties versus composition were constructed. It turned out that there was one invariant point, two uninvariant curves, and two crystallization regions. In the phase diagram of the ternary system (Na2SO4 + NaH2PO4 + H2O) at 313.15 K, the crystallization region of Na2SO4 was obviously larger than the NaH2PO4·2H2O crystalline region. When Na2SO4 was 11.57 wt % and NaH2PO4 was 44.41 wt %, this system reached saturation at 313.15 K. In the phase diagram of the ternary system (Na2SO4 + NaCl + H2O) at 313.15 K, the crystallization region of Na2SO4 was significantly larger than the crystallization region of NaCl. When NaCl was 22.56 wt % and Na2SO4 was 5.00 wt %, this system reached saturation at 313.15 K. The research results could be used for the optimization solvent extraction process of sodium dihydrogen phosphate in industrial production.

1. INTRODUCTION Sodium dihydrogen phosphate is an important raw material for the production of sodium hexametaphosphate, sodium pyrophosphate, and other varieties of phosphate salts. It has widespread application in the chemical industry, water treatment, agriculture aspects, and so on.1 In water treatment, it is mainly used for alkali corrosion control in boiler water treatment. In the metal surface treatment, it can be used for the surface treatment of steel parts before painting (derusting, degreasing). In the building materials industry, it can delay cement condensing. As a catalyst, sodium dihydrogen phosphate can be used to catalyze the synthesis of esters. In the chemical industry, it is also used as a pH buffer and bacteriological media when combined with other sodium phosphates. Moreover, the sodium dihydrogen phosphate is also used as fuel.2 Pure sodium dihydrogen phosphate can be used as a laxative, and it is also used in medicine for the treatment of hypophosphatemia. In the food industry, it can be used for food additives. In recent years, it has been developed rapidly and worldwide in the food and fermentation industries.3 High quality sodium dihydrogen phosphate is widely used in the microelectronics industry. With the rapid development of the electronics industry, it has a huge potential and wide market prospect. In the solvent extraction technology of industrial sodium dihydrogen phosphate,4,5 the product contains an amount of impurities when the industrial sodium chloride and the wetprocess phosphoric acid6 are mixed. However, the Cl− and SO42− in the system accumulates and crystallizes in the mother © XXXX American Chemical Society

liquid and cannot be removed even after a long series of impurity removing processes, which results in a lower quality of sodium dihydrogen phosphate. Therefore, to optimize the solvent extraction process of sodium dihydrogen phosphate and prepare a high quality of sodium dihydrogen phosphate, the solid−liquid equilibria of the ternary systems (Na2SO4 + NaH2PO4 + H2O) and (Na2SO4 + NaCl + H2O) are of vital importance in the crystallization process. Although the complete phase equilibrium data for the system (Na2SO4 + Na2HPO4 + H2O) at (298.15 and 313.15 K) has been reported in the literature,7 sodium dihydrogen phosphate (NaH2PO4, CAS: 7558-79-4) in our study and disodium hydrogen phosphate (Na2HPO4, CAS: 7558-80-7) in the references are not alike. However, the complete phase equilibrium data for the systems (Na2SO4 + NaH2PO4 + H2O) and (Na2SO4 + NaCl + H2O) at 313.15 K have not been reported in the literature yet, which is an impediment to the further exploration of the solvent extraction process of sodium dihydrogen phosphate. So it is necessary and urgently need to investigate solid−liquid equilibrium in the ternary systems (Na2SO4 + NaH2PO4 + H2O) and (Na2SO4 + NaCl + H2O) at 313.15 K and atmospheric pressure. Received: May 7, 2014 Accepted: November 21, 2014

A

dx.doi.org/10.1021/je500854m | J. Chem. Eng. Data XXXX, XXX, XXX−XXX

Journal of Chemical & Engineering Data

Article

2. EXPERIMENTAL SECTION 2.1. Materials and Apparatus. Doubly deionized water (electrical conductivity ≤ 1·10−4 S·m−1) was used in this experiment. The sources and purity of the materials are listed in Table 1.

beaker by a scoop, and the weight of the wet residues was measured. Afterward, the wet residue was dissolved by deionized water, and the solution was transferred to a 100 mL volumetric flask and diluted with deionized water. The small beaker was rinsed 5 to 7 times to ensure that all wet residues were transferred into the flask. Finally, these samples were quantitatively analyzed. 2.3. Analysis. The concentration of H2PO4− in the liquids and their corresponding wet residues of the solid phases were measured by the quinoline phosphomolybdate gravimetric method.16−18 The average relative deviation of the determination was less than ± 0.3 % by this method. The sulfate ion concentration was determined by means of barium sulfate turbidimetry.19 The chloride ion concentration was determined by means of the Volhard method.5,20 The average relative deviation of the determination was less than ± 0.5 % by this method. The density (ρ) was measured with a specific weighing bottle method with an uncertainty of ± 0.1 mg.21 The viscosity (η) was determined by an Ubbelohde capillary viscometer.5 All of the measurements of the mentioned thermodynamic properties of the equilibrium solutions were made in a constant temperature bath maintained at the desired temperature ± 0.05 K.

Table 1. Purities and Suppliers of the Materials Used chemical

mass fraction purity

NaH2PO4· 2H2O Na2SO4

≥ 0.99

NaCl

≥ 0.995

≥ 0.99

source Tianjin Kermel Chemical reagent Co. Ltd., China Tianjin Kermel Chemical reagent Co. Ltd., China Tianjin Kermel Chemical reagent Co. Ltd., China

A constant temperature bath oscillator (SHZ-C, Shanghai Langgan Laboratory Equipment Co. Ltd., China) with a temperature range from 293.15 K to 373.15 K was used for the phase equilibrium measurement. The temperature of this oscillator could be controlled to ± 0.05 K. 2.2. Experimental Methods. The solubility was determined by the method of isothermal solution saturation8−11 in this study. At a certain temperature, when pure Na2SO4 was added into the saturated solution of pure NaH2PO4, the solubility of NaH2PO4 decreased, because of the same ion effect. With further addition of Na2SO4, the NaH2PO4 solubility kept decreasing to a stop point. The solution is known as a cosaturation solution, in which either Na2SO4 or NaH2PO4 cannot be dissolved anymore. The composition of the solution at this temperature and pressure would not change, so this point is named as the invariant point in the phase diagram. Although Na2SO4 existed in the solution, only NaH2PO4 was saturated in the water before the solution reached cosaturation. In this way, we got a series of points that represented the solubility of NaH2PO4 in water. Similarly, by putting pure NaH2PO4 into a saturated solution of Na2SO4, points were attained representing the solubility of Na2SO4 in water. With the same method, the solubility of the ternary system (Na2SO4 + NaCl + H2O) can also be determined. It was quite difficult and cumbersome to separate the crystals from the mother liquor completely; therefore, the Schreinemaker’s method12−15 of wet residues was used to determine the composition of the solid phase indirectly. A known mass of sodium dihydrogen phosphate (sodium chloride), sodium sulfate, and doubly deionized water were loaded into a conical flask (250 mL). Then, the flask was sealed and placed into the constant temperature water bath oscillator. The oscillator vibrated continuously with temperature controlled at around 313.15 K, and the actual temperature of the complex was monitored by a mercury thermometer (uncertainty, ± 0.05 K). In this experiment, when the concentrations of the H2PO4− (Cl−) and SO42− in the solution both remain constant after 2 h, for caution’s sake, the oscillator was stopped after stirring another 1 h, and the temperature was kept at around 313.15 K for 1.5 h to allow any remaining solids to settle. After the system reached equilibrium, the saturated solution was removed into a 100 mL beaker at 313.15 K. The liquid phase, after weighting accurately, was added into a 100 mL volumetric flask and diluted with deionized water immediately. At the same time, some other liquid phases were used to measure density and viscosity individually according to the analytical method. The wet residues were removed into a small

3. RESULTS AND DISCUSSION A comparison between the experimental and literary results is shown in Table 2. It was found that experimental data were in good agreement with literary data, which confirmed that experimental methods are reliable in this study. Table 2. Solubility (S) in Pure Water (wt %) at T = 313.15 K and P = 101.32 kPaa this work salt

S/(wt %)

uncertainty u(w)b

NaH2PO4

58.79

ur(w1) = 0.01

Na2SO4 NaCl

33.23 26.26

ur(w2) = 0.02 ur(w3) = 0.05

literature S/(wt %) 58.1,22 58.023,24 32.8,25 32.4826 26.9327

uncertainty u(w) ur(w1) = 0.5 ur(w2) = 0.05

a

Standard uncertainties u are u(T) = 0.05 K, u(P) = 0.02 kPa. bw1, mass fraction of NaH2PO4; w2, mass fraction of Na2SO4; w3, mass fraction of NaCl.

3.1. Solid−Liquid Equilibrium for the Ternary Systems (Na2SO4 + NaH2PO4 + H2O). The phase equilibrium experimental data of solubility and the thermodynamic properties (η, ρ) measured for the ternary system (Na2SO4 + NaH2PO4 + H2O) at 313.15 K is shown in Table 3. The ternary system phase diagram is plotted in Figure 1 according to the experimental data of solubility. In Figure 1, the points M and N represent the equilibrium solubility of Na2SO4 and NaH2PO4 in water at 313.15 K corresponding to 33.23 wt % and 58.79 wt %, respectively; E is an invariant point at 313.15 K, which could indicate the cosaturated solution of NaH2PO4·2H2O and Na2SO4. Points W, A, B, and C represent H2O, pure solid of Na2SO4, pure solid of NaH2PO4·2H2O, and pure solid of NaH2PO4, respectively. ME and NE are saturation curves, which correspond to the solid phase of Na2SO4 and NaH2PO4·2H2O at 313.15 K, respectively; Connecting the points in ME and their corresponding points of wet residue and extending them shows that the intersection points of these extended tie-lines B



Article

Table 3. Solid−Liquid Equilibrium and Physico-Chemical Properties of the Ternary System (Na2SO4 +NaH2PO4 + H2O) at T = 313.15 K and P = 101.32 kPaa composition of liquid phase, 100 w no. 1,M 2 3 4 5 6 7 8,E 9,E 10 11 12 13,N

100 w1b 0.00 2.69 7.43 12.12 19.57 26.82 38.52 44.41 44.92 49.52 53.67 56.41 58.79

100 w2 33.23 31.00 22.30 20.01 18.69 13.23 12.44 11.57 10.67 7.09 4.94 2.61 0.00

composition of wet residue, 100 w 100 w1 d

ND 0.67 2.36 4.04 8.50 12.72 12.59 40.49 32.70 63.38 66.56 71.70 ND

thermodynamic properties of liquid phase

100 w2

ρ/(g·cm−3)

η/10−3Pa·S

equibrium solid phasec

ND 80.28 75.77 70.51 66.89 60.67 71.57 37.38 46.97 3.63 2.45 0.79 ND

1.3193 1.3371 1.3505 1.3654 1.3867 1.4215 1.4719 1.5455 1.5432 1.5444 1.5510 1.5515 1.5530

2.7348 3.0642 3.7637 4.4277 5.5253 6.1097 12.8660 16.0116 16.6726 18.1846 24.6453 26.1809 28.5933

S S S S S S S S+P S+P P P P P

a

Standard uncertainties u are u(T) = 0.05 K, u(P) = 0.02 kPa, ur(w1) = 0.01, ur(w2) = 0.02, ur(ρ) = 0.001, ur(η) = 0.05. bw1, mass fraction of NaH2PO4; w2, mass fraction of Na2SO4. cS, Na2SO4; P, NaH2PO4·2H2O. dND, not determined.

Figure 2. Phase diagram for the ternary system (Na2SO4 + NaH2PO4 + H2O) at (298.15 and 313.15) K: ○, literary data at 298.15 K;3 ●, experiment data in this study at 313.15 K; ···, 298.15 K; , 313.15 K.

2H2O, pure solid of NaH2PO4, and pure solid of Na2SO4· 10H2O, respectively; E1, F1, and F2 are the eutonic point of NaH2PO4·2H2O and Na2SO4 at 313.15 K, eutonic point of NaH2PO4·2H2O and Na2SO4 at 298.15 K, and eutonic point of Na2SO4·10H2O and Na2SO4 at 298.15 K, respectively. It was found that (1) increasing the temperature from 298.15 K to 313.15 K moves the invariant point upward from point E1 to F1. (2) Besides, the invariant point F2 disappears, because there is no Na2SO4·10H2O at 313.15 K. The curves suddenly turn. (3) The crystallization region of Na2SO4·10H2O transformed into Na2SO4·with the increase of temperature from (298.15 to 313.15) K. (4) The area of the crystallization region of NaH2PO4·2H2O was increased with the increase of temperature. (5) The crystallization region of Na2SO4 is larger than that of NaH2PO4·2H2O at both temperatures. From the data in Table 3, the relationship thermodynamic properties (η, ρ) of the saturated solution and the mass fraction of NaH2PO4 in the ternary system (Na2SO4 + NaH2PO4 + H2O) at 313.15 K were plotted in Figure 3 and Figure 4. Figure 3 shows the relationship between the density and the mass fraction of NaH2PO4 in the solution. It can be found that the solution density of this ternary system changes regularly with the mass fraction of NaH2PO4. The density tends to increase with the mass fraction of NaH2PO4 increasing in the saturated solution. The density increases significantly, at first,

Figure 1. Phase diagram for the ternary (Na2SO4 + NaH2PO4 + H2O) system at 313.15 K and 101.32 kPa: ○, equilibrium liquid phase composition; □, moist solid phase composition.

are approximately the solid-phase component for the compound Na2SO4. Similarly, linking the points in NE and their corresponding points of wet residue and extending them shows that the intersection points of these prolonged tie-lines are approximately the solid-phase component for NaH2PO4· 2H2O. The ternary phase diagram is divided into four regions by two solubility curves. The region of WMN (III) is the unsaturated region at 313.15 K, and NEB (II) is the crystallization region of NaH2PO4·2H2O, while MAE (I) represents the crystallization region of Na2SO4. AEB (IV) is the mixed crystallization region of NaH2PO4·2H2O + Na2SO4. It seems that the crystallization region of pure Na2SO4 (I) is larger than that of pure NaH2PO4·2H2O (II) at 313.15 K. When Na2SO4 is 11.57 wt % and NaH2PO4 is 44.41 wt %, the ternary system (Na2SO4 + NaH2PO4 + H2O) has reached saturation at 313.15 K. A comparison of the equilibrium phase diagrams for the ternary system (Na2SO4 + NaH2PO4 + H2O) at 298.15 K3 and 313.15 K is shown in Figure 2. Points W, A, B, C, and D represent H2O, pure solid of Na2SO4, pure solid of NaH2PO4· C



Article

and then increases slowly. When the concentration of NaH2PO4 is 44.41 wt %, scilicet the invariant point E, the density of the saturated solution is 1.5455 g·cm−3. The relationship between the viscosity and the mass fraction of NaH2PO4 in the solution is shown in Figure 4. It can be found that the solution viscosity of this ternary system changes regularly with the mass fraction of NaH2PO4. The viscosity increases continuously with the concentration of NaH2PO4 increasing in the saturated solution, rising from 2.7348·10−3 Pa· S to 28.5933·10−3 Pa·S. 3.2. Solid−Liquid Equilibrium for the Ternary Systems (Na2SO4 + NaCl + H2O). The experimental solubility, density, viscosity, and equilibrium solids of the ternary system (Na2SO4 + NaCl + H2O) at 313.15 K are listed in Table 4. According to these data, the phase diagram is given in Figure 5.

Figure 3. Density vs w (NaH2PO4) in the ternary (Na2SO4 + NaH2PO4 + H2O) system at 313.15 K and 101.32 kPa.

Figure 5. Phase diagram for the ternary (Na2SO4 + NaCl + H2O) system at 313.15 K and 101.32 kPa: ○, equilibrium liquid phase composition; □, moist solid phase composition.

As shown in Figure 5, the points P and Q represent the solubility of NaCl and Na2SO4 in water at 313.15 K, where the mass fractions of salts are 26.80 wt % and 33.23 wt %, respectively; E is an invariant point at 313.15 K, which could indicate the cosaturated solution of NaCl and Na2SO4. Points W, A, and L represent H2O, pure solid of NaCl, and pure solid

Figure 4. Viscosity vs w (NaH2PO4) in the ternary (Na2SO4 + NaH2PO4 + H2O) system at 313.15 K and 101.32 kPa.

Table 4. Solid−Liquid Equilibrium and Thermodynamic Properties of the Ternary System (Na2SO4 + NaCl + H2O) at T = 313.15 K and P = 101.32 kPaa composition of liquid phase, 100 w no. 1,P 2 3 4 5,H 6,H 7 8 9 10 11 12 13 14,Q

100 w1b 0.00 0.49 1.60 3.50 5.00 5.05 5.24 9.07 12.86 18.06 21.33 26.03 31.26 33.23

100 w2 26.80 24.73 23.34 22.94 22.56 22.58 23.02 17.93 10.94 6.86 3.49 2.28 1.34 0.00

composition of wet residue, 100 w 100 w1 d

ND 0.09 0.42 1.10 60.41 31.89 42.29 72.34 64.90 55.69 70.73 75.19 83.65 ND

thermodynamic properties of liquid phase

100 w2

ρ/(g·cm−3)

η/10−3Pa·S

equibrium solid phasec

ND 67.78 75.56 73.31 16.35 40.56 24.15 5.43 4.32 3.50 1.42 0.84 0.25 ND

1.1927 1.1978 1.2064 1.2154 1.2312 1.2293 1.2357 1.2380 1.2434 1.2721 1.2953 1.3149 1.3164 1.3193

1.3262 1.3578 1.4052 1.4747 1.6281 1.6189 1.6203 1.6863 1.7161 2.0281 2.2470 2.5446 2.5787 2.7348

Cl Cl Cl Cl Cl+S Cl+S S S S S S S S S

a

Standard uncertainties u are u(T) = 0.05 K, u(P) = 0.02 kPa, ur(w3) = 0.04, ur(w2) = 0.02, ur(ρ) = 0.001, ur(η) = 0.05. bw3, mass fraction of NaCl; w2, mass fraction of Na2SO4. cS, Na2SO4; Cl, NaCl. dND, not determined. D



Article

of Na2SO4, respectively. QH and PH are saturation curves, which correspond to the solid phase of Na2SO4 and NaCl at 313.15 K, respectively. The ternary phase diagram is divided into four regions by two solubility curves. The region of PHQ (III) is an unsaturated region at 313.15 K, and AHD (IV) is the mixed crystallization region of NaCl + Na2SO4, while APH (I) is the crystallization region of NaCl. ADHQ (II) is the crystallization region of Na2SO4. It can be seen from Figure 5 that the crystallization region of Na2SO4 (II) is larger than that of NaCl (I) at 313.15 K. When NaCl4 is 5.00 wt % and Na2SO is 22.58 wt %, the ternary system (Na2SO4 + NaCl + H2O) reaches saturation at 313.15 K. Figure 6 shows a comparison of the equilibrium phase diagrams for the ternary system (Na2SO4 + NaCl + H2O) at

Figure 7. Density vs w (NaH2PO4) in the ternary (Na2SO4 + NaCl + H2O) system at 313.15 K and 101.32 kPa.

According to Figure 8, it can be seen that the solution viscosity of this ternary system changes regularly with the mass

Figure 8. Viscosity vs w (NaH2PO4) in the ternary (Na2SO4 + NaCl + H2O) system at 313.15 K and 101.32 kPa.

Figure 6. Phase diagram for the ternary system (Na2SO4 + NaCl + H2O) at (298.15 and 313.15) K: ○, literary data at 298.15 K;26 ▲, literary data at 308.15 K;26 ●, experiment data in this study at 313.15 K; ···, 298.15 K; ---, 308.15 K; , 313.15 K.

fraction of Na2SO4. The viscosity increases with increasing Na2SO4 concentration. The viscosity increases slowly, at first, and then increases significantly. When the concentration of Na2SO4 is 5.00 wt %, scilicet the invariant point H, and the solution viscosity of this ternary system is 1.6281·10−3 Pa·S.

298.15 K,26 308.15 K,26 and 313.15 K. in which, W, A, L, and R represent water, pure solid of Na2SO4, pure solid of NaCl, and pure solid of Na2SO4·10H2O, respectively; H is an invariant point at 313.15 K, which could reflect the cosaturated solution of NaCl and Na2SO4; K1 is an invariant point at 298.15 K, which could reflect the cosaturated solution of NaCl and Na2SO4; K2 is aslo an invariant point at 298.15 K, which could reflect the cosaturated solution of Na2SO4·10H2O and Na2SO4. It was found that (1) increasing the temperature from 298.15 K to 313.15 K moves the invariant point upward from point H to K1. (2) Besides, the invariant point K2 disappears, because there is no Na2SO4·10H2O at 313.15 K. In addition, the curves suddenly turn. (3) The curve PH is close to the curve SK1, because the solubility of sodium chloride in water increases little when the temperature increases from 298.15 K to 313.15 K. (4) The crystallization region of Na2SO4·10H2O transformed into Na2SO4 with the increase of temperature from (298.15 to 313.15) K. (5) The area of the crystallization region of NaCl was increased with the increase of temperature. (6) The crystallization region of Na2SO4 is larger than that of NaCl at both temperatures. As shown in Figure 7, it can be found that the solution density of this ternary system changes regularly with the mass fraction of Na2SO4. The density curve of the equilibrium liquid phase in this system at 313.15 K tends to increase with the increasing Na2SO4 concentration. When the concentration of Na2SO4 is 5.00 wt %, scilicet the invariant point H, the solution density of this ternary system is 1.2312 g·cm−3.

4. CONCLUSION The solid−liquid equilibrium and the thermodynamic properties (density and viscosity) of the ternary systems (Na2SO4 + NaH2PO4 + H2O), (Na2SO4 + NaCl + H2O) at 313.15 K and atmospheric pressure were obtained. Additionally, the equilibrium phase diagrams for these systems were constructed. It turned out that there were in all one invariant point, two uninvariant curves, and two crystallization regions in the ternary phase diagrams. In the phase diagram of the ternary system (Na2SO4 + NaH2PO4 + H2O) at 313.15 K, the crystallization region of Na2SO4 was obviously larger than the NaH2PO4·2H2O crystallization region. When Na2SO4 was 11.57 wt % and NaH2PO4 was 44.41 wt %, the ternary system (Na2SO4 + NaH2PO4 + H2O) reached saturation at 313.15 K. In the phase diagram of the ternary system (Na2SO4 + NaCl + H2O) at 313.15 K, the crystallization region of Na2SO4 was significantly larger than the crystallization region of NaCl. When NaCl was 22.56 wt % and Na2SO4 was 5.00 wt %, the ternary system (Na2SO4 + NaCl + H2O) reached saturation at 313.15 K. The thermodynamic properties (η, ρ) of solution changed regularly with the increasing mass fraction of sodium dihydrogen phosphate (sodium sulfate). All results obtained in this experiment can be used for the solvent extraction process of sodium dihydrogen phosphate in industrial production and further theoretical studies. E



■

Article

(18) Liu, C. Q.; Ren, Y. S.; Wang, Y. N. Liquid−liquid equilibria for the quaternary system H3PO4−NaCl−H2O− TBP at 298.15 K. J. Chem. Eng. Data 2014, 59, 70−75. (19) Rankin, K.; Bejan, D.; Bunce, N. J. Electrochemical oxidation of the sulfide ion in synthetic geothermal brines in batch cells using coke electrodes. Ind. Eng. Chem. Res. 2010, 49, 6261−6266. (20) Zhu, T.; Li, C. M. Determination of the content of chloride ion in fertilizer material by Volhard method. Chem. Fert. Ind. 2002, 1, 23− 26. (21) Liu, C. Q.; Ren, Y. S.; Tian, D. Q.; Zhang, X. R.; Wang, Y. N.; Kong, L. X.; Shen, W. Equilibria of the quaternary system including phosphoric acid, hydrochloric acid, water and tri-n-butyl phosphate at T = 303.2 K and atmosphere pressure. J. Chem. Thermodyn. 2014, 79, 118−123. (22) William, F. L. Solubilities of Inorganic and Metal-Organic Compounds, 4th ed.; American Chemical Society: Washington, D.C., 1958; Vol. 2. (23) Eysseltová, J.; Makovička, J. Sodium dihydrogenphosphate. Alkali Metal Orthophosphates 1988, 31, 39−46. (24) Chen, J. F.; Tan, G. X. The Production and Application of Phosphate; Chengdu Science and Technology Press: Chengdu, China, 1989. (25) Lu, W. Z.; Liu, X. L.; Xiao, Z. J. Measurement and simulation of NaNO2 and Na2SO4 solubility in methanol and water. Shanghai Chem. Ind. 2007, 32, 18−21. (26) Deng, T. L.; Zhou, H.; Chen, X. The Phase Diagram of SaltWater System and its Application; Chemical Industry Press: Beijing, 2013. (27) Héctor, R. G.; María, E. T.; Teófilo, A. G. Compositions, densities, and refractive indices of potassium chloride + ethanol + water and sodium chloride + ethanol + water solutions at (298.15 and 313.15) K. J. Chem. Eng. Data 2003, 48, 405−410.

AUTHOR INFORMATION

Corresponding Author

*E-mail: [email protected]. Tel.: (0086 0951) 3951036. Fax: (0086 0951) 3951036. Address: Department of Chemistry and Chemical Engineering, Ningxia University. No.539, Helanshan West Road, Xixia District, Yinchuan, 750021, P. R. China. Funding

This research was financially supported by the “Western Light” Talent Cultivation Program of Chinese Academy of Sciences (CAS), 2012. Notes

The authors declare no competing financial interest.

■

REFERENCES

(1) Gong, C. S. Technology and Application of Advanced Phosphorus Chemical Engineering; Chemical Industry Press: Beijing, 2013; pp 593− 638. (2) Liu, M.; Tang, J. H.; Cui, C.; Li, C.; Chen, X. Z. Phase equilibrium in the aqueous ternary system NaH2PO4 + CO(NH2)2 + H2O at 298.15 K. J. Chem. Eng. Data 2013, 58, 132−135. (3) Chen, X. Z.; Tang, J. H.; Cui, Y. N.; Liu, M.; Mao, D. Phase equilibrium for the ternary system NaH2PO4 + Na2SO4 + H2O in aqueous solution at 298.15 K. J. Chem. Eng. Data 2014, 59, 481−484. (4) Duan, X. X.; Li, J.; Zhang, Y. Preparation of sodium dihydrogen phosphate by extraction method. Inorg. Chem. Ind. 2008, 40, 24−26. (5) Zhang, X. R.; Ren, Y. S.; Ma, W. J.; Ma, H. J. Solid + liquid phase equilibrium for the ternary system (NaCl + NaH2PO4+H2O) at T = (298.15 and 313.15) K and atmospheric pressure. J. Chem. Thermodyn. 2014, 77, 107−111. (6) Ye, C. W. Liquid−liquid equilibria for the ternary system containing water + phosphoric acid + organic entrainers at 308.15 and 328.15 K. J. Mol. Liq. 2013, 186, 39−43. (7) Eysseltová, J.; Makovička, J. Disodium hydrogenphosphate. Alkali Metal Orthophosphates 1988, 31, 97−126. (8) Trypuć, M.; Mazurek, K.; Białowicz, K. Solubility in the system NH4VO3+CO(NH2)2+H2O from 293 to 323 K. Fluid Phase Equilib. 2002, 203, 285−293. (9) Erge, H.; Adiguzel, V.; Alisoglu, V. Study of the solubility in Na− Ba−Cl−H2O, Na−Ba−H2PO2−H2O, Na−Cl− H2PO2−H2O, and Ba−Cl−H2PO2−H2O ternaries, and in Na+, Ba2+/Cl−, (H2PO2)−// H2O reciprocal quaternary system at 0 °C. Fluid Phase Equilib. 2013, 344, 13−18. (10) Blokhina, S. V.; Ol’khovich, M. V.; Sharapova, A. V.; Proshin, A. N.; Perlovich, G. L. Partition coefficients and thermodynamics of transfer of novel drug-like spiro-derivatives in model biological solutions. J. Chem. Thermodyn. 2013, 61, 11−17. (11) Niu, Z. D.; Cheng, F. Q. The Phase Diagram of Salt-Water System and its Application; Tianjin University Press: Tianjin, China, 2002. (12) Schott, H. Mathematical extrapolation for the method of wet residues. J. Chem. Eng. Data 1961, 6, 324−324. (13) Su, Y. G.; Lu, B. L.; Wang, X. R. Phase Diagram Analyses of Inorganic Chemical Production: Basic Theory; Chemical Industry Press: Beijing, 1985. (14) Schreinemakers, F. A. H. Graphical deductions from the solution isotherms of a double salt and its components. Z. Phys.Chem. 1893, 11, 109−765. (15) Nývlt, J. Solid-Liquid Phase Equilibria; Publishing House of the Czechoslovak: Czechoslovakia, 1977. (16) ESO/TC 47.ISO 3706−1976. Phosphoric Acid for Industrial Use (Including Foodstuffs)-Determination of Total Phosphorus (V) Oxide Content-Quinoline Phosphomolybdate Gravimetric Method; ISO Information Handing Services: Switzerland, 1976. (17) Wang, P.; Li, J.; Luo, J. H.; Jin, Y.; Yang, Z. P. Solid−liquid phase equilibrium for the ternary system K2SO4+ KH2PO4+H2O at (298.15 and 333.15) K. J. Chem. Eng. Data 2012, 57, 836−839. F


Na2SO4 + NaCl + H2O - American Chemical Society

Recommend Documents