Solubility of sulfur dioxide

The solubility of sulfur dioxide in melts may be ascribed to two concomitant processes ... 

Sulfur dioxide dissolves in water, forming a weak acid solution of sulfiirous acid, H2S03 however, the pure substance H2S03 has never been isolated. At 101.3 kPa (1 atm) sulfur dioxide pressure, the solubility of sulfur dioxide is 18.5% at 0°C and 5.1% at 40°C. Lower solubilities are observed when other diluent gases, eg, air, are present. At 25°C, the hypothetical H2S03 has a first ionization constant of 1.72 x 10-2 and a second ionization constant of 1.1 x 10-9. Atlow temperatures, concentrated sulfurous acid affords a crystalline hydrate, S02 6H20 [24402-69-5]. 

The index of refraction of sulfuric acid solutions (62) and additional related data (66), along with solubility data for oxygen in sulfuric acid solutions (67), are available in the literature. The solubility of sulfur dioxide in concentrated sulfuric acid is shown in Figure 9 (68) additional data are also available (69). 

The density of oleum at 20°C (76) and at 25°C (39) has been reported. The boiling points of oleum are presented in Figure 15 (86). Freezing points are shown in Figure 16 (75,87). An excellent discussion on the crystallization points of oleum is available (69). The solubility of sulfur dioxide in oleum has been reported (68,69). Viscosity of oleum is summarized in Figure 17 (55) additional viscosity data are available (76). 

Environmental Protection. During the reduction of barite and the calcination of Sachtolith and lithopone, sulfur dioxide is liberated. This is removed from the waste gas in a purification stage which is based on the reversible, temperature-dependent solubility of sulfur dioxide in poly glycol. The absorbed sulfur dioxide can be recovered as a liquid product or as a raw material for sulfuric acid. Any soluble barium in the residue from the dissolution of the fused BaS is removed by treatment with... 

Although the temperature of the liquid film changes by 10 K due to an increased inlet temperature from 100 °C to approx. 190 °C, the effect of increased solubility of sulfur dioxide (Fig. 16.22) or calcium hydroxide on the conversion plays an insignificant role. 

A parameter of significant importance in cell performance is the operating temperature. Figure 4 shows the measured effect of temperature on the electrode potential for the WAE-3 electrode of Figure 3. As can be seen, a distinct decrease in anode overpotential occurs as temperature is increased from 25 to 90 C. It should be noted that the pressure of the cell was kept constant, at atmosphere pressure, over the range of temperatures. This constant pressure, while temperature is increasing, results in a substantial drop (from 1M to 0.16M) in the solubility of sulfur dioxide in the electrolyte. The decreased sulfur dioxide content precludes... 

The solubility of sulfur dioxide is greater in oleum and increases rapidly... 

The solubility of sulfur dioxide in aqueous solutions, S, can be expressed as a function of the partial pressure in the gas phase (p), Henry s Law constant (H), the hydrogen ion concentration (H+), and the ionization constants of sulfurous acid (Ki and K2) ... 

In more efficiently designed and operated sulfur burners such as those used in the paper industry and in the manufacture of sulfuric acid (Shreve, 1944), the sulfur is melted, atomized in compressed air, and burnt in a separate combustion chamber. In these burners gas of a constant composition, 19-20 volume per cent SOa, without any sublimation and with only 0.14% of the sulfur transformed into SOs, can be obtained. Sulfur dioxide is a colorless gas having a characteristic odor, a normal molecular volume of 21.89 1., and a molecular weight of 64.06 g. It is soluble to the extent of 36.4 volumes in one volume of water at 20° C. Its solubility in water decreases from 8.6% by weight at 20° C. to 0.1% at 100° C. At atmospheric pressure SO2 liquefies at —10° C. at 20° C. liquid SO2 exerts a pressure of 3.25 atm. or 40.6 p.s.i. The solubility of sulfur dioxide in water has been determined accurately by Beuschlein and... 

Bertin, C. 1924. Auto-desulfiting of musts. Bull. soc. ind. Rouen 62, 427-434. Beuschlein, W. L., and Simenson, L. 0. 1940. Solubility of sulfur dioxide in water. 

D5. Johnstone, H.F. P.W. Leppla, "The solubility of sulfuric dioxide at low partial pressures. The ionization constant and heat of ionization of sulfurous acid , JACS, vS6, pp2233-2238 (1934)... 

The solubility of sulfur dioxide in pure water in equilibrium with pure gases is given in Figure 7-6, which is based on the data of Parkison (1956). As indicated by the equations, the amount of sulfur dioxide absorbed by an aqueous system can be increased by reducing the... 

Figure 7-6. Solubility of sulfur dioxide in pure water. Data ofParkison (1956)...

Figure 7-27. Solubility of sulfur dioxide In anhydrous dimethylaniline and various xylldine-water mixtures. DataofPastaikovmdAstaslma(1M9andFlemliw Fitt(1950)...

The effects of temperature and xylidine/water ratio on the solubility of sulfur dioxide in xylidine-water mixtures are shown in Figure 7-28. This figure is based upon pure sulfin dioxide gas. According to Roesner (1937), the heat of reaction for the absorption of sulfur dioxide in xylidine is 4.7 kilocal/g mole (132 Btufib) sulfur dioxide absorbed. 

Fig. 75. Solubility of sulfur dioxide in halobenzenes at 1 atm and various temperatures fC. (1) C6H5l (2) QHsBr (3) QHsQ. Line 4 (R) is a plot of the mole ratio jCso2 values obtained from the R-lines at different temperatures.

Fig. 76. Solubility of sulfur dioxide in chlorobenzene at different temperatures t°C and pressures pso2-Line 1 is the mole fraction Nsoz vs Psoz 25°C from the data of Horiuti line 2 is the corresponding...

Fig. 77. Solubility of sulfur dioxide in hydrocarbons at 1 atm and different temperatures t°C. Mole ratio jCso2 vs t°C plots for (1) QH6 (from data by Horiuti ) (2) dicumylmethane, C19H24 (4)...

Fig. 78. Solubility of sulfur dioxide is alcohols at 1 atm and different temperatures r°C. The mole ratio JCS02 vs t°Care for(l) n-CgHiyOH, (2) HOCH2CH2OH, and (3) CH3OH. Line 4 (R) is the JCso2 P ot based on the R-lines.

Fig. 81. Solubility of sulfur dioxide in the alkylanilines at 25 C. Plots of the mole fraction N 02 pressure Pso2 od mole ratio Xso2 vs Pso2 on the R-line diagram. The liquids are (1,N 5,X) QH5N(C2H5)2 (2,N 6,X) C6H5NHC2H5 (3,N 7,X) C6H5NHCH3 (4,N S,X) QH5N(CH3)2. The pressures pso2 are in mm Hg.

Fig. 82. Solubility of sulfur dioxide at 0°C. Line 1 is the mole fraction Nso2 pressure pso2 plot for ethylene glycol based on published data the cross bar is the maximum pso2 observed. Line 2 is a similar plot for diethylaniline. The crosses on lines 1 and 2 are the values obtained by the present writer line 3 is for dimethylaniline from data likewise obtained by the bubbler procedure. Lines for methylaniline and ethylaniline lie between lines 2 and 3. The pressures pso2 ire in mm Hg.

Fig. 84. Solubility of sulfur dioxide in water at 0°C. Plot of the mole ratio xso vs total pressure...

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