SDS Volume
Volume 62. Carbon Dioxide in Water and Aqueous Electrolyte Solutions, p None
Source Publication
Cramer, S. D.; Rep. Invest. - U. S.; Bur, Mines 1982, RI 8706.
Conditions:
Room Temp:
278.05 - 522.35
$\pu{K}$
Pressure:
0.8 - 5.9
$\pu{MPa}$
Amount concentration (2):
C2/mol dm-3 = 0 and 4.19
g/L
Compiler:
Methodology:
The solubility of $\ce{CO2}$ was determined from pressure-volume-temperature (PVT) measurements using the technique of gas extraction. The apparatus consisted of (1) a high-pressure, high-temperature section for dissolving the gas in the brine, (2) a heat exchanger or cooling (or heating) samples of gas-saturated brine to room temperature, and (3) a low-pressure, constant temperature section for making PVT measurements on collected gas and liquid samples.
A two liter, type 316 stainless steel stirred reactor, fitted with a heat and chemical-resistant glass liner, was filled two-thirds full with brine. The brine was deaerated by evacuating the reactor to the vapor pressure of the brine for at least 3 minutes. Upon reaching thermal equilibrium, the gas was injected into the reactor and allowed to distribute at a fixed partial pressure between the vapor and liquid phases. Equilibration occurred within 5 hours at 150 °C and above, and within 24 hours at lower temperatures. The concentration of $\ce{CO2}$ in the liquid was determined by desorption from a known volume of liquid followed by volumetric analysis of the evolved gas.
Sample Information:
- 99.5%.
- Prepared from reagent grade chemicals.
- Demineralized.
Measurement Errors:
Ambient temperature: δKH/KH = 0.058 (by author)
(Detailed analysis of experimental contributions to the total error is given in the source.)
System Components:
- Carbon dioxide, $\ce{ CO2 }$; [124-38-9] NIST WebBook
- Seawater, $\ce{ H2O }$; [7732-18-5(C)] NIST WebBook
- Water, $\ce{ H2O }$; [7732-18-5] NIST WebBook
Experimental Data
Salton Sea geothermal brine (SSGB) was a synthetic brine based on Helgeson's analysis of unflashed hypersaline brine from geothermal well IID-2 which is located in the Imperial Valley of California (Helgeson, H. C., Am. J. Sci. 1968, 266, 129-166).
Detailed composition for the SSGB is given in Table 1.
The pH (measured at 25°C) of SSGB is 4.6. For experimental purposes the pH of the brine was adjusted to neutral by the addition of NaOH.
The synthetic SSGB was prepared from chloride salts of the constituent metal ions, sodium silicate, sodium sulfide, and sodium metaborate, in sccordance with the composition given in Table 1.
| $C_{1}$ (ppm) |
|---|
| 2.5E+2 |
| 3.9E+2 |
| 2.88 x 104 |
| 2E+1 |
| 1.55 x 105 |
| 3a |
| 2 x 103 |
| 8E+1 |
| 2.1E+2 |
| 1E+1 |
| 1.37 x 103 |
| 1.65 x 104 |
| 7E+1 |
| 4E+2 |
| <1 |
| 5.3 x 104 |
| 4.4E+2 |
| 3E+1 |
| 5E+2 |
(a) Not included in synthetic brine.
(a) Calculated by the compiler.
(b) KH = P1Ø1/x1, where KH = Henry's law constant, P1 = partial pressure of gas (P1 = P - P2; P2 is the vapor pressure of water at the corresponding temperature), Ø1 = fugacity coefficient (Smith, J.M. and Van Ness, H.C. Chemical Engineering Thermodynamics, McGraw-Hill, New York 1959), and x1 = mole fraction of the dissolved CO2.
