IUPAC-NIST Solubilities Database

IUPAC-NIST Solubility Database
NIST Standard Reference Database 106

Solubility System: Carbon dioxide with Ammonium sulfate and Water

Components:
   (1) Ammonium sulfate; (NH4)2SO4; [7783-20-2]  NIST Chemistry WebBook for detail
   (2) Carbon dioxide; CO2; [124-38-9]  NIST Chemistry WebBook for detail
   (3) Water; H2O; [7732-18-5]  NIST Chemistry WebBook for detail

Original Measurements:
   Rumpf, B.; Maurer, G., Ber. Bunsenges. Phys. Chem. 1993, 97, 85-97.

Variables:
   Temperature = 313.13 K to 433.18 K
   Pressure = 313.13 K to 433.18 K
   Concentration = m₂/mol kg^-1 = near 2.00 and 4.00

Prepared By:
   H.L. Clever

Experimental Remarks:

   The authors used Pitzer's semiempirical model to correlate the data. The dissociation of the carbon dioxide can be neglected at the concentrations here. The system was treated as containing a non-dissociating gas, G and a completely dissociating electrolyte, MX. A temperature dependent interaction parameter, B°_{CO₂, (NH₄)₂SO₄}, and a temperature independent interaction parameter, Γ_{CO₂, (NH₄)₂SO₄, (NH₄)₂SO₄}, were derived from the experimental data.

For the CO₂ + (NH₄)₂SO₄ + H₂O system the values are:
B°_{CO₂, (NH₄)₂SO₄} = 0.7790 - 446.7(T/K)^-1 + 78900(T/K)^-2

which gives values:

T/K
313.15 353.15 393.15 433.15
B°_{CO₂, (NH₄)₂SO₄}
0.1571 0.1467 0.1533 0.1683

and Γ_{CO₂, (NH₄)₂SO₄, (NH₄)₂SO₄} = - 0.0083.

Experimental Data: (Subscripts 1,2,3, ..., in column headings refer to components 1,2,3, ...)

Solubility of carbon dioxide in aqueous ammonium sulfate
T/K	Pressure [MPa]	Molality m₁ [mol/kg]	Molality m₂ [mol/kg]
313.15	0.4060	0.0537	2.015
313.15	0.626	0.0808	2.015
313.14	1.594	0.1992	2.015
313.14	2.545	0.3075	2.015
313.15	3.607	0.4104	2.015
313.13	4.783	0.5130	2.015
313.13	6.370	0.6210	2.015
313.13	8.104	0.7073	2.015
313.16	8.968	0.7272	2.015
313.16	0.707	0.0646	3.989
313.14	1.138	0.1061	3.989
313.15	2.235	0.2005	3.989
313.14	3.619	0.3009	3.989
313.14	5.294	0.4021	3.989
313.13	7.716	0.5022	3.989
313.15	8.966	0.5453	3.989
333.13	0.0185	0.0	2.000
333.15	0.518	0.0494	2.015
333.16	1.086	0.0988	2.015
333.15	2.297	0.2008	2.015
333.13	3.618	0.3016	2.015
333.15	5.075	0.3984	2.015
333.14	6.876	0.4993	2.015
333.13	7.965	0.5511	2.015
333.14	9.346	0.5983	2.015
333.13	0.0181	0.0	3.934
333.15	0.796	0.0584	3.989
333.13	1.420	0.1006	3.989
333.15	3.114	0.2009	3.989
333.15	5.138	0.3013	3.989
333.16	7.789	0.4032	3.989
333.18	9.395	0.4482	3.989
353.10	0.0445	0.0	1.999
353.15	0.715	0.0495	2.015
353.19	1.437	0.1002	2.015
353.15	2.992	0.2008	2.015
353.15	4.720	0.3025	2.015
353.15	6.775	0.4023	2.015
353.15	7.991	0.4524	2.015
353.15	9.343	0.5012	2.015
353.15	0.0420	0.0	3.934
353.16	0.885	0.0517	3.989
353.14	1.848	0.1012	3.989
353.14	4.096	0.2013	3.989
353.15	5.428	0.2518	3.989
353.14	6.879	0.3022	3.989
353.14	8.540	0.3534	3.989
353.14	9.512	0.3785	3.989
393.16	0.1778	0.0	2.005
393.16	1.057	0.0506	2.005
393.16	1.770	0.0875	2.005
393.16	2.080	0.1005	2.015
393.18	2.768	0.1377	2.005
393.16	4.185	0.2007	2.015
393.16	4.950	0.2397	2.005
393.16	6.456	0.3010	2.005
393.16	7.483	0.3375	2.005
39315	7.739	0.3485	2.005
393.16	8.848	0.3907	2.005
393.16	0.1705	0.0	3.989
393.09	1.363	0.496	3.989
393.15	2.757	0.1009	3.989
393.14	4.198	0.1516	3.989
393.15	5.905	0.2030	3.989
393.15	7.743	0.2531	3.989
393.14	9.764	0.3042	3.989
413.11	0.337	0.0	1.982
413.15	1.291	0.499	2.005
413.15	1.808	0.0754	2.005
413.15	2.327	0.1006	2.005
413.16	4.526	0.2005	2.005
413.15	6.905	0.3013	2.005
413.16	6.975	0.3012	2.005
413.15	8.397	0.3519	2.005
413.15	9.868	0.4021	2.005
413.20	0.317	0.0	4.013
413.21	1.627	0.4889	4.013
413.11	3.214	0.1004	3.989
413.08	4.747	0.1499	3.989
413.14	6.621	0.2016	3.989
413.21	8.294	0.2413	4.013
413.08	8.580	0.2498	3.989
413.20	9.047	0.2592	4.013
433.15	0.572	0.0	2.005
433.14	1.594	0.0508	2.005
433.14	2.689	0.1006	2.005
433.12	3.827	0.1513	2.005
433.14	5.010	0.2012	2.005
433.10	6.297	0.2521	2.005
433.14	7.580	0.3014	2.005
433.12	9.011	0.3539	2.005
433.14	9.751	0.3782	2.005
433.15	0.546	0.0	4.013
433.15	1.986	0.0462	4.013
433.14	3.470	0.0921	4.013
433.16	5.036	0.1382	4.013
433.15	6.350	0.1751	4.013
433.16	7.361	0.2009	4.013
433.18	8.312	0.2256	4.013
433.10	9.372	0.2510	4.013

Method/Apparatus/Procedure:
   The apparatus is a modification of one used in earlier work (1). It consists of high pressure optical cell, thermostat, magnetic stirrer, thermocouples and Pt resistence thermometer, pressure transducers and tanks for aqueous solutions, rinse water and solute gas.
The thermostated about 30 mL high pressure optical cell is filled with carbon dioxide. Pressure and temperature of the gas are measured after equilibration. A known amount of aqueous solvent is added which is slightly greater than that needed to completely dissolve the gas. The pressure in the cell is reduced stepwise by removing very small amounts of the liquid until the first stable bubble apears.
The mass of carbon dioxide is calculated from the Bender equation (2). The volume of the cell is known within 0.06 mL. The solvent density is from the literature.

Source and Purity of Materials:
   (1) Carbon dioxide. Messer Griesheim, Ludwigshafen, > 99.995 mol %, used as received.
   (2) Ammonium sulfate. Merck GmbH, Darmstadt, > 99.5 mass %. Degassed and dried under vacuum.
   (3) Water. Deionized and degassed by vacuum distillation.

Estimated Errors:
   Solubility: δm₂/m₂ = ± 0.003
δm₁/m₁ = ± 0.1 to 0.03
   Temperature: δT/K = ± 0.1

References:
   1. Rumpf, B.; Maurer, G. , Fluid phase Equilib. 1992, 81, 241-60.
   2. Bender, E. 5th proc. Symp. Thermophys. Prop., ASME, NY, 1970, 227-35.