Thermodynamics Research Center / ThermoML | Journal of Chemical and Engineering Data

ABSTRACT

The solubilities of ammonia (NH3) in glycerin (G) as well as its derivatives were measured at 303.15 K, 313.15 K, 323.15 K and 333.15 K under pressures up to 570.0 kPa using isochoric saturation method. Three glycerin derivatives include glycerol formal (GF), DL-1,2-isopropyli-deneglycerol (GAK), and 3-methoxy-1,2-propanediol (MP). Henry's constants and thermodynamic properties such as dissolution Gibbs free energy, enthalpy, and entropy changes of NH3 solvation were derived by fitting the experimental data. The results showed that the gravimetric solubilities of NH3 in these solvents changes along with the sequence of G greater than GF greater than MP greater than GAK. The solubility of NH3 in the solvents increased with the increasing pressure or the decreasing temperature. All the dissolving enthalpies were negative at each condition. The dissolution of NH3 was a spontaneous process. By comparative comparison of dissolving ability, properties, price and environmental impact between present solvents and other absorbents in the literatures, glycerin was believed as a potential NH3 captures in the industry.