Thermodynamics Research Center / ThermoML | Fluid Phase Equilibria

Vapor-liquid equilibria of NH3 in (NH3 + H2O) and (NH3 + PZ + H2O) system

Liu, J.[Jinzhao], Wang, S.[Shujuan], Hartono, A.[Ardi], Svendsen, H. F.[Hallvard F.], Kim, I.[Inna], Chen, C.[Changhe]
Fluid Phase Equilib. 2011, 311, 30-35
ABSTRACT
Volatility is an important issue for aqueous ammonia used as an absorbent for post-combustion CO2 capture. Vapor-liquid equilibrium (VLE) of NH3 in aqueous ammonia and aqueous blends of ammonia and piperazine (PZ) were measured at 20 C, 30 C and 40 C. The experimental VLE results for NH3 cover the mole fraction ranges 2.5 to 15 % NH3 (aq) in aqueous ammonia and 2.5 to 15 % NH3 in the 0.4 M PZ blended solutions. Vapor pressures of NH3 for 5%, 10% and 15% NH3 (aq) were compared with available data in the literature. Activity coefficients for NH3 in NH3 (aq) and aqueous blends of NH3 + PZ were calculated and compared for different temperatures to obtain the effect of PZ on the volatility of aqueous ammonia. The eNRTL model was used to model the results and a comparison between model predictions and experimental data shows good agreement.
Compounds
# Formula Name
1 C4H10N2 piperazine
2 H3N ammonia
3 H2O water
Datasets
The table above is generated from the ThermoML associated json file (link above). POMD and RXND refer to PureOrMixture and Reaction Datasets. The compound numbers are included in properties, variables, and phases, if specificied; the numbers refer to the table of compounds on the left.
Type Compound-# Property Variable Constraint Phase Method #Points
  • POMD
  • 1
  • 2
  • 3
  • Partial pressure, kPa - 2 ; Gas
  • Temperature, K; Liquid
  • Mole fraction - 2; Liquid
  • Mole fraction - 1; Liquid
  • Gas
  • Liquid
  • infrared spectroscopy of acid wash
  • 24