Semiclathrate hydrates arewater-based host-guest compounds formed from aqueous solutions of ionic guest substances. These materials can greatly moderate formation pressures and temperatures from canonical gas hydrates. This is a significant advantage for industrial applications such as gas separation and storage. N2 gas is a major component contained in various flue gases and is usually mixed withCO2. Semiclathrate hydrates can separate these gases under moderate thermodynamic conditions. Tetra-n-butylammonium bromide (TBAB) is a widely used ionic guest substance. To develop the application technologies and their theoretical models, solubility data ofN2 gas in TBAB aqueous solutions are required. In this study, we report N2 gas solubility measured by an absolute gravimetric method for the semiclathrate hydrate formation system of TBAB + H2O+ N2. The measurement pressures, temperatures and TBAB mass fractions were 3MPa, 5 MPa and 7MPa, 292.15 K, 302.15 K and 307.15 K, and 0 (pure water), 0.10, 0.20, 0.32 and 0.40, respectively. The uncertainties were 0.056 MPa, 0.44 K and 0.00012 in mole fraction. Although the technical difficulty lays on measurements of small N2 gas solubility by the absolute gravimetric method, our data implied the unique gas dissolution property of aqueous TBAB solution depending on the TBAB concentration. The aqueous TBAB solutions with mass fractions of 0.10 and 0.20 had similarN2 gas solubility as that in purewater.With higher mass fractions, 0.32 and 0.40, the N2 gas solubility slightly increased from that in pure water, which implies the salting-in effect of TBAB.
Compounds
#
Formula
Name
1
C16H36BrN
tetrabutylammonium bromide
2
H2O
water
3
N2
nitrogen
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.