Physical Solubility of N20 and C02 in Aqueous Solutions of Sodium Glycinate at High Pressure

As a new absorbent for carbon dioxide (C02), sodium glycinate was investigated
in this work. The physical solubility of nitrous oxide (N20) and C02 in pure water and
ofN,O in aqueous sodium glycinate solutions of various concentrations (1.0, 2.0 and 3.0
kmo1/m3
) had been measured experimentally at different pressures (20, 40 and 60 bar)
over the temperature ranging from 303.15 to 323.15 K. Since C02 reacts in the amine
group of sodium glycinate, the physical solubility of C02 cannot be measured directly
and thus N20 (a non-reacting gas) was used as a surrogate for C02. In order to estimate
the physical solubility of C02 in aqueous solutions of sodium glycinate, N20 analogy
had been applied. The physical solubility increases with a decrease in temperature and
with a decrease in concentration, as well as with an increase in pressure. In this work,
the optimum condition for physical solubility of C02 in aqueous solutions of sodium
glycinate at high pressure was achieved at low temperature of 30 'C and high pressure
of 60 bar.