Water-carbon dioxide mixtures at high temperatures and pressures as studied by infrared and Raman spectroscopies
نویسندگان
چکیده
The state of aggregation of water dissolved in supercritical carbon dioxide has been investigated under isobaric heating (T=40-340°C, P=250 bar) using infrared absorption and Raman scattering spectroscopies. Quantitative analysis of experimental spectra has shown that below 100°C, water exists only in its monomeric form (solitary water surrounded by CO2 molecules) whereas H-bonded species, namely dimers, begin to appear at higher temperature. At the same time, the ratio of dimers to monomers concentration increases with further temperature increase and at temperatures close to the temperature of total miscibility of the mixture (T=366°C, P=250 bar), only water dimers are present in the CO2-rich phase.
منابع مشابه
Fluids at high pressures and temperatures
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