Affiliations: Research Institute of Innovative Technology for the
Earth (RITE), Tsukuba-division of RITE, East-Tsukuba, Tsukuba 305-8564, Japan.
e-mail: [email protected] | National Institute of Advanced Industrial Science and
Technology (AIST), East-Tsukuba, Tsukuba 305-8564, Japan
Abstract: The optical technology based on Mach-Zehnder interferometry was
successfully applied to a high-pressure liquid CO_2 and water system to measure
CO_2 solution density. Experiments were carried out at a pressure range of from
5.0 to 12.5 MPa, temperatures from 273.25 to 284.15 K, and CO_2 mass fraction
in solution up to 0.061. CO_2 solution density data were
obtained from two sets of experiments. These data were calculated through the
fringe shifts induced by density changes inside of the high-pressure vessel,
which were directly recorded during the experiments, and a modified version of
Lorentz-Lorenz formulation. The experimental results indicated that the density
ratio of CO_2 solution to that of pure water at the same
pressure and temperature is monotonically linear with the
CO_2 concentration in the solution. The slope of this linear
function, calculated by the experimental data fitting, is 0.275.