Measurement of the mass transfer into single drops in the system of water/supercritical carbon dioxide

This paper presents a new method for the measurement of mass transfer in is olated water drops. The transport of a component in the water drop can be d etected by a change in electrical conductivity. Measurements were performed using a new type of sensor design. In particular the transfer of CO2 from a continuous fluid phase into the water drop was investigated. CO2 leads to an increased conductivity in water because of the carbonic acid equilibriu m. Experimental conditions ranged from 298 to 323 K in temperature and from 2.5 up to 30.7 MPa in pressure. The mass transfer coefficients obtained gi ve insight into the transfer process and its physical mechanisms. Increasin g temperature and density of the surrounding carbon dioxide lead to faster mass transfer processes. The effects of drop geometry and internal turbulen ces on the mass transfer velocity are discussed. (C) 2000 Academic Press.