High-pressure acoustic levitation devices allows a contact-free investigation of liquids. Here, acoustically levitated water droplets and pendant water droplets were examined in regards to the mass transfer coefficient in a static CO2-atmosphere under elevated pressures. Based on the droplet geometry and the decrease of the droplet volume over time, it was possible to calculate the mass transfer coefficient of water into CO2 at any given time. Additionally, open questions regarding possible differences between pendant and acoustically levitated water droplets were discussed.