Isothermal pressure (p)-mass fraction (w) phase diagrams were measured for CO2 + tetradecanoic acid at six temperatures from 328.2 K to 373.2 K and for CO2 + docosane at four temperatures from 343.2 K to 393.2 K as well as isobaric temperature (T)-mass fraction (w) phase diagrams for both systems at 34.5 MPa. In addition the isothermal and isobaric Gibbs phase prisms at 373.2 K and 34.5 MPa respectively were determined for the ternary system CO2 + tetradecanoic acid + docosane, and an isobaric miscibility window was found between 333 K and 385 K at 34.5 MPa.