A new isochoric apparatus was built for PVTx measurements in an extended temperature range from (210 to 360) K and at pressures up to 6.0 MPa. The setup was used to measure PVTx properties for the R116 + CO2 and R41 + CO2 systems, both in the two-phase and superheated vapor regions. The binary interaction parameters were derived from experimental data in the two-phase region by applying the flash method and the Carnahan-Starling-DeSantis equation of state (CSD EOS). The dew-point parameters were found by interpolating the P-T isochoric sequences, again applying the CSD EOS. A composition-dependent mixing rule implemented in the CSD EOS improved the VLE data representation of both binary systems. The resulting binary interaction parameters were used for VLE parameter derivation. The superheated vapor region data were compared with those obtained by the Burnett method and using REFPROP 7.