Transcripción del resumen del autor: The JEFRI-PVT apparatus made in Canada by the Schlumberger company has been used to obtain accurate compressibilityfactormeasurements on high CO2-contentnaturalgasses so as to study the effect of different CO2content on gascompressibilityfactor (range covered: temperature, 263.15 K to 313.15 K; pressure, 3 MPa to 15 MPa; CO2content, 9.84, 28.86 and 50.99 mol%). The results showed that gascompressibilityfactors reduce with increasing CO2content in naturalgasses and increase with increasing temperature. In addition, a non-integral power polynomial correlation was proposed without an iterative procedure whose coefficients were determined by fitting experimental data. The mixing rules used include: Kay's mixing rule combined with Wichert-Aziz correlations (Kay) and Stewart-Burkhardt-Voo mixing rule with Wichert-Aziz (SBV). Comparison of the DAK-SBV, DAK-Kay, and proposed correlations showed that the presented model yielded the most accurate predictions with the lowest average absolute deviation (0.42%) among them.