To develop the separation process using supercritical (sc) CO2 regeneration of waste lubricating oil, the equilibrium solubilities of iso-eicosane in the binary iso-eicosane-supercritical CO2 system were obtained at 313.2 K, 328.2 K 343.2 K, and 358.2 K under pressures ranging from 7.24 MPa to 14.68 MPa. The solubilities of this component increased with a pressure increase, whereas they decreased with temperature increase. The Chrastil equation and Adachi and Lu equation were used correlate the solubility behavior of iso-eicosane in supercritical CO2, which revealed that both equations are in good agreement with the experimental data. Since the AARD values of the Chrastil equation range froth 0.42 % to 4.99 % and the AARD values of Adachi and Lu equation range from 0.16 % to 1.70 %, it was shown that the Adachi and Lu models better agreement with the experimental data.