Solubility of used frying oil in three compressed gases (propane, carbon dioxide, and ethane) has been determined using a dynamic flow method. The aim of the work has been to analyze and compare the solubilities in such gases in order to determine the best processing conditions leading to selective separation of nondegradated triglycerides from polar components. A second objective has been to obtain empirical correlations to predict these solubility data for further scale-up applications. The effect of pressure and temperature on the solubility has shown that the variable increases as solvent density and/or solute vapor pressure increase. Best results have been attained using ethane at 29.4 MPa and 25 degrees C. At such conditions the solubility of the oil was high (17 g/(kg of ethane)), being triglycerides its major constituents (83.2% by weight), and only 0.4 and 16.4%, respectively, the weight percentages of HMWC and LMWC. HMWC and LMWC refer to polar compounds with molecular weight higher and lower than that of triglycerides. Finally, it has been found that the Chrastil's model can successfully estimate the solubilities of used frying oil lipids in nonpolar solvents such us propane, carbon dioxide, and ethane.