A continuously stirred high pressure solubility vessel has been directly interfaced online to a supercritical fluid chromatography (SFC) system using a single valve recirculation interface. The recirculation pump built into the interface maintains a constant flow of fresh supercritical fluid carbon dioxide solution from the solubility vessel through the interface sample injection valve in a return flow circuit. A series of progressively more concentrated anthracene and chrysene solutions were separately prepared by incrementing the pressure within the solubility vessel in controlled steps. Prior to performing online SFC solubility measurements for each polyaromatic hydrocarbon, in situ checks were made to establish that fully saturated solutions were formed at each different pressure step. The method also involves the utilization of a self-validation experimental procedure to check the accuracy of solubility measurements. For anthracene, solubility data was obtained at 313, 323, 333, and 343 K through the pressure range 10-28 MPa using 2 MPa steps. For chrysene, solubility data was obtained at 313, 323, 333, and 343 K through the pressure range 10-27.5 MPa using 2.5 MPa steps. All sets of experimental solubility data were correlated according to the density based models of Mendez-Santiago Teja and Bartle.