Off-Line SFE of Bis(2-ethylhexyl) Phthalate from PVC Materials
Off-line supercritical fluid extraction with pure CO 2 was used to isolate and quantify bis(2-ethylhexyl) phthalate (DIOP) from PVC samples. Two modes of analyte trapping, onto an inner solid surface of a fused silica capillary (i.d. 0.5 mm) and direct bubbling through a bulk liquid (2-propanol), have been compared. Collected samples were analyzed by high performance liquid chromatography with UV detection. Quantitative recovery of over 95% was obtained in spite of limited operating parameters of home-made SFE device (maximum of pressure 30 MPa and of temperature 70 °C) for samples containing 10 or less wt.% of DIOP.