MATRIX INDEPENDENT SUPERCRITICAL-FLUID EXTRACTION OF POLYCYCLIC AROMATIC-HYDROCARBONS BY EMPLOYING BINARY MODIFIERS

A universal extraction method has been developed for polycyclic aromat ic hydrocarbons using supercritical fluids. The method is nearly matri x-independent and therefore applicable to different kinds of matrices with only minor changes. New binary modifiers, containing small amount s (1%) of active additives in organic solvents have been used. In cont rast to extractions with neat CO2 or CO2 modified with neat co-solvent s, the use of binary modifiers has resulted in significantly higher ex traction efficiencies for different kinds of matrices. The applicabili ty of the new modifier-solutions has been shown for three different ma trices, a fly ash, a sediment and a sewage sludge.