ISSN 1017-2548(Print)
ISSN 2234-8530(Online)
Volume 47, Number 6
JKCSEZ 47(6)
December 20, 2003 

Polychlorinated biphenyls (PCBs) known as environmental contaminants in soil were analyzed by the soil pollution standard process test and the static supercritical CO₂ extraction mode. It was shown that the percent average recoveries of PCBs by the soil pollution standard process test were ranged in 25-35% and the corresponding standard deviations were above 10%. In contrast, the percent average recoveries of PCBs by the static supercritical CO₂ extraction mode were 2-2.5 times higher and standard deviations were within 7%. These results indicate that static supercritical CO₂ extraction mode may be a useful alternative to sample pretreatment certified by the soil pollution standard process test. The increasing supercritical CO₂ pressure from 1130 psi to 1996 psi at 40 oC enhanced the recovery of all PCB congeners from soil. However, at same T_c and P_c, the equilibrium time (5 versus 60 minutes) had no effect on the recovery of each PCB congener. Finally, similar PCB recoveries were obtained under the same extraction condition, regardless of the molecular weight and structure (coplanar versus non-coplanar) of PCB congeners.