ABSTRACT
An analytical procedure for the determination of water-and methanol-extractable pentachlorophenol ( PCP) in soils using vortex assisted liquid-liquid extraction ( VALLE ) and gas chromatography ( GC ) was developed. Significant extraction parameters, such as liquid-liquid ratio and vortex speed were optimized. The recovery of PCP was the highest ( 97. 4%) at the vortex rotation speed of 2000 r/min, with good reproducbility and a small relative sdandard deviation ( RSD, 0. 5%), with regard to the volume ratio of derivatization solution to n-hexane, the recovery of PCP was 103% with an RSD of 0. 7% at 10:4. The linearity of the calibration ranged from 1. 25 μg/L to 4000 μg/L, with a correlation coefficient ( R2 ) of 0. 9999. The detection limit of the PCP in water was below 0. 2 μg/L. Compared with traditional liquid-liquid extraction ( LLE) and solid phase extraction ( SPE) , the VALLE method was more simple and more economic in terms of chemical consumption, also with a recovery of 96. 8% and a RSD of 3. 7%. Four different soils were used to check the reliability of this method. The soils were respectively extracted with water once and methanol three times. The total recoveries were 89. 5%-98. 9% and 88. 7%-98. 4% at the PCP spiking level of 1 and 10 mg/kg, respectively. It is concluded that the VALLE method satisfied the extraction and determination of water and methanol extractable PCP in soils with varying PCP polluting rates.