Abstract：Abstract: The sludge samples were dried by vacuum freezer dryer and firstly extracted with n-hexane/
dichloromethane ， and then the impurities in the samples were separated with neutral alumina column ，
and finally the nitrobenzene compounds was detected with GC-MS. The newly established analysis
method not only optimized the process of sample extraction and conditions for solid phase extraction ，
but also homogenized the samples with vacuum freezer dryer and greatly reduced the pretreatment time
by the extraction with ultrasonic apparatus and vortex mixer. The Method Detection Limits （ MDLs ）
were from 0.06 to 0.73 mg · kg -1 ， and the recovery rate of standard solutions was in the range of 75%
and 120%.
2019, Vol. 36 
