Determination of Benzene,Toluene and Xylene in Waste Liquor from Presswork

The waste liquor from presswork was pretreated using ethyl acetace as solvent and benzene,toluene and xylene in it was determined by GC.The recoveries of standard addition are 95.72%—102.66%,the relative standard deviation(n=6)are smaller than 3.29%,the detection limit of benzene is 0.50mg/L.The method is efficient,accurate and easy to operate.