HPLC Determination of Nitrobenzenes in Water by Solid Phase Extraction

SPE-HPLC was applied to the determinations of nitrobenzenes in water,including nitrobenzene,2,4,6-trinitrotoluene,2,4-dinitrochlorobenzene,2-chloronitobenzene and 4-chloronitobenzene.The conditions of pretreatment of water sample solid phase extraction,and separation by liquid chromatography were tested and optimized.Nitrobenzenes in sample was enriched on the Porapak RDX column,and separated on C18 column(250 mm×4.6 mm,5 μm).A mixed solution of methanol and water(mixed in the ratio of 55 to 45) was used as mobile phase.UV-detection at 260 nm was adopted in the determination.Detection limit(2S/N) of the method was found in range of 0.8-1.8 μg·L-1.Tests for recovery and precision were performed,giving results of recovery in the range from 81.5% to 101.0% and value of RSD′s(n=7) in range from 1.1% to 5.6%.The proposed method has been used in determinations of nitrobenzenes in samples of surface water and drinking water.