| There is 30 million kilogram nitrobenzene system pouring into the environment, and the needof nitrobenzene was added 3.1％every year. with the development of moden industry of chemical.There will be more nitrobenzene to pure into the environment in many ways. The polluted riverwill break the ecosystem when it pass throgh the region, when nitrobenzene in the water ofirrigation it will be flowed into the farmland, and pollute the soil of farmland, damage themicroorganism in soil, break the structure of the soil, cause the soil environment worsening.nitrobenzene enriched by the plant will seriously influance human's health. The similar thingsoccurred in the place of producing nitrobenzene and aniline in the world.This paper deal with the problems about water pollution of nitrobenzene in the Song hua Riverin 2005. Tht rivers flow after the region of cropland is polluted heavily by nitrobenzene. Themethod of determining nitrobenzene in the water is common, but the method of detection in soil islacked and complicated, It is difficult to fit the need of moden analyzing residue. Estabilished amethod of nitrobenzene in soil extraction and detection and research nitrobenzene in soil analysison the residue dynamics. The aim of this thesis is to provide theory gist and technical directors inproper use of production of crops and manage the soil pollution.This study included four aspects: (1)The detection condition of nitrobenzene in GC-MS; (2)The solid-phase extraction condition of nitrobenzene cleaned by C18 SPE cartridge; (3)Extractingmethod of nitrobenzene in soil; (4) Preliminary research on the residue dynamics of nitrobenzenein soil. The research details and results mainly included the following aspects:1. The gas chromatography conditions of nitrobenzene detection in soil assured by study were:carrier gas: pure helium(99.999％); column pressure: 48.1KPa; column flux: 1.80ml·min-1; oventemperature: 120℃; injector tempreture: 250℃; injection mode: split sampling; split ratio: 10:1;volume of the sample was set at 1.0μl with the shunting ratio of 10:1; injecting volumes: 1.0μl.2. The Mass Spectrometry conditions of nitrobenzene detection in soil assured by study were:temperature of ionic source: 200℃; interface temperature: 250℃; ionization mode: EI; inoizationenergy: 70eV; gather mode: SIM; External mark peak acreage method was fix quantify. Solventremoval time: 3.0min; Tune mode: automatic tune.3. The optimum conditions of the method for extracting of nitrobenzene in soil was as thefollows: nitrobenzene were extracted by the solution of acetone/hexane (1:1, by volume) 20.0ml, extracting-temperature 30℃, extracting-time 15.0 minutes and repeated-times 3.4. The optimum conditions of solid phase (clean up the sample) were: The best operationconditions were studied for the determination of nitrobenzene by solid phase.5. The rate of recovery of the method that nitrobenzene in soil extraction and detection is83.0％～93.9％, precision is 1.80％～4.04％. Detection limit is 0.0016mg·kg-1.6. The water content of soil strongly affect nitrobenzene in soil residue. The results showedwhen the water content of soil is 14％, the half life of nitrobenzene is about 4.9 days; when thewater content of soil is 17％, the half life is about 3.8 days; and when the water content of soil is20％, the half life is about 1.9 days.7. The temperature of soil is strongly affect nitrobenzene in soil residue too. The resultsshowed when the temperature of soil is 4℃, the half life of the nitrobenzene is about 6.5 days; andwhen the temperature is 15℃, the halfe life is 4.4 days; and when the tempature is 25℃, the halflife is 3.2 days.8. The pH of soil is strongly affect nitrobenzene in soil residue too. The results showed whenthe pH of soil is 4.5, the half life of the nitrobenzene is about 7.2 days; and when the pH is 7.0, thehalle life is 5.4 days; and when the pH is 9.5, the half life is 3.6 days.
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