| Snow and ice are important components of cold ecosystems as well as of temperate ecosystems in winter. In recent years, with the rapid development of chemical industry, a large number of organic pollutants enter the atmosphere, rivers, lakes, ice and snow. The date demonstrated that persistent, bioaccumulate and toxic substances (PBTs) had already discovered in the Arctic. Because of special characters of ice and snow, relative to mobility of atmosphere and water body, pollutant physical moving course in the inner of ice and sow, routine chemical reaction and microorganism effect relatively weak, but photochemistry influenced less by temperature shows special importance. So, the photochemistry of the organic pollution has very important significance in ice and snow.Now people still little study on photoconversion of organic pollutants in ice and snow. Aspects of this research are still new area. Abroad has just begun, there has no reports in domestic. In this article, we adopted representative phenols—phenol, under the condition of the laboratory simulation, influence factors, photoconversion kinetics and intermediates were investigated under the high pressure mercury lamp and simulated solar, the photolysis mechanism of phenol in ice is laid out under this experimental condition. It has great significance in deeply understanding photoconversion mechanism of phenol in ice, and photoconversion difference of phenol in aqueous solution and ice; it can be used to presume that effect of environment in cold ecosystems caused by the change of phenol. Under the condition of atmospheric ozone layer depletion and enhanced UV radiation at present, the results of paper are more practical significance. It could be supplied a scientific theoretical basis for predicting the phenolic pollutants potential of ecological environment risk.The effects of reagent concentration, light intensity and pH value etc. have great influence on photoconversion of phenol under the high pressure mercury lamp. Under UV irradiation, the phenol has direct photolysis and indirect photolysis with the presence of H2O2, NO3- and NO2-. The concentration of phenol has no change under dark condition. The results show that the photoconversion rate of phenol increases rapidly with the increasing of the initial concentration of H2O2, NO3-, NO2-and light intensity, and decreases with the increasing of the initial concentration of phenol. The photoconversion course follows the first-order kinetics equation. Under the high pressure mercury lamp, when the direct photolysis of phenol,The addition of Fe3+ or Fe2+, the photoconverison rate of phenol is decreased. The addition of NO2-,NO3- or HCO3-,respectively, the photoconverison rate of phenol is increased. There was no obvious effect of addition of Cl-. With the presence of H2O2, the addition of Fe3+ or Fe2+, the photoconverison rate of phenol is decreased. There was no obvious effect of addition of Cl- or HCO3-. With the presence of NO3- and NO2- separately, there was no obvious effect of addition of Fe3+, Fe2+, Cl- or HCO3-, respectively. For phenol and phenol with the presence of H2O2, the stronger acid conditions facilitate the photoconversion of phenol, the stronger alkali conditions inhibit the photoconversion of phenol. For phenol with the presence of NO3- and phenol with the presence of NO2-, under the strong acid or alkali decreases the photoconversion rate of phenol. Using different type of water, the photoconversion rate of river water sample was faster than distilled water.Under the high pressure mercury lamp, the photoproducts of phenol in ice were analyzed by GC-MS and HPLC-EIS-MS. The photoproducts of direct photolysis of phenol were diphenylether and 2-hydroxybiphenyl. The photoproducts of phenol with the presence of H2O2 were catechol, hydroquinone, hydroxyhydroquinone, 2-hydroxybiphenyl, diphenylether, 2-phenoxyphenol, [1, 1'-biphenyl]-3, 3'-diol, [1,1'-biphenyl]-2, 2'-diol, dibenzofuran and there were four high molecular weight of new matter. The photoproducts of phenol with the presence of NO3- were 2-nitrophenol, 4-nitrophenol, catechol, hydroquinone, dibenzofuran, diphenylethe, 2-phenoxyphenol, 2-(2-hydroxyphenyl)cyclohexa-2,5-diene-1,4-dione, [1,1'-biphenyl]-3,3'-diol, [1,1'-biphenyl]-2,2'-diol and there were three high molecular weight of new matter. The photoproducts of phenol with the presence of NO2- were 2-nitrosophenol, 2-nitrophenol, benzoquinone, diphenylether, 2-hydroxybiphenyl, dibenzofuran, 2-phenoxyphenol, [1, 1'-biphenyl]-2, 2'-diol, [1, 1'-biphenyl]-3,3'-diol, 2-nitrodiphenylether, 2'-Hydroxyl-2-nitrodiphenylether and there were two high molecular weight of new matter.For phenol and phenol with the presence of H2O2, the photoproducts were produced mainly on hydroxylation products. For phenol with the presence of NO3- or NO2-, the photoproducts were produced mainly on nitration and hydroxylation products. The photoproducts characterization showed that more kinds of products are produced with the presence of H2O2, NO3- or NO2-, and they were complex structure and toxicity enhancement including nitro-group and hydroxyl group. Products in ice are different from those in water. There were one benzene ring products in water, but two or three benzene ring products in ice. The chemical properties of products in ice are stable and difficult to decompose. The results indicated the way of photo- conversion in ice was different from in water.Under the simulated solar irradiation, the phenol has not direct photolysis and indirect photolysis with the presence of H2O2 and NO2-. The effects of reagent con- centration, light intensity and pH value etc. have great influence on photoconversion of phenol. The photoconversion course follows the first-order kinetics equation. For phenol with the presence of H2O2 or NO2-, the results show that the photoconversion rate of phenol increases rapidly with the increasing of the initial concentration of H2O2, NO2-, and light intensity, and decreases with the increasing of the initial concentration of phenol. The stronger acid conditions inhibit the photoconversion of phenol, the stronger alkali conditions facilitate the photoconversion of phenol. The photoconversion rate of distilled water sample faster than the photoconversion rate of river water. With the presence of H2O2, There was no obvious effect of addition of Cl-. The addition of HCO3-, the photoconverison rate of phenol is decreased. With the presence of NO2-, there was no obvious effect of addition of Fe3+, Fe2+ or Cl- ,respectively. The addition of HCO3-, the photoconverison rate of phenol is decreased.Under the simulated solar irradiation, the photoproducts of phenol in ice were analyzed by GC-MS. The photoproducts of phenol with the presence of H2O2 were catechol and hydroquinone. The photoproducts of phenol with the presence of NO2- were 4- nitrophenol and the matter of which the molecular weight is 214. With the presence of H2O2, the photoproducts were produced mainly on hydroxylation products. For phenol with the presence of NO2-, the photoproduct was produced mainly on nitration product. The photoconversion of phenol in ice with the presence of H2O2 and NO2- under the simulated sunlight still has not been reported in the world.
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