| Phenol is a prototype poison ,which are toxic to allliving creature that includes body ,water resources ,aquaticorganism and crops .A large amount of phenol waste watercomes from different sources with potential severe impactto environment.The mostly methods of dispose phenol wastewater are :physicochemical treatment and chemical treatmentand biological treatment. Advanced Oxidation Technologics(AOTs) has been studied as a hotspot problem. AOTs whichmostly characteristic is produced hydroxyl radical (HO·)is a effective means to dispose organism infectant.However ,the lifetime of hydroxyl radical is veryshort ,so it is difficult to study its formation rules .Atpresent ,the mostly used four analysis methods for isolateddetection of hydroxyl radical areESR ,HPLC ,electro-chemical and chem ilum inescence.Themostly modes of creat HO·are ozonation process, Fentonoxidation process ,optical semiconductor materials,ultrasonication and electro-chemical.Ozonation treatmentof waster water has the best foreground to apply in ourcountry because its has lowly cost and reaction condition.In this study ,a homemade ozone generator and ultravioletlight were used to treat phenol water.The half life of HO·is 10-10s so it is too difficult todetermine directly .In the system of O3/UV,SA was used as a"probe" to capture HO·in determined the concentration of2,5-DHBA --the output of SA had been hydroxylated byHPLC ,then the concentration of HO·could be estimatedindirectly.In the system of O3/UV,reactant concentration ,pHvalue and reaction time are the effect factors of creatingHO·.A initial concentration 60μmol/L ,pH value 7.92 SAsolution was treated in O3/UV system ,the concentration of2,5-DHBA increased with time gradually, reached the highestconcentration when the operation system had been workingfor 60s,that is ,it is a quick balance process ,itsconcentration was 0.194mg/L at 75s.A initial concentration120μmol/L ,pH value 7.92 SA solution was treated for75s ,the detected concentration of 2,5-DHBA is 0.222mg/L.Itcan be seen from the result that the higher concentrationof reactant the more HO · would be captured.A initialconcentration 60μmol/L ,pH value 11.27 SA solution wastreated under O3/UV for 75s ,the concentration of 2,5-DHBAwas 1.453mg/L.That means that the yielding is high in analkaline solution.4L of phenol solution with pH value 6.38;initialconcentration: 50mg/L,100 mg/L,150 mg/L were treated underO3/UV for 30min at 20℃,the degradation rate were 70.52%,52.71%,36.50% ,that means the degradation promoted atlower initial concentration.4L of phenol solution withinitial concentration 100mg/L adjusted pH value to 4.30 and9.93 which were treated under O3/UV for 30min at 20℃ ,thedegradation rate were 33.37% and 99%.A large amount ofHO·were produced under alkaline condition ,it was the mostlyfactor to dispose phenol ,so the degradation rate of phenolpromoted largely.4L of phenol solution with initialconcentration 50mg/L adjusted pH to 9 which were treatedunder O3/UV for 30min at 20℃,30℃,40℃,50℃,the degradationrate all beyond 90%,that is to say, temperatures have a smallimpact on the phenol degraded .Quinone is a intermediateproduct of phenol degradation ,it has been determined byultraviolet spectrophotometer .The solution acidity andyielding of HO· were declined when small molecule organicacids were produced from the degradation ,so the smallmolecule organic acids were degraded slowly .So thedegradation rate of COD were lower to that of phenol .4L of phenol solution with initial concentration 50mg/LpH value 6.38 COD 120 mg/L was treated under O3/UV for 30minat 20℃,the degradation rate of phenol was 65.2% and thatof COD was 30%。When the pH value was adjusted to 10.01, phenolcould not be determined ,COD was declined 60%, pH value was8.34,that is to say ,the degradation of COD could be promotedunder alkaline condition.A sample which was collected from a chemical plant withphenol concentration 205.95mg/L, COD 629mg/L,pH value 5.5was adjusted to 10.03 ,treated 120min under O3/UV ,thedegradation rate of phenol was 82.3%,COD was 336,pH valuewas 3.34.
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