Secondary Organic Aerosol Formation In A Photoreactor From Ethyl Acetate And Ozone

This article uses the self-made smoke chamber to verify the process and affecting factors of the photooxidation of ethyl acetate with ozone,after test the characterization of smoke chamber.Simulated the formation process of secondary organic aerosols from the photooxidation of ethyl acetate by using the mechanism of MCMv3.2,FACSIMILE software combining the experimental results.The experiment of photo-oxidation of ethyl acetate with ozone is carried out under the condition of the control of ozone(0~250mg/m3),ethyl acetate(50~120mg/m3),temperature(323±2K)and relative humidity(30~45%).The study found that ozone and light is necessary for ethyl acetate photochemical reaction;ozone concentration is the key factor for ethyl acetate to transformate into secondary organic aerosols.When there is no ozone exist,humidity has less effect on SOA formation.When the concentration of ethyl acetate and humidity are higher,ethyl acetate could transform into the secondary organic aerosol.When the ozone is in the range of 120~250 mg/m3 and ethyl acetate is 50~120mg/m3,SOA could form in the first 30 min.The higher humidity,the faster formation rate of aerosol would be.Comparing the experiment result and the simulating by MCMv3.2,ozone and UV light is necessary for ethyl acetate photochemical reaction.Humidity acts a key factor to SOA transformation.Light influence is greater than ozone when the concentration of ethyl acetate are similar.The bigger humidity,the faster for nuclear reactions would be,which is the more match of the MCM simulation results.The higher the ozone concentration,the greater deviation of balance time and simulation by MCMv3.2 would be.