A large-scale outdoor atmospheric simulation smog chamber for studying atmospheric photochemical processes: Characterization and preliminary application

Understanding the formation mechanisms of secondary air pollution is very important for formulation control countermeasures in China. Thus, a large-scale outdoor atmospheric simulation smog chamber was constructed at Chinese Research Academy Environmental Sciences (the CRAES Chamber), which designed simulating photochemical processes under conditions close to real environment. The consisted 56-m3 fluorinated ethylene propylene (FEP) Teflon film reactor, an electrically-driven stainless steel alloy shield, auxiliary system, and multiple detection instrumentations. By performing series characterization experiments, we obtained basic parameters chamber, such as mixing ability, background reactivity, wall loss rates gaseous compounds (propene, NO, NO2, ozone) aerosols (ammonium sulfate). Oxidation experiments were also performed study ozone organic aerosol (SOA), including α-pinene ozonolysis, propene 1,3,5-trimethylbenzene photooxidation. Temperature seed effects on vapor SOA yields this work: higher temperature presence could reduce loss; yield found depend inversely temperature, increase yield. suggested be used interaction between gas phase walls. results above showed that reliable meet demands investigating tropospheric chemistry.