Hydrogen peroxide formation from the photooxidation of formaldehyde and its presence in rainwater

Abstract

The photooxidation of formaldehyde with sunlamps (E_{max =} 3100 Å) produces hydrogen peroxide at varying concentrations depending upon the amount of water vapor present. It is postulated that the variable production of H₂O₂ is a result of condensation on the reactor surface. Rainwater samples were also analyzed for H₂O₂. Summer rain in the Triangle area of North Carolina contained as much as 200 ppb (w/w) of H₂O₂. Rainwater collected in December contained much less H₂O₂, usually 2–8 ppb. The lower concentration found in the colder conditions is attributed to a decrease in photochemical activity.