Patent ID: 8313619

Claim:
A method comprising: i) injecting oxygen (O 2 ) or air to a liquid aqueous biocidal mixture containing hydrogen peroxide (H 2 O 2 ) at an initial concentration of from 2 to 250 ppm; ii) supplying a suspension of magnesium oxide to the hydrogen peroxide containing mixture and adjusting a pH of the mixture containing hydrogen peroxide and magnesium oxide to a value of from 7.2 to 9.7, the magnesium oxide concentration within the mixture being from 2 ppm to 250 ppm; and iii) generating an increase in hydroxy radicals (OH − ) by irradiating the mixture containing hydrogen peroxide and magnesium oxide with UV light having a wavelength of from 190 to 390 nm; wherein the increase in hydroxyl radicals (OH − ) is characterized by at least a two fold increase in percentage (%) of salicylic acid (SA) conversion as compared to % conversion of SA conversion as a result of treatment with UV only.