High Power UV and VUV Excilamps and Their Applications

Abstract

molecules and I atoms was obtained in rare gas or in rare gas-Br 2 (Cl 2 , I 2 ) mixtures. Study of radiation parameters and lifetime period of the manufactured barrier discharge excilamps has been performed.

Environmental Implications of Hydroxyl Radicals (•OH)

“…185 These lamps also opened up the possibility for water photolysis to be considered among the potential oxidation processes for wastewater treatment, although the Hg emission line at 185 nm is more often used in laboratory applications. 186,187 . 188 A consequence of the fact that • OH is produced by irradiation of the solvent is that the water ability to absorb VUV radiation, combined with its high molar concentration, makes H 2 O an optically thick medium in the VUV range.…”

“…The production of • OH from H 2 O/OH – by VUV irradiation has been made easier by the availability of cost-effective excilamps, based on excimers or exciplexes of Xe 2 , Cl 2 , I 2 , XeBr, KrCl, and XeCl . These lamps also opened up the possibility for water photolysis to be considered among the potential oxidation processes for wastewater treatment, although the Hg emission line at 185 nm is more often used in laboratory applications. , Absorption of VUV radiation splits H 2 O/OH – into • OH and H • or • OH and e – . The reductive character of hydrogen atoms and solvated electrons, which could compensate for the oxidizing activity of • OH, is minimized in aerated aqueous solutions by O 2 scavenging to yield HO 2 • /O 2 •– …”

Degradation of a Model Naphthenic Acid, Cyclohexanoic Acid, by Vacuum UV (172 nm) and UV (254 nm)/H2O2

“…A dielectric barrier discharge Xe 2 * excilamp (Model BD-P-barrier discharge portable, Institute of High Current Electronics, Tomsk, Russia 20 ) with dimensions 26.5 × 7.7 × 77 cm (length × width × height) including a cooling fan was used for the VUV study. The lamp was placed in a collimated beam apparatus designed specifically for VUV experiments.…”