OH generation in steam-air pulsed corona
- Lawrence Livermore National Lab., CA (United States)
The measurement of OH concentration in a pulsed corona discharge through a steam-air mixture is compared with a chemical kinetics model. The original motivation was to develop a technological hydroxilizer for oxidizing gas pollutants to acids. Time dependent measurements of the 3064 {angstrom} emission of OH indicate a production of nearly 4 ppm ({approx} 10{sup 14} cm{sup -3}) within a spark. This measurement was accomplished by a 1 ns resolution photomultiplier with a 100 {angstrom} filter centered at 3080 {angstrom}. The discharge occurs across a 1 cm coaxial gap between a central anode tube and an outer cylindrical cathode cased in glass and at ground potential. The water-air mixture is of equal proportion and at 1 atmosphere. Pulsed voltage of 38 kV and 60 ns risetime produces a 60 A, 20 ns spark. The model predicts comparable OH production by dissociation in the air-water mixture after 100 ns of 10{sup 12} electrons/cm{sup 3}. The electron density is set to zero during the subsequent 100 {mu}s in the model, and thereafter OH is seen as a short-lived reaction product of HO{sub 2} with O and N atoms. The sequence of reaction is: 100 ns of dissociation to peak OH concentration, 0.2 {mu}s for hydrogen atom loss and HO{sub 2} formation, 20 {mu}s for O atom loss and O{sub 3} formation, beyond 20 {mu}s NO formation from N atoms with OH and HO{sub 2}. In the model, HO{sub 2} ultimately decays by slowly forming H{sub 2}O{sub 2}, so it may be viewed as a stable fuel which produces OH when combined with atomic oxygen or nitrogen.
- Research Organization:
- International Union of Pure and Applied Chemistry; American Physical Society, New York, NY (United States)
- DOE Contract Number:
- W-7405-ENG-48
- OSTI ID:
- 223691
- Report Number(s):
- CONF-950875-Vol.2; TRN: 96:002546-0014
- Resource Relation:
- Conference: 12. international symposium on plasma chemistry, Minneapolis, MN (United States), 21-25 Aug 1995; Other Information: PBD: Jul 1995; Related Information: Is Part Of 12th International symposium on plasma chemistry. Proceedings, Volume 2; Heberlein, J.V.; Ernie, D.W.; Roberts, E.D. [eds.] [Minnesota Univ., Minneapolis, MN (United States)]; PB: 615 p.
- Country of Publication:
- United States
- Language:
- English
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