- Red fuming nitric acid
Red fuming nitric acid (RFNA) is a storable
oxidizer used as arocket propellant . It consists mainly ofnitric acid (hydrogennitrogenoxygen3), also containing 13%dinitrogen tetroxide and 3%water . Thecolor of the resulting red fuming nitric acid is due to the dinitrogen tetroxide, which breaks down partially to formnitrogen dioxide .White fuming nitric acid does not contain free dinitrogen tetroxide.It is usually used with an inhibitor (with various, sometimes secret, substances, including
hydrogen fluoride ; any such combination is called IRFNA) because nitric acid attacks most container materials.It can also be a
monopropellant ; with substances likeammonium nitrate s dissolved in it, it can be used as the sole fuel in a rocket. It is not normally used this way however.During
World War II , the German military used RFNA in some rockets. The mixtures used were called S-Stoff (96% nitric acid with 4%ferric chloride ) and SV-Stoff (94% nitric acid with 6% dinitrogen tetroxide).Inhibited RFNA, used in modified SS-1 Scud missiles as an oxidizer by the Iraqi military during the 1991 Persian
Gulf War , was suggested as a possible factor causingGulf War Syndrome . However, this theory was later refuted.Compositions
*IRFNA IIIa: 83.4% HNO3, 14% NO2, 2% H2O, 0.6% HF
*IRFNA IV HDA: 54.3% HNO3, 44% NO2, 1% H2O, 0.7% HF
*S-Stoff: 96% HNO3, 4% FeCl3
*SV-Stoff: 94% HNO3, 6% N2O4
*AK20: 80% HNO3, 20% N2O4
*AK20F: 80% HNO3, 20% N2O4, fluorine-based inhibitor
*AK20I: 80% HNO3, 20% N2O4, iodine-based inhibitor
*AK20K: 80% HNO3, 20% N2O4, unknown inhibitor
*AK27I: 73% HNO3, 27% N2O4, iodine-based inhibitor
*AK27P: 73% HNO3, 27% N2O4, unknown inhibitorRelated
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White fuming nitric acid External links
* [http://www.npi.gov.au/database/substance-info/profiles/65.html National Pollutant Inventory - Nitric Acid Fact Sheet]
* http://www.astronautix.com/props/nitidjpx.htm
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