Hazardous nitromethane

Nitronium tetrafluoroborate has been prepared by interaction of nitric acid, hydrogen fluoride, and boron fluoride in nitromethane.5 However, mixtures of nitric acid and nitromethane are extremely explosive.6,7 The present modification of the procedure, in which the medium is methylene chloride instead of nitromethane, was developed to avoid this hazard. It has not been published before. 

Nitromethane — Fire Hazards Flash Point (deg. F) 110 OC, 95 CC Flammable Limits in Air (%>) 7.3 LEL Fire Extinguishing Agents Water, foam, dry chemical, carbon dioxide Fire Extinguishing Agents Not To Be Used Not pertinent Special Hazards of Combustion Products Not... 

The instability and hazardous nature of alkali metal salts of nitromethane has been reported by Rowe, S.M. (Chilworth Technology Ltd.) (2000) Mettler Toledo Reaction Calorimetry and In-situ Spectroscopic Analysis Seminar, Chilworth Technology Ltd., Manchester, UK. 

Since many nitrogen-containing organic compounds are explosive, some mention is appropriate here of possible hazards in working with nitromethane. Occasionally, some evidence of decomposition, in the form of mild evolution of heat and gases, has been observed by the author in concentrated, acidified aldose-nitromethane reaction residues from which the bulk of the nitroalcohols had been separated. Such residues usually have been either discarded at once or stored at —20° when further crystallization was anticipated. Generally, it may be stated that the aldose-nitromethane condensation reaction does not involve serious explosion hazards. 

Hazards Wear gloves and insure proper ventilation when handling trifluoroacetic anhydride. Trifluoroacetic anhydride is corrosive, and can cause skin bums. Nitromethane is highly flammable. 

SAFETY PROFILE Mildly toxic by ingestion. A severe eye irritant. A skin, mucous membrane, and respiratory system irritant. Mutation data reported. Causes dermatitis. Dust is considered to be a significant industrial hazard. A common air contaminant. Violent reaction with maleic anhydride, nitroethane, nitromethane, nitroparaffins, nitropropane, phosphoms. Reaction with polychlorinated phenols + potassium nitrate forms extremely toxic products. See also CALCIUM COMPOUNDS. 

SAFETY PROFILE Poison by subcutaneous route. Moderately toxic by inhalation. A severe skin irritant. Mutation data reported. A strong base. Flammable gas at ordinary temperature and pressure. Very dangerous fire hazard when exposed to heat, flame, or sparks. Explosive when exposed to heat or flame. To fight fire, stop flow of gas. Forms an explosive mixture with nitromethane. When heated to... 

Flammable liquid. A very dangerous fire hazard when exposed to flame, heat, or oxidizers can react with oxidizing materials. To fight fire, use alcohol foam, CO2, dr chemical. Mixtures with nitromethane are explosive. May ignite spontaneously in contact with cellulose nitrate of high surface area. When heated to decomposition it emits highly toxic fumes of NO. ... 

SAFETY PROFILE Confirmed human carcinogen. Poison by subcutaneous route. Mutation data reported. Hazardous reaction with hydrogen peroxide. Presence of the oxide increases the sensitivity of nitroalkanes (e.g., nitromethane, nitroethane, 1-nitropropane) to heat. See also NICKEL COMPOUNDS and PEROXIDES. 

Efficient methods for the isolation and purification of crown ethers by complexing with alkaline-earth salts or with non-ionic compounds have been reported. These methods allow the purification of 18-crown-6 without the need for potentially hazardous distillations. Barium methanedisulphonate is the best salt, and nitromethane the best non-ionic reagent, for purification of 18-crown-6. 

Caution Prolonged oxidation of graphite in [ 104]" electrolytes may cause explosions, presumably owing to side reactions of C104- radicals. Explosion hazards are also present for the cathodic deposition of alkali metals in nitromethane—this is the counterreaction to the anodic formation of graphite salts in A X -nitromethane electrolytes. 

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