Glaser's "Chemistry is in theNews"
To Accompany Wade Organic Chemistry 4/e.
Chapter 19. Amines.
Between 1988 and 1992, there were 6900 chemical accidents annually, which is more than 300% greater than the average number of aviation accidents. The explosions at Hanford's Plutonium Finishing Plant (PFP) and Concept Science Inc. are prime examples of the hazards of chemical use in industry. The probable cause of the explosion at Concept Science Inc. was the distillation of hydroxylamine. Concept Science Inc. is a large manufacturer of free-base hydroxylamine. Besides its use for computer chip etching, hydroxylamine has a variety of uses. For example, it is used in the synthesis of antibiotics, production of pesticides, plastics, photography, paints and codings, as well as in rubber.
In the many uses in industry, hydroxylamine can be a hazardous material. Therefore precautionary measures must be enforced to ensure safety. There is a large quantity of information regarding the safe handling of hydroxylamine and other hazardous materials, such as the Material Safety Data Sheets(MSDS) and the National Fire Protection Association(NFPA).
In concentrations greater than 50%, hydroxylamine solutions can be potentially hazardous. Other causes of explosions by hydroxylamine could be caused by the exposure to incompatible conditions such as heat, oxidizing agents, Potassium Dichromate, Chromium Trioxide, Zinc, Calcium, and Copper. Thermodynamically, the decomposition of hydroxylamine produces 1240 cal/g, which is approximately as energetic as TNT. Exposure to hydroxylamine fumes, nitric oxides, and its products can cause chemical burns, nausea, dizziness, and headaches. Long term effects or repeated exposure may cause skin sensitization and affects the blood causing anemia.
The tragic loss of the five lives could have been prevented with proper management of such a volatile compound.Pertinent Text References
Question 1: Draw the Lewis-Kekule structure of NH2OH. Describe the hybridization and molecular geometry.
Question 2: List the possible oxidizing agents involved in the explosion. (Hint see pg. 875)
02, H2O2, MCPBA(m-chloroperoxybenzoic acid), ArCO3H
Question 3: The equation for the decompostion of NH2OH is given as: 2 NH2OH --> N2 + H2 + 2 H2O. Explain whether this reation is product favored or reactant favored and why?
Product favored (exothermic) 1240cal/g. Thermodynamically favors decompostion.
Question 4: What are hazard ratings for NH2OH and how is NFPA system used?
Health 2 : Flammability 0 : Reactivity 3
Question 5: How can chemical companies regulate safe use of potentially dangerous compounds?