Nitrobenzene
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Nitrobenzene, also known as nitrobenzol or oil of mirbane, is a poisonous organic compound with an almond odor and chemical formula C6H5NO2. It may be found as either bright yellow crystals or an oily insoluble liquid.
It is used as a solvent and as a mild oxidizing agent. It is most frequently used specifically in the manufacture of aniline, but also used in the manufacture of insulating compounds and polishes.
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Characteristics
| Characteristic/Property | Data | Reference |
|---|---|---|
| CAS No. | 98-95-3 | |
| Common Synonyms | nitrobenzol; oil of mirbane | U.S. EPA 1994 |
| Molecular Formula | C6H5NO2 | |
| Physical State | liquid | U.S. EPA 1985 |
| Molecular Weight | 123.06 g/mol | U.S. EPA 1985 |
| Melting Point | 5.85 °C @ 1 atm | U.S. EPA 1985 |
| Boiling Point | 210.9 °C @ 1 atm | U.S. EPA 1985 |
| Water Solubility | 1.9 g/L @ 20 °C; 2.1 g/L @ 25 °C | U.S. EPA 1985 |
| Density | 1.199 kg/L @ 24 °C | U.S. EPA 1985 |
| Vapor Density (air = 1) | 4.1 | U.S. EPA 1985 |
| Carbon matter partition coefficient Koc | 36-650 (estimated) | U.S. EPA 1987 |
| log (octanol-water partition coefficient) log Kow | 1.85 | U.S. EPA 1987 |
| Vapor pressure (20 °C) | 20 Pa (0.15 mmHg) | U.S. EPA 1987 |
| Vapor pressure (25 °C) | 36 Pa (0.27 mmHg) | U.S. EPA 1987 |
| Reactivity | flammable | |
| Flash point | 88 °C (closed cup) | Budavari 1989 |
| Henry's Law constant (25 °C) | 2.33 J/mol 2.3×10-5 atm·m³/mol | U.S. EPA 1985 |
| Fish bioconcentration factor | <10-15 (measured in the golden orfe) | U.S. EPA 1985 |
| Odor threshold | perception, 18.2 µg/m³ (3.55 nmol/mol) | Verschueren 1983 |
| threshold, 9.7 mg/m³ (1.9 µmol/mol) | U.S. EPA 1985 | |
| Conversion factors (in air) 1 ppm by molecules = 1 µmol/mol | 1 µmol/mol = 5.12 mg/m³ 1 mg/m³ = 0.195 µmol/mol | Verschueren 1983 |
Uses
While nitrobenzene is primarily used in the production of aniline and aniline derivatives, such as methyl diphenyl diisocyanate (MDI), it also finds use in the manufacture of rubber chemicals, pesticides, dyes, and pharmaceuticals. Nitrobenzene is also used in shoe and floor polishes, leather dressings, paint solvents, and other materials to mask unpleasant odors. Substitution reactions with nitrobenzene are used to form m-derivatives (Mannsville 1991; Sittig 1991). Redistilled, as oil of mirbane, nitrobenzene has been used as an inexpensive perfume for soaps. A significant merchant market for nitrobenzene is its use in the production of the analgesic acetaminophen (Mannsville 1991).
Production
There were four producers of nitrobenzene in the United States in 1991: First Chemicals Corporation, Mobay, DuPont Chemicals, and Rubicon Inc. In 1991, the estimated total production capacity of nitrobenzene in the U.S. was 1,360 million pounds (617 gigagrams) (Mannsville 1991).