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How is nitrobenzene detected?
The detection of nitrobenzene is based on its partial reduction with zinc in slightly acidic medium to yield phenylhydroxylamine, acid-catalyzed rearrangement to form a mixture of 2- and 4-aminophenol, and formation of indophenol blue by 4-aminophenol on oxidative coupling with an alkaline phenol solution.
What is nitrobenzene called?
Nitrobenzene is also known as oil of Mirbane.
How do you make nitrobenzene?
Nitrobenzene is produced commercially by the exothermic nitration of benzene with fuming nitric acid in the presence of a sulfuric acid catalyst at 50 to 65°C. The crude nitrobenzene is passed through washer-separators to remove residual acid and is then distilled to remove benzene and water.
How can aniline reduce nitrobenzene?
It is generally accepted that the reduction of nitrobenzene to aniline consists of two main steps: first, nitrobenzene is reduced to phenylhydroxylamine (PHA) through a 4-electron exchange, with nitrosobenzene (NSB) as an intermediate. Then, a 2-electron reduction step converts PHA to aniline (Scheme 1) [16,17].
How is nitrobenzene produced?
Why is nitrobenzene harmful?
Repeated exposures to a high concentration of nitrobenzene can result in a blood condition called methemoglobinemia. This condition affects the ability of the blood to carry oxygen. Following such an exposure, the skin may turn a bluish color. This may be accompanied by nausea, vomiting and shortness of breath.
What is the directing effect of nitrobenzene?
The directing effect of nitrobenzene is 93% meta, 6% ortho and 1% para. The formation of ortho, meta and para-dinitrobenzene is as follows: Nitrobenzene is very toxic and it can readily absorb through the skin. So precaution must need to be taken during and after the reaction.
How do you nitrate nitrobenzene?
The nitration is carried in a stainless steel pan fitted with a stirrer and cooling-water pipe to remove heat generated by the reaction and to maintain the temperature at 50°C. When nitration is complete, the nitrobenzene layer is separated from the spent acid by decantation.
What is nitrobenzene used for in agriculture?
Nitrobenzene is also used in Kerr cells, as it has an unusually large Kerr constant. Evidence suggests its use in agriculture as a plant growth/flowering stimulant. Aside from its conversion to aniline, nitrobenzene can be selectively reduced to azoxybenzene, azobenzene, nitrosobenzene, hydrazobenzene, and phenylhydroxylamine.
Is nitrobenzene classified as a carcinogen?
(1) EPA has classified nitrobenzene as a Group D, not classifiable as to human carcinogenicity. Nitrobenzene is an oily yellow liquid with an almond-like odor. (1) The odor threshold for nitrobenzene is 0.018 parts per million (ppm).