Question

Synthesis of Nitrobenzene

Objective

Introduction and background

Answer 1

Objective:

To prepare/synthesize nitrobenze by nitration of benzene with sulfuric acid and nitric acid.

Introduction:

• The production of nitrobenzene is one of the most dangerous processes conducted in the chemical industry because of the exothermicity of the reaction (ΔH = −117 kJ/mol).
• The nitration process involves formation of the nitronium ion.
• This is then followed by an electrophilic aromatic substitution reaction.
• Chemical Reaction involved :
  • HNO₃ + H⁺ ⇌ NO₂⁺ + H₂O

Background:

World capacity for nitrobenzene in 1985 was about 1.7×10⁶ tonnes. Nitrobenzene is a yellowish, oily, aromatic nitro-compound with an almond-like odor that emits toxic fumes of nitrogen oxides upon combustion. Nitrobenzene is primarily used in the manufacture of aniline, but is also used in the manufacture of lubricating oils, dyes, drugs, pesticides, and synthetic rubber.