1. Description of the "medium temperature" process

1.1 Principle

The controlled oxidation of orthoxylene or naphthalene with air between 350 and 430 ˚C (hot spot), in a fixed-bed vertical tubular reactor, leads to the following chemical reaction:

The enthalpies of reaction (taking into account by-products and combustion) are respectively :

• ΔH ₁ = - 15.0 MJ per kilogram of orthoxylene ;

• ΔH ₂ = - 16.7 MJ per kilogram of naphthalene.

The main reaction...