Dinitrotoluene

The mixture of Dinitrotoluene isomers, produced either starting from Toluene via MNT to DNT, or starting from MNT, is a very valuable raw material for the plastics chemistry and is finally processed to polyurethane after hydrogenation (to TDA) and subsequent phosgenation (to TDI).

Meissner Dinitrotoluene plants are characterized by their circulation reactors, which have been developed especially for nitration purposes, and which ensure a high degree of security due to their large cooling areas for a small reactor volume. The circulation pumps used in the reactors accomplish an optimum conversion of the reactants, in this way providing a constantly high quality of DNT.

The special design of the Meissner nitration reactors enables Meissner to supply DNT plants with a capacity of 30 t DNT / hour and more in one line.

In Meissner DNT plants, based on Toluene and DNT mixed acid, nitration is carried out in two steps. After each nitration step the product is separated from the respective acid in dynamic separators and then further processed. The DNT final acid is returned into the first nitration step. The raw DNT is automatically conveyed to the washing unit consisting of Meissner compact washing apparatuses performing the washing as well as the separation of the product from the washing medium.

Meissner DNT plants do not generate any acidic, nitrate loaded waste water, since the Nitric Acid contained in raw DNT is regenerated and re-used.

Meissner as main contractor offers, along with the DNT plant, also the spent acid regeneration plant for regeneration of concentrated Sulfuric Acid with recovery of Nitric Acid and organics, as well as an economical waste water regeneration plant for the removal of the toxic nitrocresols contained in the alkaline DNT waste water, in order to obtain a biologically degradable waste water.