The mixture of Dinitrotoluene isomers is a very valuable raw material for the plastics chemistry, which after hydrogenation (to TDA) and subsequent phosgenation (to TDI) is finally processed to polyurethane.

DNT plants by MEISSNER 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 with small reactor volumes. The circulation pumps used in the reactors provide for an optimum conversion of the reactants and thus a DNT of uniformly high quality.

Thanks to the special design of the MEISSNER nitration reactors, MEISSNER is able to supply DNT plants with a capacity of up to 50 t of DNT/hour in one line.

In MEISSNER DNT plants, nitration is carried out in two steps. First, Toluene is nitrated to produce MNT, and then MNT is nitrated to produce DNT. After each nitration step the product is separated from the respective acid in dynamic separators and is then further processed. The raw DNT is automatically conveyed to the washing unit consisting of MEISSNER compact washing apparatus, which perform the product washing as well as the separation of the product from the respective washing medium.

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

Additionally to the DNT plant, MEISSNER as main contractor also offers the spent acid regeneration plant performing the recovery of concentrated Sulphuric Acid with recovery of Nitric Acid and organics, as well as an economical waste water treatment plant for the disposal of toxic nitrocresols contained in the DNT waste water so that a biologically degradable waste water is obtained.