Technology

Hydrogenation of Dinitrotoluene (DNT) to Toluene Diamine (TDA) is accomplished in a Continuous Process using a Palladium-Platinum on Carbon or other Metal Heterogeneous Catalyst System. The Hydrogenation is thus a Multiphase System of Dinitrotoluene Melt, Catalyst, and Toluene Diamines in Water and Hydrogen Gas. Hydrogen Pressure can vary from ca. 100 psig to over 500 psig. The Hydrogenation Process is exothermic and Temperature is carefully controlled (ca. 120 °C). Water and Orthoisomers are removed by Distillation. The Mechanism of Hydrogenation to the Polyamines is very complex, going potentially through Hydroxylamine, Azo, and Hydrazine Intermediates among several others. The overall Reaction proceeds according to the equation: DNT + 6 H₂ → TDA + 4 H₂O