Ammonia → Isophorone diamine

Participants

Reaction Steps

Through a tubular reactor (diameter 16 mm, packing height 50 cm, oil-heated double jacket), installed up-stream of the hydrogenation reactor and packed with 70.0 g (100 ml) of γ-aluminum oxide in the form of 1.5 mm extrudates there were passed upwardly, per hour, 40.4 g of a 50% solution of isophoronenitrile (purity 99.0%) in tetrahydrofuran and 303.0 g of liquid ammonia at a pressure of 250 bar and a temperature of 80° C. Hydrogen was then added to the stream at a rate of 60 standard liters (2.7 moles) per hour, and the effluent from the in-line imination reactor was passed upwardly through the hydrogenation reactor at a pressure of 250 bar and a temperature of 130° C. The effluent was depressurized to standard pressure, and the ammonia was distilled off. The hydrogenation product contained, apart from tetrahydrofuran, 96.4% of isophoronediamine and 0.6% of 1,3,3-trimethyl-6-azabicyclo[3.2.1]octane, as determined by gas-chromatographic analysis. The product obtained over an on-stream period of 121 hours was collected and separated by fractional distillation. There were obtained 2,371 g of isophoronediamine, corresponding to a yield of 95.1%.

Provenance & Evidence