Process for preparing 3-aminomethyl-3,5,5-trimethylcyclohexylamine

A process for preparing isophoronediamine IPDA, the process comprising:

• (i) reacting acetone via a catalyzed aldol condensation in a reactor, thereby obtaining a reaction product comprising isophorone,
• (ii) working-up the reaction product, thereby obtaining a stream of value
• (iii) hydrolyzing the stream of value in a hydrolysis apparatus,
• (iv) separating the stream of value into an organic fraction and an aqueous fraction,
• (v) recovering isophorone from the organic fraction,
• (vi) distilling the aqueous fraction in a distillative workup apparatus comprising a top and a bottom,
• (vii) passing vapors from the top of the distillative workup apparatus onward into the hydrolysis apparatus,
• (viii) reacting isophorone with HCN via a base-catalyzed reaction, thereby obtaining isophoronenitrile IPN, and
• (ix) reacting IPN via a catalytic hydrogenation, a catalytic reductive amination, or both in the presence of ammonia, hydrogen, at least one catalyst, and optionally a solvent or a solvent mixture, thereby obtaining IPDA,
• wherein a cyanide ion concentration in a reaction mixture sent to the catalytic hydrogenation is of from 200 ppmw to 5000 ppmw, based on the IPN used.