(Hive Bee)
11-11-02 07:53
No 378615
      hexamine to methylamine a old new way?
(Rated as: excellent)

I stumbled over this quite old (1893) german  Patent DE073812  on the production of methylamine from hexamethylentetrenamine.

They tell no yields but I would be interested if somebody knows more on this way or has tried it already:

100 parts (what does this say?) of hexamethylenamine are dissolved in 2 to 3 liters water at roomtemperature. Than over 3 to 4 hours the for the reduction necessary amounts (they don´t disclose how much this is frown) of HCl and zincdust are added. After 24 hours the solution gets basified and the methylamine steamdistilled in diluted HCl to yield methylamine.HCl.

Then follows a part on making dimethylamine from methylamine what tells me that the first procedure should yield quite pure methylamine.

Comments please!
Sounds not bad for me, roomtemperature and if the steam is going into water and not HCl you should get aqueous methylamine what may be preferable sometimes.


now or never
(Synaptic Self-Mutilator)
11-11-02 13:30
No 378676
      Just a guess  Bookmark   

Hexamine is soluble at 20g/100g water. If I was attempting this reaction I'd want to use something this concentrated. However, because you've got a lot of zinc to add, they may have done the reduction in a much more dilute solution.

... perhaps they meant to write 100 parts hexamine per 2000 parts water? ("parts" is a measure of weight)
(Hive Bee)
11-12-02 07:29
No 378923
      the original text  Bookmark   

cited from the patent:

100 Theile Methylenamin (oder ein Gemisch von entsprechenden Mengen Formaldehyd und Ammmoniak) werden mit 2 bis 3l Wasser verdünnt.

Yes, 1893 is quite a time ago.

...followed by adding HCl and zincdust over 3 to 4 hours, after 24 hours basifying and steam extraction into diluted HCl to gain methylamine.HCl by evaporation.

They didn´t use to make a lot of words these days it seems. <sigh>

(Chemicals in authentic spelling now)
The same procedure with Methylamin and Formaldehyd gains Dimethylamin, they state and Aethylaldehyd with Ammoniak gains Aethylamine.

Must have been hard boys, these precursors of HOECHST and IG-Farben.


now or never
(Hive Bee)
11-12-02 15:56
No 378970
      Re: Methylamine production  Bookmark   

This may or may not help,read Post 306610 (java: "methyl amine by catalytic hydrogenation", Chemistry Discourse), I haven't tried it but plan to since SWIJ has shifted his efforts to the P2P route and will need this on his way.

Saludos(greetings), from Latin America