Methylamines

Methylamines can be synthesized by alkylating ammonia with methyl halides or with methyl alcohol. The reaction with methanol usually occurs at approximately 500°C and 20 atmospheres in the presence of an aluminum silicate or phosphate catalyst. The alkylation does not stop at the monomethylamine stage, because the produced amine is a better nucleophile than ammonia. The product distribution at equilibrium is: monomethylamine MMA (43%), dimethylamine DMA (24%), and trimethylamine TMA (33%):

To improve the yield of mono- and dimethylamines, a shape selective catalyst has been tried. Carbogenic sieves are microporous materials (similar to zeolites), which have catalytic as well as shape selective properties.

Combining the amorphous aluminum silicate catalyst (used for producing the amines) with carbogenic sieves gave higher yeilds of the more valuable MMA and DMA.