Process for preparing aminomethane

Abstract

A mixture of methylamine and methanol is subjected to a vapor phase catalytic reaction with ammonia in the presence of a zeolite catalyst. The thus-obtained reaction mixture is, after separating unreacted ammonia in an ammonia separation column, trimethylamine in a trimethylamine separation column and water in a dewatering column, fed to a monomethylamine / dimethylamine separation column to recover monomethylamine from the top of the column and dimethylamine from the bottom of the column while condensing distillate gas from the top of the column in a condenser.

Description

technical field [0001] The present invention relates to the method for producing methylamine by the vapor phase contact reaction of formaldehyde and ammonia. More specifically, the present invention relates to an economical manufacturing process by reducing energy consumption during distillation in the methylamine manufacturing process. Methylamines are important chemical intermediates as raw materials for various solvents, pharmaceuticals, rubber chemicals, and surfactants. Background technique [0002] Methylamine is generally produced by reacting formaldehyde and ammonia in the gas phase at high temperature (about 400°C) by dehydration and amination of alumina, silicon-alumina, etc. in the presence of a solid acid catalyst. Typically, a mixture of dimethylamine, monomethylamine, and trimethylamine is formed in this reaction. In addition, since the required amount of these methylamines is very small except for dimethylamine, after separating the dimethylamine of the reac...

AI Technical Summary

Problems solved by technology

[0005] In this way, since trimethylamine forms a complex azeotropic system with ammonia, monomethylamine and dimethylamine, its separation requires very complicated distillation operations and large-scale devices, resulting in very large industrial energy consumption in the methylamine manufacturing process. question