Patent ID: 7518020
Filing Date: 2009-04-14
Classification: C07C

Abstract:
1. A process for preparing methylamines comprising gas-phase reaction of methanol and ammonia as starting materials at a pressure in the range from 15 to 30 bar in the presence of a heterogeneous catalyst, which further comprises vaporizing the starting materials in one or more heat exchangers, superheating them to form a feed gas stream and subsequently feeding this into a reactor, with the starting materials either being mixed in the feed stream to one of the heat exchangers or at any other position on the heat exchanger, and taking off a product gas stream comprising monomethylamine, dimethylamine and trimethylamine and also reaction by-products from the reactor, wherein the reactor inlet temperature of the starting materials is controlled to a temperature in the range from 360° C. to 370° C. by passing part or all of the feed gas stream or product gas stream through an adjustable valve in order to vary the pressure.