Method for producing melem-free melamine and quenching agents

US7176309B2 · kind B2 · utility

Assignee

• AMI Agrolinz Melamine International GmbH · AT

Inventors

• Frank Schröder · Obernburg, DE
• Wolfgang Ruech · Ried im Innkreis, AT
• Christoph Neumüller · Ansfelden, AT
• Ferdinand Koglgruber · Linz, AT
• Hans Wagner · Wien, AT

Key dates

• Filing date: Nov 14, 2002
• Grant date: Feb 13, 2007
• Expiry date: Nov 14, 2022

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07D251/62
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

The invention relates to a method for producing melem-free melamine by means of aqueous processing of a melted mass of melamine which is obtained using a high-pressure method. According to the inventive method, the melted mass of melamine is quenched by means of an aqueous solution containing alkalis, following the isolation of the off-gases, and is directly transferred into an aqueous alkaline melamine solution, out of which the melamine is then crystallized. The invention thus enables melamine to be obtained, with a melam content of less than 1000 ppm and a melem content of less than 50 ppm. The invention also relates to a quenching agent.