Published August 1993
Melamine Chemicals' M-II process simplifies the production of melamine over other anhydrous process in which urea is pyrolyzed to melamine. In this process melamine is recovered directly from the melamine melt as a dry powder, thus saving capital and energy intensive recrystallization steps that are used in other processes. The product of this process has a purity of 96 wt%, whereas other processes produce a product having greater than 99.8% purity. High purity melamine is preferred by melamine-formaldehyde resin producers because the purity of the melamine raw material influences the physical properties of the resulting resins and affects processing times. However, it is claimed in patents to Melamine Chemicals that lower purity melamine can be substituted in the production of melamine-formaldehyde resin if resin reactor conditions (e.g., pH) are carefully controlled. In this review, we present a preliminary process design and economics for Melamine Chemicals' M-II process. We also compare the economics with those for Stamicarbon's low pressure (catalytic) process.