Improved process for the purification of melamine and relative equipment

The present invention relates to an improved process for the purification of melamine obtained by synthesis from urea which comprises the following steps: a) bringing raw melamine containing impurities of polycondensates and other by-products of the synthesis reaction, into solution, obtaining a solution/suspension in which the insoluble products are dispersed; b) subjecting the solution/suspension thus obtained to treatment to remove the CO 2 dissolved, reducing its concentration to values lower than 0.5% by weight; c) treating the solution/suspension obtained in step b), having a content of CO 2 lower than 0.5% by weight, with ammonia in a quantity ranging from 1 to 15%, preferably from 3 to 9% by weight, at a temperature ranging from 110 to 180°C, preferably from 130 to 140°C; d) putting the solution leaving step c) in contact with a solid catalyst, under the same conditions as step c). The present invention also relates to the equipment for effecting said process.