Process for preparing ammonic glyphosate granules

A process for preparing water-soluble ammonic glyphosate granules comprising:

• a) addition of glyphosate acid, under wet cake form, to a solid Broensted base, which supplies ammonium ions, in amounts equal to a molar ratio base/acid between 0.8 and 1.1, optionally in the presence of coformulating agents;
• b) homogenization of the mixture prepared in a);
• c) addition of one or more surfactants, in a liquid form under stirring in amounts in the range 5%-50% by weight based on the glyphosate acid;
• d) mixing of the mass prepared in c) for a time lower than 10 minutes, until obtaining an extrudable mass wherein unreacted glyphosate acid, ammonium glyphosate and Broensted base are present;
• wherein, with respect to the initial acid amount, the unreacted glyphosate acid is present in an amount ranging from 70% to 10%, ammonic glyphosate is present a molar amount from 30% to 90%, and the corresponding amount of the unreacted base is present in the extrudable mass;
• e) extrusion by low pressure extruders of radial, basket or twin dome types of the mass obtained in d);
• f) drying until obtaining a granule having a residual moisture lower than 1% and completing salification of glyphosate.