Process for production of granular material for water treatment

摘要

A granular water treatment material and a process for the production thereof, the material being in the form of spherical granules, each having a thermoplastic polymeric matrix (1) and a more dense adjuvant in the form of micro-grains (3) dispersed in the matrix; each granule has on the surface a porosity in the form of micro-cavities (4) and cationic hydrophilic sites distributed on the surface; the process includes providing a mixture of an oxidizable thermoplastic resin and an adjuvant in powdered form, heating the mixture to make it plastic, extruding the plastic material to a diameter corresponding to the size of the granules to be obtained and cutting the extrusions to a length equal to this diameter, achieving a beading of the extruded pieces, oxidizing the surface of the spherical granules thus obtained, then ionically grafting a cationic polyelectrolyte to the surface of said granules.