Process for increasing the specific area and the activity of a sorbent material comprising aluminosilicates, and material obtained.

摘要

To prepare or activate an adsorbent material consisting of partially modified aluminosilicates, particles of anamorphosed rocks containing at least 17% by weight of barren materials, recovered from coal residues, are subjected to an oxidation by roasting in air in a fluidised bed furnace at a temperature of between 350 and 800 DEG C. Alternatively the particles of anamorphosed rocks can be subjected to an oxidation with the aid of aqueous hydrogen peroxide or in aqueous phase in the presence of air or optionally pressurised oxygen, at a temperature lower than or equal to the boiling temperature of the reaction mixture. The oxidation has the effect of removing the free carbon and of oxidising the ferrous iron ions Fe<+><+> to ferric iron ions Fe<+><+><+>. Particles thus obtained have a particle size which is so fine that they prevent water percolation. By binding these particles together with 0.1 to 2% of chemical polymers, cements or binders of the pyroaurite type, a rapid filtration and an increase by more than 120% in the absorption capacity is brought about.