Abstract: The porous granular material according to the invention comprises carbon, silica, water-soluble mineral salts and water-insoluble mineral salts, does not disintegrate in the presence of water and has a particle size of approximately 1 to 5 mm, preferably from 1 to 3 mm, in particular from 1 to 2 mm; a crushing strength, or mechanical strength, in the range of 0.75 to 1 MPa; a density of between 0.7 and 0.8; a BET specific surface area of between 100 and 200 m.sup.2 /g; a microporous volume of between 0.25 and 1 cm.sup.3 /g; and a carbon content of 8 to 11 weight %, the balance being essentially made up by a mineral matrix of base nature, comprising a crystalline phase of insoluble aluminosilicates.Application, in particular, to the purification of liquids, as a catalyst in oxidation reactions and in the manufacture of composite catalysts, in particular in petrochemistry.

Abstract: A process for the purification of waste water containing grease and soil, especially the effluent from wool-soaking and wool-washing, which comprises mixing the waste water with a heavy solvent; separating the emulsion formed to obtain degreased water, a small quantity of water-solvent emulsion, and solvent charged with greasy matter and soil; clarifying this solvent to separate the soil; subjecting the clarified solvent to an azeotropic distillation in the presence of water, to form an emulsion from which the greasy matter can be recovered, and a head product from which the solvent can be regenerated, and apparatus therefor.