Abstract: Purification of aqueous hydrogen peroxide solutions using conventional ion-exchange techniques can result in the hydrogen peroxide decomposing explosively. Much safer processes are obtained by restricting the contact between the resin bed and the hydrogen peroxide solution to a very short contact time, by employing a treatment chamber that is vented to the atmosphere and also by slurrying the resin bed. The bed is conveniently retained on a mesh that acts as a filter (13) preferably conical having an aperture (17) at its apex through which is introduced a small fraction of the solution countercurrent (10) to the main solution flow (9) in order to slurry the bed (19). The solution can be recycled through the same bed or a plurality of beds. Very high purification can be achieved and combined with improved safety of operation.

Abstract: Absorbent material comprising clay mineral particles, the particles comprising compacted masses of relatively smaller particles is found to have high absorbency which may be further increased by the use of additives such as silicates, pyrophosphates, swelling clays, polysaccharides or polyvinyl pyrrolidone. Preferred are smectites, attapulgite or sepiolite preferably in the form of particles in below 1.4 mm, preferably below 710 microns in the size range compacted into larger particles in the 710 micron to 4 mm size range. The absorbent particles are suitable for use as pet litter.

Abstract: A process for the manufacture of adsorbent clay mineral particles comprises first selecting clay mineral particles smaller than 2 millimeter in size, drying the clay mineral particles to a moisture content not exceeding 15% by weight and mixing the dried particles with from 0.2% to 5% by weight of a water dispersible colloid in water to form a mixture having a final moisture content not exceeding 15% by weight. The mixture is compacted in a press and the compacted material broken into masses of particles larger in size than the selected clay mineral particles and in the 710 micron to 4 millimeter size range. The product of the process is useful for example as a litter.