Non-Visible Activated Carbon in Absorbent Materials

Abstract

The present invention teaches an absorbent material with powdered activated carbon which is substantially light-colored without using color masking agents or hiding. This invention addresses the need in the field for an absorbent material with improved odor-controlling properties, that maintains such properties for longer periods of time and where the absorbent material maintains a light-colored appearance without the addition of color-masking agents. Suitable methods for creating the absorbent materials include a pan agglomeration process, a high shear agglomeration process, a low shear agglomeration process, a high pressure agglomeration process, a low pressure agglomeration process, a rotary drum agglomeration process, a pan agglomeration process, a roll press compaction process, a pin mixer process, a dry blending process, a spray coating process, an extrusion process, a pelletizing process and a fluid bed process.

1 . An absorbent particulate composition comprising:
 (a) an agglomerated mixture of one or more absorbent materials suitable for use in an animal litter; and   (b) powdered activated carbon having a particle size of about 50 to 700 microns;   wherein the composition is substantially free of any color-masking agents and wherein the composition has a color change of less than 30%, when the powered activated carbon is added to the absorbent materials.   
     
     
         2 . The absorbent particulate composition according to  claim 1 , wherein one or more of the absorbent materials is an absorbent clay selected from the group consisting of: bentonites, attapulgite, montmorillonite diatomaceous earth, Georgia White clay, sepiolite, slate, pumice, tobermite, marls, kaolinite, halloysite, smectite, hectorite, Fuller's earth and mixtures thereof. 
     
     
         3 . The absorbent particulate composition according to  claim 1 , wherein one or more of the absorbent materials is a cellulosic material made of plant products or by-products selected from the group consisting of: sawdust, waste-paper, wood, grains, hulls, nut shells, starches, fruit pulps, cotton, vegetables, nuts, trees, grasses, peat, and mixtures or combinations thereof. 
     
     
         4 . The absorbent particulate composition recited in  claim 1 , wherein said powdered activated carbon is present in 0.01-5 wt. % based on the weight of the particulate composition. 
     
     
         5 . The absorbent particulate composition recited in  claim 1 , wherein composition has a colorimetric rating of at least 60% white. 
     
     
         6 . The absorbent particulate composition recited in  claim 1 , wherein composition further comprises a binding agent for fixing the powdered activated carbon to one or more of the absorbent materials. 
     
     
         7 . The absorbent particulate composition recited in  claim 2 , wherein said particles of absorbent clay are about 5000 microns or less. 
     
     
         8 . The absorbent particulate composition recited in  claim 3 , wherein said particles of cellulosic materials are about 1500 microns or less. 
     
     
         9 . The absorbent particulate composition recited in  claim 1 , further comprising wherein an additive selected from the group consisting of antimicrobials, odor absorbers/inhibitors, binders, fragrances, litter filler materials, health indicating materials, nonstick release agents, superabsorbent materials, and mixtures thereof. 
     
     
         10 . The absorbent particulate composition recited in  claim 9 , wherein said antimicrobial active is selected from the group consisting of boron containing compounds such as borax pentahydrate, borax decahydrate, boric acid, polyborate, tetraboric acid, sodium metaborate anhydrous, boron components of polymers, and mixtures thereof. 
     
     
         11 . An absorbent particulate composition comprising:
 (a) extruded particles comprising a mixture of one or more absorbent materials suitable for use in an animal litter; and   (b) powdered activated carbon having a particle size of about 50 to 700 microns;   wherein the composition is substantially free of any color-masking agents and wherein composition has a colorimetric rating of at least 55% white.   
     
     
         12 . The absorbent particulate composition according to  claim 11 , wherein the powdered activated carbon is combined with one or more absorbent materials so that it integrated into the extruded particles. 
     
     
         13 . The absorbent particulate composition recited in  claim 11 , wherein composition further comprises a binding agent for coating one or more of the extruded particles with powdered activated carbon. 
     
     
         14 . The absorbent particulate composition according to  claim 11 , wherein the powdered activated carbon is one or more of the absorbent materials is absorbent clay selected from the group consisting of: bentonites, attapulgite, montmorillonite diatomaceous earth, Georgia White clay, sepiolite, slate, pumice, tobermite, marls, kaolinite, halloysite, smectite, hectorite, Fuller's earth and mixtures thereof. 
     
     
         15 . The absorbent particulate composition according to  claim 11 , wherein one or more of the absorbent materials is a cellulosic material made of plant products or by-products selected from the group consisting of: sawdust, waste-paper, wood, grains, hulls, nut shells, starches, fruit pulps, cotton, vegetables, nuts, trees, grasses, peat, and mixtures or combinations thereof. 
     
     
         16 . The absorbent particulate composition recited in  claim 11 , wherein said powdered activated carbon is present in 0.01-5 wt. % based on the weight of the particulate composition. 
     
     
         17 . The absorbent particulate composition recited in  claim 11 , wherein composition a color change of less than 20%, when the powered activated carbon is added to the absorbent materials. 
     
     
         18 . The absorbent particulate composition recited in  claim 11 , further comprising wherein an additive selected from the group consisting of antimicrobials, odor absorbers/inhibitors, binders, fragrances, litter filler materials, health indicating materials, nonstick release agents, superabsorbent materials, and mixtures thereof. 
     
     
         19 . An absorbent particulate composition comprising:
 (a) dry blended particles comprising a mixture of one or more absorbent materials suitable for use in an animal litter; and   (b) powdered activated carbon having a particle size of about 50 to 700 microns;   wherein the composition is substantially free of any color-masking agents.   
     
     
         20 . The absorbent particulate composition recited in  claim 19 , wherein composition further comprises a binding agent for coating one or more of the absorbent particles with powdered activated carbon.