Composite Absorbent Particles

Abstract

Composite particles and methods for making the same. An absorbent material is formed into a particle. An optional performance-enhancing active is coupled to the absorbent material before, during, or after the particle-forming process, homogeneously and/or in layers. Additionally, the composite absorbent particle may include a core material. Preferred methods for creating the absorbent particles 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 mix muller process, a roll press compaction process, a pin mixer process, a batch tumble blending mixer process, an extrusion process, and a fluid bed process.

1 . A plurality of porous composite particles suitable for use as an animal litter formed by: the process comprising:
 agglomerating bentonite and powder activated carbon (PAC) into a plurality of bentonite-based porous composite particles suitable for use as an animal litter, wherein   the PAC is present in 0.1-1%,   at least a portion of the PAC is encapsulated within the pores of the composite particle, and   the agglomeration is accomplished using a pan agglomerator, a pin mixer or a Pelligrini mixer/Muller agglomerator.   
   
   
       2 . The plurality of porous composite particles formed by the process recited in  claim 1 , wherein the PAC is present in 0.5%. 
   
   
       3 . The plurality of porous composite particles formed by the process recited in  claim 1  having a malodor rating less than 15 as determined by the Malodor Sensory Method. 
   
   
       4 . The plurality of porous composite particles formed by the process recited in  claim 1  having a malodor rating between 10 and 15 as determined by the Malodor Sensory Method. 
   
   
       5 . The plurality of porous composite particles formed by the process recited in  claim 1  having a hydraulic conductivity value of 0.25 cm/s or less. 
   
   
       6 . The plurality of porous composite particles formed by the process recited in  claim 1 , wherein the composite particles have a dusting attrition value of at most about 15% as measured by ASTM method E-728 Standard Test Method for Resistance to Attrition of Granular Carriers and Granular Pesticides. 
   
   
       7 . The plurality of porous composite particles formed by the process recited in  claim 1 , wherein the clump strength, an indication of the percentage of particles retained in a clump after six hours upon addition of animal urine, is greater than 90%. 
   
   
       8 . The plurality of porous composite particles formed by the process recited in  claim 1  wherein the bentonite is sodium bentonite. 
   
   
       9 . The plurality of porous composite particles formed by the process recited in  claim 1  wherein the bentonite has a mean particle diameter of about 25-150 μm. 
   
   
       10 . An improved animal litter comprising:
 an absorbent material suitable for use as an animal litter; and   a plurality of porous composite particles formed by the process recited in  claim 1 .   
   
   
       11 . The improved animal litter recited in  claim 10  having a malodor rating less than 15 as determined by the Malodor Sensory Method. 
   
   
       12 . The improved animal litter recited in  claim 10  having a malodor rating between 10 and 15 as determined by the Malodor Sensory Method. 
   
   
       13 . The improved animal litter recited in  claim 10  having a hydraulic conductivity value of 0.25 cm/s or less. 
   
   
       14 . The improved animal litter recited in  claim 10 , wherein the animal litter has a dusting attrition value of at most about 15% as measured by ASTM method E-728 Standard Test Method for Resistance to Attrition of Granular Carriers and Granular Pesticides. 
   
   
       15 . The improved animal litter recited in  claim 10  having a clump strength greater than 95%. 
   
   
       16 . The improved animal litter recited in  claim 10 , wherein the clump strength, an indication of the percentage of particles retained in a clump after six hours upon addition of animal urine, is greater than 90%. 
   
   
       17 . The improved animal litter recited in  claim 10  having a Multiple Cat Usage Index of at least 8. 
   
   
       18 . The improved animal litter recited in  claim 10  wherein the bentonite is sodium bentonite. 
   
   
       19 . The improved animal litter recited in  claim 10  wherein the bentonite has a mean particle diameter of about 25-150 μm. 
   
   
       20 . The improved animal litter recited in  claim 10  wherein the absorbent material suitable for use as an animal litter is bentonite.