Odor-absorbing materials and processes for their preparation and use
A slightly puffed, low density, moisture-absorbing and odor-absorbing additive that can readily remove undesirable odors from a confined space is produced from re-purposed spent carbon materials obtained from other processes. The product is particularly suitable as an addition to animal litters and the like with possible uses in human applications. An aspect of the method includes a step of extruding a spent carbon mixture, optionally containing diatomaceous earth to obtain the additive. Also disclosed are de-germinated corn flour, or grits, that aid process flow and can serve as a substrate for the spent carbon materials.
1. An animal litter comprising a plurality of discrete particles of a sorbing material and particles of a puffed, odor-absorbing additive, said additive having been prepared by a method comprising:
(a) extruding a blend including spent carbon material and a matrix material under conditions sufficient to obtain an expanded extrudate comprising a puffed product; and
(b) drying said puffed product to obtain the additive, wherein said additive comprises an extrudate of spent carbon material and flour.
2. The animal litter according to claim 1 , wherein said animal litter has a sorption capacity of at least about 0.04 ml water per gram of litter.
3. An animal litter according to claim 1 , wherein said spent carbon material is recovered from a starch hydrolysis production process.
4. An animal litter according to claim 3 , wherein said spent carbon material is originated from constituents comprising diatomaceous earth and powdered or activated carbon.
5. An animal litter according to claim 1 , wherein said spent carbon material is recovered from a brewing production process.
6. An animal litter according to claim 1 , wherein said spent carbon material is recovered from a water treatment production process.