The Effect of Natural Zeolite on Kitty Litter

Sodium bentonite clumping litters (BCL) are popular on the market because they clump cat waste, making it easy to remove and dispose. However, the purity of bentonite ranges from product to product, and a lower purity results in microbial activity and resultant odors (Hogg, 2012).

The odor absorption properties of zeolite are well documented and exceed those of bentonite (Hogg, 2012). Zeolites also absorb up to 50 percent of their weight in liquids without expansion, and individual wet grains bind into clumps. Because of these characteristics, zeolite is added to many bentonite and non-bentonite litters to provide additional odor and moisture control.


In 2012, KMI conducted a substantial research and product development program with its zeolite resulting in the creation of a new product, zeolite clumping litter (ZCL). The program compared the physical and chemical properties of zeolite and bentonite to measure and compare their performance (Hogg, 2012). In this trial, the relative odor of each clump was assessed using the ‘sniff’ test.
During the first two parts of the trial, a standard litter box (16” x 12”) was set up and each day, clumps were removed and measured for length, width, weight, smell, and strength (Hogg, 2012). The target number of clumps was 50 from each type of litter (ZCL and BCL). Following the completion of this phase, a third trial provided the choice of two litter boxes, one filled with ZCL, and the second with BCL. The litter boxes were placed side by side for one week. Again, all clumps were measured for length, width, weight, smell, and strength. Finally, the fourth phase of the trial provided a litter box containing a mixture of ZCL with BCL.
The results of the trial indicated that the odor control of zeolite was noticeably improved over bentonite; ZCL clumps did not have a detectible odor within 24 hours (Hogg, 2012). Also, the fugitive dust in the zeolite product was measurably less than that of the bentonite product (Hogg, 2012). When given a choice, the cat used in the trial also preferred ZCL over BCL; the box filled with ZCL was used at a much high frequency that the box filled with BCL (Hogg, 2012). In terms of handling waste, ZCL was 40 percent more effective than BCL (Hogg, 2012). On a pound per pound basis, ZCL also provided 20 percent more volume than BCL; the researcher determined that 8lb of zeolite litter is equivalent to 10lb of bentonite litter (Hogg, 2012). Due to the strength of zeolite clumps, they were also determined to be easier to handle and dispose of than bentonite clumps. Besides providing superior odor control and waste management, zeolite is also linked to several environmental rewards. For example, less weight and volume of zeolite are required to achieve superior results to bentonite litter (Hogg, 2012). This equates to less packing materials and less disposal of waste into the environment.