A particulate clumping animal litter composition is disclosed. The composition comprises water-swellable smectite clay particles bound to magnetically-attractable metal particles such that substantially all particles of the animal litter composition are attracted to a magnetic surface. The animal litter composition exhibits favorable properties such as absorbency, resiliency, homogeneity, clump strength, and particle size. Methods of production for clumping animal litter compositions are also disclosed that employ sufficient shear to bind the water-swellable smectite clay particles to the magnetically-attractable metal particles such that the animal litter compositions exhibit favorable properties. A method and apparatus for the collection of magnetically-attractable animal litter particles are also disclosed.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates a perspective view of a magnetic sweeper in accordance with the present disclosure.
FIG. 2 illustrates a perspective view of a hand-held electromagnetic collector in accordance with the present disclosure.
Claims
1-47. (canceled)
48. A method for the collection of magnetically-attractable clumping animal litter, comprising the step of brushing a collection device over an area contaminated with individual magnetically-attractable clumping animal litter particles, the collection device comprising a magnetic plate, a stem, and a handle.
49. The method of claim 48, the collection device further comprising a source of electrical energy, wherein the magnetic plate is an electromagnet.
50. The method of claim 49, further including the step of switching off the electrical energy to the electromagnet, after collecting magnetic litter on the magnetic plate, to remove the collected magnetic particles from the magnetic plate.
51. The method of claim 48, wherein the magnetically-attractable animal litter composition comprises:
(a) about 50 to 98 weight % of a water-swellable smectite clay; and,(b) about 2 to 50 weight % of magnetically-attractable metal particles;wherein:
(i) the water-swellable smectite clay and magnetically-attractable metal particles are bound together;(ii) substantially all particles of the animal litter composition are attracted to a magnetic surface; and,(iii) the resiliency of the animal litter composition is at least about 50%, wherein the resiliency is determined by measuring the weight fraction of animal litter particles initially larger than 40 mesh that are retained on a 40-mesh sieve after being fragmented by swirling at a rate of about 280 rpm and tapping at a frequency of about 150 min−1 for 5 minutes in the pan of a rotary test sieve shaker containing ten ⅝″-diameter ball bearings.
52. The method of claim 51, wherein the resiliency of the animal litter composition is at least about 75%.
53. The method of claim 52, wherein the resiliency of the animal litter composition is about 75 to 98%.
54. The method of claim 51, comprising about 80 to 97 weight % of a water-swellable smectite clay and 3 to 20 weight % of magnetically-attractable metal particles.
55. The method of claim 48, wherein the water-swellable smectite clay comprises a mixed-ion bentonite clay.
56. The method of claim 48, wherein the water-swellable smectite clay comprises at least about 20% exchangeable sodium relative to all interlayer exchangeable cations.
57. The method of claim 56, wherein the water-swellable smectite clay comprises at about 20-50% exchangeable sodium relative to all interlayer exchangeable cations.
58. The method of claim 57, wherein the water-swellable smectite clay comprises at about 20-40% exchangeable sodium relative to all interlayer exchangeable cations.
59. The method of claim 48, wherein the water-swellable smectite clay has a particle size distribution such that at least 25 weight % of the particles pass a 50-mesh sieve.
60. The method of claim 48, wherein the magnetically-attractable metal particles comprise iron, nickel, cobalt, or mixtures thereof.
61. The method of claim 48, wherein the magnetically-attractable metal particles have a particle size distribution such that at least 25 weight % of the particles pass a 50-mesh sieve.
62. The method of claim 48, wherein the magnetically-attractable metal particles comprise magnetite, taconite, or mixtures thereof.
63. The method of claim 48, wherein the magnetically-attractable metal particles comprise taconite having an iron content of at least 25 weight %.
64. The method of claim 48, wherein the particles of the animal litter composition have particle sizes between 8 and 50 mesh.
65. The method of claim 64, wherein the particles of the animal litter composition have particle sizes between 10 and 40 mesh.
66. The method of claim 48, wherein the magnetically-attractable animal litter composition comprises:
(a) about 50 to 98 weight % of a water-swellable smectite clay; and,(b) about 2 to 50 weight % of magnetically-attractable metal particles;wherein:
(i) the water-swellable smectite clay and magnetically-attractable metal particles are bound together;(ii) substantially all particles of the animal litter composition are attracted to a magnetic surface; and,(iii) the clump strength at a clump time of 1 hour of the animal litter composition is at least about 0.9 lb, wherein the clump strength at a clump time of 1 hour is determined by measuring the compressive force required to break an animal litter clump formed by adding 10 ml of 2 weight % aqueous sodium chloride to a sample of the dry animal litter and allowing the clump to form for 1 hour.
67. The method of claim 66, wherein the clump strength at a clump time of 1 hour of the animal litter composition is about 1.5 to 8 lb, wherein the clump strength at a clump time of 1 hour is determined by measuring the compressive force required to break an animal litter clump formed by adding 10 ml of 2 weight % aqueous sodium chloride to a sample of the dry animal litter and allowing the clump to form for 1 hour.
68. The method of claim 66, wherein the clump strength at a clump time of 24 hours of the animal litter composition is about 3 to 40 lb, wherein the clump strength at a clump time of 24 hours is determined by measuring the compressive force required to break an animal litter clump formed by adding 10 ml of 2 weight % aqueous sodium chloride to a sample of the dry animal litter and allowing the clump to form for 24 hours.
69. The method of claim 68, wherein the clump strength at a clump time of 24 hours of the animal litter composition is about 4 to 30 lb, wherein the clump strength at a clump time of 24 hours is determined by measuring the compressive force required to break an animal litter clump formed by adding 10 ml of 2 weight % aqueous sodium chloride to a sample of the dry animal litter and allowing the clump to form for 24 hours.
70. The method of claim 48, wherein the magnetically-attractable animal litter composition comprises:
(a) about 50 to 98 weight % of a water-swellable smectite clay; and,(b) about 2 to 50 weight % of magnetically-attractable metal particles;wherein:
(i) the water-swellable smectite clay and magnetically-attractable metal particles are bound together;(ii) substantially all particles of the animal litter composition are attracted to a magnetic surface; and,(iii) the clump strength at a clump time of 1 hour of the animal litter composition is at least about 1 psi, wherein the clump strength at a clump time of 1 hour is determined by measuring the compressive force required to break an animal litter clump formed by adding 10 ml of 2 weight % aqueous sodium chloride to a sample of the dry animal litter and allowing the clump to form for 1 hour.
71. The method of claim 70, wherein the clump strength at a clump time of 1 hour of the animal litter composition is about 1.5 to 10 psi, wherein the clump strength at a clump time of 1 hour is determined by measuring the compressive force required to break an animal litter clump formed by adding 10 ml of 2 weight % aqueous sodium chloride to a sample of the dry animal litter and allowing the clump to form for 1 hour.
72. The method of claim 70, wherein the clump strength at a clump time of 24 hours of the animal litter composition is about 3 to 50 psi, wherein the clump strength at a clump time of 24 hours is determined by measuring the compressive force required to break an animal litter clump formed by adding 10 ml of 2 weight % aqueous sodium chloride to a sample of the dry animal litter and allowing the clump to form for 24 hours.
73. The method of claim 72, wherein the clump strength at a clump time of 24 hours of the animal litter composition is about 4 to 40 psi, wherein the clump strength at a clump time of 24 hours is determined by measuring the compressive force required to break an animal litter clump formed by adding 10 ml of 2 weight % aqueous sodium chloride to a sample of the dry animal litter and allowing the clump to form for 24 hours.
74. The method of claim 48, wherein the magnetically-attractable animal litter composition comprises:
(a) about 50 to 98 weight % of a water-swellable smectite clay; and,(b) about 2 to 50 weight % of magnetically-attractable metal particles;wherein:
(i) the water-swellable smectite clay and magnetically-attractable metal particles are bound together; and,(ii) the inhomogeneity of the animal litter composition is not more than about 30%, wherein the inhomogeneity is determined by measuring the reduction in weight fraction of animal litter particles adhering to a vertical magnetic surface after being crushed such that the D50 of the animal litter particles after crushing is at least about ⅓ less than the D50 of the animal litter particles before crushing.
75. The method of claim 74, wherein the inhomogeneity of the animal litter composition is not more than about 20%.
76. The method of claim 75, wherein the inhomogeneity of the animal litter composition is not more than about 10%.
77. The method of claim 48, wherein the magnetically-attractable animal litter composition comprises:
(a) about 85 to 95 weight % of bentonite clay particles having a particle size distribution such that at least 50 weight % of the particles pass a 50-mesh sieve, the bentonite clay particles comprising at least about 20% exchangeable sodium relative to all interlayer exchangeable cations; and,(b) about 5 to 15 weight % of magnetically-attractable metal particles having a particle size distribution such that at least 50 weight % of the particles pass a 50-mesh sieve, the magnetically-attractable metal particles comprising magnetite, taconite, or mixtures thereof;wherein:
(i) the bentonite particles and magnetically-attractable metal particles are bound together;(ii) the particles of the animal litter composition have particle sizes between 8 and 50 mesh;(iii) substantially all particles of the animal litter composition are attracted to a magnetic surface; and,(iv) the resiliency of the animal litter composition is at least about 50%, the resiliency being determined by measuring the weight fraction of animal litter particles initially larger than 40 mesh that are retained on a 40-mesh sieve after being fragmented by swirling at a rate of about 280 rpm and tapping at a frequency of about 150 min−1 for 5 minutes in the pan of a rotary test sieve shaker containing ten ⅝″-diameter ball bearings.
78. The method of claim 77, wherein:
(i) the clump strength a clump time of 24 hours of the animal litter composition is about 3 to 40 lb, wherein the clump strength a clump time of 24 hours is determined by measuring the compressive force required to break an animal litter clump formed by adding 10 ml of 2 weight % aqueous sodium chloride to a sample of the dry animal litter and allowing the clump to form for 24 hours; and,
(ii) the clump strength a clump time of 1 hour of the animal litter composition is about 0.9 to 10 lb, wherein the clump strength a clump time of 1 hour is determined by measuring the compressive force required to break an animal litter clump formed by adding 10 ml of 2 weight % aqueous sodium chloride to a sample of the dry animal litter and allowing the clump to form for 1 hour.
Patent Application
20070169710
