Patent Application
20070254809
This invention relates to compositions serving as a carrier for controlled release of pesticides and a pesticide product including both the carrier and a pesticide. The controlled release includes a quick release that results in a lethal or significantly inhibiting application of the pesticide to the deleterious organism.
More particularly, the pesticide product comprises the carrier and a pesticide applied to the surface of the carrier or mixed with the release material of the carrier.
Accordingly, the present new pesticide carrier and product have been developed to control organisms that are deleterious to plants such as employed for agriculture, horticulture, lawns and gardens, and any other situation where control of such organisms is desired.
The present invention includes a pesticide carrier composition comprising a core particle that is absorbent and a coated or absorbed pesticide release material. The core particles may further be coated with a filler/release control agent.
The present invention further includes a pesticide product comprising the aforesaid carrier composition and a pesticide applied to the surface of the carrier composition or mixed with the pesticide release material of the carrier.
The pesticide release material is water soluble so that when the pesticide product is applied to plants or soil, natural precipitation or irrigation water will solubilize the pesticide release material, providing for a controlled quick release of the pesticide over coating or pesticide release material mixture, and thus deliver a lethal or significantly inhibiting application of the pesticide to one of more types of deleterious organisms. The quick delivery of the pesticide has the effect of reducing the total amount of pesticide to be effective, thus reducing costs and reducing the environmental impact.
The present pesticide carrier composition comprises:
(1) a core particle having (a) absorbent voids and pores at least on the surface, or (b) having a rough, absorbent surface, and
(2) a pesticide release material that is water soluble and is on the surface or absorbed within the surface of the core particle.
The core particle may be composed of granulated agglomerated smaller particles. The core particles may further be coated with a filler/release control agent (mixed or not mixed with the pesticide release material) to control the density of the core particle and solubility of the pesticide release material.
The pesticide product comprises (1) the carrier composition and (2) a pesticide or pesticide composition applied to the surface of the carrier composition and/or mixed with the pesticide release material of the carrier. Pesticides include herbicides, insecticides, fungicides and any other substance for controlling living organisms that are deleterious to plants.
The pesticide release material is water soluble so that when the pesticide product is applied to plants, insects, soil and other locations of deleterious organisms, then natural precipitation or irrigation water will solubilize the pesticide release material, providing for a controlled quick release of the pesticide over coating or pesticide release material mixture, and thus deliver a lethal or significantly inhibiting application of the pesticide to one or more types of deleterious organisms.
The preferred density of the pesticide product is a weight density of from 15 to 65 lb/ft3 and a more preferred weight density of 20 to 40 lb/ft3 and a most preferred weight density of 20 to 30 lb/ft3. The pesticide product has a preferable size of 0.20 mm to 25 mm and a more preferable size of 1 mm to 4 mm and a most preferable size of 1 mm to 2 mm.
Core particles containing pores or voids have voids at the surface, such that the voids at the surface are between 10-200 microns in cross-sectional diameter, with the surface being coated in an amount preferably of 40-100%, more preferably 75-100% and most preferably 90-100% of the voids with the pesticide release material. The core particles include one of more of the following materials: perlite, shredded newspaper, saw dusts, cedar fines, spruce fines, hardwood fines, limestone, zeolite, peat moss, peanut hulls, calcium carbonate, wood chips including pine chips and fines, attapulgite clay (atta clay), bentonite, vermiculite, cotton lint, ground corn cobs, corn cob flower, Metrecz absorbent and diatomaceous earth.
Release materials are water soluble and includes one or more of the following: ammonium sulfate, urea, di-ammonium phosphate, potassium chloride, calcium nitrate, potassium sulfate, zinc sulfate, aluminum sulfate, magnesium sulfate, manganese sulfate, sodium nitrate, potassium nitrate, copper sulfate, boric acid, borax (e.g., 5 mole borax), mono ammonium phosphate, calcium phosphate, and single and triple super phosphate. Other water soluble release materials are encompassed within the scope of this invention, particularly those conferring a growth benefit to plants such as a nutrient benefit.
The filler/release control agent includes the following: plant starches, protein gels, glues, gumming compositions, crystallizing compounds, gelling clays, and synthetic gel forming compounds; and other plant starches, protein gels and glues, gumming products, crystallizing compounds, gelling clays, and synthetic gel forming compounds also work as the filler/release control agent. These include but are not limited to the following: corn starch, rice starch, potato starch, wheat starch, tapioca starch, and any starch which contains the D-glucopyranose polymers, amylose and amylopectin; modified starch of the former listing (also including corn starch) by acetylation, ethylation, chlorination, acid hydrolysis, or enzymatic action which yield starch acetates, esters, and ethers; starch phosphate, an ester made from the reaction of a mixture of orthophosphate salts (sodium dihydrogen phosphate and disodium hydrogen phosphate) with any of the listed (also including corn starch) starch/or starches; gelatin as made by hydrolysis of collagen by treating raw materials with acid or alkali; glue as made from any of the following: collagen, casein, blood, and vegetable protein such as that of soybeans; gumming products such as cellulosics, rubber latex, gums, terpene resins, mucilages, asphalts, pitches, hydrocarbon resins; crystallizing compounds such as sodium silicate, phosphate cements, calcium-oxide cements, hydraulic cements (mortar, gypsum); gelling clays in the form of very fine powders; synthetic gel forming compounds such as polysulfide sealants, polyethylene, isobutylene, polyamides, polyvinyl acetate, epoxy, phenolformaldehyde, urea formaldehyde, polyvinyl butyral, cyanoacrylates, and silicone cements. Plant starches work particularly well, especially corn and wheat starches.
The pesticide of the present pesticide product includes one or more insecticides such as 0,0-diethyl O-(2-isopropyl-6 methyl-4 pyrimidinyl) phosphorothioate, one or more herbicides such as 2,4-dichlorophenoxyacetic acid, one or more fungicides such as ferric-di-methyl-dithiocarbamate or combination of one or more insecticides, herbicides and fungicides. Further examples of pesticides and organism control substances (including selective growth regulators) are 2-(2-Methyl-4-chlorophenoxy)propionic acid; 2-Methyl-4-chlorophenoxyacetic acid; 3,6-Dichloro-o-anisic acid; Pyrethrins; 2-chloro-4-ethylamino-s-triazine; Benefin: N-butyl-N-ethyl-alpha, alpha, alpha, trifluoro-2,6-dinitro-p-toluidine; Trifluralin: alpha, alpha, alpha, trifluoro-2, trifluoro-2,6-dinitro-N,N-dipropyl-p-toluidine; Dithiopyr 3,5-pyridenedicarbothiocic acid, 2-(difluoromethyl)-4-(2-methylpropyl)-6-(trifluoromethyl)-S, S-dimethyl ester; Chlorpyrifos(O,O-diethyl-O-(3,5,6-trichloro-2-pyridyl)phosphorothioate; O,O-Diethyl S-(2-(ethylthio)ethyl)phosphorodithioate; (2,2,2-trichloro-1-hydroxethyl)phosphonate; 1-((6-chloro-3-pyridinyl)methyl)-N-nitro-2-imidazolidinimine; Cyano(4-fluoro-3-phenoxyphenyl)methyl 3-(2,2-dichloroethenyl)-2,2-dimethylcyclopropane carboxylate; (2,4,6,8-tetramethyl-1,3,5,7-tetraoxycyclo-octane); Prodiamine, (N3, N3-Di-n-propyl-2,4-nitro-6(trifluoromethyl)-m-phenylenediamine)
A further embodiment of the present pesticide product includes the addition of one or more fertilizer compounds to the release material, previously absorbed by the carrier or provided as one or more additional coatings. The fertilizer compounds include nitrogen compounds, phosphorous compounds and potassium compounds. The nitrogen compounds include urea, ammonia, ammonium nitrate, ammonium sulfate, calcium nitrate, diammonium phosphate, monoammonium phosphate, potassium nitrate and sodium nitrate. The phosphorous compounds include diammonium phosphate, monoammonium phosphate, calcium phosphate, monopotassium phosphate, dipotassium phosphate, tetrapotassium pyrophosphate, and potassium metaphosphate. The potassium compound includes potassium chloride, potassium nitrate, potassium sulfate, monopotassium phosphate, dipotassium phosphate, tetrapotassium pyrophosphate, and potassium metaphosphate.
Similarly, additional nutrients may be added. These include all secondary nutrients (for example, sulfur, calcium, and magnesium) and all micronutrients (for example boron, copper, iron, manganese, molybdenum, zinc), as well as growth regulators such as, but not limited to, potassium azide, 2 amino-4-chloro-6-methylpyrimidine, N-(3,5-dichlorophenyl)succinimide, 3-amino-1,2,4 triazole and nitrification regulators such as, but not limited to, 2-chloro-6-(trichloromethyl)pyridine, sulfathiazole, dicyandiamide, thiourea, and guanylthiourea.
A full combined nitrogen-phosphorus-potassium (NPK) fertilizer can be made by using compounds of nitrogen, phosphorus and potassium to provide proportions of N-P-K, for example, of 29-3-4, 16-4-8, 10-10-10, 15-5-10, 15-0-15, 22-3-14, 20-28-5, 35-3-9, 38-3-4 and 12-6-6. In particular, NPK fertilizer may contain nitrogen from urea, nitrogen and phosphorus from monoammonium phosphate and/or diammonium phosphate, and potassium from potassium chloride in various proportions and concentrations, and then blending the product with a filler to provide proportions of NPK for example, of 29-3-4, 16-4-8, 10-10-10, 15-5-10, 15-0-15, 22-3-14, 20-28-5, 35-3-9, 38-3-4 and 12-6-6.
The carrier composition of the present invention is produced by two types of granulation methods. The first method includes combining a slurry of pesticide release material and water with small core particles and granulating the mixture to form larger agglomerated particles which are the carrier.
The second method includes overcoating large core particles with a slurry of pesticide release material and water, using a granulation method. The filler/release control agent may be mixed with the pesticide release material. A particularly useful filler/release control agent has the additional benefit of being a granulation aid.
While a pesticide product may be desired having a low density, it often desirable to have a much more difficult to attain, high density product. The high density product is a concentrated product, having improved handling characteristics and the possibility of additionally controlled pesticide release properties
The present invention includes a higher density product.
To produce such a higher bulk density product, core particles of highly absorbent material is employed to thus absorb a high amount of release material which may or may not include a filler/release control agent.
To produce the highest density product, the present invention includes the process embodiment of, for example, the steps of 1) introducing water to core particles of absorbent material (i.e., absorbent particles) to result in absorption of water within the absorbent material, 2) heating the absorbent particles and water to transform the water within the absorbent particles to steam and thus expand the core particles, 3) introducing the heated absorbent, core particles to a release material which may or may not include a filler/release control agent, 4) granulating the foregoing to solidify and harden the mixture, resulting in the agglomeration of absorbent core particles into carrier granules, and 5) drying the carrier granules.
Perlite, usually available and used in an expanded (i.e., “popped”) form, is highly absorbent and may be employed as the material of the core particles to produce the higher density, concentrated product.
To produce the highest density, concentrated product using perlite, important process features of the present invention are employed, including the following: 1) expanded (“popped”) perlite is further steam exfoliated beyond its normal popped form to allow better penetration and filling of its interspatial regions by the release material either mixed or not mixed with filler/release control agent (the amount of steam exfoliation is controlled to regulate the size of interspatial regions and thus the density of the product); 2) solutions and slurries of the foregoing are maintained around 30 to 98% concentration, preferably 50 to 99% concentration and most preferably 62 to 99%, to minimize voids formed from evaporation during the processing (For particular carrier core particles, lesser concentrations may be employed to control the density of the product, such as for example, when using ammonium sulfate solutions, the solution is preferably 60-70% concentration and more preferably 62 to 67% concentration); and 3) the small perlite particles containing release material with or without filler/release control agent, are granulated together to form dense, particles.
Exfoliated and/or expanded (popped) perlites product particularly good pesticide carrier compositions and pesticide products. The inside microstructure of an exfoliated and/or expanded perlite particle is comparable to a honeycomb type arrangement; the individual cells indicate diameters of 10 to 200 microns, with a preferred range being 25 to 150 microns, and the most preferred range being 40 to 100 microns. As such, the exfoliated and/or expanded perlite used can have a loose weight density of from 2 to 20 lb/ft3 with a preferred range of 2 to 10 lb/ft3 and a most preferred range of 2 to 6 lb/ft3.
The pesticide may be mixed in with the release material or coated on the carrier. The pesticide may be mixed in or coated using the following exemplary equipment: drum coater, pan coater, fluid-bed coater, pugmill mixer, homogenizer, industry recognized mixers such as pin mixers and screw feeders, and other industry recognized coating apparatuses.
The pesticide may be applied to the carrier particles by any of the following exemplary methods:
1. Apply liquid pesticide with a spray nozzle
a. Air atomizing nozzle
b. Hydraulic nozzle
c. Others
2. Apply waxy pesticide material with a heated spray nozzle
a. Air atomizing nozzle
b. Hydraulic nozzle
c. Others
3. Apply a sticking agent to carrier and apply over-coating of pesticide in powder form
4. Apply pesticides during the granulation of carrier
5. Apply pesticides in other industry recognized methods
Pesticides may be applied in the following exemplary forms:
When the pesticide is applied in a powder form, a sticking agent may be applied to the surface of the carrier. Examples of sticking agents include one or more of the following: di-propylene glycol (DPG), soybean oil, starch, sugar solution.
The following examples/tests show how the present invention has taken the above concepts and developed them into a unique pesticide carrier and method of making and using same.
While ammonium sulfate has been employed as the release material in specific amounts in granulation Examples 1-4, the release material may in general be mixed in with the core particles in an amount preferably 1-30 wt % concentration, more preferably 2-20 wt %, and most preferably 4-11 wt %.
Additionally, in the following examples/tests, the following information is provided to better describe employed materials:
Additionally, the N-P-K (15-15-15) employed in the tests is produced by Norsk Hydro ASA c/o Hydro Agri North America, Inc. The ingredients are ammonium nitrate, calcium phosphate, monoammonium phosphate (MAP), diammonium phosphate (DAP), potassium sulfate.
Permethrin is ((3-phenoxyphenyl)methyl-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropanecarboxylate).
TRIMEC™ is manufactured by PBI/GORDON Corporation, sold under the retail name of Weedout™ and is composed of dimethylamine salt of 2-(2-methyl-4-chlorophenoxy)propionic acid, dimethylamine of 2,4-dichlorophenoxyacetic acid, dimethylamine salt of dicamba (3,6-dichloro-O-anisic acid).
The following types of perlite were employed:
1. “perlite 3-S” having a median particle size of 0.36 mm by weight and bulk density of 3 lb/cubic ft;
2. “perlite #5” having a median particle size of 2.42 mm by weight and bulk density of 6.5 lb/cubic ft; and
3. “perlite #1” having a median particle size of 1.3 mm by weight and bulk density of 8 lb./cubic ft.
In tests where results of hardness and abrasion resistance are provided, these measurements were determined by the following methods:
Tennessee Valley Authority (TVA) (1) Crushing Test for hardness and TVA (2) Abrasion Resistance Test for abrasion resistance, as published in “Physical Properties of Fertilizers and Methods for Measuring Them”, Bulletin Y-147, October 1979, published by National Fertilizer Development Center, TVA, Muscle Shoals, Alabama.
Thus, the invention is demonstrated with reference to the following examples/tests, which are of an illustrative nature only and which are to be construed as non-limiting. See Table 1 for test results.
200 g De-ionized water
400 g AmSO4 fines (67%)
50 g Perlite #5 (11.1%)
200 g De-ionized water
400 g AmSO4 fines (67%)
26 g Perlite 3-S (6.1%)
Process
200 g De-ionized water
550 g AmSO4 (73.3%)
12.3 g Corn starch B810 (2%)
50 g Perlite #5 (8.2%)
Process
200 g De-ionized water
550 g AmSO4 (73.3%)
12.3 g Corn starch B810 (2%)
50 g Perlite 3-S (4/3%)
Process
200 g De-ionized water
400 g AmSO4 (67%)
9.2 g Wheat starch Midsol 50 (2%)
50 g Perlite #5 (10.9%)
Process
All pesticides were Permethrin
All products coated to 0.5% pesticide
Conditions of Tests A-D
Test A:
1.36 g Pesticide
98.6 g Batch (using the preceding described Test 29)
5 psi spray pressure
Test B:
1.36 g Pesticide
98.6 g Batch (using the preceding described Test 17)
5 psi spray pressure
Test C,
1.36 g Pesticide
98.6 g Batch (using the preceding described Test 24)
5 psi spray pressure
Test D:
1.36 g Pesticide
98.6 g Batch (using the preceding described Test 30)
5 psi spray pressure
The pesticide was sprayed using a peristaltic pump and air pressure using a 2850 air-atomizing nozzle. The material was coated in a drum to 0.5% pesticide.
All resulted in a good pesticide product.
Comments Regarding Performance of Tests and Test Results
All of Tests 1-9 employed ammonium sulfate because of its good solubility and pH which is neutral to most pesticides. Tests 1-9 were performed without granulation of the final mixture. All of Tests 1-9 included the addition of ammonium sulfate to 200° F. water while stirring to achieve a good mixture of AmSO4 and water. Tests 1-9 enabled the determination of solution concentrations of ammonium sulfate and water that could be handled on a practical basis. Tests were conducted at 50, 60, 67, and 73 percent concentrations of ammonium sulfate in water.
Tests 5 and 6 provided for determining the mixtures which could be used with added corn starch at 1% of solids which was homogenized into the ammonium sulfate solution/slurry at both 67 and 73%. The results were successful in both cases.
In Tests 8 and 9, perlite was successfully mixed into the solution/slurry of corn starch, ammonium sulfate, and H2O, at ammonium sulfate concentrations of both 67 and 73%.
Test 7 was performed to determine if use of large industrial grade crystals of ammonium sulfate could be used without grinding the large crystals. This did not work very well because they settled out of the slurry. Later tests employing ground (milled) crystals were successful. See tests 43 through 46.
Based on the results of Tests 1-9, additional tests were performed to see, if in particularly, ammonium sulfate could be incorporated with or without starch onto perlite while granulating the combination in a manner such that a pesticide incorporated and granulated with it or later sprayed on the outside surface of the resulting granules would be quickly available (released). Note that cedar fines contain a natural pesticide.
Two types of granulation were examined:
The tests determined ranges of successful embodiments of the present invention, for example using concentrations of corn starch of 1, 1.6, and 2% and perlite concentrations of approximately 4, 6, 8.2, 9.2, and 11%. Ammonium sulfate concentrations of 62, 67, and 73% were used. Perlite size was also varied to include 3 grades with particles of median size by weight of 0.36 mm, 1.3 mm, and 2.4 mm. All of the tests showed good success; however, the presence of recycled product in the granulation drum from previous granulation tests were found particularly desirable for good granulation. Excellent results occurred when the perlite was pre-heated and placed in a rolling bed and the solution/slurry poured over it. As shown in Test 17, conditions for excellent granules were 11% perlite, 67% ammonium sulfate concentration, both 1.3 mm and 2.4 mm sized perlite and 2% corn starch. However, even without starch, the tests were successful, as shown in Test 19. Wheat starch was found to be a good substitute for corn starch, as shown in Tests 23, 25, 26, and 27.
Additional tests were performed to verify the success of other embodiments of the present invention, using other absorbent materials, including finely ground yellow pine chips (Test 25), milled newspaper (test 26), and ground corn cobs (Test 27). All were successful when granulated in the same manner as, for example in Test 17. The milled newspaper yielded a very good product, because less weight (of the newspaper) was required to obtain a fairly low density (32 lb/ft3) product.
Test 28 repeated Test 17, but employed 1% corn starch instead of 2% corn starch. This resulted in a little higher bulk density product, 28.6 lb/ft3 (Test 28) instead of 26.3 lb/ft3 (Test 17). Test 29 employed smaller perlite particles (1.3 mm) instead of perlite particles of 2.4 mm and resulted in a granule bulk density of 30.3 lb/ft3.
In Test 30, corn starch was employed in an amount of 1.6%; perlite content was 6%; and ammonium sulfate solution/slurry was 62%. The perlite was mixed into the solution/slurry prior to granulation, similar to Test 15, but yielding a lower bulk density product because of using the 62% ammonium sulfate solution/slurry.
Because all of the products granulated well, tests were performed to determine how the products would act as a pesticide carrier. See Tests A, B, C and D. Thus, 0.5% of Permethrin was sprayed on the particles in a rotating drum. The pesticide was sprayed using a peristaltic pump and pneumatically atomized using a Spraying Systems 2850 air atomizing nozzle with 5 psi air pressure. The materials sprayed and coated were those made in Tests 17, 24, 29, and 30. Thus, each test used 1.36 g of diluted pesticide, which was sprayed on 98.6 g of carrier. The pesticide applied well and the resulting granules were free flowing and demonstrated good physical handling characteristics, with no problems such as caking or granule deterioration.
Other carrier compositions were tested using the primary ingredients of urea (see Tests 31, 32, 33, 34); NPK (15-15-15), (see Tests 35, 36, 37, 38); diammonium phosphate (see Tests 39, 40, 41, 42); and milled industrial grade ammonium sulfate (see Tests 43, 44, 45, 46). In addition, cedar fines were tested as core particles of the carrier which contains a natural pesticide (see Tests 33, 37, 41, and 45). Attapolgite clay was employed in Tests 34, 38, 42, and 46. All resulted in good product.
Other tests were conducted to determine the feasibility of using diammonium phosphate (see Test 47), cedar fines with 73% ammonium sulfate (see Test 48), and a combination of gypsum and KCl, with a 50% solution concentration (see Tests 49, 50, 51). CaNO3.5H2O was melted and mixed with perlite and then poured onto a rolling bed to successfully make granular material suitable for a carrier (see Test 52).
In test 53, perlite, at 5%, was pre-steamed and stirred into a homogenous mixture of 1% corn starch, 95% urea solution, and a green dye. The mixture was granulated in a rotary drum.
In tests 54 through 57, the feasibility of using ammonium sulfate (CO-60, Honeywell) obtained as a by-product of caprolactam production was determined. No granulation difficulties were encountered using the premix of perlite method of granulation either by the inherent impurities of this ammonium sulfate or the proprietary anti-caking agent used by the manufacturer of the ammonium sulfate. Granulation of the material using this ammonium sulfate was considered equal or better to pure or industrial grade ammonium sulfate.
In test 58, caprolactam by-product ammonium sulfate (CO-60, Honeywell) was used with only 0.5% corn starch and 11% perlite stirred into the mixture before it was granulated in a rolling bed in a drum. Again granulation was good, as was the case in Test 59, when ethylated corn starch (K-500) was used at 2% by weight of the carrier product instead of the previously used modified corn starch. Once again in Test 59, the ammonium sulfate was a caprolactam by-product
Several herbicide and insecticide carrier materials were produced utilizing two methods of drum granulation techniques. The first granulation technique performed during these tests is referred to as the pre-mix and drum granulation method. In Tests 60 and 61 ammonium sulfate carrier granules were produced by the following procedure.
Test #60
Approximately 200 grams of de-ionized water was heated to 200° F. Finely ground ammonium sulfate crystals was added (400 grams) to the water to produces a 67% solution/slurry. Corn starch (B810) was added (4.6 grams) (1% by weight) to the ammonium sulfate solution/slurry and homogenized to produce a homogenous mixture.
Approximately 2% active agent herbicide was added to the ammonium sulfate and corn starch solution/slurry to perform Test 60. The herbicide contained TRIMEC. TRIMEC is composed of dimethylamine salt of 2-(2-methyl-4-chlorophenoxy)propionic acid, dimethylamine of 2,4-dichlorophenoxyacetic acid, dimethylamine salt of dicamba (3,6-dichloro-O-anisic acid). The herbicide was added to the slurry and stirred. Perlite 3-S was incorporated into the solution slurry of ammonium sulfate, water, cornstarch, and herbicide and stirred to produce a homogenous mixture. The mixture was poured into a drum granulator to promote granulation of the material. Hot air was blown into the granulation drum to remove the moisture of the mixture until the particles were free flowing and granules were formed. The granules were removed from the granulation drum and placed in a lab oven at 125° F. for further drying.
Test #61
Approximately 200 grams of de-ionized water was heated to 200° F. Finely ground ammonium sulfate crystals was added (400 grams) to the water to produces a 67% solution/slurry. Corn starch (B810) was added (4.6 grams) (1% by weight) to the ammonium sulfate solution/slurry and homogenized to produce a homogenous mixture.
Approximately 2% active agent insecticide was added to the ammonium sulfate and corn starch solution/slurry to perform Test 61. The insecticide was Permethrin ((3-phenoxyphenyl)methyl-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropanecarboxylate). The insecticide was added to the slurry and stirred. Perlite 3-S was incorporated into the solution slurry of ammonium sulfate, water, cornstarch, and insecticide and stirred to produce a homogenous mixture. The mixture was poured into a drum granulator to promote granulation of the material. Hot air was blown into the granulation drum to remove the moisture of the mixture until the particles were free flowing and granules were formed. The granules were removed from the granulation drum and placed in a lab oven at 125° F. for further drying.
The second granulation technique performed during these tests is referred to as the drum over-coating granulation method. In Tests 62 and 63 ammonium sulfate carrier granules were produced by the following procedure.
Test #62
Approximately 200 grams of de-ionized water was heated to 200° F. Finely ground ammonium sulfate crystals were added (400 grams) to the water to produces a 67% solution/slurry. Corn starch (B810) was added (4.6 grams) (1% by weight) to the ammonium sulfate solution/slurry and homogenized to produce a homogenous mixture.
Approximately 2% active agent herbicide was added to the ammonium sulfate and corn starch solution/slurry to perform Test # 62. The herbicide contained TRIMEC. TRIMEC is composed of dimethylamine salt of 2-(2-methyl-4-chlorophenoxy)propionic acid, dimethylamine of 2,4-dichlorophenoxyacetic acid, dimethylamine salt of dicamba (3,6-dichloro-O-anisic acid). The herbicide was added to the slurry and stirred.
Perlite #5 was added (28 grams) to the drum granulator and preheated to aid in granulation and moisture removal of the mixture. The slurry/solution of ammonium sulfate, water, corn starch, and TRIMEC was poured onto the rolling bed of perlite. Hot air was blown into the granulation drum to remove the moisture of the mixture until the particles were free flowing and granules were formed. The granules were removed from the granulation drum and placed in a lab oven at 125° F. for further drying.
Test #63
Approximately 200 grams of de-ionized water was heated to 200° F. Finely ground ammonium sulfate crystals were added (400 grams) to the water to produces a 67% solution/slurry. Corn starch (B810) was added (4.6 grams) (1% by weight) to the ammonium sulfate solution/slurry and homogenized to produce a homogenous mixture.
Approximately 2% active agent insecticide was added to the ammonium sulfate and corn starch solution/slurry to perform Test 63. The insecticide was Permethrin ((3-phenoxyphenyl)methyl-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropanecarboxylate). The insecticide was added to the slurry of ammonium sulfate, water, and corn starch and stirred.
Perlite #5 was added (28 grams) to the drum granulator and preheated to aid in granulation and moisture removal of the mixture. The slurry/solution of ammonium sulfate, water, corn starch, and Permethrin was poured onto the rolling bed of perlite. Hot air was blown into the granulation drum to remove the moisture of the mixture until the particles were free flowing and granules were formed. The granules were removed from the granulation drum and placed in a lab oven at 125° F. for further drying.
Particles produced in Tests 60-63 were placed in a petri dish and submerged with de-ionized water and visually observed with a laboratory stereoscope to identify the initial release characteristics of the pesticide carrier granules. Visual observations of the granules that were submerged in water showed rapid particle breakdown, presumably enhanced by the release of stored energy within the particles. This particle breakdown increased the surface area of the inoculated materials containing the pesticide (herbicide or insecticide) by 2 to 10 times the surface area of the starting particles. Thus, excellent, fast pesticide release characteristics were observed.
While only a few exemplary embodiments of this invention have been described in detail, those skilled in the art will recognize that there are many possible variations and modifications which may be made in the exemplary embodiments while yet retaining many of the novel and advantageous features of this invention. Accordingly, it is intended that the following claims cover all such modifications and variations.
This is a continuation application of U.S. application Ser. No. 10/460,650 filed Jun. 13, 2003.
| Number | Date | Country | |
|---|---|---|---|
| 60388295 | Jun 2002 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 10460650 | Jun 2003 | US |
| Child | 11723294 | Mar 2007 | US |
