Coated fertilizer granule composition

Abstract

Embodiments of the present disclosure are directed to coated fertilizer granule compositions that include two polyurethane layers and an optional wax layer.

Description

[Technical field]

[0001] SUMMARY OF THE DISCLOSURE Embodiments of the present disclosure are directed to coated fertilizer granule compositions. [Background technology]

[0002] Coatings on fertilizer granules help control fertilizer release and reduce dust generation. Controlled release of fertilizer can, among other things, increase fertilizer efficiency, lower labor costs associated with fertilizer application, and / or reduce the amount of fertilizer applied. Reducing dust generation aids in fertilizer handling and increases the shelf life of the fertilizer. However, with all the improvements in coatings, there is a continuing need for new coated fertilizers and new methods of making coated fertilizers that can provide improvements in both dust control and controlled release. Summary of the Invention

[0003] The present disclosure provides a coated fertilizer granule composition that can provide improvements in both dust control and controlled release. The coated fertilizer granule composition includes a fertilizer granule, a first polyurethane layer in contact with the fertilizer granule to provide a coating concentration of the first layer on the fertilizer granule of 0.75-1.5 wt % based on the total weight of the coated fertilizer granule composition, the first polyurethane layer having an outer surface, a second polyurethane layer at least partially covering the outer surface of the first polyurethane layer and providing a coating concentration of the second layer of the second polyurethane layer that is 0.75-1.5 wt % based on the total weight of the coated fertilizer granule composition, and the first polyurethane layer and the second polyurethane layer provide a total coating concentration on the fertilizer granule of 1.5-3.0 wt % based on the total weight of the coated fertilizer granule composition, and the first polyurethane layer and the second polyurethane layer are interposed between the first polyurethane layer and the second polyurethane layer to provide a total coating concentration on the fertilizer granule of 1.5-3.0 wt % based on the total weight of the coated fertilizer granule composition. Each is formed separately from the reaction product of a reaction mixture including a polyol mixture consisting of 40-60 weight percent 1,4-butanediol, based on the total weight of the polyol mixture, and 60-40 weight percent, based on the total weight of the polyol mixture, of a propylene oxide based polyether polyol having an equivalent weight of 700-1500 g / eq, the weight percent being based on the total weight of the polyol mixture, a tertiary amine catalyst, and a polymethylene polyphenylisocyanate mixture including 8-20 weight percent ortho-para methylene diphenyl diisocyanate, the weight percent being based on the total weight of the polymethylene polyphenylisocyanate mixture, to provide a reaction mixture having an Isocyanate Index in the range of 90-200.

[0004] The above summary of the present disclosure is not intended to describe each disclosed embodiment or to describe all implementations of the present disclosure. More specifically, the present specification illustrates exemplary embodiments. In several places throughout the application, guidance is provided through lists of examples, which examples can be used in various combinations. In each instance, the recited list serves only as a representative group and should not be interpreted as an exclusive list. [Brief description of the drawings]

[0005] [Figure 1] FIG. 1 illustrates a cross-sectional view of an example of a coated fertilizer granule composition according to one or more embodiments of the present disclosure. [Diagram 2] FIG. 1 illustrates a cross-sectional view of an example of a coated fertilizer granule composition according to one or more embodiments of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0006] A coated fertilizer granule composition (CFGC) is disclosed herein. Advantageously, the CFGC disclosed herein can provide improved control of both fertilizer release and dust generation. Referring to FIG. 1, a cross-sectional view of an embodiment of a coated fertilizer granule composition (CFGC) 100 is shown, the coated fertilizer granule 110 includes a first polyurethane layer 120 in contact with the fertilizer granule 110, the first polyurethane layer 120 having an outer surface 130, and a second polyurethane layer 140 at least partially covering the outer surface 130 of the first polyurethane layer 120. 2, a cross-sectional view of an embodiment of a CFGC 200 is shown that includes a fertilizer granule 210, a first polyurethane layer 220 in contact with the fertilizer granule 210, the first polyurethane layer 220 having an outer surface 230, a second polyurethane layer 240 at least partially covering the outer surface 230 of the first polyurethane layer 220, and a wax layer 250 at least partially covering the second polyurethane layer 240. Each of the above structures is described herein below, with element numbers of like structures in FIG. 1 and FIG. 2 being referenced simultaneously (e.g., fertilizer granule 110 / 210; first polyurethane layer 120 / 220; outer surface 130 / 230 and second polyurethane layer 140 / 240).

[0007] The CFGS 100 / 200 disclosed herein includes a fertilizer granule 110 / 210. The fertilizer granule 110 / 210 can be a homogenous or blended granule that includes one or more of a urea source, a nitrogen source, a phosphorus source, or a potassium source, such as, for example, ammonium nitrate, ammonium sulfate, ammonium nitrate sulfate, calcium nitrate, calcium ammonium nitrate, urea-formaldehyde, monoammonium phosphate, diammonium phosphate, polyphosphate compounds, rock phosphate, single superphosphate, triple superphosphate, potassium nitrate, potassium chloride, potassium sulfate, or combinations thereof. In some embodiments, the fertilizer granule 110 / 210 can include urea. For example, the fertilizer granule 110 / 210 can have a nitrogen:phosphorus:potassium ratio of 46:0:0. The amount of nitrogen source, phosphorus source, or potassium source included in the fertilizer granule 110 / 210 can vary based on the intended end use, but can be from 0 to 60% by weight of each component, based on the total weight of the fertilizer granule 110 / 210.

[0008] Additionally, the fertilizer granule 110 / 210 may include magnesium sulfate along with an optional source of one or more trace elements, which may include micronutrients such as boron, calcium, chlorine, cobalt, copper, iron, manganese, molybdenum, nickel, sodium, zinc, or combinations thereof. These nutrients may be provided in elemental form or in salt form, such as sulfates, nitrates, or halides. The amount of the micronutrients may vary depending on the intended end use. For example, the amount of the micronutrients may be 0.1-5% by weight based on the total weight of the fertilizer granule 110 / 210. Fillers may also be utilized in the fertilizer granule 110 / 210, such as bentonite, calcite, calcium oxide, calcium sulfate (anhydrous or hemihydrate), dolomite, talc, sand, or combinations thereof.

[0009] Other components of the fertilizer granules 110 / 210 can include, for example, regenerated fertilizer particles that may act as surfactants, nucleating agents, or nucleating agent sources, nucleating soil conditioners such as calcium carbonate, activated carbon, elemental sulfur, biocides such as insecticides, herbicides, or fungicides, wicking agents, wetting agents, heat stabilizers, adhesives such as cellulose, polyvinyl alcohol, fats, oils, gum arabic, vinylidene UV stabilizers, antioxidants, reducing agents, colorants, binders such as organic chlorides, zein, gelatin, chitosan, polyethylene oxide polymers, and acrylamide polymers and copolymers, and the like, and combinations thereof.

[0010] The fertilizer granules 110 / 210 can have a wide variety of shapes and / or sizes depending on their intended use. In some embodiments, the fertilizer granules 110 / 210 are substantially spherical. The fertilizer granules 110 / 210 can have an average particle size of 0.5 to 6.0 millimeters (mm). All individual values ​​and subranges between 0.5 and 6.0 mm are included, for example, the fertilizer granules 110 / 210 can have an average particle size of 0.5, 1.0, or 1.5 mm (lower limit) to 6.0, 5.5, or 5.0 mm (upper limit). In some embodiments, at least 90% by weight of the fertilizer granules 110 / 120 have a particle size of 2.0 to 4.0 mm. The particle size can be determined according to the "Size Analysis-Sieve Method" IFDC S-107 published by the International Fertilizer Development Center (IFDC), which is a common and internationally accepted method used to determine fertilizer particle size.

[0011] In various embodiments, the CFGS 100 / 200 includes a first polyurethane layer 120 / 220 in contact with the fertilizer granule 110 / 210, the first polyurethane layer 120 / 220 having an outer surface 130 / 230, and a second polyurethane layer 140 / 240 at least partially covering the outer surface 130 / 230 of the first polyurethane layer 120 / 220. As used herein, the first polyurethane layer 120 / 220 in contact with the fertilizer granule 110 / 210 includes at least partially covering 80%-100% of a surface area of ​​the fertilizer granule 110 / 210, e.g., an outermost area. All individual values ​​and subranges between 80% and 100% are included, for example, the first polyurethane layer 120 / 220 can cover 80, 90, or 95% (lower limit) to 100, 99, or 98% (upper limit) of the surface area of ​​the fertilizer granule 110 / 120. Similarly, as used herein, the second polyurethane layer 140 / 240 covering at least a portion of the outer surface 130 / 230 of the first polyurethane layer 120 / 220 includes covering 80% to 100% of the surface area, e.g., the outermost area, of the outer surface 130 / 230 of the first polyurethane layer 120 / 220. All individual values ​​and subranges between 80% and 100% are included, for example, the second polyurethane layer 140 / 240 can cover 80, 90, or 95% (lower limit) to 100, 99, or 98% (upper limit) of the outer surface 130 / 230 of the first polyurethane layer 120 / 220.

[0012] In a given embodiment, the first polyurethane layer 120 / 220 and the second polyurethane layer 140 / 240 can provide a total coating concentration on the fertilizer granule 110 / 210 of 1.5 to 3.0 weight percent based on the total weight of the CFGC 100 / 200. All individual values ​​and subranges from 1.5 to 3.0 weight percent are included herein for the total coating concentration on the fertilizer granule 110 / 210. For example, the first polyurethane layer 120 / 220 and the second polyurethane layer 140 / 240 can provide a total coating concentration on the fertilizer granule 110 / 210 having a lower limit of 1.5, 1.6, 1.7, 1.75, 1.8, 1.85, 1.9, or 1.99 weight percent based on the total weight of the CFGC, up to an upper limit of 3.0, 2.75, 2.65, 2.55, 2.45, 2.35, 2.25, 2.15, 2.10, 2.05, or 2.01 weight percent based on the total weight of the CFGC 100 / 200.

[0013] For various embodiments, the first polyurethane layer 120 / 220 contacting the fertilizer granule 110 / 210 provides a first layer coating concentration on the fertilizer granule 110 / 210 of 0.75 to 1.5 weight percent based on the total weight of the CFGC 100 / 200. All individual values ​​and subranges of the first layer coating concentration of 0.75 to 1.5 weight percent on the fertilizer granule 110 / 210 for various embodiments are included herein. For example, the first polyurethane layer 120 / 220 can provide a first layer coating concentration on the fertilizer granule 110 / 210 of 0.75, 0.8, 0.85, 0.9, 0.95, or 0.99 wt.% (lower limit) to 1.5, 1.45, 1.40, 1.3, 1.25, 1.15, 1.10, 1.05, or 1.01 wt.% (upper limit) based on the total weight of the CFGC 100 / 200. For example, the first layer coating concentration of the first polyurethane layer 120 / 220 on the fertilizer granule 110 / 210 can be 0.9-1.1 wt.% based on the total weight of the CFGC. In further embodiments, the first layer coating concentration of the first polyurethane layer 120 / 220 can be 1.0-1.35 wt.% based on the total weight of the CFGC. In one embodiment, the first polyurethane layer 120 / 220 provides a first layer coverage concentration of fertilizer granules 110 / 210 of 1% by weight based on the total weight of the CFGC.

[0014] In various embodiments, the second polyurethane layer 140 / 240 at least partially covering the outer surface 130 / 230 of the first polyurethane layer 120 / 220 provides a second layer coating concentration of the second polyurethane layer 140 / 240 of 0.75-1.5 wt % based on the total weight of the CFGC. All individual values ​​and subranges of the second layer coating concentration on the fertilizer granule 110 / 210 of 0.75-1.5 wt % for various embodiments are included herein. For example, the second polyurethane layer 140 / 240 can provide a coating concentration of the second layer on the fertilizer granule 110 / 210 of 0.75, 0.8, 0.85, 0.9, 0.95, or 0.99 wt.% (lower limit) to 1.5, 1.45, 1.40, 1.3, 1.25, 1.15, 1.10, 1.05, or 1.01 wt.% (upper limit) based on the total weight of the CFGC 100 / 200. For example, the coating concentration of the second layer of the second polyurethane layer 140 / 240 on the fertilizer granule 110 / 210 can be 0.9-1.1 wt.% based on the total weight of the CFGC 100 / 200. In further embodiments, the coating concentration of the second layer of the second polyurethane layer 140 / 240 can be 1.0-1.35 wt.% based on the total weight of the CFGC 100 / 200. In one embodiment, the second polyurethane layer 140 / 240 provides a second layer coverage on the fertilizer granule 110 / 210 of 1% by weight based on the total weight of the CFGC 100 / 200.

[0015] In various embodiments, each of the first polyurethane layer 120 / 220 and the second polyurethane layer 140 / 240 is formed separately to provide each of the first polyurethane layer 120 / 220 and the second polyurethane layer 140 / 240 as a separate layer from a reaction product of a reaction mixture including a polyol mixture, a tertiary amine catalyst, and a polymethylene polyphenylisocyanate mixture (PPM). For various embodiments, the coating concentration of the first layer of the first polyurethane layer 120 / 220 of the CFGC 100 / 200 and the coating concentration of the second layer of the second polyurethane layer 140 / 240 may be the same or different. Preferably, the coating concentration of the first layer of the first polyurethane layer 120 / 220 and the coating concentration of the second layer of the second polyurethane layer 140 / 240 of the CFGC 100 / 200 are the same. For example, as described herein, the first polyurethane layer 120 / 220 can provide a first layer coating concentration on the fertilizer granule 110 / 210 of 1 weight based on the total weight of the CFGC 100 / 200, and the second polyurethane layer 140 / 240 can provide a second layer coating concentration on the fertilizer granule 110 / 210 of 1 weight based on the total weight of the CFGC 100 / 200, and the first polyurethane layer 120 / 220 and the second polyurethane layer 140 / 240 can provide a total coating concentration on the fertilizer granule 110 / 210 of 2 weight percent based on the total weight of the CFGC 100 / 200.

[0016] For various embodiments, the reaction mixture can include 20-40 wt. % polyol mixture, 0.5-4 wt. % tertiary amine catalyst, and 56-79.5 wt. % PPM, based on the total weight of the reaction mixture, where the wt. % values ​​of polyol mixture, tertiary amine catalyst, and PPM add up to 100 wt. %. For various embodiments, all individual values ​​and subranges of the wt. % for each of the polyol mixture, tertiary amine catalyst, and PPM are included herein. For example, the reaction mixture can include from 20, 25, 27.4, or 28% by weight (lower limit) to 40, 35, or 30% by weight (upper limit) of the polyol mixture based on the total weight of the reaction mixture; from 0.5, 1.0, 2.0, 2.5, 2.9, or 3% by weight (lower limit) to 4, 3.5, 3.2, 3.1, or 3.05% by weight (upper limit) of the tertiary amine catalyst based on the total weight of the reaction mixture; and from 56, 60, 65, or 69% by weight (lower limit) to 79.5, 75, 70, or 69.55% by weight (upper limit) of the PPM based on the total weight of the reaction mixture.

[0017] In various embodiments, the reaction mixture used to form each of the first polyurethane layer 120 / 220 and the second polyurethane layer 140 / 240 can be the same. In other words, the same reaction mixture can be used to form both the first polyurethane layer 120 / 220 and the second polyurethane layer 140 / 240. In alternative embodiments, the reaction mixture used to form each of the first polyurethane layer 120 / 220 and the second polyurethane layer 140 / 240 can be different.

[0018] In various embodiments, the polyol mixture comprises 40-60 wt% 1,4-butanediol (BDO) and 60-40 wt% propylene oxide-based polyether polyol (Poly 1) having an equivalent weight of 700-1500 g / eq, where the wt% values ​​are based on the total weight of the polyol mixture. All individual values ​​and subranges between 40-60 wt% BDO and 60-40 wt% Poly 1 are included herein. For example, the polyol mixture can contain 40, 45, or 49 wt% (lower limit) to 60, 57, 55, or 51 wt% BDO and 40, 45, or 49 wt% (lower limit) to 60, 57, 55, or 51 wt% Pol 1. In certain embodiments, the polyol mixture described herein can comprise 45-55 wt% BDO and 55-45 wt% Poly 1. In a further embodiment, the polyol mixture contains 50% by weight BDO and 50% by weight Pol 1. For the various embodiments, the weight percentage values ​​of BDO and Poly 1 alone add up to a total of 100% by weight polyol mixture.

[0019] For various embodiments, the BDO has a nominal or average hydroxyl functionality of 1 to 4. All individual values ​​and subranges from 1 to 4 are included, for example, the nominal hydroxyl functionality can be from 1, 1.5, or 1.8 (lower limit) to 4, 3.5, 3, or 2.2 (upper limit). An embodiment specifies that the BDO has a nominal hydroxyl functionality of 2 or about 2. The BDO can have an average hydroxyl number of 1100 to 1300 mg KOH / g. All individual values ​​and subranges from 1100 to 1300 mg KOH / g are included, for example, the average hydroxyl number can be from 1100, 1150, 1200, or 1245 mg KOH / g (lower limit) to 1300, 1275, or 1250 mg KOH / g (upper limit). The average hydroxyl number as KOH can be determined according to ASTM D4274. An embodiment specifies that the BDO has an average hydroxyl number of 1245 mg KOH / g. The BDO has an equivalent weight of 35 to 55 g / eq. All individual values ​​and subranges between 35 and 55 g / eq are included, for example, the equivalent weight can be from 35, 40, or 45 g / eq (lower limit) to 55, 50, or 46 g / eq (upper limit). An embodiment specifies that the BDO has an equivalent weight of about 45.06 g / eq.

[0020] For various embodiments, Poly 1 refers to a polyether polyol produced by polymerization of propylene oxide and optionally another alkylene oxide and an initiator. For various embodiments, the propylene oxide is 80% or more by weight of the total alkylene oxide content of Pol 1. Examples of other alkylene oxides that may be utilized in forming Pol 1 include ethylene oxide, butylene oxide, and combinations thereof. In various embodiments, Pol 1 can be a trifunctional poly(propylene oxide) homopolymer polyether polyol. Additionally, embodiments provide that the total alkylene oxide content used in forming Pol 1 can be 80-100% by weight propylene oxide. For example, the propylene oxide can be 80, 90, or 95% by weight (lower limits) to 100, 99, 98, or 97% by weight (upper limits) of the total alkylene oxide content used in forming Pol 1, including all individual values ​​and subranges from 80 to 100% by weight. One or more embodiments provide that propylene oxide is 100% by weight of the total alkylene oxide content used in forming Pol 1 (i.e., no other alkylene oxides are utilized). Examples of initiators include water, glycerin, ethylene glycol, propylene glycol, trimethylolpropane, pentaerythritol, or combinations thereof. The initiator may have a functionality of 2-4.

[0021] Pol 1 has a nominal or average hydroxyl functionality of 2 to 4. All individual values ​​and subranges from 2 to 4 are included, for example, Pol 1 may have a nominal hydroxyl functionality of 2.0, 2.5, or 2.8 (lower limit) to 4.0, 3.5, or 3.2 (upper limit). One or more embodiments provide Pol 1 with a nominal hydroxyl functionality of 3. Pol 1 can be prepared using known equipment, reaction conditions, and reaction components. Pol 1 is commercially available. Examples of commercially available propylene oxide-based polyether polyols include, but are not limited to, propylene oxide-based polyether polyols sold under the trade name VORANOL™, such as VORANOL™ 230-056 available from Dow®.

[0022] Pol 1 may have an average hydroxyl number of 10-100 mg KOH / g. All individual values ​​and subranges between 10-100 mg KOH / g are included, for example, Pol 1 may have an average hydroxyl number of 10, 20, 30, 40, 50, or 54 mg KOH / g (lower limit) to 100, 95, 85, 75, 65, or 58 mg KOH / g (upper limit). Average hydroxyl number as KOH may be determined according to ASTM D4274. One or more embodiments provide that Pol 1 has an average hydroxyl number of 54.5-57.5 mg KOH / g. Pol 1 has an equivalent weight of 800-1200 g / eq. All individual values ​​and subranges from 800 to 1200 g / eq are included, for example, the equivalent weight can be from 800, 850, 900, 950, or 1000 g / eq (lower limit) to 1200, 1150, 1100, 1050, or 1003 g / eq (upper limit). In one embodiment, Pol 1 has an equivalent weight of about 1002 g / eq. In an additional embodiment, Pol 1 can be a trifunctional poly(propylene oxide) homopolymer polyether polyol having an equivalent weight of 800 to 1200 g / eq.

[0023] For various embodiments, the tertiary amine catalyst can be selected from the group consisting of triethanolamine, triisopropanolamine, N-methyl-diethanolamine, N-ethyldiethanolamine, N,N-dimethyl-ethanolamine, and combinations thereof.

[0024] In various embodiments, the PPM comprises 8-20 weight percent ortho-para-methylene diphenyl diisocyanate (o,p'-MDI), the weight percent being based on the total weight of the PPM, to provide a reaction mixture having an Isocyanate Index in the range of 90-200. All individual values ​​and subranges inclusive of 8-20 weight percent o,p'-MDI PPM are included herein. For example, the PPM can have a lower limit of 8, 9, 10, or 11 weight percent o,p'-MDI based on the total weight of the PPM, and an upper limit of 20, 18, 15, or 12 weight percent o,p'-MDI based on the total weight of the PPM.

[0025] For various embodiments, the PPM has an isocyanate functionality of at least 1.0. For example, the PPM can have an isocyanate functionality of 1.0 to 5.0. All individual values ​​and subranges between 1.0 and 5.0 are included, for example, the PPM can have an isocyanate functionality of 1.0, 1.5, or 2.0 (lower limits) to 5.0, 4.0, 3.5, 3.0, or 2.5 (upper limits).

[0026] For a given weight percent of o,p'-MDI and isocyanate functionality, the PPM may contain 10-15 weight percent o,p'-MDI and an isocyanate functionality of 2-2.5.

[0027] The PPM of various embodiments may further include an isocyanate index of 90 to 200. All individual values ​​and subranges between 90 and 200 are included, for example, the PPM may provide an isocyanate index of 90, 100, 110, or 120 (lower limit) to 200, 190, 180, or 170 (upper limit). One or more embodiments provide that the PPM may provide an isocyanate index of 140. The isocyanate index may be determined as [isocyanate groups / active hydrogen groups x 100]. The active hydrogen groups include those from Pol 1 and the tertiary amine catalyst(s).

[0028] The PPM may have an equivalent weight of 80 g / eq to 2000 g / eq, including all individual values ​​and subranges between 80 and 2000 g / eq, for example, the PPM may have an equivalent weight of 80, 90, 100, 115, 120, 130, or 133 (lower limits) to 2000, 1500, 1000, 500, 200, or 135 g / eq (upper limits).

[0029] The PPM may have an NCO content of 20 to 45 weight percent, based on the total weight of the PPM, including all individual values ​​and subranges between 20 and 45 weight percent, for example, the PPM may have an NCO content of 20, 25, 30, or 32 weight percent (lower limits) to 45, 40, 35, or 33 weight percent (upper limits), based on the total weight of the PPM.

[0030] Examples of PPMs having o,p'-MDI provided herein include, but are not limited to, methylene diphenyl diisocyanate (MDI), polymeric MDI, polymethylene polyphenyl isocyanate, and polymethylene polyphenyl isocyanate-containing MDI. PPMs may be prepared by known processes. PPMs can be commercially obtained. Examples of commercially available PPMs include, but are not limited to, polyisocyanates under the trade name PAPI™, such as PAPI™ 94 available from DOW Corporation, among other commercially available isocyanates.

[0031] The embodiments of the present disclosure also include the following CFGCs based on the information provided herein: In one example of CFGC 100 / 200, the coating concentration of the first layer is 0.9-1.1 wt % based on the total weight of CFGC 100 / 200, the coating concentration of the second layer is 0.9-1.1 wt % based on the total weight of CFGC 100 / 200, and the total coating concentration on the fertilizer granule 110 / 210 is 0.9-1.1 wt % based on the total weight of CFGC 100 / 200. 1.8-2.2 wt% based on the total weight of 100 / 200, the reaction mixture comprises 25-30 wt% polyol mixture based on the total weight of the reaction mixture, the polyol mixture consisting of 48-52 wt% BDO and 48-52 wt% trifunctional poly(propylene oxide) homopolymer polyether polyol having an equivalent weight of 900-1100 g / eq, where the wt% are based on the total weight of the polyol mixture; 2.9-3.1 wt% tertiary amine catalyst based on the total weight of the reaction mixture, and 65-75 wt% PPM based on the total weight of the reaction mixture, the PPM consisting of 13-15 wt% o,p'-MDI based on the total weight of the PPM. In another example of CFGC 100 / 200, the coating concentration of the first layer of the first polyurethane layer 120 / 220 is 1.0-1.35 wt% based on the total weight of CFGC 100 / 200, and the coating concentration of the second layer of the second polyurethane layer 140 / 240 is 1.0-1.35 wt% based on the total weight of CFGC 100 / 200, and the total coating concentration on the fertilizer granule 110 / 210 is 2.0-2.7 wt% based on the total weight of CFGC 100 / 200. In a further example of CFGC 100 / 200, the coating concentration of the first layer is 1 wt% based on the total weight of CFGC 100 / 200.The coating concentration of the second layer is 1 wt% based on the total weight of the CFGC 100 / 200, the total coating concentration on the fertilizer granule 110 / 210 is 2 wt% based on the total weight of the CFGC 100 / 200, and the reaction mixture comprises 27.4 wt% polyol mixture based on the total weight of the reaction mixture, the polyol mixture consisting of 50 wt% 1,4-butanediol and 50 wt% trifunctional poly(propylene oxide) homopolymer polyether polyol having an equivalent weight of 900-1100 g / eq, the weight % being based on the total weight of the polyol mixture, 3.05 wt% tertiary amine catalyst based on the total weight of the reaction mixture, and 69.55 wt% PPM based on the total weight of the reaction mixture, the PPM consisting of 14 wt% o,p'-MDI based on the total weight of the PPM.

[0032] 2, the CFGC 200 of the present disclosure can further include a wax layer 250 at least partially covering the second polyurethane layer 240. For various embodiments, the second polyurethane layer 240 separates the wax layer 250 from the fertilizer granule 210 and the first polyurethane layer 220. In other words, each of the fertilizer granule 210, the first polyurethane layer 220, and the second polyurethane layer 240 is separate from the wax layer 250.

[0033] For various embodiments, the wax layer 250 at least partially covers the second polyurethane layer 240 to provide a wax layer concentration of 0.5-1.0 wt % based on the total weight of the CFGC 200. In one embodiment, the wax layer 250 at least partially covers the second polyurethane layer 240 to provide a wax layer concentration of 0.5 wt % based on the total weight of the CFGC 200.

[0034] Examples of waxes that may be utilized in the wax layer 250 include insect and animal waxes, such as beeswax, vegetable waxes, such as candelilla, carnauba, Japan wax, Orycurea wax, Douglas fir bark wax, rice bran wax, jojoba, castor wax, and white bayberry wax, montan wax, peat wax, ozokerite wax, and ceresin wax, and petroleum waxes, such as paraffin wax, microcrystalline wax, semicrystalline wax, and synthetic waxes, such as polyethylene wax, Fischer-Tropsch wax, copolymer waxes of ethylene, propylene, and / or acrylic acid, and mixtures of petroleum wax and ethylene-vinyl acetate copolymers. In one group of embodiments, petroleum wax and / or synthetic waxes are used. One or more embodiments provide that the wax is an alpha olefin wax. The alpha olefin wax may be a straight chain hydrocarbon having 20 to 40 carbons. For various embodiments, the wax layer comprises a polyolefin wax layer having 20-40 carbon atoms and a dropping point of 60-70 degrees Celsius (° C.) measured according to ASTM D3954.

[0035] The first polyurethane layer 120 / 220, the second polyurethane layer 140 / 240 and the wax layer 250 of the CFGC 100 / 200, respectively, can be formed using known coating techniques. Such coating techniques include wet particle coating techniques in which a reaction mixture is applied to the fertilizer granule 110 / 210, as described herein. In a typical procedure, the fertilizer granule 110 / 210 is heated to a temperature of 50-100° C. in a heated drum coater while mixing. Preferably, the fertilizer granule 110 / 210 is heated to 80° C. while mixing in the heated drum coater. The first polyurethane layer 120 / 220 and the second polyurethane layer 140 / 240, respectively, are formed separately as follows:

[0036] To form the first polyurethane layer 120 / 220, a first portion (e.g., 50% by weight) of the PPM for forming the first polyurethane layer 120 / 220 is sprayed onto the fertilizer granules 110 / 210 that are mixing in a heated drum coater. Once the first portion of the PPM has been added to the fertilizer granules 110 / 210, the contents of the heated drum coater are allowed to mix for a first mixing interval of 1-10 minutes. After the first mixing interval, a mixture of BDO, Pol 1, and the tertiary amine catalyst for the first polyurethane layer 120 / 220 is sprayed onto the contents of the heated drum coater. The contents of the heated drum coater are allowed to mix for a second mixing interval of 1-10 minutes. After the second mixing interval, a second portion (e.g., 50% by weight) of the PPM for forming the first polyurethane layer 120 / 220 is sprayed onto the contents of the heated drum coater for a third mixing interval of 15 seconds to 5 minutes, thereby forming the first polyurethane layer 120 / 220.

[0037] To form the second polyurethane layer 140 / 240, a first portion (e.g., 50% by weight) of the PPM for forming the second polyurethane layer 140 / 240 is sprayed onto the contents being mixed in the heated drum coater. Once the first portion of the PPM has been added, the contents being mixed in the heated drum coater are allowed to mix for a fourth mixing interval of 15 seconds to 5 minutes. After the fourth mixing interval, a mixture of BDO, Pol 1, and the tertiary amine catalyst of the second polyurethane layer 140 / 240 is sprayed onto the contents of the heated drum coater. The contents of the heated drum coater are allowed to mix for a fifth mixing interval of 15 seconds to 5 minutes. After the fifth mixing interval, a second portion (e.g., 50% by weight) of the PPM for forming the second polyurethane layer 140 / 240 is sprayed onto the contents of the heated drum coater, which is allowed to mix for a sixth mixing interval of 15 seconds to 5 minutes, thereby forming the second polyurethane layer 140 / 240. After the second polyurethane layer 140 / 240 is formed, a wax layer 250 can be added to the CFGC 100 / 200, if desired, by adding any of the waxes in the amounts provided herein to the contents of the heated drum coater, which are allowed to mix for a seventh time interval of 1-6 minutes. After the seventh time interval, the heat to the heated drum coater can be turned off and the rotating contents of the drum coater can be allowed to cool naturally to 60° C., thereby forming the wax layer 250 as discussed herein. The contents of the drum coater can then be scooped from the drum coater, spread onto a clean tray, and allowed to cure at room temperature (23° C.), for example, for at least 7 days. EXAMPLES

[0038] material The following materials were used in the following Examples ("Ex") and Comparative Examples ("CE"):

[0039] [Table 1]

[0040] Examples and Comparative Examples of Coated Fertilizer Granule Composition (CFGC) Table 2 provides the formulation percentages used in forming the Example (Ex) and Comparative Example (CE) with Fertilizer #1. Table 3 provides the formulation percentages used in forming the Example (Ex) and Comparative Example (CE) with Fertilizer #2. For Tables 2 and 3, the weight percentages of BDO and Pol. 1 found in the Polyurethane Layer 1 (PU Layer 1) and Polyurethane Layer 2 (PU Layer 2) columns are based on the total weight of the polyol mixture. The weight percentages of isocyanate (1 or 2), BDO, Polyol 1, and TEA are based on the total weight of the reaction mixture used in forming PU Layer 1 and PU Layer 2, and the weight percentages of total PU and total wax are based on the total weight of the CFGC for each of the Examples and Comparative Examples.

[0041] [Table 2]

[0042] [Table 3]

[0043] The examples and comparative examples from Tables 2 and 3 are prepared using a drum roller process using a cylindrical steel drum roller 16 1 / 8 inches in diameter and 5 1 / 8 inches deep with a 9 3 / 8 inch diameter circular open face plate and five equally spaced 1 / 2 inch bevels. For each example and comparative example, 1 kilogram (Kg) of fertilizer granules is dried in an oven at 80°C for at least 6 hours before starting the coating process. For the coating process, the drum coater is preheated to 70°C. The oven-dried fertilizer (1 Kg for a given example or comparative example) is added to the heated drum coater, after which the rotation of the drum coater is set to 35 revolutions per minute (rpm). The drum coater temperature is then increased to heat and maintain the fertilizer granules in the drum coater at 80°C for the coating process described herein, where the temperature is continuously monitored using an infrared thermometer.

[0044] The amounts of ingredients used in forming each of the polyurethane layers for the Examples and Comparative Examples are measured into syringes using an analytical balance according to Table 4 for Fertilizer #1 and Table 5 for Fertilizer #2.

[0045] [Table 4]

[0046] [Table 5]

[0047] Once the temperature of the fertilizer granules in the drum coater reaches 80° C., the ingredients forming the first and second polyurethane layers according to Table 3 are injected onto the rotating fertilizer granules in the order and coating times shown in Table 6. BDO (if present), each of Pol. 1 (if present) and TEA for each of the polyurethane layers are injected as a mixture.

[0048] [Table 6]

[0049] After coating of the second polyurethane layer is complete, a wax layer is formed by adding the amount of wax shown in Table 3 to the contents of the drum coater. The drum coater is operated for 180 seconds to form the wax layer, after which the heat to the drum coater is turned off and the rotating contents of the drum coater are allowed to cool naturally to 60° C. The contents of the drum coater are scooped from the drum coater, spread onto a clean tray, and allowed to cure at room temperature (23° C.) for 7 days before being tested as described herein.

[0050] Testing of coated fertilizer granules Dust Measurement Example 1 and Comparative Examples A-F were tested for dust abrasion as follows: Dust abrasion measurements are carried out in an EDEMET ball mill using a grinding jar (tall stainless steel 2 liter hydration bottle). 4.75 mm steel bearings were used as the grinding media. Details of the grinding chamber are shown in Table 7 along with the amounts of different materials used in the dust abrasion test.

[0051] [Table 7]

[0052] The dust abrasion test was performed as follows: A mesh #20 (850 micrometer straight weave opening) screen was used to remove existing fines from the test sample of CFGC. After screening, the test sample of CFGC was rifled multiple times on a chute rifler to obtain approximately 100 grams of CFGC. An analytical balance was used to measure the mass m of the test sample of CFGC as provided in Table 7. i and the mass of clean grinding media m g The mass of material retained on each screen is measured using an analytical balance. The test sample and grinding media are added to the grinding jar. The grinding jar is placed on a ball mill set at a speed of 70 revolutions per minute (rpm). The grinding jar is rotated at 70 rpm for 30 minutes. After 30 minutes, the contents of the grinding jar are removed onto the top screen of a stack of three screens having the following sequence from top to bottom: mesh #5 (4000 micrometer linear weave openings) screen; mesh #20 (850 micrometer linear weave openings) screen; and mesh #140 (105 micrometer linear weave openings) screen. The stack of three screens is manually shaken for 5 minutes, after which the mass of material retained on each screen is measured using an analytical balance. Where: m 20 Calculate the total dust abrasion of the test specimen of the CFGC according to equation (1), where is the mass retained on the mesh #20 screen.

[0053]

number

[0054] The dust abrasion test results for Example 1 and Comparative Examples A through F are reported in Table 8.

[0055] accelerated release The accelerated release of coated fertilizer #1 is measured by immersing the coated fertilizer in water at 23°C containing a dimethylformamide (DMF) buffer solution to accelerate the release of ammonium sulfate contained within the coated fertilizer sample. The IR absorbance of ammonium sulfate was recorded as a function of time using a Thermo Nicolet 6700 FTIR spectrometer. -1 Intensity of ammonium sulfate at 1650cm -1 The intensity of dimethylformamide (DMF) at 100 nm was recorded. DMF is used as an internal standard for normalization.

[0056] The accelerated release results for Example 1 and Comparative Examples A through F are reported in Table 8.

[0057] [Table 8]

[0058] The data in Table 8 show that Example 1 advantageously provided improved, e.g., reduced fertilizer release at 60 minutes, and increased dust control, as compared to each of Comparative Examples A through F.

[0059] Controlled Release The controlled release of coated fertilizer #2 is measured as follows: 10 grams (g) of coated fertilizer #2 is placed in 100 milliliters (mL) of distilled water. The refractive index of the mixture is measured at 14 and 28 days using a Reichert Technologies AR200 Handheld Refractometer. The percent release is calculated using equation (2), where Y=refractive index. Each sample is tested in triplicate, and the average percent release of each sample is recorded.

[0060]

number

[0061] The controlled release results of Example 2 and Comparative Examples G-J are reported in Table 9.

[0062] [Table 9]

[0063] The data in Table 9 show that Example 2 provides fertilizer with improved controlled release at both 14 and 28 days compared to each of Comparative Examples GJ.

Claims

1. A coated fertilizer granule composition, Fertilizer granules and, A first polyurethane layer in contact with the fertilizer granules, for providing a coating concentration of 0.75 to 1.5% by weight of the first layer on the coated granules based on the total weight of the coated fertilizer granule composition, wherein the first polyurethane layer has an outer surface, A second polyurethane layer that at least partially covers the outer surface of the first polyurethane layer and provides a second polyurethane layer coating concentration of 0.75 to 1.5% by weight based on the total weight of the coated fertilizer granule composition, wherein the first polyurethane layer and the second polyurethane layer provide a total coating concentration of 1.5 to 3.0% by weight on the fertilizer granules based on the total weight of the coated fertilizer granule composition, and further comprising, The first polyurethane layer and the second polyurethane layer are each formed separately from the reaction products of the reaction mixture, and the reaction mixture is A polyol mixture, Based on the total weight of the polyol mixture, 40 to 60% by weight of 1,4-butanediol and A polyol mixture comprising a propylene oxide-based polyether polyol having an equivalent weight of 700 to 1500 g / eq in 60 to 40% by weight, wherein the weight percentage is based on the total weight of the polyol mixture, and a propylene oxide-based polyether polyol. Tertiary amine catalysts and A coated fertilizer granule composition comprising a polymethylene polyphenyl isocyanate mixture containing 8 to 20% by weight of ortho-paramethylenediphenyl diisocyanate, wherein the reaction mixture has an isocyanate index in the range of 90 to 200, based on the total weight of the polymethylene polyphenyl isocyanate mixture.

2. The coated fertilizer granule composition according to claim 1, wherein the polyol mixture comprises 45 to 55% by weight of the 1,4-butanediol and 55 to 45% by weight of the propylene oxide-based polyether polyol.

3. The coated fertilizer granule composition according to claim 1, wherein the propylene oxide-based polyether polyol is a trifunctional poly(propylene oxide) homopolymer polyether polyol having an equivalent amount of 800 to 1200 g / eq.

4. The coated fertilizer granule composition according to claim 1, wherein the polymethylene polyphenyl isocyanate mixture contains 10 to 15% by weight of the ortho-paramethylene diphenyl diisocyanate and an isocyanate functional value of 2 to 2.

5.

5. Based on the total weight of the reaction mixture, the reaction mixture is 20 to 40% by weight of the polyol mixture, 0.5 to 4% by weight of the tertiary amine catalyst, The coated fertilizer granule composition according to claim 1, comprising 56 to 79.5% by weight of the polymethylene polyphenyl isocyanate mixture, wherein the total weight percentages of the polyol mixture, the tertiary amine catalyst, and the polymethylene polyphenyl isocyanate mixture are 100% by weight.

6. The coating concentration of the first layer is 0.9 to 1.1% by weight based on the total weight of the coated fertilizer granule composition. The coating concentration of the second layer is 0.9 to 1.1% by weight based on the total weight of the coated fertilizer granule composition, and the total coating concentration on the fertilizer granules is 1.8 to 2.2% by weight based on the total weight of the coated fertilizer granule composition. The reacting mixture is Based on the total weight of the reaction mixture, 25 to 30% by weight of the polyol mixture and the polyol mixture 48 to 52% by weight of the 1,4-butanediol; 48 to 52% by weight of the aforementioned trifunctional poly(propylene oxide), Homopolymer polyether polyol having an equivalent weight of 900-1100 g / eq It consists of, and the weight % is based on the total weight of the polyol mixture, Based on the total weight of the reaction mixture, 2.9 to 3.1% by weight of a tertiary amine catalyst, The coated fertilizer granule composition according to claim 1, comprising 65 to 75% by weight of the polymethylene polyphenyl isocyanate mixture based on the total weight of the reaction mixture, wherein the polymethylene polyphenyl isocyanate mixture consists of 13 to 15% by weight of ortho-paramethylene diphenyl diisocyanate based on the total weight of the polymethylene polyphenyl isocyanate mixture.

7. The coated fertilizer granule composition according to claim 1, wherein the coating density of the first polyurethane layer is 1.0 to 1.35% by weight based on the total weight of the coated fertilizer granule composition, and the coating density of the second polyurethane layer is 1.0 to 1.35% by weight based on the total weight of the coated fertilizer granule composition, and the total coating density on the fertilizer granules is 2.0 to 2.7% by weight based on the total weight of the coated fertilizer granule composition.

8. The coated fertilizer granule composition according to claim 1, further comprising a wax layer that at least partially coats the second polyurethane layer to provide a wax layer concentration of 0.5 to 1.0% by weight based on the total weight of the coated fertilizer granule composition.

9. The coating concentration of the first layer is 1% by weight based on the total weight of the coated fertilizer granule composition. The coating concentration of the second layer is 1% by weight based on the coated fertilizer granule composition, and the total coating concentration on the fertilizer granules is 2% by weight based on the total weight of the coated fertilizer granule composition. The reacting mixture is Based on the total weight of the reaction mixture, 27.4% by weight of the polyol mixture and the polyol mixture 50% by weight of the 1,4-butanediol; 50% by weight of the aforementioned trifunctional poly(propylene oxide), Homopolymer polyether polyol having an equivalent weight of 900-1100 g / eq It consists of, and the weight % is based on the total weight of the polyol mixture, Based on the total weight of the reaction mixture, 3.05% by weight of the tertiary amine catalyst and The reaction mixture comprises 69.55% by weight of the polymethylene polyphenyl isocyanate mixture based on the total weight of the reaction mixture, wherein the polymethylene polyphenyl isocyanate mixture consists of 14% by weight of the ortho-paramethylene diphenyl diisocyanate based on the total weight of the polymethylene polyphenyl isocyanate mixture. The coated fertilizer granule composition according to claim 1, further comprising a wax layer that at least partially covers the second polyurethane layer, and which provides a wax layer concentration of 0.5% by weight based on the total weight of the coated fertilizer granule composition.

10. The coated fertilizer granule composition according to any one of claims 8 to 9, wherein the wax layer comprises a polyolefin wax layer having 20 to 40 carbon atoms and a dropping point of 60 to 70 degrees Celsius (°C) as measured according to ASTM D3954.

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