Additive for the production of stabilized urea particles and its use

Abstract

The invention relates to a particulate composition comprising, or substantially consisting of, urea, an inhibitor, preferably a urease inhibitor and / or a nitrification inhibitor, and an additive, wherein the additive comprises components (i), (ii), and optionally (iii): (i) one or more polyhydric alcohols; preferably one or more carbohydrates, preferably selected from monosaccharides, disaccharides, and oligosaccharides; (ii) a first polymer, preferably an amine-containing polymer; more preferably a polyvinylamine or a polyalkyleneimine; and (ii) optionally, a second polymer, preferably a polar polymer; more preferably a water-soluble polar polymer. The invention further relates to a process for producing the particulate composition, an additive for a particulate composition, and the use of the particulate composition as a fertilizer.

Description

[0001] The invention relates to a particulate composition (urea particles) comprising, or substantially consisting of, urea, an inhibitor, preferably a urease inhibitor and / or a nitrification inhibitor, and an additive, wherein the additive comprises components (i), (ii), and optionally (iii): (i) one or more polyhydric alcohols; preferably one or more carbohydrates, preferably selected from monosaccharides, disaccharides, and oligosaccharides; (ii) a first polymer, preferably an amine-containing polymer; more preferably a polyvinylamine or a polyalkyleneimine; and (iii) optionally, a second polymer, preferably a polar polymer; more preferably a water-soluble polar polymer. The invention further relates to a process for producing the particulate composition, an additive for a particulate composition, and the use of the particulate composition as a fertilizer.

[0002] In conventional methods for producing urea particles, such as granulation or prilling, formaldehyde-based additives, such as urea-formaldehyde solutions, are typically added to the urea melt / solution before solidification. These additives are needed to improve granulation or prilling and thus the quality of the urea particles.

[0003] Due to new regulations requiring higher nitrogen use efficiency (NUE) and a reduction in ammonia and greenhouse gas emissions, the demand for stabilized urea is increasing and will be much higher in the future.

[0004] To produce stabilized urea, certain active ingredients must be added to the urea, particularly urease inhibitors, usually in the form of an inhibitor formulation. The most commonly used class of urease inhibitors are thiophosphoric triamides. Examples of commercially available thiophosphoric triamides are N-(n-butyl)thiophosphoric triamide (NBPT) and N-(n-propyl)thiophosphoric triamide (NPPT). Nitrification inhibitors are also frequently used.

[0005] Nowadays, urea particles are primarily treated with inhibitor formulations by wholesalers, in small quantities, in a separate treatment process at mixing stations / systems. In this process, the urea particles are coated with the inhibitor formulations. After application, inhibitors such as thiophosphoric triamides are relatively stable at a storage temperature of 20°C and show degradation rates of 10-50% of the initially present inhibitor after one year of storage.

[0006] For the nitrogen utilization efficiency of stabilized urea, a minimum concentration of the inhibitor in the urea particles must be ensured at the time of application in the field. In most regions, the potential to reduce nitrogen losses must be demonstrated / verified.

[0007] For treating large quantities of urea with inhibitors, it is more economical to perform the treatment upstream in the value chain, directly during granulation or prilling. For example, the urea can be treated with an inhibitor formulation as a melt / solution before entering the granulator / prilling tower, during the granulation process, or during cooling.

[0008] However, at a storage temperature of 20°C, an unexpectedly strong degradation of the inhibitor was observed, particularly of thiophosphoric triamides, when the urea particles are treated directly with the inhibitor during granulation or prilling, as described above.

[0009] This observed rapid degradation means that the required minimum concentration of the inhibitor in the treated urea product cannot be achieved economically or practically with this method at the time of application in the field. The stabilized urea product would have to be applied immediately after its production, i.e., without intermediate storage, which is logistically impossible. Alternatively, the inhibitor would have to be added in a very high concentration, which is unacceptable from both an economic and environmental perspective.

[0010] WO 2015 027244 A1 relates to a urea-nitrogen stabilizer composition and to methods, systems, and equipment for its production. The composition is incorporated into molten urea to obtain a composition containing less biuret, N-methyl-2-pyrrolidone (NMP), nitrogen stabilizer, and / or impurities, and yielding an effective solid fertilizer. These compositions are useful for odor control.

[0011] WO 2016 137815 A1 relates to a urea granulate with a nitrogen stabilizer and a carrier system that is essentially homogeneously distributed over the entire granule thickness. Various processes for the production of urea granulate are described, including pricking, fluidized bed, and drum granulation. The nitrogen stabilizer may contain a urease inhibitor such as NBPT, with the NBPT purity ranging from 90% to 99%. The nitrogen stabilizer may also contain a nitrification inhibitor such as dicyandiamide (DCD).

[0012] WO 2019 197183 A1 relates to a process for the production of a fertilizer composition comprising at least one urea-containing fertilizer and at least one (thio)phosphoric triamide.

[0013] WO 2022 136360 A2 relates to a process for producing a homogeneous, solid, particulate, urea-based composition comprising urea and one or more additives in a urea production plant.

[0014] WO 2002 020471 A2 relates to a method for improving the compressive strength and impact strength of urea granules by adding an additive comprising a polyvinyl compound of the general formula (CHX-CHY) n The process comprises a group of molecules, where n = 4–10,000 and X and Y are independently selected from the group consisting of a hydrogen atom, a hydroxyl group, a carboxylic acid group, an amine group, or an amide group. This process is characterized by the fact that it begins with a urea melt.

[0015] US 10,752,559 B2 relates to a particulate urea-containing composition and the use of an additive for the manufacture of a particulate urea-containing composition and a process for the manufacture of a particulate urea-containing composition.

[0016] US 7,816,561 B2 relates to a method for improving compressive strength and reducing dust formation and the tendency of urea particles to clump together by adding an organic compound to the molten urea, wherein at least one carbohydrate and optionally a polyvinyl compound is added to the urea, and a composition intended to be used as a urea additive.

[0017] US 8,084,642 B2 relates to a method for improving the compressive strength, impact strength and compressibility of urea granules by adding a compound to the molten urea, wherein the compound comprises both a polyvinyl compound and an organic molecule consisting of 1 to 10 carbon atoms and 1 to 10 polar organic groups.

[0018] EP 3 157 889 B1 relates to a particulate urea-containing composition, a process and apparatus for its production, its use as a fertilizer, as technical urea or feed additive, and the use of an additive for the production of a particulate urea-containing composition. The particulate composition contains (i) urea; and an additive comprising one or both of the following components: (ii) and (iii): (ii) a combination of at least one polymer or oligomer containing amino groups and at least one functionalized polyvinyl compound; (iii) at least one aliphatic C2-C8 dialdehyde; wherein the weight fraction of component (i) is > 60 wt.% and the weight fraction of the sum of components (ii) and (iii) in the composition is < 1 wt.%.The additive may also comprise a component (iv): (iv) at least one compound selected from the group consisting of aliphatic dicarboxylic acids, their salts and anhydrides, aliphatic tricarboxylic acids, their salts and anhydrides, aromatic dicarboxylic acids, their salts and anhydrides, and aldehydic acids, their salts and anhydrides, wherein the weight fraction of component (i) is > 60 wt.% and the weight fraction of the sum of components (ii), (iii) and (iv) in the composition is < 1 wt.%.

[0019] EP 3 484 601 B1 relates to a process for producing a NOx reducing agent AUS 32 solution (Diesel Exhaust Fluid) comprising at least the mixing of water and a particulate composition containing (i) urea; and an additive comprising component (ii): (ii) a combination of at least one polymer or oligomer containing amino groups and at least one functionalized polyvinyl compound; wherein the weight fraction of component (i) in the particulate composition is > 60 wt.% and the weight fraction of component (ii) in the particulate composition is < 1 wt.% and wherein a urea solution is obtained and the weight fraction of component (i) in the obtained urea solution is between 31 wt.% and 34 wt.%.

[0020] EP 3 380 446 B1 relates to a particulate composition containing (i) urea; and an additive comprising one or both of the components (ii) and (iii): (ii) a combination of at least one polymer or oligomer containing amino groups and at least one functionalized polyvinyl compound; (iii) at least one aliphatic C2-C8 dialdehyde; and an additive comprising one or more of the components (iv) to (vi): (iv) sulfur; (v) ammonium sulfate; (vi) at least one trace element; wherein the weight fraction of component (i) is > 10 wt.% and the weight fraction of the sum of components (ii) and (iii) in the composition is < 1 wt.%, the use of this additive for the production of the particulate, urea-containing composition, the process and apparatus for producing the composition, and its use as a fertilizer.

[0021] The known urea particles are not satisfactory in every respect and there is a need for improvements, especially with regard to storage stability.

[0022] It is an object of the invention to provide urea particles containing additives other than formaldehyde-based additives, as well as urease inhibitors, in particular thiophosphoric triamides, and / or nitrification inhibitors, and which are characterized by improved storage stability, particularly with regard to the inhibitor content. The urea particles should be easy and inexpensive to produce.

[0023] This problem is solved by the subject matter of the patent claims.

[0024] It was surprisingly found that the degradation of the inhibitor, particularly thiophosphoric triamides, can be significantly reduced, i.e., storage stability can be significantly improved, when an additive with low reactivity towards the inhibitor is used as a replacement for a formaldehyde-based additive. Additives that are neither acidic nor acid-forming are particularly suitable.

[0025] Furthermore, it was surprisingly found that an additive combining a polyhydric alcohol, in particular one or more carbohydrates such as high-fructose corn syrup (HFCS), invert sugar syrup, or even honey, with a first polymer, preferably an amine-containing polymer, in particular polyethyleneimine or polyvinylamine, and optionally a second polymer, preferably a polar polymer, in particular polyvinyl alcohol, is particularly suitable as an additive. If such an additive is added as an aqueous solution to a urea melt and / or urea solution prior to granulation / prilling, urea particles can be obtained that meet the usual quality criteria and exhibit improved storage stability (inhibitor degradation rate). Urea particles containing such an additive and an inhibitor, preferably a thiophosphoric triamide such as...Samples treated with N-(n-butyl)thiophosphoric triamide (NBPT) or N-(n-propyl)thiophosphoric triamide (NPPT), or with inhibitor formulations containing these inhibitors, either during or after granulation / pricking, exhibited satisfactorily low inhibitor degradation rates.

[0026] A first aspect of the invention relates to a particulate composition comprising or substantially consisting of urea, an inhibitor, preferably a urease inhibitor and / or a nitrification inhibitor, and an additive, wherein the additive comprises components (i), (ii) and optionally (iii): (i) one or more polyhydric alcohols; preferably one or more carbohydrates, preferably selected from monosaccharides, disaccharides, and oligosaccharides; (ii) a first polymer, preferably an amine-group-containing polymer; more preferably a polyvinylamine or a polyalkylenemine; and (iii) optionally, a second polymer, preferably a polar polymer; more preferably a water-soluble polar polymer.

[0027] For descriptive purposes, "essentially consisting of" means that the presence of other components in the mixture is not excluded, provided they do not significantly alter essential characteristics of the mixture. Preferably, "essentially consisting of" means that the expressly listed components / ingredients of the mixture constitute at least 95% by weight of the mixture, more preferably at least 96% by weight, more preferably at least 97% by weight, most preferably at least 98% by weight, and particularly at least 99% by weight.

[0028] For descriptive purposes, "particulate" means a physical form which can also be described as granulated, prilled, crystalline, compacted, pulverized, and the like, wherein the "particulate" composition exists as a composition in a small, uniform form (particles) as a multitude of small, solid particles, i.e., particles whose dimensions are small compared to the scale of the particulate substance as a whole (i.e., as granules, prills, crystallites, pellets, powder, or pulverized material). Preferably, the particulate composition exists as granules, i.e., as a granular substance ("granular matter"). For descriptive purposes, a "granule" consists of many individual, small, solid particles such as grains. Preferably, each grain comprises seed, e.g., recycled undersize material, and urea sprayed onto the seed.

[0029] Preferably the mean particle size (D50 (mass-averaged)) of the particulate composition is in the range of 0.5 mm to 5.0 cm; preferably 1.0 mm to 1.0 cm, more preferably 1.0 mm to 6.0 mm, even more preferably 2.0 mm to 5.0 mm, and most preferably 2.0 mm to 4.0 mm; preferably determined by sieve analysis according to DIN EN 1235:2003-08.

[0030] The particulate composition according to the invention comprises urea.

[0031] Preferably the urea content is at least 50 wt.%; preferably at least 60 wt.%, more preferably at least 70 wt.%, even more preferably at least 80 wt.%, most preferably at least 90 wt.%, and in particular at least 95 wt.%; in each case relative to the total weight of the particulate composition.

[0032] The particulate composition according to the invention further comprises an inhibitor, preferably a urease inhibitor and / or a nitrification inhibitor.

[0033] The urease inhibitor is preferably selected from the group consisting of N-(n-butyl)thiophosphoric triamide (NBPT), N-(n-propyl)thiophosphoric triamide (NPPT), hydroquinone, phosphorus triamide, p-benzoquinone, cyclohexyl phosphate triamide, and hexaamidocyclotriphosphazene; preferably N-(n-butyl)thiophosphoric triamide and N-(n-propyl)thiophosphoric triamide.

[0034] The nitrification inhibitor is preferably selected from the group consisting of dicyandiamide, 1-methylpyrazole-1-hydroxyamide, 3-methylpyrazole, ethylene urea, chlorazole, 4-aminotriazole, thiourea, acetylene, 2-ethinylpyridine, sulfathiazole, amidinothiourea, 1-amino-2,4-dimethylpyrazole phosphate, thiosulfates, for example sodium thiosulfate, calcium carbide, 2,5-chloroaniline, 3-acetanilide, toluene, carbon disulfide, phenylacetylene, 2-propyn-1-ol and phenethylphosphonium diamide.

[0035] The particle-shaped composition according to the invention preferably comprises a urease inhibitor; preferably a thiophosphoric triamide; preferably N-(n-butyl)thiophosphoric triamide (NBPT) and / or N-(n-propyl)thiophosphoric triamide (NPPT).

[0036] The composition may also contain several urease inhibitors and / or several nitrification inhibitors. A composition with at least one urease inhibitor (or with several urease inhibitors) and additionally at least one nitrification inhibitor (or with several nitrification inhibitors) is therefore preferred.

[0037] In preferred embodiments, the particulate composition comprises two urease inhibitors; preferably two thiophosphoric triamides; preferably N-(n-butyl)thiophosphoric triamide (NBPT) and N-(n-propyl)thiophosphoric triamide (NPPT).

[0038] In preferred embodiments, the inhibitor content is at most 1.0 wt.%; preferably at most 0.5 wt.%, more preferably at most 0.1 wt.%, and even more preferably at most 0.05 wt.%; in each case based on the sum of all inhibitors contained in the particulate composition and relative to the total weight of the particulate composition.

[0039] In preferred embodiments, the inhibitor content is in the range of 0.005 to 0.5 wt.%; preferably 0.01 to 0.1 wt.%, more preferably 0.02 to 0.08 wt.%, and even more preferably 0.04 to 0.06 wt.%; in each case based on the sum of all inhibitors contained in the particulate composition and relative to the total weight of the particulate composition.

[0040] Preferably, the particulate composition contains no solvent and no stabilizer for the inhibitor (or at most unavoidable residual amounts thereof). Alternatively, the particulate composition according to the invention can also contain at least some of the solvent and / or the stabilizer for the inhibitor.

[0041] The particulate composition according to the invention comprises an additive, wherein the additive comprises components (i), (ii) and optionally (iii): (i) one or more polyhydric alcohols; preferably one or more carbohydrates, preferably selected from monosaccharides, disaccharides, and oligosaccharides; (ii) a first polymer, preferably an amine-group-containing polymer; more preferably a polyvinylamine or a polyalkylenemine; and (iii) optionally, a second polymer, preferably a polar polymer; more preferably a water-soluble polar polymer.

[0042] For the purposes of description, an "additive" is a composition that can advantageously be added to (conventional) fertilizers to improve their properties. A fertilizer additive is generally not a fertilizer as such. The primary function of the additive according to the invention is preferably to improve the production, storage properties, and application of the inhibitor-treated fertilizer or fertilizer granules, in particular the granulation behavior and product quality (crushing strength, caking, and bulk density) of the granules.

[0043] The particulate composition according to the invention comprises urea, the inhibitor, and components (i), (ii), and optionally (iii) of the additive. For the purposes of description, the individual components (i), (ii), and optionally (iii) of the additive can be added together or separately during the preparation of the particulate composition. For example, one of the components (i), (ii), and optionally (iii) can be added separately to the urea or the inhibitor.

[0044] Preferably, the additive does not react with thiophosphoric triamides, thereby degrading or otherwise reducing the activity of the inhibitor. Preferably, the additive has a stabilizing effect on the inhibitor.

[0045] Preferably, the additive is in the form of a solid, a liquid or a suspension; preferably as a solution.

[0046] Preferably, the additive is a mixture of water-soluble substances; more preferably, an aqueous solution. In particularly preferred embodiments, the additive is an aqueous solution comprising (i) isoglucose, preferably high fructose corn syrup (HFCS), invert sugar syrup, or honey, (ii) polyvinylamine or polyethyleneimine, and optionally (iii) polyvinyl alcohol.

[0047] In preferred embodiments, the additive also contains urea.

[0048] The additive according to the invention comprises one or more polyhydric alcohols; preferably one or more carbohydrates.

[0049] For descriptive purposes, "polyhydric alcohols" are organic compounds containing two or more alcoholic hydroxyl groups (-OH). Examples of "polyhydric alcohols" include polyols, carbohydrates such as monosaccharides, disaccharides, and oligosaccharides, as well as diols and triols, for example, ethanediol, propanediol, butanediol, pentanediol, hexanediol, decanediol, benzyldimethanol, and propanetriol.

[0050] Preferably, the one or more polyhydric alcohols are selected independently from monosaccharides, disaccharides and oligosaccharides; preferably monosaccharides; particularly preferably glucose and fructose or mixtures of the aforementioned, in particular mixtures of glucose and fructose.

[0051] Preferably, component (i) comprises two or more polyhydric alcohols; preferably glucose and fructose; preferably isoglucose or invert sugar; more preferably high fructose corn syrup (HFCS) or invert sugar syrup.

[0052] For the purposes of description, "high fructose corn syrup" (HFCS) is a glucose-fructose syrup (isoglucose syrup), which is an aqueous solution of isoglucose (isomeric sugar), a mixture of fructose and glucose. In corn syrup, the isoglucose can be obtained enzymatically from glucose by converting a portion of the glucose into fructose (typically by glucose isomerase), the glucose having previously been obtained from cornstarch by (enzymatic) hydrolysis. Preferably, corn syrup contains, in addition to fructose and glucose, small amounts of other polyhydric alcohols, particularly disaccharides such as maltose and sucrose.

[0053] Furthermore, for descriptive purposes, "invert sugar syrup" is also a glucose-fructose syrup, but it is an aqueous solution of invert sugar (invertose), a mixture of fructose and glucose, which can be obtained in particular by hydrolysis (typically catalytic, especially enzymatic) of table sugar (sucrose).

[0054] Surprisingly, it was found that different polyhydric alcohols have different effects on granulation / pricking, with corn syrup and invert sugar syrup being particularly beneficial.

[0055] Preferably, the one polyhydric alcohol or the several polyhydric alcohols have a molecular weight of at most 3000 g / mol; preferably at most 2600 g / mol, more preferably at most 2200 g / mol, even more preferably at most 1800 g / mol, most preferably at most 1400 g / mol, and in particular at most 1000 g / mol.

[0056] Preferably, one or more polyhydric alcohols are water-soluble.

[0057] For the purpose of describing polyhydric alcohols, "water-soluble" means that at room temperature (20°C) an aqueous solution of the polyhydric alcohol is present which contains at least 1 g / L of the polyhydric alcohol.

[0058] Preferably, one or more polyhydric alcohols have a pK A -value of at least 7.5; preferably at least 8.0, more preferably at least 9.0, even more preferably at least 10, most preferably at least 11, and in particular at least 12.

[0059] In preferred embodiments, the total content of the one polyhydric alcohol or the several polyhydric alcohols is in the range of 0.001 to 1.5 wt.%, preferably 0.002 to 1.0 wt.%; preferably 0.004 to 0.8 wt.%, more preferably 0.006 to 0.6 wt.%, even more preferably 0.008 to 0.4 wt.%, and most preferably 0.01 to 0.2 wt.%; in each case relative to the total weight of the particulate composition.

[0060] The additive according to the invention comprises a first polymer, preferably a polymer containing amine groups.

[0061] Preferably, the first polymer is selected from polyamines, polyalkylenemines, preferably polyethyleneimines and polypropyleneimines, polyvinylamines, polyalkoxylated polyamines, ethoxylated polyamines, propoxylated polyamines, and alkylated and / or benzylated polyamines; preferably polyamines, polyalkylenemines, preferably polyethyleneimines and polypropyleneimines, and polyvinylamines; preferably polyalkylenemines, preferably polyethyleneimines and polypropyleneimines, and polyvinylamines.

[0062] Preferably, the first polymer, preferably the polymers containing amino groups, can have a nitrogen content of 10 to 50 wt.%, based on the weight of the polymer, and contain primary, secondary or tertiary amino groups which independently contain alkyl or arylalkyl groups, for example C 1-6 -Alkyl or aryl-C 1-\3-Alkyl, where aryl can in particular stand for phenyl or pyridyl, which is unsubstituted or optionally with 1, 2, 3, 4 or 5 substituents independently selected from the group consisting of F, Cl, Br, CF3, C 1-6 -Alkyl, C 1-6 -Alkoxy, NH2, C 1-6 -Alkylamino and Di(C 1-6 -Alkyl)amino may be substituted.

[0063] Preferably, the first polymer is a polyethyleneimine and / or a polyvinylamine.

[0064] Preferably, the first polymer has a molecular weight in the range of 200 to 2,000,000 g / mol; preferably 400 to 1,000,000 g / mol, more preferably 600 to 500,000 g / mol, even more preferably 800 to 250,000 g / mol, most preferably 1000 to 100,000 g / mol, and particularly 1200 to 10,000 g / mol.

[0065] In preferred embodiments, the first polymer is a polyethyleneimine and has a molecular weight in the range of 500 to 2,000,000 g / mol.

[0066] In other preferred embodiments, the first polymer is a polyvinylamine and has a molecular weight in the range of 500 to 1,000,000 g / mol.

[0067] Preferably, the first polymer is water-soluble.

[0068] The first polymer is preferably polar.

[0069] For the purpose of describing the first polymer, "water-soluble" means that at room temperature (20°C) an aqueous solution of the first polymer is present which contains at least 1 g / L of the first polymer.

[0070] For descriptive purposes, "polar polymer" means a polymer with a polar group. The polar group refers to a functional group that forms a dipole with an uneven center of positive and negative charge due to a distorted distribution of electron clouds resulting from a difference in the electronegativity of the atoms that make up the functional group. Examples of polar groups include an ether group, a carboxyl group, a sulfone group, a phosphate group, a formyl group, an amino group, an amide group, a hydroxyl group, a cyano group, an epoxy group, an ester group, a carbonate group, and a lactone group.Examples of polar polymers include polyethers, polyacrylonitrile, polyvinyl carbonate, polycarbonate, polyester, and polymethyl methacrylate, each containing an ether bond in a repeating unit, or polyvinyl alcohols, each containing a hydroxyl group in a repeating unit. A polar polymer typically has a dipole moment greater than 0 D at 25°C.

[0071] In preferred embodiments, the total content of the first polymer is in the range of 0.002 to 2.0 wt.%; preferably 0.004 to 1.5 wt.%, more preferably 0.006 to 1.0 wt.%, even more preferably 0.008 to 0.75 wt.%, and most preferably 0.01 to 0.5 wt.%; in each case relative to the total weight of the particulate composition.

[0072] The additive according to the invention optionally comprises a second polymer, preferably a polar polymer.

[0073] The additive according to the invention comprises (ii) the first polymer, which is preferably an amine-group-containing polymer; and (iii) optionally, the second polymer, which is preferably a polar polymer; where the first polymer is different from the second polymer.

[0074] Preferably, the second polymer is an organic polymer.

[0075] Preferably the second polymer is a vinyl polymer, a polyester, a polyether, or a polyacrylate; preferably a vinyl polymer, a polyester, or a polyether.

[0076] For the purposes of description, "vinyl polymer" also includes functionalized polyvinyl compounds. According to the invention, functionalized polyvinyl compounds include, in particular, compounds based on the repeating unit (CHX-CHY). nconsidering, wherein X is selected from the group consisting of H, OH, COOH, COR, CH2OH and CH2OR and Y is selected from the group consisting of OH, COOH, COR, CH2OH and CH2OR and wherein R is each independently for alkyl, in particular C 1-6 -Alkyl, or aryl, in particular phenyl or pyridyl, which can stand unsubstituted or optionally with 1, 2, 3, 4 or 5 substituents independently selected from the group consisting of F, Cl, Br, CF3, C 1-6 -Alkyl, C 1-6 -Alkoxy, may be substituted.

[0077] Preferably, the second polymer does not contain any amine groups.

[0078] Preferably the second polymer is selected from the group consisting of polyvinyl alcohol (PVOH), polyethylene glycol (PEG), polylactic acid (PLA), polyethylene glycol esters, butenediol-vinyl alcohol copolymer (BVOH), polyvinylpyrrolidone (PVP), and polyacrylamide (PAM); preferably polyvinyl alcohol (PVOH), polyethylene glycol (PEG), polylactic acid (PLA), and polyethylene glycol esters; preferably polyvinyl alcohol (PVOH).

[0079] Preferably, the second polymer has a molecular weight in the range of 200 to 2,000,000 g / mol; preferably 400 to 1,000,000 g / mol, more preferably 600 to 500,000 g / mol, even more preferably 800 to 250,000 g / mol, most preferably 1000 to 100,000 g / mol, and particularly 1200 to 10,000 g / mol.

[0080] Preferably, the second polymer is water-soluble.

[0081] For the purpose of describing the second polymer, "water-soluble" means that at room temperature (20°C) an aqueous solution of the second polymer is present which contains at least 1 g / L of the second polymer.

[0082] Preferably, the second polymer is biodegradable.

[0083] For the purpose of describing the second polymer, “biodegradable” means that at least 60 wt% of the second polymer is biodegradable, in particular by a process in accordance with OECD 301 A or B, preferably within 28 days and at a concentration of 10 to 40 mg DOC / L (DOC = “dissolved organic carbon”).

[0084] Preferably, the second polymer is not harmful to the environment.

[0085] Preferably, the particulate composition according to the invention is not acidic with respect to its pH value. Preferably, the pH value of an aqueous solution of the particulate composition (including the second polymer) with a particulate composition content of 10 wt% immediately after dissolution does not fall below a pH value of 7.0. Preferably, the pH value of an aqueous solution of the particulate composition (including the second polymer) with a particulate composition content of 10 wt% immediately after dissolution is at least 8.0; more preferably in the range of 8.0 to 10. Preferably, the particulate composition does not comprise any acidic components.

[0086] Preferably, the second polymer is non-acidic.

[0087] Preferably, an aqueous solution of the second polymer with a content of 5.0 wt% of the second polymer has a pH value of at least 5.0 immediately after dissolution, more preferably in the range of 5.0 to 6.5.

[0088] Preferably, the second polymer has a pKa value of at least 7.0, preferably at least 10.0, and particularly preferably at least 12.

[0089] In preferred embodiments, the total content of the second polymer is in the range of 0.002 to 1.0 wt.%; preferably 0.004 to 0.8 wt.%, more preferably 0.006 to 0.6 wt.%, even more preferably 0.008 to 0.4 wt.%, and most preferably 0.01 to 0.2 wt.%; in each case relative to the total weight of the particulate composition.

[0090] Preferably the second polymer is not a polyamide, i.e. preferably not a linear polymer with regularly repeating amide bonds along the main chain; more preferably not a urea resin.

[0091] Preferably, the one or more polyhydric alcohols, the first polymer and the optional second polymer are different from each other, i.e., the additive according to the invention preferably comprises at least two different compounds and optionally a further third compound.

[0092] In preferred embodiments, the total additive content, i.e., components (i), (ii) and optionally (iii), is at least 0.02 wt.%; preferably at least 0.04 wt.%, more preferably at least 0.06 wt.%, more preferably at least 0.08 wt.%, and most preferably at least 0.1 wt.%; in each case relative to the urea content in the particulate composition.

[0093] In preferred embodiments, the total additive content, i.e., components (i), (ii) and optionally (iii), is at most 1.5 wt.%, preferably at most 1.0 wt.%; preferably at most 0.8 wt.%, more preferably at most 0.6 wt.%, more preferably at most 0.4 wt.%, and most preferably at most 0.2 wt.%; in each case relative to the urea content in the particulate composition.

[0094] In preferred embodiments, the total additive content, i.e., components (i), (ii) and optionally (iii), is in the range of 0.12 ± 0.1 wt.%; preferably 0.12 ± 0.08 wt.%, more preferably 0.12 ± 0.06 wt.%, even more preferably 0.12 ± 0.04 wt.%, and most preferably 0.12 ± 0.02 wt.%; in each case relative to the urea content in the particulate composition.

[0095] In preferred embodiments, the total additive content, i.e., components (i), (ii) and optionally (iii), is at least 0.02 wt.%; preferably at least 0.04 wt.%, more preferably at least 0.06 wt.%, more preferably at least 0.08 wt.%, and most preferably at least 0.1 wt.%; in each case relative to the total weight of the particulate composition.

[0096] In preferred embodiments, the total additive content, i.e., components (i), (ii) and optionally (iii), is at most 1.5 wt.%, preferably at most 1.0 wt.%; preferably at most 0.8 wt.%, more preferably at most 0.6 wt.%, more preferably at most 0.4 wt.%, and most preferably at most 0.2 wt.%; in each case relative to the total weight of the particulate composition.

[0097] In preferred embodiments, the total additive content, i.e., components (i), (ii) and optionally (iii), is in the range of 0.12 ± 0.1 wt.%; preferably 0.12 ± 0.08 wt.%, more preferably 0.12 ± 0.06 wt.%, even more preferably 0.12 ± 0.04 wt.%, and most preferably 0.12 ± 0.02 wt.%; in each case relative to the total weight of the particulate composition.

[0098] In preferred embodiments, the relative weight ratio of component (i) to component (ii) is in the ratio of 10:1 to 1:10, preferably 8:1 to 1:8, more preferably 6:1 to 1:6, even more preferably 4:1 to 1:4, most preferably 3:1 to 1:3 and in particular 2:1 to 1:2.

[0099] In preferred embodiments, the relative weight ratio of component (i) to optional component (iii) is in the ratio of 10:1 to 1:10, preferably 8:1 to 1:8, more preferably 6:1 to 1:6, even more preferably 4:1 to 1:4, most preferably 3:1 to 1:3 and in particular 2:1 to 1:2.

[0100] In preferred embodiments, the relative weight ratio of component (ii) to optional component (iii) is in the ratio of 10:1 to 1:10, preferably 8:1 to 1:8, more preferably 6:1 to 1:6, even more preferably 4:1 to 1:4, most preferably 3:1 to 1:3 and in particular 2:1 to 1:2.

[0101] In preferred embodiments, the total content of additive, i.e. components (i), (ii) and (iii), and inhibitor is at most 1.5 wt.%, preferably at most 1.0 wt.%; preferably at most 0.8 wt.%, more preferably at most 0.6 wt.%, more preferably at most 0.4 wt.%, and most preferably at most 0.2 wt.%; in each case relative to the content of urea in the particulate composition.

[0102] In preferred embodiments, the particulate composition according to the invention comprises one or more additives; preferably the additives contain one or more of the following components: - Sulfur; - Ammonium sulfate; - at least one trace element.

[0103] The additive can comprise either (elemental) sulfur or ammonium sulfate, or at least one trace element. Likewise, the additive can comprise any possible combination of the aforementioned components or may also contain other constituents. The sulfur can be used in its elemental form or as a component of a compound. For example, the additive can comprise sulfur in the form of sulfates. Trace elements are preferably those elements that are necessary for a living organism and are typically present in organisms in mass fractions of less than 50 mg / kg. Trace elements can include, for example, aluminum, boron, chlorine, iron, copper, manganese, molybdenum, and / or zinc. A person skilled in the art recognizes that the term trace element encompasses both a single element and any possible mixture of two or more elements.

[0104] In preferred embodiments, the particulate composition according to the invention comprises ammonium sulfate.

[0105] Preferably, the ammonium sulfate content is at most 1.0 wt.%; preferably at most 0.75 wt.%, more preferably at most 0.5 wt.%, and even more preferably at most 0.3 wt.%; in each case relative to the total weight of the particulate composition.

[0106] The particulate composition according to the invention may contain further components in addition to those already mentioned. For example, the particulate composition according to the invention may contain water, e.g., in an amount of 0.05 to 0.5 wt.%, in particular 0.1 to 0.3 wt.%, and byproducts of urea synthesis such as biuret or NH3, or antifoaming agents such as mono- and diglycerides of fatty acids and dimethylpolysiloxane. Typically, the proportion of byproducts does not exceed 1.5 wt.%, in particular not more than 1.25 wt.%.

[0107] Another aspect of the invention relates to an additive as described above comprising components (i), (ii) and optionally (iii) for producing a particulate composition as described above.

[0108] Another aspect of the invention relates to the use of an additive as described above for the production of a particulate composition as described above.

[0109] Another aspect of the invention relates to a method for producing a particulate composition as described above, wherein the method comprises the steps: (a) Providing an inhibitor composition containing an inhibitor, preferably a urease inhibitor and / or a nitrification inhibitor; (b) Providing a urea-containing solution and / or melt; (c) Granulating or pricking the urea-containing solution and / or melt to obtain a particulate composition; (d) optional pre-cooling of the particulate composition; (e) optionally classifying the particulate composition to obtain particle fractions; (f) optionally separating a particle fraction obtained in step (e); and returning this separated particle fraction to a granulation or pricking unit used in step (c) (optionally after comminution of the particles of this particle fraction); and (g) optional post-cooling of the particulate composition; wherein component (i), component (ii), and optionally component (iii) of an additive as described above are added independently of one another; preferably to the provided inhibitor composition or to the urea-containing solution and / or melt; wherein the inhibitor composition is added to the urea-containing solution and / or melt or brought into contact with the particulate composition.

[0110] The inhibitor composition is preferred, (i) after step (c) and before step (d); (ii) during step (d); (iii) after step (d) and before step (e); (iv) during step (e); (v) after step (e) and before step (f); (vi) during step (f); (vii) after step (f) and before step (g); (viii) during step (g); and / or (ix) after step (g); brought into contact with the particulate composition.

[0111] In preferred embodiments, the inhibitor composition is added to the urea-containing solution and / or melt before or during step (c) of the process according to the invention.

[0112] In preferred embodiments, the inhibitor composition is added to the urea-containing solution and / or melt as a liquid or suspension, preferably as a solution.

[0113] Particularly pronounced advantages arise when granulation is carried out as fluidized bed granulation.

[0114] Preferably, the temperature of the urea-containing solution and / or melt is at least 120°C; preferably at least 125°C, and more preferably at least 130°C.

[0115] The inhibitor composition is preferably liquid, preferably a solution.

[0116] Typically, an inhibitor composition contains a solvent and a stabilizer for the inhibitor. However, the inhibitor composition can also contain the components in undissolved form. The particulate composition according to the invention can contain at least some of the solvent and / or the stabilizer for the inhibitor.

[0117] In preferred embodiments, the additive, i.e., components (i), (ii), and optionally (iii), is added to the urea-containing solution and / or melt before or during step (c) of the process according to the invention.

[0118] Preferably, the additive, i.e., components (i), (ii), and optionally (iii), is added in step (c) of the method according to the invention.

[0119] Preferably, the additive is added in step (c) to the urea-containing solution and / or melt; preferably before the urea-containing solution and / or melt solidifies.

[0120] The additive is preferably added as a solid, liquid or suspension, preferably before or during step (c); preferably as a solution; more preferably as an aqueous solution.

[0121] In preferred embodiments, the additive also contains urea.

[0122] The additive is preferably added as an aqueous solution or aqueous suspension, preferably before or during step (c); more preferably as a urea-containing aqueous solution.

[0123] Alternatively, the additive can also be added to a urea melt or urea solution as a solid.

[0124] In embodiments, the second polymer is added as a reactive monomer of the polymer, wherein the reactive monomer preferably polymerizes in situ, thereby forming the second polymer. Preferably, the monomer does not react with the inhibitor.

[0125] In preferred embodiments, the addition of component (i), component (ii) and / or optional component (iii) to the urea-containing solution and / or melt is carried out together in one step; preferably in a solution.

[0126] In other preferred embodiments, component (i), component (ii), and optional component (iii) are added sequentially to the urea-containing solution and / or melt. Preferably, component (i), component (ii), and optional component (iii) are added to the urea-containing solution and / or melt in separate solutions. Preferably, component (i), component (ii), and optional component (iii) are added to the urea-containing solution and / or melt sequentially. In preferred embodiments, components (i) and (ii), or components (i) and (iii), or components (ii) and (iii) are added in a common solution. In preferred embodiments, component (i) is added before components (ii) and (iii). In other preferred embodiments, component (ii) is added before components (i) and (iii).In further preferred embodiments, component (iii) is added before components (i) and (ii).

[0127] Preferably, the additive is added to the urea-containing solution and / or melt separately from the addition of the inhibitor composition to the urea-containing solution and / or melt.

[0128] Another aspect of the invention relates to the use of a particulate composition as described above as a fertilizer.

[0129] The following examples serve to illustrate the invention, but are not to be interpreted restrictively. Example 1:

[0130] A particulate composition comprising urea, an inhibitor, and an additive was prepared. To this end, high-fructose corn syrup (HFCS), an aqueous solution of polyethyleneimine, and an aqueous solution of polyvinyl alcohol were first added to a 97% urea solution, either manually or at a constant rate using a dosing pump. An inhibitor composition (Limus) was then added. ® BASF Direct (containing a combination of NPPT and NBPT) was added to the urea-containing melt either manually or at a constant rate via a metering pump. The resulting combined mixture of concentrated urea solution and additive was then fed into a fluidized bed granulator and granulated, forming the particulate composition. After three months of storage of the particulate composition, only minimal degradation of the inhibitor was observed. Example 2:

[0131] A particulate composition comprising urea, an inhibitor, and an additive was prepared. High fructose corn syrup (HFCS) and an aqueous solution of polyvinylamine were added to a 97% urea solution, either manually or at a constant rate using a dosing pump. An inhibitor composition (Limus) ® BASF Direct, containing a combination of NPPT and NBPT, was added to the urea-containing melt either manually or at a constant rate via a metering pump. The combined mixture was then fed into a granulator and granulated. After three months of storage of the particulate composition, only minimal degradation of the inhibitor was observed. Example 3:

[0132] A particulate composition comprising urea, an inhibitor, and an additive was prepared. High fructose corn syrup (HFCS), an aqueous solution of polyvinylamine, and an aqueous solution of polyvinyl alcohol were added to a 97% urea solution, either manually or at a constant rate via a dosing pump. An inhibitor composition (Limus) ® BASF Direct (containing a combination of NPPT and NBPT) was added to the urea-containing melt either manually or at a constant rate via a metering pump. The combined mixture was then fed into a granulator and granulated. After two months of storage of the particulate composition, only minimal degradation of the inhibitor was observed.

[0133] Fig.This figure shows the degradation of the inhibitor when using an additive according to Examples 1, 2, and 3, and when using urea-formaldehyde as the additive. It illustrates the decrease in the percentage of inhibitor content of the product over time, based on the amount present immediately after production, during storage. A decrease to approximately 20% was observed during storage of urea fertilizer granules with a conventional additive from a pilot plant over several months. A decrease to approximately 40% was observed during storage of urea fertilizer granules with a conventional additive from a commercial plant over several months. A decrease of less than 10% was observed during storage of urea fertilizer granules with three different additives according to the invention, as described in Examples 1, 2, and 3, from a pilot plant over several months. QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] WO 2015 027244 A1

[0010] WO 2016 137815 A1

[0011] WO 2019 197183 A1

[0012] WO 2022 136360 A2

[0013] WO 2002 020471 A2

[0014] US 10,752,559 B2

[0015] US 7,816,561 B2

[0016] US 8,084,642 B2

[0017] EP 3 157 889 B1

[0018] EP 3 484 601 B1

[0019] EP 3 380 446 B1

[0020] Cited non-patent literature

[0000] DIN EN 1235:2003-08

[0029]

Claims

[1] Particle composition comprising or substantially consisting of urea, an inhibitor, preferably a urease inhibitor and / or a nitrification inhibitor, and an additive, wherein the additive comprises the components (i), (ii) and optionally (iii): (i) one or more polyhydric alcohols; preferably one or more carbohydrates, preferably selected from monosaccharides, disaccharides, and oligosaccharides; (ii) a first polymer, preferably an amine-group-containing polymer; more preferably a polyvinylamine or a polyalkylenemine; and (iii) optionally, a second polymer, preferably a polar polymer; more preferably a water-soluble polar polymer. [2] The particulate composition according to claim 1, wherein the urea content is at least 50 wt.%; preferably at least 60 wt.%, more preferably at least 70 wt.%, more preferably at least 80 wt.%, most preferably at least 90 wt.%, and in particular at least 95 wt.%; in each case relative to the total weight of the particulate composition. [3] The particulate composition according to claim 1 or 2, comprising a urease inhibitor; preferably a thiophosphoric triamide; preferably N-(n-butyl)thiophosphoric triamide (NBPT) and / or N-(n-propyl)thiophosphoric triamide (NPPT). [4] The particulate composition according to any of the preceding claims, wherein the one polyhydric alcohol or the several polyhydric alcohols is / are selected independently of one another from monosaccharides, disaccharides and oligosaccharides; preferably monosaccharides; particularly preferably glucose and / or fructose. [5] The particulate composition according to any of the preceding claims, wherein component (i) comprises two or more polyhydric alcohols; preferably glucose and fructose; more preferably isoglucose or invert sugar; more preferably corn syrup or invert sugar syrup. [6] The particulate composition according to any of the preceding claims, wherein the total content of the one polyhydric alcohol or the several polyhydric alcohols is in the range of 0.001 to 1.5 wt.%, preferably 0.002 to 1.0 wt.%; preferably 0.004 to 0.8 wt.%, more preferably 0.006 to 0.6 wt.%, more preferably 0.008 to 0.4 wt.%, and most preferably 0.01 to 0.2 wt.%; in each case relative to the total weight of the particulate composition. [7] The particulate composition according to any of the preceding claims, wherein the first polymer, preferably the amine-containing polymer, is selected from polyamines, polyalkylenemines, preferably polyethyleneimines and polypropyleneimines, polyvinylamines, polyalkoxylated polyamines, ethoxylated polyamines, propoxylated polyamines, and alkylated and / or benzylated polyamines; preferably polyamines, polyalkylenemines, preferably polyethyleneimines and polypropyleneimines, and polyvinylamines; more preferably wherein the first polymer is a polyethyleneimine and / or a polyvinylamine. [8] The particulate composition according to any of the preceding claims, wherein the total content of first polymer is in the range of 0.002 to 2.0 wt.%; preferably 0.004 to 1.5 wt.%, more preferably 0.006 to 1.0 wt.%, more preferably 0.008 to 0.75 wt.%, and most preferably 0.01 to 0.5 wt.%; in each case relative to the total weight of the particulate composition. [9] The particulate composition according to any one of the preceding claims, wherein the second polymer, preferably the polar polymer, is a vinyl polymer, a polyester, a polyether, or a polyacrylate; preferably a vinyl polymer, a polyester, or a polyether; more preferably the second polymer is selected from the group consisting of polyvinyl alcohol (PVOH), polyethylene glycol (PEG), polylactic acid (PLA), polyethylene glycol esters, butenediol-vinyl alcohol copolymer (BVOH), polyvinylpyrrolidone (PVP), and polyacrylamide (PAM); more preferably polyvinyl alcohol (PVOH), polyethylene glycol (PEG), polylactic acid (PLA), and polyethylene glycol esters; even more preferably polyvinyl alcohol (PVOH). [10] The particulate composition according to any of the preceding claims, wherein the second polymer is water-soluble and / or biodegradable. [11] The particulate composition according to any of the preceding claims, wherein the total polymer content is in the range of 0.002 to 1.0 wt.%; preferably 0.004 to 0.8 wt.%, more preferably 0.006 to 0.6 wt.%, more preferably 0.008 to 0.4 wt.%, and most preferably 0.01 to 0.2 wt.%; in each case relative to the total weight of the particulate composition. [12] The particulate composition according to any of the preceding claims, comprising one or more additives; preferably the additives comprise one or more of the following components: - Sulfur; - Ammonium sulfate; - at least one trace element. [13] An additive as defined in any of the preceding claims comprising the components (i), (ii) and optionally (iii) for producing a particulate composition as described above. [14] Use of an additive according to claim 13 for the production of a particulate composition according to any one of claims 1 to 12. [15] A method for producing a particulate composition according to any one of claims 1 to 12, wherein the method comprises the steps: (a) Providing an inhibitor composition which contains an inhibitor; (b) Providing a urea-containing solution and / or melt; (c) Granulating or pricking the urea-containing solution and / or melt to obtain a particulate composition; (d) optional cooling of the particulate composition; (e) optionally classifying the particulate composition to obtain particle fractions; (f) optionally separating a particle fraction obtained in step (e); and returning this separated particle fraction to the granulation or pricking device used in step (c); and (g) optional cooling of the particulate composition; wherein component (i), component (ii), and optionally component (iii) of an additive according to claim 13 are added independently of one another; preferably to the provided inhibitor composition or to the urea-containing solution and / or melt; wherein the inhibitor composition is added to the urea-containing solution or brought into contact with the particulate composition. [16] The method according to claim 15, wherein the temperature of the urea-containing solution is at least 120°C; preferably at least 125°C, and more preferably at least 130°C. [17] The method according to claim 15 or 16, wherein the addition of the additive to the urea-containing solution and / or melt takes place before or during step (c); preferably in step (c); more preferably before the solidification of the urea-containing solution and / or melt. [18] The method according to any one of claims 15 to 17, wherein - the additive is added, preferably before or during step (c), as a solid, liquid or suspension; preferably as a solution; more preferably as an aqueous solution; even more preferably as a urea-containing aqueous solution; and / or - the inhibitor composition is added, preferably before or during step (c), as a liquid or suspension to the urea-containing solution and / or melt, preferably as a solution. [19] The method according to any one of claims 15 to 18, wherein the addition of component (i), component (ii) and / or optional component (iii) to the urea-containing solution and / or melt is carried out together in one step or successively. [20] Use of a particulate composition according to any one of claims 1 to 12 as a fertilizer.

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