Emulsion for treating urea-containing fertilizers

Abstract

The invention relates to an emulsion for treating urea-containing fertilizers, containing an aqueous phase B and a non-aqueous phase A, which is emulsified with phase B, wherein phase A contains at least one (thio)phosphoric acid triamide of the general formula (I) and / or (thio)phosphoric acid diamide of the general formula (II), R1R2N-P(X)(NH2)2, R1O-P(X)(NH2)2where X means oxygen or sulfur, R1and R2mean, independently of each other, hydrogen, respectively substituted or unsubstituted 2-nitrophenyl, C1alkyl, C-10cycloaIkyl, C3-10heterocycloalkyl, C3-10aryl, C6-10heteroaryl or diaminocarbonyl, wherein R6-10and R1, together with the nitrogen atom connecting them, can also form a 5 or 6-membered saturated or unsaturated heterocyclic group, which can optionally also contain one or two additional heteroatoms, selected from the group consisting of nitrogen, oxygen and sulfur, as component A1, dissolved in an organic solvent, which is not miscible with water, as component A2, and wherein phase B 2-(N-3,4-dimethylpyrazole)succinic acid, which is present as dialkali salt, earth alkali salt, diammonium salt or a mixture thereof, as component B1, dissolved in water.

Description

[0001] Emulsion for the treatment of urea-containing fertilizers Description

[0002] The invention relates to an emulsion for the treatment of urea-containing fertilizers, containing at least one (thio)phosphoric triamide and 2-(N-3,4-dimethylpyrazole)succinic acid, as well as its use and a process for the production of treated urea-containing fertilizers and urea-containing fertilizers thus obtainable.

[0003] Worldwide, the vast majority and ever-increasing amount of nitrogen used for fertilization is applied in the form of urea or urea-containing fertilizers. However, urea itself is a form of nitrogen that is not, or only minimally, absorbed, as it is relatively quickly hydrolyzed to ammonia and carbon dioxide by the ubiquitous soil enzyme urease. In some cases, gaseous ammonia is released into the atmosphere, which is then no longer available to plants in the soil, thus reducing the efficiency of fertilization.

[0004] It is known that nitrogen utilization when using urea-containing fertilizers can be improved by applying these fertilizers together with substances that can reduce or inhibit enzymatic urea hydrolysis. Among the most potent known urease inhibitors are N-alkylthiophosphoric triamides and N-alkylphosphoric triamides, which are described, for example, in EP 0 119 487.

[0005] Mixtures of N-alkylthiophosphoric triamides such as N-(n-butyl)thiophosphoric triamide (NBPT) and N-(n-propyl)thiophosphoric triamide (NPPT) can also be used, for example in a weight ratio of NBPT to NPPT of about 3 : 1.

[0006] These urease inhibitors are described, for example, in WO 2009 / 079994. For this class of compounds to act as urease inhibitors, they must first be converted into the corresponding oxo form. This then reacts with the urease and inhibits it.

[0007] It is recommended to apply urease inhibitors to the soil along with the urea, as this ensures that the inhibitor comes into contact with the soil along with the fertilizer. The active ingredient can be incorporated into the urea, for example, by being dissolved into the melt before urea granulation or pricking. Another option is to apply the active ingredient directly to the urea granules or prills, for example, in the form of a solution.

[0008] Suitable application methods and solvents are described, for example, in EP-A-1 820 788. Water, alcohols, glycols, or amines, as well as mixtures thereof, are mentioned as solvents. Reference is also made to WO 97 / 22568. WO 97 / 22568 concerns improved formulations of N-alkylthiophosphoric triamides applied as urease inhibitors to fertilizers. These are dissolved in a glycol or glycol derivative. Propylene glycol or dipropylene glycol, which are water-miscible glycols, are used in particular.

[0009] WO 2009 / 079994 concerns mixtures for the treatment of urea-containing fertilizers, which also contain (thio)phosphoric triamides. These mixtures also contain at least one compound with an amino group or a substituted amino group and a boiling point above 100 °C. Solvents for the (thio)phosphoric triamides are also described, including water, alcohols, glycols, N-methyl-2-pyrrolidone (NMP), and dimethyl phthalate (DMP). Most of the proposed solvents, such as glycols and NMP, are readily miscible with water. Dimethyl phthalate, which is used according to the examples, is sparingly soluble in water.

[0010] EP-A-3 109 223 concerns mixtures for the treatment of urea-containing fertilizers. The synergistic mixture of urease inhibitor and nitrification inhibitor contains (thio)phosphoric triamides and 2-(N-3,4-dimethylpyrazole)succinic acid. These synergistic mixtures are applied to urea-containing fertilizers, and a mixture of both components may also contain a solvent for the (thio)phosphoric triamides. The mixtures themselves are used as additives or coating agents for urea-containing nitrogen fertilizers. Water, alcohols, glycols, as well as NMP or dimethyl phthalate are mentioned as solvents. The method and sequence of application to the urea-containing fertilizer are not specified.

[0011] WO 2013 / 121384 concerns mixtures for reducing ammonia or nitrogen oxide emissions from soils. These mixtures contain alkylthiophosphoric triamides and at least one strobilurin. They may also contain nitrification inhibitors such as 2-(N-3,4-dimethylpyrazole)succinic acid or 3,4-dimethylpyrazole phosphate. The use of solvents is also mentioned. Ingredients dissolved in an organic solvent can be emulsified in water.

[0012] DE 103 17 895 A1 relates to 1,3,4-oxa- and 1,3,4-thiadiazol-2-yl(thio)phosphoric triamides, processes for their production, and their use as agents for regulating or inhibiting enzymatic urea hydrolysis. The description states that the urease inhibitor is water-soluble. It also indicates that it can be easily combined with nitrification inhibitors. Furthermore, it states that the urease inhibitors can be used in liquid form, for example, as a solution, emulsion, or suspension, or in solid form.

[0013] WO 2015 / 104699 A2 concerns combinations of new nitrification inhibitors with fungicides or with (thio)phosphoric triamides and fungicides. The nitrification inhibitors of formula (I) contain an alkyne group. In addition to those of formula (I), DMPP or DMPSA may also be used as nitrification inhibitors. Both compounds are listed in a longer document. It is stated that NBPT or nitrification inhibitors may be in the form of solutions, emulsions, suspensions, dusts, powders, pastes, or granules.

[0014] Typically, (thio)phosphoric triamides, such as NBPT and NPPT, and nitrification inhibitors, such as 2-(N-3,4-dimethylpyrazole)succinic acid (DMPSA) or 3,4-dimethylpyrazole phosphate (DMPP), are applied separately to fertilizers. This means that the active substances are applied sequentially in their respective formulations to urea granules. There are several reasons for this approach: formulations containing both active ingredients in a single solution have significant disadvantages.

[0015] Firstly, both substances cannot be dissolved together in aqueous media at the desired concentration. While this is possible with some organic solvents and mixtures, both active ingredients decompose very rapidly in such solutions. Coating urea-containing fertilizers with NBPT and DMPSA or DMPP has therefore only been possible so far by sequentially applying individual formulations. The disadvantage of this approach lies in the considerable technical effort required, as two coating steps and additional process steps are necessary. This leads to a significantly longer process time. Furthermore, storage capacity must be provided for the intermediate storage of the semi-finished fertilizer. Moreover, storage stability tests showed that the NBPT concentrations in the finished fertilizer decrease unexpectedly rapidly during storage.

[0016] The object of the present invention is to provide a mixture of urease inhibitors and nitrification inhibitors suitable for application to urea-containing fertilizers, which avoids the disadvantages mentioned above. Furthermore, an improved process for producing fertilizers treated with urease inhibitor and nitrification inhibitor is to be provided, which is technically simple and leads to treated fertilizers with increased storage stability.

[0017] A further object of the present invention is to provide a mixture for treating urea-containing fertilizers, in particular for urease inhibition, which, after application to urea-containing fertilizers, is stable for extended periods of time, better withstands passage through various distribution stages, and protects the active ingredient applied to the urea from decomposition or loss. The mixture should not negatively affect the activity of the active ingredient.

[0018] The problems are solved according to the invention by an emulsion for the treatment of urea-containing fertilizers, comprising an aqueous phase B and a non-aqueous phase A emulsified with phase B, wherein phase A comprises at least one (thio)phosphoric triamide of general formula (I) and / or (thio)phosphoric diamide of general formula (II).

[0019] R 1 R 2 NP(X)(NH2)2(I)

[0020] R 10-P(X)(NH2)2(N) with the meaning

[0021] X Oxygen or sulfur,

[0022] R1 and R2 independently of each other hydrogen, each substituted or unsubstituted 2-nitrophenyl, Ci-10-alkyl, C3-10-cycloalkyl, C3-10-heterocycloalkyl, C 6-i o-Aryl, C 6-i o-Heteroaryl or diaminocarbonyl, wherein R 1 and R 2 together with the nitrogen atom connecting them, they can also form a 5- or 6-membered saturated or unsaturated heterocyclic residue, which may optionally also contain one or two further heteroatoms selected from the group consisting of nitrogen, oxygen and sulfur,

[0023] as component A1, dissolved in an immiscible organic solvent as component A2, contains,

[0024] and

[0025] wherein Phase B contains 2-(N-3,4-Dimethylpyrazole)succinic acid, preferably in the form of a dialkali salt, alkaline earth salt, diammonium salt or a mixture thereof, as component B1, dissolved in water.

[0026] The problems are also solved by using such an emulsion as an additive or coating agent for urea-containing nitrogen fertilizers.

[0027] The tasks are also solved by a process for the production of treated urea-containing fertilizers, comprising the steps

[0028] a) separate production of phases A and B as defined above,

[0029] b) Mixing phases A and B from step a) to produce an emulsion of phases A and B,

[0030] c) Applying the emulsion from step b) to a particulate urea-containing fertilizer or incorporating the emulsion from step b) into a particulate urea-containing fertilizer.

[0031] According to one embodiment of the invention, the emulsion and the treated urea-containing fertilizer do not contain strobilurin or are free of strobilurin as defined, for example, in WO 2013 / 121384.

[0032] The problems are also solved according to the invention by a urea-containing fertilizer obtainable by the method described above.

[0033] It has been found according to the invention that the coating of urea-containing fertilizers with special urease inhibitors and DMPSA as a nitrification inhibitor is easily possible if the two active ingredients are first dissolved separately in immiscible solvents, then an emulsion is produced from both solutions, and the urea-containing fertilizer is treated with the emulsion thus obtained.

[0034] It was found according to the invention that the urea-containing fertilizers produced in this way have a significantly improved storage stability with regard to the volatility of the active ingredients.

[0035] In particular, the NBPT concentration remains constant over a significantly longer storage period than is the case after sequential application of the active ingredients. This indicates that the active ingredients are deposited on the surface of the urea-containing fertilizer in a different form than after the known process, resulting in a differently treated urea-containing fertilizer.

[0036] The use of the emulsion according to the invention for coating the urea-containing fertilizer leads to altered physical properties of the fertilizer.

[0037] Thus, the emulsion according to the invention not only allows for a simple and efficient simultaneous application of both active ingredients to urea-containing fertilizers, but also results in a significantly higher shelf life of the product compared to treated fertilizers produced according to previously known methods.

[0038] In contrast to DMPSA, particularly the neutralized or salt form, the use of DMPP instead of DMPSA in the emulsion and process according to the invention does not lead to products with significantly longer shelf life with respect to the urease inhibitor and nitrification inhibitor. In particular, rapid degradation of both substances was observed for the combination of DMPP and NBPT when used in an emulsion corresponding to the emulsion according to the invention.

[0039] The two active substances, (thio)phosphoric triamide and / or (thio)phosphoric diamide as a urease inhibitor and DMPSA as a nitrification inhibitor, are used in their respective individual formulations. DMPSA is used in an aqueous solution, preferably with a pH in the range of 6 to 9, particularly preferably 7 to 8. Therefore, DMPSA is preferably used in neutralized form as a dialkali salt, alkaline earth salt, diammonium salt, or a mixture thereof. The urease inhibitor is dissolved in an immiscible organic solvent and preferably combined with a compound containing an amino group or a substituted amino group, in particular an amine, with a boiling point above 100 °C. The term "amine" preferably excludes heterocycles such as pyrazoles or dicyandiamide (DCD).

[0040] The two formulations, which are immiscible, are combined in a specific ratio and homogenized to form an emulsion by brief mixing. This emulsion is usually not stable over time, but rather separates again after only a few minutes of standing, especially if no dispersing agent is used.

[0041] This emulsion mixture is applied evenly to the urea-containing fertilizer as soon as possible after production, preferably in a mixer while the urea-containing fertilizer is agitated. The mixing process is preferably continued for a few minutes after application is complete. The finished, treated urea-containing fertilizer can then be dried, for example, by leaving it to stand in the open bag for several days. If necessary, a separate drying step can be carried out.

[0042] DMPSA (especially in neutralized form) is highly water-soluble and does not decompose in water. When treating solid, particulate urea-containing fertilizer, the water is quickly absorbed into the fertilizer.

[0043] The emulsion for treating urea-containing fertilizers allows a synergistic combination of urease inhibition and nitrification inhibition.

[0044] The additional ammonia emissions that usually occur can be prevented by the nitrification inhibitor DMPSA contained within.

[0045] Compared to separately used urease inhibitors and nitrification inhibitors, a comparable effect can be achieved with lower application rates.

[0046] Nitrogen losses from the urea-containing fertilizer during application are avoided by the inventive mixture.

[0047] The urea-containing fertilizer contains the emulsion according to the invention in such a quantity that the total content of components A and B, based on the urea contained, is preferably 0.001 to 0.5 wt.%, preferably 0.02 to 0.4 wt.%, in particular 0.08 to 0.25 wt.%.

[0048] It was found according to the invention that in particular 2-(N-3,4-dimethylpyrazole)succinic acid (also known as DMPSA or DMPBS) in mixture with (thio)phosphoric triamides of general formula (I) and / or (thio)phosphoric diamides of general formula (II) yields synergistically effective mixtures for the treatment of urea-containing fertilizers.

[0049] According to the invention, the usual amounts of urease inhibitor (component A) and nitrification inhibitor (component B) used could be significantly reduced without any appreciable loss of efficacy, so that the total amount of active ingredient in the mixture is only about half that of when using the individual substances. As stated above, the enzyme urease hydrolyzes urea relatively rapidly to ammonia and carbon dioxide. This process can be delayed or slowed down by using urease inhibitors.

[0050] Nitrification inhibitors prevent the premature conversion of nitrogen in fertilizers into nitrate, which can easily be washed away by rainwater, for example, and thus lost to the plants.

[0051] Typical nitrification inhibitors such as 3,4-dimethylpyrazole typically increase ammonia emissions from urea-containing fertilizers significantly, partly because the pH remains in the alkaline range for a longer period after hydrolysis. At these elevated pH values, the ammonia emission potential is considerably higher than at lower pH values. While the formation of N₂O and nitrate leaching decrease with the use of a nitrification inhibitor, this desired effect comes at the cost of increased ammonia emissions and thus nitrogen loss via ammonia.

[0052] Therefore, although a urease inhibitor is frequently used on urea-containing fertilizers, a nitrification inhibitor is not.

[0053] The (thio)phosphoric triamides of general formula (I) or (thio)phosphoric diamides of general formula (II), in particular N-(n-butyl)thiophosphoric triamide (NBPT) or N-(n-propyl)thiophosphoric triamide (NPPT), inhibit or limit ammonia emissions from urea and the additional ammonia emissions when 2-(N-3,4-dimethylpyrazole)succinic acid is used as a nitrification inhibitor. This not only sufficiently inhibits nitrification by the nitrification inhibitor and significantly reduces nitrous oxide losses, but also greatly reduces ammonia losses, thus stabilizing the urea for a longer period.

[0054] This effect occurs specifically when the nitrification inhibitor DMPSA according to the invention is used in combination with the urease inhibitors according to the invention. Nitrification inhibition and urease inhibition continue to occur simultaneously with reduced dosages of both active substances, as described in EP-A-3 109 23.

[0055] As a result, when the nitrification inhibitor DMPSA and the urease inhibitor NBPT are used together, the effects of both inhibitors are maintained and mutually enhance each other, so that the total amount of both active ingredients can be more than halved.

[0056] Compared to the usual dosage of the individual substances when used alone, the amount of DMPSA can be reduced by up to 2 / 3 (e.g., from 0.36 wt% to 0.12 wt%), and the amount of NBPT by up to 1 / 3 (e.g., from 0.06 wt% to 0.04 wt%), in each case based on urea. Since DMPSA is typically used in significantly larger quantities than NBPT, this substantial reduction in dosage has a greater impact.

[0057] Component A1 consists of at least one (thio)phosphoric triamide of general formula (I) and / or one (thio)phosphoric diamide of general formula (II). These can be single compounds or mixtures of two or more such compounds. For example, they can be mixtures such as those described in EP-A-

[0058] 1,820,788 are described.

[0059] The remains R 1 and R 2They can be unsubstituted or substituted, e.g. by halogen and / or nitro.

[0060] Examples of alkyl groups are methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, pentyl, isopentyl, neopentyl, tert-pentyl, hexyl, 2-methylpentyl, heptyl, octyl, 2-ethylhexyl, isooctyl, nonyl, isononyl, decyl, and isodecyl. Cycloalkyl groups include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and cyclooctyl. Aryl groups include phenyl and naphthyl, or substituted 2-nitrophenyl. Examples of heterocyclic R1R2N- groups are piperazinyl, morpholinyl, pyrrolyl, pyrazolyl, triazolyl, oxazolyl, thiazolyl, and imidazolyl groups.

[0061] Such compounds are known, for example, from EP 0 119 487, WO 00 / 58317 and EP 1 183 220 as urease inhibitors.

[0062] An example of compounds of formula (II) is phenylphosphordiamidate.

[0063] Preferred are preparations containing N-(n-butyl)thiophosphoric triamide (NBPT) as one or the sole active ingredient (component A1). If another active ingredient is also used, it is preferably a derivative selected from the group consisting of N-cyclohexyl-, N-pentyl-, N-isobutyl-, and N-propylphosphoric triamides and corresponding thiophosphoric triamides. NPPT is preferably also used. Particularly preferred are preparations containing NBPT or a mixture of NBPT and NPPT in amounts of 40 to 100 wt.%, and most preferably in amounts of 60 to

[0064] 100 wt%, each based on the total amount of active ingredient of component A1. In a mixture of NBPT and NPPT, the compounds are preferably present in a weight ratio of 19 : 1 to 1 : 19, more preferably of 9 : 1 to 1 : 9, and particularly preferably of 8 : 2 to

[0065] 2 : 8, especially preferably from 1 : 1 to 5 : 1, in particular from 2 : 1 to 4 : 1, for example from about 3 : 1 (75% : 25%).

[0066] Particularly preferably, only NBPT or a mixture of NBPT and NPPT, preferably in a weight ratio of 2:1 to 4:1, is used as component A1. Thiophosphoric triamides are known to react relatively readily with the corresponding phosphoric triamides. Since moisture cannot usually be completely excluded, thiophosphoric triamide and the corresponding phosphoric triamide are frequently present in a mixture. Therefore, in this document, the term "(thio)phosphoric triamide" refers to both the pure thiophosphoric triamides and phosphoric triamides, as well as their mixtures.

[0067] N-alkylthiophosphoric triamides (with X = S and R) are particularly preferred. 2 = H) and N-alkylphosphoric triamides (with X = O and R 2 = H).

[0068] The preparation of such urease inhibitors can be carried out, for example, using known methods from thiophosphoryl chloride, primary or secondary amines, and ammonia, as described, for instance, in US 5,770,771. In this process, thiophosphoryl chloride is first reacted with an equivalent of a primary or secondary amine in the presence of a base, and the product is then reacted with an excess of ammonia to give the final product.

[0069] Other suitable urease inhibitors that may be used additionally are described, for example, in WO 00 / 61522, WO 00 / 58317, WO 02 / 083697, WO 01 / 87898, and WO 2006 / 010389. The compounds described therein include, for example, thiophosphoric triamides, heterocyclically substituted (thio)phosphoric triamides, N-(2-pyrimidinyl)(thio)phosphoric triamides, and N-phenylphosphoric triamides.

[0070] EP-A-1 820 788 describes in particular mixtures of N-(n-butyl)thiophosphoric triamide and N-(n-propyl)thiophosphoric triamide.

[0071] According to the invention, these mixtures can be used particularly preferably alongside the individual substances.

[0072] The (thio)phosphoric triamides of general formula (I) or (thio)phosphoric diamides of general formula (II), used as component A1, can be pure substances or mixtures of two or more pure substances. They may also contain byproducts from the active pharmaceutical ingredient synthesis. Component A1 is generally present in a purity of at least 70%.

[0073] Component A1 is dissolved in an organic solvent that is immiscible with water (component A2). The term "immiscible with water" describes organic solvents whose solubility in water is a maximum of 1 g / l at 20 °C. Preferably, the solubility in water is a maximum of 100 mg / l at 20 °C. Suitable solvents are selected from immiscible alcohols, ethers, esters, hydrocarbons, polyalkylene polyols, such as immiscible polyalkylene glycols or glycol derivatives, and their ethers, liquid amides, or mixtures thereof, preferably from immiscible alcohols, ethers, esters, or mixtures thereof.

[0074] Preferably, component A2 is selected from 2-propyl-1-heptanol, benzyl alcohol, dimethyl phthalate, or mixtures thereof. For example, 2-propyl-1-heptanol has a water solubility of only 58 mg / l at 20 °C and is therefore considered water-insoluble.

[0075] Phase A preferably contains 15 to 35 wt.%, particularly preferably 20 to 30 wt.%, in particular 22 to 26.5 wt.% of component A1, based on the total weight of phase A.

[0076] Additionally, at least one compound containing an amino group or a substituted amino group, or an amine with a boiling point of more than 100 °C, can be used as component A3 in phase A.

[0077] Preferably, component A3 is not miscible with water, see the definition above.

[0078] Preferably, this compound is selected from methyldiethanolamine, tetrahydroxypropylethylenediamine, trimethylaminoethylethanolamine, N,N,N',N'-tetramethyl-1,6-hexanediamine, N,N',N'-tris(dimethylaminopropyl)hexahydrotriazine, 2,2'-dimorpholinyldiethyl ether,

[0079] N,N,N',N',N",N"-Hexa-methyl-1,3,5-triazine-1,3,5(2H,4H,6H)-tripropanamin, N,N,N',N'-

[0080] Tetrakis(2-hydroxypropyl)ethylenediamine or mixtures thereof, wherein component A3 is preferably used in at least 0.2 times the molar amount of component A1. The amine serves, among other things, to stabilize the urease inhibitor in the organic solution.

[0081] The active ingredient of component A1, when applied to urea, often exhibits significantly higher storage stability (at least two to three months) when used in combination with at least one amine with a boiling point above 100°C as component A3. Component A3 contains at least one amino group, e.g., a primary, secondary, or tertiary amino group, and may also contain any other functional groups and residues, such as hydroxy, halogen, carboxy, carbamoyl, carbonyl, oxyalkyl, mercapto, M-sulfido, sulfoxy, sulfo, phospho, siloxy, amino, amido, imino, imido, oxyamido groups, etc. Component A3 is described in more detail below as an example of an amine.

[0082] The amine of component A3 preferably has a boiling point of more than 150 °C, and particularly preferably more than 200 °C, at ambient pressure (1 bar). It can be a primary, secondary, or tertiary amine or a polyamine containing several of these amine groups. Secondary and / or tertiary amines are preferred. Tertiary amines, which may also be in polymeric form, are particularly preferred. Amines that do not undergo a chemical reaction with the active ingredient of component A1 or the co-used solvent of component A2 are preferred. For example, the amines of component A3 are selected from methyldiethanolamine, tetrahydroxypropylethylenediamine, trimethylaminoethylethanolamine, N,N,N',N'-tetramethyl-1,6-hexanediamine, N,N',N'-tris(dimethylaminopropyl)hexahydrotriazine, 2,2'-dimorpholinyldiethyl ether, or mixtures thereof.

[0083] For further suitable amines, reference can be made to WO 2016 / 103168, in particular the amines of groups L10 to L24 and L29 disclosed therein. Further suitable amines are described in WO 2015 / 001457, see in particular component (C) and specifically the amines described as components (C1) to (C5). Further suitable amines are described in WO 2018 / 007426, in particular as component B, selected from B1 to B4 under the general formulas (III) to (X). Reference can also be made to amino alcohols, such as those described in WO 2013 / 090324.

[0084] Amines are derivatives of ammonia in which the hydrogen atoms are replaced by organic molecular groups. If all three hydrogen atoms are replaced, they are called tertiary amines; if two hydrogen atoms are replaced, they are called secondary amines; and if one hydrogen atom is replaced, they are called primary amines.

[0085] Compounds that have a C=N bond, as in pyridine, do not belong to the amine classification according to the invention.

[0086] Saturated cyclic amines such as piperidine and pyrrolidine, as well as their (unsaturated) aromatic representatives pyridine and pyrrole, are treated as heterocyclic compounds and therefore not as amines.

[0087] Similarly, the cyano group -CN is not a tertiary amino group and hydrogen cyanide (H-CN) is not a tertiary amine.

[0088] The generic term "amine" is thus used for compounds NH2R, NHR 1 R 2 and NHR 1 R 2 R 3These are called primary, secondary, and tertiary amines. In a broader sense, compounds containing nitrogen as part of a ring, whose basicity can be attributed to this atom, can also be called "amines." For example, piperidine is a ring-shaped secondary amine based on its chemical structure.

[0089] Amides such as N-methylpyrrolidone (NMP) do not exhibit any stabilizing effect and are therefore not suitable as amines for use according to the invention. Dicyandiamide (DCD) is also not an amine, but rather an amide according to its chemical name. It is a cyanamide and guanidine derivative with negligible basicity.

[0090] According to the invention, the term "amines" does not include pyridines, guanidines, urea, thiourea, or dicyandiamide. (Thio)phosphoric triamides are also not considered amines according to the invention.

[0091] Component A3 is used in a quantity sufficient to increase the storage stability of the active ingredient of component A1 on urea-containing fertilizers. Preferably, component A3 should be used in at least 0.2 times the molar quantity of component A1, particularly preferably in 0.5 to 3 times the molar quantity, and especially in 1 to 2 times the molar quantity.

[0092] Furthermore, the stabilizing effect can be enhanced even further by adding polymeric additives.

[0093] According to the invention, polymers in dissolved or dispersed form can be included as a further component C in phase A. Polymers that do not undergo chemical reactions with components A1 and B1 are preferred. The polymers can be in solution, emulsion, or dispersed form. Soluble polymers are preferred, preferably those with a number-average molecular weight of at least 5000. Suitable polymers can be derived from vinylic monomers, for example, styrenes or (meth)acrylates or acrylonitrile. For example, soluble polystyrenes, soluble polystyrene-acrylonitrile polymers, or polymers containing graft rubbers can be used. Furthermore, polyesters or polyalkylene glycols can be used, for example. The stabilization of the urease inhibitors of component A1 is further improved by the addition of the polymers.They can also be used for delayed release of the mixture in a "controlled release" manner. The components are preferably present in the mixture in the following quantities.

[0094] The proportion of the amine of component A3 in phase A according to the invention, if present, is preferably 1 to 50 wt.%, particularly preferably 2 to 40 wt.%, and more preferably 3 to 35 wt.%. The amount of the optional polymer component C is preferably 0 to 50 wt.%, and more preferably 0 to 25 wt.%. If component C is present, the amount is preferably 1 to 50 wt.%, and more preferably 2 to 25 wt.%. The total amount of the components of phase A is 100 wt.%.

[0095] Component B1 of the emulsion according to the invention contains 2-(N-3,4-dimethylpyrazole)succinic acid (DMPBS or DMPSA) as a pyrazole compound with nitrification-inhibiting properties. This compound is known from the prior art and is described, for example, in WO 96 / 24566, WO 2011 / 032904, and WO 2013 / 121384. 2-(N-3,4-dimethylpyrazole)succinic acid is frequently an isomeric mixture of 2-(3,4-dimethyl-1H-pyrazole-1-yl)succinic acid and 2-(2,3-dimethyl-1H-pyrazole-1-yl)succinic acid, preferably in a ratio of about 80:20. Either of the individual compounds can also be used. According to the invention, salts of this compound(s) are preferably used, for example (di-)alkali salts, alkaline earth salts or (di-)ammonium salts, preferably alkali salts, especially potassium salts.

[0096] According to the invention, the aforementioned salts are also referred to as "DMPSA" or "DMPBS". Preferably, phase B has a pH value in the range of 6 to 9, particularly preferably from 7 to 8. This pH value can be adjusted by varying the amount of alkali hydroxide, alkaline earth hydroxide, or ammonia used to neutralize DMPSA.

[0097] Phase B should preferably have a pH as neutral as possible to prevent rapid hydrolysis of component A1 upon contact of the two solutions. It is known that NBPT, in particular, decomposes rapidly in aqueous solutions and emulsions at lower pH values ​​and is also unstable at higher pH values.

[0098] Component B1 is dissolved in water. The water may also contain small amounts of water-soluble additional solvents, for example, lower alkanols, N-methylpyrrolidone (NMP), or optionally dimethyl sulfoxide (DMSO). The amount of these solvents can be, for example, up to 10 wt%, preferably up to 5 wt%, based on the water and additional solvent. Preferably, water is used as the sole solvent for phase B. The term "aqueous phase" describes a phase with a predominant water content as the solvent. It contains component B1 dissolved in water.

[0099] Preferably, phase B contains 20 to 60 wt.%, particularly preferably 25 to 50 wt.%, and especially 30 to 40 wt.% of component B1, based on the total weight of phase B. These values ​​refer to the free acid (DMPSA) or to its salt form, preferably the salt form. When using the free acid (DMPSA), the upper limit can be reduced to 45 wt.%, preferably 40 wt.%, and particularly 35 wt.%.

[0100] Phase B particularly preferably contains only DMPSA and KOH in a molar ratio of 2 : 1, dissolved in water.

[0101] The preparation of 2-(N-3,4-dimethylpyrazole)succinic acid can be carried out by any suitable process, which is described, for example, in general form in WO 96 / 24566. Preferably, the preparation is carried out by reacting 3,4-dimethylpyrazole with maleic acid or maleic anhydride. This reaction is typically carried out in an acidic environment. For the preparation of 3,4-dimethylpyrazole, reference can be made to Noyce et al., Journal of Org. Chem. 20, 1955, pages 1681 to 1682. Reference can also be made to EP-A-0 474 037, DE-A-3 840 342 and EP-A-0 467 707, as well as to EP-B-1 120 388 and EP-A-3 109 223.

[0102] For the purification of 3,4-dimethylpyrazole, reference can be made to DE-A-10 2009 060 150.

[0103] A preferred manufacturing method is described in EP-A-3 109 223.

[0104] The volatility of 3,4-dimethylpyrazole can be greatly reduced by using the reaction product of 3,4-dimethylpyrazole with maleic acid.

[0105] Preferably, the emulsion, and thus both phase A and phase B, is free of fungicides such as those described, for example, in WO 2015 / 104699A2. Preferably, component A1 is not 1,3,4-oxa and 1,3,4-thiadiazol-2-yl(thio)phosphoric triamide of general formula (I).

[0106] where in formula (I) mean:

[0107] X, Y = independently of each other oxygen or sulfur

[0108] R 1 , R 2= independently hydrogen, CrC8-alkyl / heteroalkyl, C2-C8-alkenyl / heteroalkenyl, C2-C8-alkynylheteroalkynyl, C3-C8-cycloalkyl / heterocycloalkyl, C3-C8-cycloalkenyl / heterocycloalkenyl, C6-Cio-aryl / heteroaryl, aralkyl, Heteroarylalkyl, Alkaryl, Alkheteroaryl, Alkoxy, Aryloxy, Hetaryloxy, Alkylthio, Arylthio, Hetarylthio, Acyl, Aroyl, Hetaroyl, Acyloxy, Aroyloxy, Hetaroyloxy, Alkoxycarbonyl, Aryloxycarbonyl, Hetaryloxycarbonyl, Amino, Alkylamino, Dialkylamino, Alkylsulfonyl, Arylsulfonyl, Fluorine, Chlorine, Bromine, iodine, Hydroxy, Cyano, Nitro, Sulfo, Carbonyl, Carboxy, Carbamoyl, sulfamoyl, wherein the R groups 1 and / or R 2 They may themselves be substituted independently with one or more of the above-mentioned groups.

[0109] Phases A and B are mixed together in such quantities to form an emulsion that components A1 and B1 are present in a weight ratio of 1 : 1 to 1 : 6, preferably 1 : 1.5 to 1 : 5, in particular 1 : 2 to 1 : 4.5, specifically 1 : 2.5 to 1 : 4.

[0110] According to one embodiment of the invention, the emulsions can be produced without emulsifying or dispersing agents, such as surfactants, which are commonly used to stabilize oil / water emulsions. If, preferably, the emulsion is produced by mixing phases A and B immediately before coating the solid, particulate, urea-containing fertilizer, and application to the fertilizer takes place immediately thereafter, the emulsions are sufficiently stable for this short period required, so that the use of an emulsifying or dispersing agent can be dispensed with. In this case, the emulsions are free of emulsifying or dispersing agents.

[0111] According to an alternative embodiment of the compound, the emulsions contain emulsifying agents or dispersing agents. Their quantity is typically 0.01 to 5 wt.% when used together, preferably 0.02 to

[0112] 2 wt.%, in particular 0.1 to 1 wt.%, based on the sum of phases A and B, which yields 100 wt.%. Suitable emulsifying and dispersing agents are known to those skilled in the art. These may be, in particular, anionic, cationic, non-ionic, or amphoteric surfactants. For example, non-ionic surfactants such as alkylaryl polyether alcohols, as described, for example, in WO 97 / 22568, may be used. According to the invention, it is particularly preferred to work without emulsifying and dispersing agents.

[0113] Preferably, highly concentrated solutions are used in phases A and B, thus reducing the solvent content. However, the total quantity of the emulsion should be such that a uniform coating of urea-containing fertilizers is achieved, applying the aforementioned preferred concentrations of components A1 and B1 to the fertilizer.

[0114] At a standard concentration of 35 wt% component B1 in phase B and 23 wt% component A1 in phase A, phases A and B are preferably used in a weight ratio of 1:2 to 1:2.5, specifically approximately 1:2.3. For other substance concentrations of phases A and B, the ratio must be adjusted accordingly.

[0115] The typical application rate of the emulsion to a urea-containing fertilizer depends on the amide-N content of the fertilizer and the amounts or concentrations of the active ingredients.

[0116] Fertilizer mixtures preferably contain 100 to 3000 ppm by weight, based on the urea content in the fertilizer, of nitrification inhibitor (0.01 to 0.3 wt%), particularly preferably 0.03 to 0.2 wt% DMPSA, and especially 0.04 to 0.18 wt% DMPSA. Preferably, these amounts refer to the free acid (DMPSA) and are to be increased accordingly when using its salts, e.g., by a factor of 1.4.

[0117] The urea-containing fertilizer mixtures preferably contain 100 to 800 wt.% ppm, based on the fertilizer, of component A1 (0.01 to 0.08 wt.%), particularly preferably 0.01 to 0.07 wt.%, and especially 0.018 to 0.06 wt.% of component A1, in particular NBPT. Components A1 and B1 are preferably present in the fertilizer in a weight ratio in the range of 1:1 to 1:6, particularly preferably 1:1.5 to 1:5, and especially 1:2 to 1:4.5, and specifically 1:2.5 to 1:4.

[0118] The invention also relates to a urea-containing fertilizer containing an emulsion as described above, in such a quantity that the total content of components A1 and B1, based on the urea content, is 0.02 to 0.38 wt.%. The content of components A1 and B1, based on the urea content, is particularly preferably 0.04 to 0.27 wt.%, and especially 0.058 to 0.24 wt.%. In the urea-containing fertilizer, the emulsion is preferably applied to the surface of the fertilizer.

[0119] The production of the urea-containing fertilizers according to the invention is carried out by a process comprising the following steps:

[0120] a) separate production of phases A and B as defined above,

[0121] b) Mixing phases A and B from step a) to produce an emulsion of phases A and B,

[0122] c) Applying the emulsion from step b) to a particulate urea-containing fertilizer or incorporating the emulsion from step b) into a particulate urea-containing fertilizer.

[0123] The mixing of phases A and B in step b) can be carried out at room temperature or at an elevated temperature of, for example, 30 to 60 °C. Mixing is particularly preferably carried out at a temperature in the range of 20 to 40 °C.

[0124] The mixing of phases A and B can be carried out by a static or moving mixer, for example, an agitator. Preferably, the mixing of phases A and B to produce an emulsion takes place immediately before the application of the emulsion to the particulate urea-containing fertilizer, as this effectively prevents decomposition of the ingredients. Preferably, there is a period of no more than 60 seconds, particularly preferably no more than 30 seconds, between steps c) and b), and in particular, the period should be kept as short as possible (less than 15 seconds).

[0125] Step c) preferably involves spraying and / or drumming the emulsion onto the urea-containing fertilizer. The urea-containing fertilizer is preferably agitated during this process.

[0126] This can also be achieved using additional additives, such as adhesion promoters or coating materials. Suitable equipment for this application includes, for example, discs, drums, mixers, or fluidized bed systems; however, application can also be carried out on conveyor belts or their discharge points, or by means of pneumatic solids conveyors. A final treatment with anti-caking agents and / or dust suppressants is also possible. The fertilizers or emulsions according to the invention are used in fertilization with urea-containing fertilizers. Application is preferably carried out on agriculturally or horticulturally used soil, such as arable land.

[0127] The urea-containing fertilizer is in particulate form. It can be powder, prill, compacts, or other regularly or irregularly shaped particles.

[0128] In urea-containing fertilizers, the urea content is preferably 20 to 100 wt.%, particularly preferably 50 to 100 wt.% or 100 wt.%. Other possible ingredients are the usual ingredients of NPK fertilizers.

[0129] The term "urea-containing fertilizer" refers first and foremost to urea itself. In commercially available fertilizer quality, this has a purity of at least 90% and can be in crystalline, granulated, compacted, prilled, or ground form, for example. It also includes mixtures of urea with one or more other nitrogen fertilizers, such as ammonium sulfate, ammonium nitrate, ammonium chloride, cyanamide, dicyandiamide (DCD), or calcium nitrate, as well as slow-release fertilizers, such as urea-formaldehyde, urea-acetaldehyde, or urea-glyoxal condensates. Furthermore, it also includes urea-containing multi-nutrient fertilizers, which, in addition to nitrogen, contain at least one other nutrient, such as phosphorus, potassium, magnesium, calcium, or sulfur. Trace elements such as boron, iron, copper, zinc, manganese, or molybdenum may also be present.Such urea-containing multi-nutrient fertilizers can also be granulated, compacted, prilled, ground, or in crystalline form. These fertilizers may also contain one or more additional active ingredients, such as nitrification inhibitors, herbicides, fungicides, insecticides, growth regulators, hormones, pheromones, or other plant protection products or soil amendments, in amounts ranging from 0.01% to 20% by weight.

[0130] The invention also relates to a urea-containing fertilizer obtainable according to the above method.

[0131] The emulsions according to the invention can be used as an additive or coating agent for urea-containing nitrogen fertilizers.

[0132] As an additive, they can be applied to soil or planting substrate before, after, or together with a urea-containing nitrogen fertilizer. The emulsion according to the invention can be dosed separately from the urea-containing nitrogen fertilizer. More frequently, the emulsion according to the invention is applied to the urea-containing nitrogen fertilizer as a coating agent. When used as an additive for urea-containing nitrogen fertilizers, the emulsions according to the invention are preferably used in the emulsions in an amount of 0.001 to 0.5 wt.%, based on the weight of the urea in the nitrogen fertilizer and on components A1 and B1. The invention is explained in more detail by the following examples.

[0133] Examples

[0134] In the following examples, the following means

[0135] NBPT: N-(n-butyl)-thiophosphoric triamide = urease inhibitor Ul

[0136] DMPSA or DMPBS: 2-(N-3,4-Dimethylpyrazole)succinic acid = nitrification inhibitor (NI)

[0137] A. Examples of preparations for 2-(N-3,4-Dimethylpyrazole)succinic acid (DMPSA)

[0138] The manufacturing process is carried out as described in EP-A-3 109 223 in Examples 1 or 2.

[0139] B. Production of phases A and B

[0140] 79 g of a DMPSA formulation were prepared as a 35 wt% aqueous, pH-neutral formulation of DMPSA as the dipotassium salt.

[0141] 35 g of an NBPT formulation were prepared as a 23 wt% anhydrous solution of NBPT in 2-propyl-1-heptanol, with the addition of 46 wt% of a mixture of N,N,N',N',N",N"-hexa-methyl-1 ,3,5-triazine-1 ,3,5(2H,4H,6H)-tripropanamine and N,N,N',N'-tetrakis(2-hydroxypropyl)ethylenediamine.

[0142] C. Applying phases A and B to the fertilizer

[0143] 20 kg of granulated urea were placed in a mixer. 35 g of the NBPT formulation and 79 g of the DMPSA formulation were added to a spray bottle and shaken until a uniform emulsion was formed. The formulation emulsion was immediately sprayed onto the urea, with the spray bottle being shaken intermittently to prevent settling. The mixer was operated for a further 10 minutes until a homogeneous product was obtained.

[0144] In a comparative experiment, identical amounts of DMPSA and NBPT were applied to urea. First, the DMPSA formulation was applied to the urea according to the above procedure, and after drying, the NBPT formulation was applied.

[0145] Storage stability tests were performed for both treated urea fertilizers. Storage took place over 90 days under standard conditions in a climate chamber. The NBPT and DMPSA content was determined at intervals. Figure 1 shows the decrease in NBPT and DMPSA content over time after the specified number of days for the reference formulation. Figure 2 shows the results of the stability test for the urea-containing fertilizers according to the invention, in which DMPSA and NBPT were applied as an emulsion mixture.

[0146] The figures clearly show that the decrease in both DMPSA and NBPT for the urea-containing fertilizers produced according to the invention was significantly lower than in the comparison experiment.

[0147] D. Attempts at a solution

[0148] Furthermore, attempts to solve DMPSA and NBPT were carried out:

[0149] In aqueous media, the solubility of NBPT was far too low to achieve a sufficiently high concentration. The application rate of the solution for use on fertilizers would be too high.

[0150] Although both active substances were soluble in sufficient quantities in common organic solvents, chemical reactions between NBPT and solvent components or between the two active substances occurred after a short time, resulting in decomposition.

[0151] This implies that there is no way to keep both active substances stable together in suitable concentrations in the same solvent system.

[0152] E. Comparative trials

[0153] In the comparative experiment, 79 g of a DMPP formulation (35 wt% aqueous, pH-neutral formulation) was used in phase B instead of a DMPBS formulation. Otherwise, the procedure was the same as described in examples B and C.

[0154] Rapid degradation was observed for both NBPT and DMPP in the treated urea fertilizers. After 7 days, approximately 50% of the DMPP and 100% of the NBPT had degraded. HPLC chromatograms for both treated urea fertilizers indicate chemical reactions between the two substances that lead to the degradation of DMPP and NBPT.

Claims

Patent claims 1 Emulsion for the treatment of urea-containing fertilizers, comprising an aqueous phase B and a non-aqueous phase A emulsified with phase B, wherein Phase A comprises at least one (thio)phosphoric triamide of general formula (I) and / or (thio)phosphoric diamide of general formula (II) R 1 R 2 NP(X)(NH2)2(I) R 1 0-P(X)(NH2)2(II) with the meaning X Oxygen or sulfur, R 1 and R 2 independently of each other hydrogen, each substituted or unsubstituted 2-nitrophenyl, Ci-10-alkyl, C3-10-cycloalkyl, C3-10-heterocycloalkyl, C 6- -io-aryl, C6-io-heteroaryl or diaminocarbonyl, where R 1 and R 2together with the nitrogen atom connecting them, they can also form a 5- or 6-membered saturated or unsaturated heterocyclic residue, which may optionally also contain one or two further heteroatoms selected from the group consisting of nitrogen, oxygen and sulfur, as component A1, dissolved in an immiscible organic solvent as component A2, and wherein Phase B contains 2-(N-3,4-Dimethylpyrazole)succinic acid, preferably in the form of a dialkali salt, alkaline earth salt, diammonium salt or a mixture thereof, as component B1, dissolved in water.

2. Emulsion according to claim 1, characterized in that the (thio)phosphoric acid triamides of the general formula (I) are N-alkylthiophosphoric acid triamides with the meanings X = S and R. 2 = H and / or N-alkylphosphoric triamides with the meanings X = O and R 2 = H can be used.

3. Emulsion according to claim 1 or 2, characterized in that phase A comprises at least one compound containing an amino group or a substituted amino group with a boiling point of more than 100 °C, preferably an amine, particularly preferably selected from methyldiethanolamine, tetrahydroxypropylethylenediamine, trimethylaminoethylethanolamine, N,N,N',N'-tetramethyl-1,6-hexanediamine, N,N',N"- Tris(dimethylaminopropyl)hexahydrotriazine, 2,2'-dimorpholinyldiethyl ether, N,N,N',N',N",N"-Hexa-methyl-1 ,3,5-triazine-1 ,3,5(2H,4H,6H)-tripropanamine, N,N,N',N'-Tetrakis(2-Hydro-xypropyl)ethylenediamine or mixtures thereof, as component A3 in preferably at least 0.2 times the molar amount of component A1.

4. Emulsion according to one of claims 1 to 3, characterized in that phase A further contains a polymer in dissolved or dispersed form as component C.

5. Emulsion according to any one of claims 1 to 4, characterized in that components A1 and B1 are present in a weight ratio in the range of 1 : 1 to 1 : 6, preferably 1 : 1.5 to 1:5, in particular 1:2 to 1:4.5, are present.

6. Emulsion according to one of claims 1 to 5, characterized in that component A1 is N-(n-butyl)-thiophosphoric triamide or a mixture of N-(n-butyl)-thiophosphoric triamide and N-(n-propyl)-thiophosphoric triamide.

7. Emulsion according to any one of claims 1 to 6, characterized in that component A2 is selected from water-immiscible alcohols, ethers, esters, hydrocarbons, polyalkylene polyols and their ethers, liquid amides or mixtures thereof, and preferably is selected from 2-propyl-1-heptanol, dimethyl phthalate, benzyl alcohol or mixtures thereof.

8. Emulsion according to any one of claims 1 to 7, characterized in that phase B has a pH value in the range of 6 to 9, preferably from 7 to 8.

9. Emulsion according to any one of claims 1 to 8, characterized in that phase A contains 15 to 35 wt.%, preferably 20 to 30 wt.%, in particular 22 to 26.5 wt.% of component A1, based on the total weight of phase A.

10. Emulsion according to any one of claims 1 to 9, characterized in that phase B contains 20 to 60 wt.%, preferably 25 to 50 wt.%, in particular 30 to 40 wt.% of component B1, based on the total weight of phase B.

1. Use of an emulsion according to any one of claims 1 to 10 as an additive or coating agent for urea-containing nitrogen fertilizers.

12. Use according to claim 1 1 , characterized in that the emulsion is applied separately or simultaneously with the fertilizer to soil or planting substrate or is introduced into the fertilizer or applied to the fertilizer.

13. Method for the production of treated urea-containing fertilizers, comprising the steps a) separate production of phases A and B as defined in any one of claims 1 to 10, b) Mixing phases A and B from step a) to produce an emulsion of phases A and B, c) Applying the emulsion from step b) to a particulate urea-containing fertilizer or incorporating the emulsion from step b) into a particulate urea-containing fertilizer.

14. Method according to claim 13, characterized in that there is a period of at most 60, preferably at most 30 seconds, between step c) and step b).

15. Method according to claim 13 or 14, characterized in that in step c) the emulsion is sprayed and / or drummed onto the urea-containing fertilizer.

16. Method according to one of claims 13 to 15, characterized in that in step c) an emulsion according to one of claims 1 to 10 is applied to or introduced into the urea-containing fertilizer in such an amount that the total content of components A and B, based on the urea contained in the fertilizer, is 0.02 to 0.38 wt.%, preferably 0.04 to 0.27 wt.%.

17. Method according to one of claims 13 to 16, characterized in that in step c) the emulsion is applied to the surface of the particulate urea-containing fertilizer.

18. Urea-containing fertilizer obtainable by the process according to one of claims 13 to 17.

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