Liquid preparation containing urease inhibitor and application thereof

Abstract

The present invention relates to a fertilizer additive, and in particular to a liquid preparation containing a urease inhibitor. The liquid preparation comprises the following components in parts by weight: 16-36 parts of a urease inhibitor, 41-150 parts of a solvent, 3-14 parts of a cosolvent, and 0.6-3 parts of a regulator; wherein the urease inhibitor is N-n-butylthiophosphoric triamide; the solvent is a mixture of one or more ketones having 3 to 7 carbon atoms; the cosolvent is a mixture of one or more diol or triol derivatives; and the regulator is a mixture of one or more triethanolamine, diethanolamine, or an alkyldiethanolamine having an alkyl group having 1 to 4 carbon atoms. The liquid preparation containing a urease inhibitor prepared using the liquid preparation has good solubility and anti-coagulation properties at room temperature and low temperature, and can be stably present at both room temperature and high temperature. When applied to fertilizer, the fertilizer does not dissolve and does not clump.

Description

Technical Field

[0001] The present invention relates to a fertilizer additive, in particular to a liquid preparation containing a urease inhibitor. Background Art

[0002] Urease in the soil catalyzes the hydrolysis of urea, releasing ammonia that is easily volatilized. This portion of urea can cause losses of over 60%, a major cause of urea nitrogen fertilizer losses. To slow this hydrolysis process, urease inhibitors have been widely used in urea-based nitrogen fertilizers. They have been shown to slow the rate of urea hydrolysis and effectively improve crop nitrogen absorption and utilization. n-Butylthiophosphoric triamide (NBPT) is the most typical and widely used compound of this type of inhibitor. It has been widely used in fertilizer applications internationally, achieving excellent results in reducing nitrogen consumption and emissions.

[0003] However, because NBPT is a white, fine powdery solid that is sensitive to heat and water, it cannot be used in its solid form. When used at low concentrations, it is difficult to evenly distribute on urea blocks (i.e., large granules) and in soil. To evenly distribute NBPT on urea, it should be dispersed in an ideal solvent system before spraying it on urea. This solvent system allows NBPT to evenly distribute on granular urea (e.g., urea blocks) and in liquid fertilizers containing urea.

[0004] Therefore, the type of solvent is particularly critical for the liquid preparation of NBPT. Generally, the solvent selection should meet the following properties and requirements: (1) good solubility for the active ingredient of the urease inhibitor; (2) stable chemical properties, no chemical reaction with the active ingredient of the inhibitor or other components; (3) safety, non-toxic or low toxicity, good environmental compatibility, safe storage, use, and transportation, etc.; (4) moderate or low volatility, meeting the VOC control index; (5) safe and non-toxic to plants, safe to the soil, water, atmosphere and other environments, easy to degrade, will not produce residual pollution or metabolize into other toxic and harmful products; (6) moderate freezing point, good fluidity at room temperature or even at a suitable low temperature, and not easy to solidify. The solvents for the liquid preparations of urease inhibitors disclosed in the prior art are mainly concentrated on dimethyl sulfoxide, N-methyl (alkyl) pyrazolidinone, N,N-dimethylformamide, dioxolane compounds, glycols and derivatives, ether alcohols, amine alcohols, amine solvents, heterocyclic alcohol solvents, alkyl lactates, etc. However, dimethyl sulfoxide and heterocyclic alcohol solvents are usually expensive, N,N-dimethylformamide has potential biological toxicity, and dioxolane compounds and amine solvents are easy to deteriorate, so new solvent systems need to be studied. Summary of the Invention

[0005] In order to overcome the above-mentioned defects of the prior art, the present invention provides a liquid preparation containing a urease inhibitor and its application.

[0006] The liquid preparation comprises the following components in parts by weight:

[0007] Urease inhibitors: 16-36,

[0008] Solvent: 41-150,

[0009] Cosolvent: 3-14,

[0010] Regulator: 0.6-3,

[0011] Wherein, the urease inhibitor is N-n-butylthiophosphoric triamide;

[0012] The solvent is one or a mixture of more than one of chain or cyclic ketones having 3 to 7 carbon atoms;

[0013] The cosolvent is one or a mixture of more than one diol or triol derivatives;

[0014] The regulator is one or a mixture of triethanolamine, diethanolamine, or alkyldiethanolamine having an alkyl group with 1 to 4 carbon atoms.

[0015] Preferably, the weight percentage of the urease inhibitor is 9% to 40%.

[0016] Preferably, the solvent is one or a mixture of more than one of cyclohexanone, cyclopentanone, cycloheptanone, butanone, acetone, 2-pentanone, 3-pentanone, ethyl 3-ketobutyrate, methyl 3-ketobutyrate, propyl 3-ketobutyrate, isopropyl 3-ketobutyrate, and diacetone alcohol.

[0017] More preferably, the solvent is one or a mixture of more than one of cyclohexanone, cyclopentanone, butanone, acetone, 3-butanone ethyl ester, and diacetone alcohol.

[0018] Preferably, the cosolvent is ethylene glycol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, 1,2-propylene glycol, 1,3-propylene glycol, 1-methoxy-2-propanol, 1-ethoxy-2-propanol, 1-propoxy-2-propanol, 1-methoxy-3-propanol, 1-ethoxy-3-propanol, 1-propoxy-3-propanol, 1,4-butanediol, 1-methoxy-4-butanol, 1-ethoxy-4-butanol, 1-propoxy-4-butanol, 1,3-butanediol, 2,3-butanediol, or glycerol, or a mixture of more than one.

[0019] More preferably, the cosolvent is one or a mixture of more than one of ethylene glycol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, 1,2-propylene glycol, 1,3-propylene glycol, 1-methoxy-2-propanol, 1-ethoxy-2-propanol, 1-propoxy-2-propanol, 1-methoxy-3-propanol, 1-ethoxy-3-propanol, 1-propoxy-3-propanol, 1,4-butanediol, and glycerol.

[0020] Preferably, the cosolvent is one or a mixture of more than one of triethanolamine, diethanolamine, methyldiethanolamine, n-propyldiethanolamine, isopropyldiethanolamine, and n-butyldiethanolamine.

[0021] More preferably, the regulator is triethanolamine or diethanolamine.

[0022] Use of any of the above-mentioned liquid preparations containing urease inhibitors in fertilizers.

[0023] The liquid preparation containing the urease inhibitor of the present invention has the following beneficial effects:

[0024] The preferred main solvent, co-solvent and regulator form a synergistic effect (since the urease inhibitor is a highly polar substance, the use of a highly polar ketone solvent can conveniently dissolve the active substance. At the same time, the co-solvent with hydroxyl groups can not only increase the solubility through intermolecular hydrogen bonding, but also improve the flow performance of the system at different temperatures. In view of the physical and chemical properties of the urease inhibitor, the selective addition of the regulator can effectively improve the stability of the active substance in the system and improve its compatibility in fertilizer applications). The liquid preparation containing the urease inhibitor prepared therewith has good solubility and anti-coagulation properties at room temperature and low temperature, and can be stably present at both room temperature and high temperature. When applied to fertilizer, the fertilizer does not dissolve and does not clump. DETAILED DESCRIPTION

[0025] The following part is a specific implementation method to further illustrate the present invention, but the following implementation method is only a further explanation of the present invention and does not mean that the scope of protection of the present invention is limited to this. Any equivalent replacement made based on the ideas of the present invention is within the scope of protection of the present invention.

[0026] 1. Prepare liquid preparations

[0027] N-n-butylthiophosphoric triamide, solvent, cosolvent and regulator were added to a reaction kettle and mixed evenly to obtain examples and comparative examples of liquid solutions. The liquid formulas are shown in the following table.

[0028]

[0029]

[0030] 2. Clarity test at room temperature

[0031] The prepared liquid formulations of Examples 1-0 to 1-21 and Comparative Examples 2-1 to 2-6 were stored in sealed containers at 25° C. for 1 week, 2 weeks, 4 weeks, 2 months, and 3 months, and the properties of the samples were visually examined.

[0032] The observation results showed that liquid formulations 1-0 to 1-21 remained clear solutions at different storage periods, with no solid crystals or precipitation. This indicates that NBPT has good solubility in this solvent system.

[0033] Observation results showed that liquid formulations 2-1, 2-2, 2-4, and 2-5 remained clear solutions at different storage periods, with no solid crystals or precipitation. However, formulations 2-3 and 2-6 changed color from initially colorless and transparent to brown-black. Therefore, formulations 2-3 and 2-6 are not suitable for NBPT formulations.

[0034] 3. Clarity test under low temperature conditions

[0035] The prepared liquid formulations of Examples 1-0 to 1-21 and Comparative Examples 2-1 to 2-6 were stored in sealed containers at 0° C. for one week, and the properties of the samples were visually examined.

[0036] Observation results showed that the liquid formulations of Examples 1-0 to 1-21 were clear solutions at different storage periods, with no solid crystals or solid precipitation. This indicates that NBPT exhibits good solubility and anti-coagulation properties in this solvent system.

[0037] The observation results showed that solids precipitated from the liquid formulations 2-1, 2-2, 2-4, and 2-5. Therefore, the formulations 2-1, 2-2, 2-4, and 2-5 are not suitable for NBPT preparations.

[0038] 4. Loss test under normal temperature conditions

[0039] The prepared selected liquid formulation examples and comparative examples were stored in a sealed state at 25 degrees Celsius for 15, 30, 60 and 90 days, and the mass percentage of NBPT in each liquid composition was determined by HPLC.

[0040]

[0041] From the above results, it can be seen that, except for individual detection errors, the NBPT content in the examples is reduced at room temperature, but the loss rate is less than 2%, indicating that NBPT can be stably stored for a long time in this formulation system.

[0042] The performance of the preparation of Comparative Example 2-1 was similar to that of the embodiment. Comparative Example 2-2 was significantly degraded under room temperature conditions, and the color of Comparative Example 2-3 changed from the initial colorless and transparent to brown-black.

[0043] 5. Accelerated loss test under high temperature conditions

[0044] The prepared selected liquid formulation examples and comparative examples were stored in a sealed state at 45° C. for 7, 15, 30 and 60 days, and the mass percentage of NBPT in each liquid composition was determined by HPLC.

[0045]

[0046]

[0047] From the above results, it can be seen that the content of NBPT in the examples is reduced under high temperature conditions of 45°C, but the loss rate is less than 5%, indicating that NBPT in the formulation system of the examples can exist stably at high temperatures.

[0048] The performance results of the preparation of Comparative Example 2-1 are similar to those of the embodiment. Comparative Example 2-2 degrades rapidly under high temperature conditions of 45°C, and the color of Comparative Example 2-3 changes from the initial colorless and transparent to dark black.

[0049] 6. Application of liquid fertilizers

[0050] fertilizer Recipe Number kg / ton NBPT urea 1-21 4 Compound fertilizer (18-18-18) 1-21 3.2 Compound fertilizer (15-15-15) 1-20 2.7 Nitro compound fertilizer 1-21 3.0

[0051] In all cases, the liquid formulation applied evenly to the fertilizer. No part of the fertilizer dissolved and no lumps formed during application, drying and storage.

Claims

1. A liquid preparation containing a urease inhibitor, characterized in that: The liquid preparation comprises the following components in parts by weight: 16-36 of a urease inhibitor, 41-150 of a solvent, 3-14 of a cosolvent, and 0.6-3 of a regulator; wherein the urease inhibitor is N-n-butylthiophosphoric triamide; the solvent is selected from cyclohexanone, cyclopentanone, butanone, acetone, 3-butanone ethyl ester, or diacetone alcohol; the cosolvent is selected from ethylene glycol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, 1,2-propylene glycol, 1,3-propylene glycol, 1-methoxy-2-propanol, 1-ethoxy-2-propanol, 1-propoxy-2-propanol, 1-methoxy-3-propanol, 1-ethoxy-3-propanol, 1-propoxy-3-propanol, 1,4-butanediol, or glycerol; and the regulator is selected from triethanolamine or diethanolamine.

2. The liquid preparation containing a urease inhibitor according to claim 1, characterized in that: The weight percentage of the urease inhibitor is 9-40%.

3. Use of the liquid preparation containing the urease inhibitor according to claim 1 or 2 in fertilizer.

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