ZA200301164B - Controlled release urea-formaldehyde liquid fertilizer resins. - Google Patents
Controlled release urea-formaldehyde liquid fertilizer resins. Download PDFInfo
- Publication number
- ZA200301164B ZA200301164B ZA200301164A ZA200301164A ZA200301164B ZA 200301164 B ZA200301164 B ZA 200301164B ZA 200301164 A ZA200301164 A ZA 200301164A ZA 200301164 A ZA200301164 A ZA 200301164A ZA 200301164 B ZA200301164 B ZA 200301164B
- Authority
- ZA
- South Africa
- Prior art keywords
- urea
- formaldehyde
- resin
- solution
- nitrogen
- Prior art date
Links
- 229920005989 resin Polymers 0.000 title claims description 51
- 239000011347 resin Substances 0.000 title claims description 51
- 229920001807 Urea-formaldehyde Polymers 0.000 title claims description 42
- ODGAOXROABLFNM-UHFFFAOYSA-N polynoxylin Chemical compound O=C.NC(N)=O ODGAOXROABLFNM-UHFFFAOYSA-N 0.000 title claims description 33
- 239000007788 liquid Substances 0.000 title claims description 28
- 239000003337 fertilizer Substances 0.000 title claims description 26
- 238000013270 controlled release Methods 0.000 title claims description 14
- WSFSSNUMVMOOMR-UHFFFAOYSA-N Formaldehyde Chemical compound O=C WSFSSNUMVMOOMR-UHFFFAOYSA-N 0.000 claims description 100
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims description 86
- XSQUKJJJFZCRTK-UHFFFAOYSA-N Urea Chemical compound NC(N)=O XSQUKJJJFZCRTK-UHFFFAOYSA-N 0.000 claims description 76
- 239000004202 carbamide Substances 0.000 claims description 73
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 claims description 55
- 229910052757 nitrogen Inorganic materials 0.000 claims description 44
- 239000000243 solution Substances 0.000 claims description 35
- 229910021529 ammonia Inorganic materials 0.000 claims description 27
- 238000000034 method Methods 0.000 claims description 20
- ZLMJMSJWJFRBEC-UHFFFAOYSA-N Potassium Chemical compound [K] ZLMJMSJWJFRBEC-UHFFFAOYSA-N 0.000 claims description 11
- 239000011591 potassium Substances 0.000 claims description 11
- 229910052700 potassium Inorganic materials 0.000 claims description 11
- GZCGUPFRVQAUEE-SLPGGIOYSA-N aldehydo-D-glucose Chemical compound OC[C@@H](O)[C@@H](O)[C@H](O)[C@@H](O)C=O GZCGUPFRVQAUEE-SLPGGIOYSA-N 0.000 claims description 9
- 239000007787 solid Substances 0.000 claims description 9
- WSFSSNUMVMOOMR-NJFSPNSNSA-N methanone Chemical compound O=[14CH2] WSFSSNUMVMOOMR-NJFSPNSNSA-N 0.000 claims description 8
- 235000015097 nutrients Nutrition 0.000 claims description 8
- 238000010438 heat treatment Methods 0.000 claims description 6
- 239000003637 basic solution Substances 0.000 claims description 4
- 238000001816 cooling Methods 0.000 claims description 3
- BHEPBYXIRTUNPN-UHFFFAOYSA-N hydridophosphorus(.) (triplet) Chemical compound [PH] BHEPBYXIRTUNPN-UHFFFAOYSA-N 0.000 claims description 3
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 claims description 2
- 239000011574 phosphorus Substances 0.000 claims description 2
- 229910052698 phosphorus Inorganic materials 0.000 claims description 2
- 235000013877 carbamide Nutrition 0.000 description 68
- 239000000203 mixture Substances 0.000 description 13
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 12
- 238000006243 chemical reaction Methods 0.000 description 11
- 229910019142 PO4 Inorganic materials 0.000 description 7
- NBIIXXVUZAFLBC-UHFFFAOYSA-K phosphate Chemical compound [O-]P([O-])([O-])=O NBIIXXVUZAFLBC-UHFFFAOYSA-K 0.000 description 7
- 239000010452 phosphate Substances 0.000 description 7
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 6
- 230000015572 biosynthetic process Effects 0.000 description 5
- 239000011785 micronutrient Substances 0.000 description 5
- 235000013369 micronutrients Nutrition 0.000 description 5
- 239000000047 product Substances 0.000 description 5
- 150000003672 ureas Chemical class 0.000 description 5
- VHUUQVKOLVNVRT-UHFFFAOYSA-N Ammonium hydroxide Chemical compound [NH4+].[OH-] VHUUQVKOLVNVRT-UHFFFAOYSA-N 0.000 description 4
- 241000196324 Embryophyta Species 0.000 description 4
- 239000000908 ammonium hydroxide Substances 0.000 description 4
- 239000007864 aqueous solution Substances 0.000 description 4
- 239000002585 base Substances 0.000 description 4
- 238000009833 condensation Methods 0.000 description 4
- 230000005494 condensation Effects 0.000 description 4
- 238000009472 formulation Methods 0.000 description 4
- -1 tri-substituted urea Chemical class 0.000 description 4
- WMFOQBRAJBCJND-UHFFFAOYSA-M Lithium hydroxide Chemical compound [Li+].[OH-] WMFOQBRAJBCJND-UHFFFAOYSA-M 0.000 description 3
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 3
- KWYUFKZDYYNOTN-UHFFFAOYSA-M Potassium hydroxide Chemical compound [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 description 3
- 150000001299 aldehydes Chemical class 0.000 description 3
- 150000001412 amines Chemical class 0.000 description 3
- 239000012141 concentrate Substances 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- 150000003141 primary amines Chemical class 0.000 description 3
- 239000000376 reactant Substances 0.000 description 3
- 239000000725 suspension Substances 0.000 description 3
- COSWCAGTKRUTQV-UHFFFAOYSA-N 1,1,3-trimethylurea Chemical compound CNC(=O)N(C)C COSWCAGTKRUTQV-UHFFFAOYSA-N 0.000 description 2
- 238000001644 13C nuclear magnetic resonance spectroscopy Methods 0.000 description 2
- ZMGMDXCADSRNCX-UHFFFAOYSA-N 5,6-dihydroxy-1,3-diazepan-2-one Chemical compound OC1CNC(=O)NCC1O ZMGMDXCADSRNCX-UHFFFAOYSA-N 0.000 description 2
- IKHGUXGNUITLKF-UHFFFAOYSA-N Acetaldehyde Chemical compound CC=O IKHGUXGNUITLKF-UHFFFAOYSA-N 0.000 description 2
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 description 2
- BAVYZALUXZFZLV-UHFFFAOYSA-N Methylamine Chemical compound NC BAVYZALUXZFZLV-UHFFFAOYSA-N 0.000 description 2
- VGGLHLAESQEWCR-UHFFFAOYSA-N N-(hydroxymethyl)urea Chemical compound NC(=O)NCO VGGLHLAESQEWCR-UHFFFAOYSA-N 0.000 description 2
- 238000005481 NMR spectroscopy Methods 0.000 description 2
- GSEJCLTVZPLZKY-UHFFFAOYSA-N Triethanolamine Chemical compound OCCN(CCO)CCO GSEJCLTVZPLZKY-UHFFFAOYSA-N 0.000 description 2
- 239000002253 acid Substances 0.000 description 2
- 239000000654 additive Substances 0.000 description 2
- 239000007795 chemical reaction product Substances 0.000 description 2
- 125000004122 cyclic group Chemical group 0.000 description 2
- 230000002950 deficient Effects 0.000 description 2
- LEQAOMBKQFMDFZ-UHFFFAOYSA-N glyoxal Chemical compound O=CC=O LEQAOMBKQFMDFZ-UHFFFAOYSA-N 0.000 description 2
- 239000004615 ingredient Substances 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 239000000618 nitrogen fertilizer Substances 0.000 description 2
- BWHMMNNQKKPAPP-UHFFFAOYSA-L potassium carbonate Chemical compound [K+].[K+].[O-]C([O-])=O BWHMMNNQKKPAPP-UHFFFAOYSA-L 0.000 description 2
- 159000000001 potassium salts Chemical class 0.000 description 2
- 239000002244 precipitate Substances 0.000 description 2
- 238000002360 preparation method Methods 0.000 description 2
- 239000002689 soil Substances 0.000 description 2
- 238000003860 storage Methods 0.000 description 2
- 238000003786 synthesis reaction Methods 0.000 description 2
- MXZROAOUCUVNHX-UHFFFAOYSA-N 2-Aminopropanol Chemical compound CCC(N)O MXZROAOUCUVNHX-UHFFFAOYSA-N 0.000 description 1
- PIICEJLVQHRZGT-UHFFFAOYSA-N Ethylenediamine Chemical compound NCCN PIICEJLVQHRZGT-UHFFFAOYSA-N 0.000 description 1
- 102100028701 General vesicular transport factor p115 Human genes 0.000 description 1
- 241000238631 Hexapoda Species 0.000 description 1
- 101000767151 Homo sapiens General vesicular transport factor p115 Proteins 0.000 description 1
- 241000283283 Orcinus orca Species 0.000 description 1
- NBBJYMSMWIIQGU-UHFFFAOYSA-N Propionic aldehyde Chemical compound CCC=O NBBJYMSMWIIQGU-UHFFFAOYSA-N 0.000 description 1
- 230000002378 acidificating effect Effects 0.000 description 1
- 239000008186 active pharmaceutical agent Substances 0.000 description 1
- 239000000853 adhesive Substances 0.000 description 1
- 230000001070 adhesive effect Effects 0.000 description 1
- 150000008044 alkali metal hydroxides Chemical class 0.000 description 1
- 150000003868 ammonium compounds Chemical class 0.000 description 1
- 229910021538 borax Inorganic materials 0.000 description 1
- 239000000872 buffer Substances 0.000 description 1
- 239000003518 caustics Substances 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 239000007859 condensation product Substances 0.000 description 1
- 238000006482 condensation reaction Methods 0.000 description 1
- 230000002939 deleterious effect Effects 0.000 description 1
- FGRVOLIFQGXPCT-UHFFFAOYSA-L dipotassium;dioxido-oxo-sulfanylidene-$l^{6}-sulfane Chemical compound [K+].[K+].[O-]S([O-])(=O)=S FGRVOLIFQGXPCT-UHFFFAOYSA-L 0.000 description 1
- 238000004821 distillation Methods 0.000 description 1
- 238000001704 evaporation Methods 0.000 description 1
- 230000008020 evaporation Effects 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 229940015043 glyoxal Drugs 0.000 description 1
- 238000002955 isolation Methods 0.000 description 1
- 230000007774 longterm Effects 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 230000007935 neutral effect Effects 0.000 description 1
- 229920002866 paraformaldehyde Polymers 0.000 description 1
- 239000000575 pesticide Substances 0.000 description 1
- 150000003013 phosphoric acid derivatives Chemical class 0.000 description 1
- 230000008635 plant growth Effects 0.000 description 1
- 229920000642 polymer Polymers 0.000 description 1
- 238000006116 polymerization reaction Methods 0.000 description 1
- 239000011736 potassium bicarbonate Substances 0.000 description 1
- 235000015497 potassium bicarbonate Nutrition 0.000 description 1
- 229910000028 potassium bicarbonate Inorganic materials 0.000 description 1
- 229910000027 potassium carbonate Inorganic materials 0.000 description 1
- 235000011181 potassium carbonates Nutrition 0.000 description 1
- TYJJADVDDVDEDZ-UHFFFAOYSA-M potassium hydrogencarbonate Chemical compound [K+].OC([O-])=O TYJJADVDDVDEDZ-UHFFFAOYSA-M 0.000 description 1
- 239000011541 reaction mixture Substances 0.000 description 1
- 235000015424 sodium Nutrition 0.000 description 1
- 229910000030 sodium bicarbonate Inorganic materials 0.000 description 1
- UIIMBOGNXHQVGW-UHFFFAOYSA-M sodium bicarbonate Substances [Na+].OC([O-])=O UIIMBOGNXHQVGW-UHFFFAOYSA-M 0.000 description 1
- 235000017557 sodium bicarbonate Nutrition 0.000 description 1
- CDBYLPFSWZWCQE-UHFFFAOYSA-L sodium carbonate Substances [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 description 1
- 229910000029 sodium carbonate Inorganic materials 0.000 description 1
- 239000004328 sodium tetraborate Substances 0.000 description 1
- 235000010339 sodium tetraborate Nutrition 0.000 description 1
- QDWYPRSFEZRKDK-UHFFFAOYSA-M sodium;sulfamate Chemical group [Na+].NS([O-])(=O)=O QDWYPRSFEZRKDK-UHFFFAOYSA-M 0.000 description 1
- 230000003381 solubilizing effect Effects 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- BDHFUVZGWQCTTF-UHFFFAOYSA-M sulfonate Chemical compound [O-]S(=O)=O BDHFUVZGWQCTTF-UHFFFAOYSA-M 0.000 description 1
Description
CONTROLLED RELEASE UREA-FORMALDEHYDE LIQUID
FERTILIZER RESINS
13 v w [01] This application claims priority to provisional U.S. Application Ser. No. 60/226,677, filed August 22, 2000, which is hereby incorporated by reference in its entirety.
[02] The invention relates to a controlled release urea-formaldehyde liquid fertilizer resin having a nitrogen level of at least about 28 wt% and a method of preparing the resin.
[03] Urea-formaldehyde based liquid fertilizers have been used for some time to provide nitrogen to the soil. In addition to nitrogen, phosphorous and potassium are considered major nutrients essential for plant growth. Over time, these major nutrients become deficient in the soil because plants use relatively large amounts of such nutrients. In addition to the major nutrients, secondary and micro-nutrients are also needed, but are usually deficient less often and are used in smaller amounts in fertilizer formulations. It is desirable to have a urea-formaldehyde base resin that contains the necessary nitrogen component, is stable, and capable of solubilizing different levels of phosphorus, potassium, and micro-nutrients from various sources while maintaining stability.
[04] In the past, long term stability of high nitrogen (around 30%) liquid vrea- formaldehyde fertilizers was achieved by forming either a high percentage (more than 30%) of cyclic triazone structures or by condensing the urea-formaldehyde resin into small urea-formaldehyde polymer chains.
[05] Several patents issued to Hawkins describe the preparation of urea-formaldehyde . resins having high triazone contents. U.S. Patent 4,554,005 describes a reaction that produces at least about 30% triazone and has a preferred urea, formaldehyde, \ ammonia ratio of 1.2/1.0/0.28. Hawkins further describes preparing 30% nitrogen,
be . © WO 02/16458 PCT/USO1/24992 liquid UF resin (containing 50% controlled release and 50% quick release nitrogen (50/50) by starting with a 28% nitrogen liquid UF resin which is 70% controlled ) release and 30% quick release (70/30) and adding urea. There is only one (70/30) . resin known in the industry which can be used to consistently produce a clear, storage-stable 50/50 resin containing 30% nitrogen by fortification with urea. This product is currently produced by Tessenderlo Kerley Inc. and marketed as N-SURE®.
[06] U.S. Patent 4,599,102 describes a reaction that produces at least about 30% triazone and has a urea, formaldehyde, ammonia ratio of 1.2/1.0/0.5. Both of these resins have a high percentage of ammonia. U.S. Patent 4776,879 describes a reaction that produces at least about 75% triazone in water insoluble forms. This material is then crystallized out and re-dissolved at low solids levels for use. U.S. Patent 4,778,510 describes a reaction that produces at least about 48% triazone. The nitrogen is the useful part of the fertilizer to the plant and thus the higher the percentage of nitrogen, the more efficient the fertilizer.
[07] Other patents describe condensing the resin into small chains. U.S. Patent 4,781,749 to Moore reacts 1.5 to 2.5 mols formaldehyde per mole of urea in the presence of ammonium compounds such as ammonia. This initial mole ratio is below the initial mole ratio of 5 to 4 mols formaldehyde per mole of urea of the present invention. The pH is maintained at near neutral conditions (6.9-8.5) throughout the reaction.
Condensed UF chains have lower solubility than methylolated ureas and could continue to advance, leading to extremely slow release.
[08] U.S. Patent 3,970,625 to Moore et al. describes a process for preparing urea- formaldehyde concentrates for use as slow release fertilizers or as adhesives. Urea and formaldehyde are mixed in a molar ratio of 1/4.4-7.3 with no more than 0.015 wt.% of ammonia present in the urea. The pH is adjusted to 8.8-9.5 and the mixture is heated to 50-60°C for 30-60 minutes. Thereafter, water is removed by distillation under reduced pressure until solids comprise 60-90% of the remaining residue. For producing fertilizers, the residue is heated for another 48 hours at a temperature of 45- \ 50°C.
rt,
[09] U.S. Patent 5,449,394 to Moore relates to liquid non-polymeric controlled-release nitrogen plant food compositions containing the condensation products of one part ammonia, two parts urea and three parts formaldehyde at a base buffered pH slightly above 7. The reaction is accomplished at a temperature of about 100°C for 30-300 1 4 minutes. Water may be removed by evaporation until the nitrogen content of the formulation is between 20 and 30%. The solution is cooled before polymerization producing chains of more than 3 urea moieties can occur.
[10] U.S. Patent 3,677,736 to Formaini describes a process for manufacturing a liquid fertilizer suspension by preparing an aqueous mixture of urea and formaldehyde having a urea to formaldehyde ratio of 1-2:1 (F:U ratio of 0.5-1:1). Ammonia is then added in an amount of 0.3-6 % by weight and the mixture is heated while maintaining the pH in the range of above 7. After heating, the resulting reaction product is diluted with water and an acidic material is added to adjust the pH to 1-4, then the solution is acidified and reheated. The pH is then adjusted to a pH of between 5 and 8.
[11] It is desirable to make a stable urea-formaldehyde resin suitable for fertilizer use that uses significantly less triazone and no acid condensation, and has a higher nitrogen concentration than prior art resins. It is also desirable to have a resin that contains at least 50% controlled release nitrogen and will provide stable solutions with phosphate and potassium salts and other micro-nutrients.
[12] The invention is directed to a method of making a stable urea-formaldehyde resin suitable for fertilizer use which uses significantly less triazone than the Hawkins’ process and no condensation reaction like the Moore processes, has a high nitrogen concentration, and yet is very stable, for instance, for at least two months at 25°C.
[13] In particular, the invention is directed to a urea-formaldehyde liquid resin prepared by ‘ the method comprising:
1D combining formaldehyde, urea, and ammonia in a basic solution at a formaldehyde/urea/ammonia ratio of about 0.6-1/1/0.25-0.35; 2) heating the solution to about 80°C to about 95°C, while maintaining a pH of at , least 7 for at least 45 minutes; 3) cooling the solution to less than about 50°C, and adjusting the pH to about 9.0 to about 10.5; wherein the nitrogen content of the resin is at least about 28 wt% based on 100 % resin solids with about 50 to about 60 wt% of the nitrogen being controlled release and about 40 to about 50 wt% of the nitrogen being quick release.
[14] The fertilizer resin exhibits superior miscibility with various phosphate, potassium, . and micro-nutrient sources while maintaining water clarity and excellent storage stability.
[15] The invention is directed to a controlled release liquid urea-formaldehyde fertilizer prepared from a solution prepared by the reaction of formaldehyde, urea, and ammonia.
[16] The nitrogen level of the urea-formaldehyde resin is at least about 28%, preferably at least about 30 wi%, and more preferably between about 30 and 32 wi%. The final mole ratio of formaldehyde:urea:ammonia is about 0.6-1:1:0.25-0.35. The nitrogen content is about 50 wi% to about 60 wt% controlled release, preferably about 55 to about 60 wt% and about 40 to about 50 wt% quick release, preferably about 40 wt% to about 45 wt%.
[17] Quick release nitrogen refers to free urea. Controlled release nitrogen refers to - substituted urea. Structure I below is a free urea and II-VII are each a substituted urea with IV-VII representing various triazones. :
BS
DL SN ON
. I i m fo 0 0
DS
SN nN Sn nN un 7 et J J § PS
OH N NH, v v \Gi 0 0
AA
H H
VII
[18] The fertilizer of the invention has the ability to solubilize varying concentrations of potassium and phosphate salts while maintaining excellent storage stability. The resin can be prepared in a reactor without isolation and eliminates the need for the end user to add or mix in urea. No acid condensation steps are required in the instant invention. [191 In accordance with the process of the invention:
[20] Formaldehyde, urea, and ammonia are combined in a basic solution at a formaldehyde/urea/ammonia ratio of about 0.6-1/1/0.25-0.35, preferably about 0.7- ‘ 0.9/1/0.25-0.3, and most preferably about 0.8/1/0.27. All or most of the water present comes from UFC and the ammonia source. Water may be added at the completion of . the cook to adjust nitrogen content.
[21] The solution is heated to about 80°C to about 95°C, preferably about 85°C to about 90°C, and held for at least about 45 minutes, preferably about 45 to about 120 ’ minutes, more preferably about 60 to about 75 minutes, to ensure triazone formation and complete reaction of formaldehyde. Approximately 14 to 20% of the urea is in ’ the form of triazone, preferably about 17 to about 20%. The pH level solution is at least 7, preferably about 7.5 to about 10.5, more preferably about 8.5 to about 9.5.
[22] The solution is cooled to less than about 50°C, preferably about ambient temperature and the pH is adjusted to about 9 to about 10.5, preferably about 9.5 to about 10.
[23] The process of the invention provides a urea-formaldehyde resin in which the triazone content, mono-, di-, and tri-substituted urea has been optimized for maximum stability and compatibility with producing stable blends with various phosphate and potassium salts and other micro-nutrients.
[24] The pH may be maintained or adjusted by adding a compound, such as triethanolamine, borax, sodium or potassium bicarbonate, or sodium or potassium carbonate, preferably triethanolamine, at the start of the batch that will buffer the pH of the batch at the desired pH level. Alternatively, the pH may be maintained by addition of any suitable base during the reaction. While any base can be used to increase the pH of the reaction mix, preferably alkali metal hydroxides are used such as potassium hydroxide, lithium hydroxide, and sodium hydroxide. [25) Skilled practitioners recognize that the reactants are commercially available in many forms. Any form which can react with the other reactants and which does not introduce extraneous moieties deleterious to the desired reaction and reaction product can be used in the preparation of the urea-formaldehyde resin of the invention.
[26] Formaldehyde is available in many forms. Paraform (solid, polymerized formaldehyde) and formalin solutions (aqueous solutions of formaldehyde, sometimes , with methanol, in 37 percent, 44 percent, or 50 percent formaldehyde concentrations) are commonly used forms. Formaldehyde also is available as a gas. Any of these . forms is suitable for use in the practice of the invention. Typically, formalin solutions are preferred as the formaldehyde source. In addition, formaldehyde may be substituted in part or in whole with substituted aldehydes such as acetaldehyde and or propylaldehyde. Glyoxal may also be used in place of formaldehyde as may other aldehydes not listed. It is to be recognized that the aldehyde is dissolved (solubilized) ) in water or other appropriate non-reactive organic of any desired or conventional nature, known in the art.
[27] Similarly, urea is available in many forms. Solid urea, such as prill, and urea solutions, typically aqueous solutions, are commonly available. Further, urea may be combined with another moiety, most typically formaldehyde and urea-formaldehyde, often in aqueous solution. Any form of urea or urea in combination with formaldehyde is suitable for use in the practice of the invention. Both urea prill and combined urea-formaldehyde products are preferred, such as Urea Formaldehyde
Concentrate or UFC 85. These types of products are disclosed in, for example, U.S. patents 5,362,842 and 5,389,716.
[28] Commercially available aqueous formaldehyde and urea-containing solutions are preferred. Such solutions typically contain between about 60 and 25 percent formaldehyde and urea, respectively.
[29] A solution having 35% ammonia can be used providing stability and control problems can be overcome. An aqueous solution containing about 28% ammonia is particularly preferred. Anhydrous ammonia may also be used.
[30] In substitution in part or in whole, for the ammonia, any primary amine or substituted primary amine may be used such as methyl amine, monomethanol amine, amino propanol and the like. Further, difunctional amines may be used such as ethylene diamine or any combination of organic amines provided that one primary amine group is available to form the triazone ring. The reaction rates are much faster and more straight forward. Another reactant of interest is sodium sulfamate to make the cyclic p urea sulfonate.
[31] In a preferred embodiment of the invention, the urea-formaldehyde liquid fertilizer resins have a free urea content of 45-55 wt%, a cyclic urea content of 14-20 wt%, a monomethylol urea content of 25-35 wt% and a di/trimethylurea content of 5-15 wt% based on the urea-formaldehyde resin and, based on a 65-75 wt% urea solution, a free urea content of 31.5-38.5 wt%, a cyclic urea content of 9.8-14 wt%, a monomethylol urea content of 17.5-24.5 wi% and a di/trimethylurea content of 3.5-10.5 wt% wherein the rest of the solution is composed of water, ammonia, and formaldehyde.
[32] The urea-formaldehyde liquid resin of the invention may then be used as a fertilizer.
Other additives may be mixed into the liquid fertilizer prior to use such as any of a wide variety of well-known inorganic fertilizer nutrients based on phosphorous and potassium. Suitable nutrients may be obtained from K-Fol, 0-40-53, which is a solution containing 40% phosphate and 53% potassium. A suspension aid may be used such as a humate solution such as K-Tionic. K-Fol and K-Tionic are manufactured/distributed by GBS Biosciences, LLC. Edinburgh, TX.
[33] Pesticides may also be mixed in, e.g., to control weeds and kill insect larvae. Suitable additives are within the skill of the art.
[34] The following examples are for purposes of illustration and are not intended to limit the scope of the claimed invention.
[35] Example 1
[36] Urea and formaldehyde were reacted in the presence of 4.3% ammonia to produce a product having a pH above 7 and containing urea-formaldehyde in a mole ratio of 0.82 (F/U). UFC 85 is an urea-formaldehyde concentrate where 85% of the solution is urea and formaldehyde (25% and 60%, respectively) and 15% is water.
J
. + WO 02/16458 PCT/US01/24992
UFC 85 IEE EA
Formaldehyde (rom UFC)
Urea (om UFO)
Tee | ww | wr | ow
Moka
IE A BN LR
[37] NMR results: 18% of urea is in the form of triazone, 8% of urea is in the form of di/tri-substituted urea, 30% of urea is in the form of mono-substituted urea, and 45% of urea is in the form of free urea.
[38] The resin was synthesized at a pH of between 8.5 and 9.5 to eliminate the possibility of condensation and thus contain water-soluble chains. The mole ratio was optimized to produce the desired di-substituted, mono-substituted and triazone urea formation.
The resin had a large amount of free urea in the solution that is soluble in the triazone formed early in the synthesis.
[39] Example?
[40] The following ingredients were combined by adding in the following order: UFC, first addition of ammonium hydroxide, first addition of urea, second addition of ammonium hydroxide, and second addition of urea. The combination was heated to 85 °C to 90 °C and held for 60 minutes. The pH was monitored every 15 minutes and adjusted as necessary to maintain a pH between 8.6 and 10 using 25% caustic. 4
UFC, 85% 85
Ammonium hydroxide {28
Orca, pil 25.3
Ammonium hydroxide
Urea, prill to adjust pH (Water | Jtoadjust%N
[41] The combination was then cooled to 25 °C and analyzed for % nitrogen and % free urea (by >C-NMR).
[42] Results: %Nitrogen was 29.9; pH was 10.1; %Free urea was 50% which corresponds to <50% quick release. Blends exhibited excellent stability.
[43] Example 3
[44] Urea and formaldehyde were reacted in the presence of 8.4% ammonia to produce a product having a pH above 7 and containing urea-formaldehyde in a mole ratio of 1.01 (F/U).
Weight %
UFC EE ST I
Formaldehyde (fom UFC)
Grea (from UFC)
IL RN RE FA EN
I
: © WO 02/1648 PCT/US01/24992
[45] NMR results: 15% of urea is in the form of triazone, 6% of urea is in the form of : di/tri-substituted urea, 30% of urea is in the form of mono-substituted urea, and 49% of urea is in the form of free urea.
[46] The resin was synthesized at a pH of between 8.5 and 9.5 to eliminate the possibility of condensation and thus contain water-soluble chains. The mole ratio was optimized to produce the desired di-substituted, mono-substituted and triazone urea formation.
The resin had a large amount of free urea in the solution that is soluble in the triazone formed early in the synthesis.
[47] Example 4
[48] The following ingredients were combined by adding in the following order: UFC, first addition of urea, ammonia, and second addition of urea. The combination was heated to 85 °C to 90 °C and held for 60 minutes. The pH was monitored every 15 minutes and adjusted as necessary to maintain a pH between 8.5 and 10 using 25% NaOH.
UFC, 85% to adjust pH
[49] The combination was then cooled to 25 °C and analyzed for % nitrogen and % free urea (by C-NMR).
[50] Results: %Nitrogen was 30.1; pH was 9.8; %Free urea was 49% which corresponds to <50% quick release. Blends exhibited excellent stability.
[S11 Example 5 . [52] The following blended samples were prepared resulting in an 18-4-6 fertilizer formulation where 18 is % Nitrogen, 4 is % Phosphate, and 6 is % Potassium.
Sample Grams Grams Grams
Liquid UF Resin K-Tionic K-Fol 0-40-33 Water | 21 | 35 | 68 | 58
[53] K-Tionic is a 25% humate solution and is a suspension aid for K-Fol. K-Fol 0-40-53 is a solution containing 40% phosphate and 53% potassium.
Sample 1 A urea-formaldehyde fertilizer resin containing 28% nitrogen where 70% of the nitrogen is controlled release and 30% of the nitrogen is quick release.
Sample 2 A 30% nitrogen fertilizer prepared by adding urea at the end of Sample 1
Sample 3 Resin of Example 1
Sample 4 Resin of Example 3
Sample 5 Resin of Example 1
[54] Samples 1 and 2 became very thick and precipitated during the blending process.
Samples 3-5 remained fluid without precipitate for several weeks.
[55] Example 6
[56] The following blended samples were prepared resulting in a 14-0-12 fertilizer formulation where 14 is % Nitrogen; 0 is % Phosphate; 12 is % Potassium. KTS is a 15% potassium thiosulfate solution.
Sample Grams Grams
Liquid UF Resin KTS
IS I SS RE TR
>
Sample 1 A urea-formaldehyde fertilizer resin containing 28% nitrogen where 70% of the nitrogen is controlled release and 30% of the nitrogen is quick release.
Sample 2 Resin of Example 1
Sample 3 A 30% nitrogen fertilizer prepared by adding urea at the end of the resin of Sample 1
Sample 4 Resin of Example 3
[57] Results: Samples | and 3 formed a gelled precipitate. Samples 2 and 4 formed stable, clear blends. [S8] While the invention has been described with respect to specific examples including presently preferred modes of carrying out the invention, those skilled in the art will appreciate that there are numerous variations and permutations of the above described systems and techniques that fall within the spirit and scope of the invention as set forth in the appended claims.
Claims (20)
- We Claim: . 1. A urea-formaldehyde liquid resin prepared by a method comprising: 1) combining formaldehyde, urea, and ammonia in a basic solution at a » formaldehyde/urea/ammonia ratio of about 0.6-1/1/0.25-0.35; 2) heating the solution to about 80°C to about 95°C, and holding while maintaining pH of at least 7 for at least 45 minutes; and 3) cooling the solution to less than about 50°C, and adjusting the pH to about 9.5 to + about 10.5; wherein the hitrogen content of the urea-formaldehyde resin is at least about 28 wi% based on 100 % resin solids and about 50 wt% to about 60 wt% of the nitrogen is controlled release and about 40 wt% to about 50 wt% of the nitrogen is quick release.
- 2. The urea-formaldehyde liquid resin of claim 1 wherein the formaldehyde/urea/ammonia ratio is about 0.7-0.9/1/0.25-0.3.
- 3. The urea-formaldehyde liquid resin of claim 1 further comprising in 2) maintaining the pH at about 7.5 to about 10.5.
- 4. The urea-formaldehyde liquid resin of claim 3 further comprising in 2) maintaining the pH at about 8.5 to about 9.5.
- 5. The urea-formaldehyde liquid resin of claim 1 further comprising in 2) heating the solution to about 85 to about 90°C.
- 6. The urea-formaldehyde liquid resin of claim 1 further comprising in 2) holding the solution for about 45 to about 120 minutes.
- 7. The urea-formaldehyde liquid resin of claim 6 further comprising in 2) holding the solution for about 60 to about 75 minutes.
- 8. The urea-formaldehyde liquid resin of claim 1 wherein the nitrogen content of the resin is at least about 30 wt% based on 100% resin solids.
- 9. The urea-formaldehyde liquid resin of claim 1 further comprising at least one inorganic fertilizer nutrient selected from phosphorous, potassium, or both.
- 10. A method of producing a urea-formaldehyde liquid resin comprising: 1) combining formaldehyde, urea, and ammonia in a basic solution at a formaldehyde/urea/ammonia ratio of about 0.6-1/1/0.25-0.35; 2) heating the solution to about 80°C to about 95°C, and holding while maintaining pH of at least 7 for at least 45 minutes; and cooling the solution to less than about 50°C, and adjusting the pH to about 9.5 to about 10.5; : wherein the nitrogen content of the urea-formaldehyde resin is at least about 28 wi% based on 100 % resin solids and about 50 wi% to about 60 wt% of the nitrogen is controlled release and about 40 wt% to about 50 wt% of the nitrogen is quick release.
- 11. The method of claim 10 wherein the formaldehyde/urea/ammonia ratio is about 0.7-0.9/1/0.25-0.3. :
- 12. The method of claim 10 further comprising in 2) maintaining the pH at about 7.5 to about 10.5.
- 13. The method of claim 12 further comprising in 2) maintaining the pH at about 8.5 to about 9.5.
- 14. The method of claim 10 further comprising in 2) heating the solution to about 85 to about 90°C.
- 15. The method of claim 10 further comprising in 2) holding the solution for about 45 to = about 120 minutes.
- 16. The method of claim 15 further comprising in 2) holding the solution for about 60 to about 75 minutes.
- 17. The method of claim 10 wherein the nitrogen content of the urea-formaldehyde liquid resin is at least about 30 wt% based on 100% resin solids.
- 18. The method of claim 10 further comprising adding at least one inorganic fertilizer nutrient selected from phosphorus, potassium, or both to the urea-formaldehyde liquid resin.
- 19. A urea-formaldehyde liquid resin according to claim 1, substantially as herein described with reference to any of the illustrative examples.
- 20. A method according to claim 10, substantially as herein described with reference to any of the illustrative examples. -16- Amended Sheet 2004-02-20
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US22667700P | 2000-08-22 | 2000-08-22 |
Publications (1)
Publication Number | Publication Date |
---|---|
ZA200301164B true ZA200301164B (en) | 2004-02-12 |
Family
ID=32849338
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
ZA200301164A ZA200301164B (en) | 2000-08-22 | 2003-02-12 | Controlled release urea-formaldehyde liquid fertilizer resins. |
Country Status (2)
Country | Link |
---|---|
AR (1) | AR030460A1 (en) |
ZA (1) | ZA200301164B (en) |
-
2001
- 2001-08-21 AR ARP010103974 patent/AR030460A1/en active IP Right Grant
-
2003
- 2003-02-12 ZA ZA200301164A patent/ZA200301164B/en unknown
Also Published As
Publication number | Publication date |
---|---|
AR030460A1 (en) | 2003-08-20 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
AU2001279250B2 (en) | Controlled release urea-formaldehyde liquid fertilizer resins | |
AU2001279250A1 (en) | Controlled release urea-formaldehyde liquid fertilizer resins | |
US6306194B1 (en) | Controlled release urea-formaldehyde liquid fertilizer resins with high nitrogen levels | |
US4554005A (en) | Triazone fertilizer and method of making | |
CA2645169C (en) | High nitrogen content liquid fertilizer | |
US7513928B2 (en) | High nitrogen liquid fertilizer | |
US7862642B2 (en) | Extended-release urea-based granular fertilizer | |
US4244727A (en) | Urea-formaldehyde solution for foliar fertilization | |
US4599102A (en) | Triazone fertilizer and method of making | |
US11465945B2 (en) | Urea condensation compositions and methods of making the same | |
GB2210380A (en) | Polymethylene urea fertilizer solution | |
US4776879A (en) | Water insoluble triazone fertilizer and methods of making and use | |
US20040168493A1 (en) | Urea-Formaldehyde Plant Nutrient Solution Containing High Levels of Slow Release Nitrogen | |
ZA200301164B (en) | Controlled release urea-formaldehyde liquid fertilizer resins. | |
USRE31801E (en) | Urea-formaldehyde solution for foliar fertilization | |
GB2164929A (en) | Liquid triazone fertilizer composition |