Chemistry: fertilizers – Processes and products – Organic material-containing
Reexamination Certificate
1999-03-22
2001-12-18
Langel, Wayne (Department: 1754)
Chemistry: fertilizers
Processes and products
Organic material-containing
C071S034000, C071S058000, C071S061000, C071S902000, C071SDIG002
Reexamination Certificate
active
06331198
ABSTRACT:
FIELD OF INVENTION
Chemical fertilizers are essential for obtaining high yields in agriculture. Nitrogen fertilizers like urea show low efficiencies when applied to field crops and contribute to environmental pollution. One such nitrification inhibitor, benzotriazole showed increased efficiency when combined with metal ion chelating compounds.
BACKGROUND OF INVENTION
Nitrification inhibitors are useful in reducing nitrogen fertilizer requirement, improving crop yields and quality, reducing nitrogen losses, minimizing environmental pollution and increasing fertilizer use efficiency (Prasad, R. and Power, J. R. 1995. Nitrification inhibitors in agriculture, health and environment. Advances in Agronomy 54: 233-281). Benzotriazole was one of the heterocyclie compounds shown to inhibit nitrification of (NH
4
)
2
SO
4
in soils. (Mc Carty, G. W. and Bremner, J. M. 1989. Inhibition of nitrification in soil by heterocyclic compounds Biol. Fertil. Soil, 8(3), 204, 1989). Benzotriazole was shown to inhibit nitrification to different extents depending on its concentration and the soil, thus showing its variable potency depending on the soil. Since benzotriazole is known to form complexes with a number of metal ions the variable potency may be due to the variations in metal ion availability in these soils. High metal ion concentrations in soil solution may render benzotriazole ineffective as a nitrification inhibitor. No method is available for overcoming the difficulty.
OBJECTS OF THE INVENTION
The main objective of the invention is to provide a synergistic composition useful as a nitrification inhibiting additive for ammonia producing fertilizers.
Another objective of the present invention is to provide metal ion chelating agent for maximizing the potency of benzotriazole as a nitrification inhibitor in soils regardless of the metal ion concentrations present in the latter.
SUMMARY OF THE INVENTION
This invention provides a synergistic composition of metal ion chelating agents added to benzotriazole in the proportion 1:2. These agents though do not possess nitrification inhibitory properties, enhance the ability of benzotriazole greatly to inhibit nitrification in soils irrespective of metal ion concentrations in soil solutions.
DETAILED DESCRIPTION OF THE INVENTION
Nitrification inhibitors are useful for amending nitrogen fertilizers to improve crop yields, reduce N losses, to increase fertilizer use efficiency, to reduce nitrate content in food and sometimes to improve quality of agricultural produce. A number of hetrocyclic compounds, including benzotriazole were recently shown to inhibit nitrification in soils. The potency of benzotriazole varied from soil to soil. The applicants have found that certain organic compounds which are known to bind metal ions as chelates synergistically increase the potency of benzotriazole. Whereas, these compounds do not inhibit nitrification by themselves. A mixture of one or more of these compounds with benzotriazole is, therefore, a superior nitrification inhibiting additive for ammonia producing fertilizers than either benzotriazole or a chelating agent separately. The chelating agents prevent deactivation of benzotriazole by reaction of the latter with metal ions present in the soil to form insoluble precipitates.
Accordingly, the present invention provides a synergistic composition useful as nitrification inhibiting additive for ammonia producing fertilizers which comprises benzotriazole (2.5% to 50% by wt % of the ammonium fertilizer) and metal ion chelating agent (1% to 50% by wt % of the ammonium fertilizer).
In an embodiment of the present invention, the metal ion chelating agent may be selected from salicylaldoxime, ethylene diamine, dimethyl glyoxime, cupferron, thiourea, 1-nitroso-2-naphthol, acetyl acetone or any copper and/or nickel ion binding compounds or their precursors or mixtures thereof.
In another embodiment of the present invention, the synergistic composition may be added to, coated on mixed with, blended with or incorporated into urea, ammonium salt or any other ammonium producing fertilizers.
In yet another embodiment of the invention, the product may be optionally used after changing the physical form as a soil applied fertilizer or using the said composition for soil application before, with or after the application of the nitrogen fertilizer for inhibiting nitrification.
Benzotriazole at 2.5 to 50% by weight of urea or ammonium salts and 1.0 to 50% salicylaldoxime, ethylene diamine, dimethyl glyoxime, cupferron, thiourea, 1-nitroso-2-naphthol, acetyl acetone, mixtures of these and/or their precursors, etc., are added to ammonium producing fertilizer and mixed, coated or blended to produce a fertilizer which can be applied to soils. The fertilizer may optionally be converted to a briquette, supergranule etc., before applying. Benzotriazole and the chelating agents may also be applied separately before, during or after the application of the fertilizer. Other compounds such as urease inhibitors may also be included in the fertilizer. Nitrification of fertilizer nitrogen will be retarded more than it would when only benzotriazole is added.
Benzotriazole reacts with most of the metal ions to produce insoluble compounds and thus loses, to varying degrees depending on the ion and its concentration, its ability to inhibit nitrification. The concentration of different metal ions or their availability in soil varies from soil to soil and thus influences the extent to which nitrification is inhibited by benzotriazole. The chelating agents, which have a low affinity for the generally abundant calcium ions in soil but high affinity for transition metal ions such as copper and nickel bind the transition metal ions so that benzotriazole is not precipitated or otherwise inactivated but remains free and effective. This in turn increases the fertilizer use efficiency.
REFERENCES:
patent: 3701645 (1972-10-01), Scott
patent: 4576626 (1986-03-01), Bauer et al.
patent: 5637131 (1997-06-01), Michel et al.
patent: 5951736 (1999-09-01), Grabarse et al.
Chemical Abstracts citation 112:140518, May 1988.*
Chemical Abstracts citation 105:149872, 1986 (No month).*
Brundy and Bremner, “Inhibitation of Nitrification in Soils”, Soil Sci, Soc, Amer. Proc., vol. 37, 1973, pp. 396-398 (no month).
McCarty and Bremner “Inhibitaion of Nitrification in Soil by Heterocyclic Nitrogen Compounds”, Biology and Fertility of Soils Soils, 1989, pp. 204-211 (no month).
Puttanna and Rao, “Determination of Nitrate in Soil by Second Derivative Ultraviolet Spectrometry”, Commun. Soil Sci. Plant Anal., 24(7 & 8), (1993), pp. 737-743 (no month).
Puttanna and Rao, “Modified Method of Nitrite Determination in Soils by Sulphanilic Acid/N-(1-Naphthyl) Ethylenediamine”, Bank 149 -Heft 5, 1986, pp. 517-521 ( no month).
Prasad and Power, Nitrification Inhibitors for Agriculture, Health and the Environment, pp. 233,281 (no date).
Hinds and Lowe, “Application of the Berthelot Reaction to the Determinartion of Ammonium-N in Soil Extracts and Soil Digests”, Commun. In Soil Science and Plant Analysis, 11(5), 1980, pp. 469-475 (no month).
Gowda Nadur Muddanna Nanje
Kumar Sushil
Puttan Krishnamurthy
Rao Eranki Venkata Surya Prakasa
Council of Scientific & Industrial Research
Langel Wayne
Sughrue Mion Zinn Macpeak & Seas, PLLC
LandOfFree
Composition useful as nitrification inhibiting additive for... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Composition useful as nitrification inhibiting additive for..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Composition useful as nitrification inhibiting additive for... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2586201