AU3505899A - Liquid concentrate - Google Patents

Description

AUSTRALIA

Patent Act 1990 COMPLETE SPECIFICATION STANDARD PATENT LIQUID CONCENTRATE The following statement is a full description of this invention, including the best method of performing it known to us: Inventors: Jan Teren, Bratislava (SK) Charles Chromicky, Sydney, (AU) LIQUID CONCENTRATE This invention relates to a liquid, multicomponent concentrate of complex plant nutrients and biogenic elements significant to the health of humans and animals, and which are designed for joint applications with mineral and organic fertilizers and crop protection chemicals, for nutrient solutions for soilless hydroponic growing of plants, for seed treatment, as well as for nutrient enrichment of commercial and garden composts and various growing substrates.

10 For some 80 years the attention of scientists all over the world has been turned to a group of trace biogenic elements, so called micronutrients.

:0:0:Although contained in plant and biological tissues in tiny quantities, these are significant through their high biological activity. In the case of plants, the absence of these in the soil solution causes disorders of 15 growth, physiological development and reduced resistance to diseases e and pests. The consequences are lower yields and lower quality of products. Lasting micro-element deficiency in human and animal nutrition leads to detrimental, quite often serious or irreversible changes of health. More than 60 mineral macro- and micro-elements were 20 quantified as permanent parts of biological tissues associated with metabolic processes generating proteins, saccharides, lipids, mineral substances and energy. Living organisms are capable of producing very complex molecules of enzymes and vitamins, however they are not capable of synthesizing the basic building blocks mineral elements.

These must be supplied externally through nutrition.

This is the reason why in the past 40-50 years alongside with fertilization with basic nutrients, secondary nutrients and micro-elements are being applied.

As a consequence of intensified agricultural production the deficiency of micro-elements in plants is more and more obvious. Consecutively there is a deficiency of these in the bodies of animals and humans.

Microelement nutrition is becoming more dominant, especially because: m New highly effective varieties of plants through their higher yields drain the soil of more micro-nutrients than the natural slow process of rock weathering can supply.

a To reduce transport, storage and handling costs, high concentration industrial fertilizers are preferred. These are manufactured from selected, purer chemical compounds. The classical, low grade fertilizers which contain large quantities of micro-elements are no longer used.

S 10 The new technologies of stock and other animals breeding reduced the amount of generated and applied organic fertilizers, which are another source of micro-elements.

A significant reduction of micro-element uptake is caused by some agricultural practices which cause degradation of micro-nutrients.

These are excessive use of lime or phosphorus fertilizers, uneven application of fertilizers, etc.

Consequently, the consumption of micro-nutrients is growing especially in developed countries. To demonstrate the consumption of microelements shown are the quantities sold for plant nutrition in the USA 20 (Statistical Reporting Service -1997. Consumption of Commercial Fertilizers in the U.S. USDA-SEA, Washington, DC): Years Quantity of plant micro-nutrient sold in the U.S.

(in thousands metric tones) Cu Fe Mn Mo Zn 1970-1971 0.9 2.2 11.8 0.03 15.0 1976-1977 0.8 2.4 15.1 0.07 16.5 Sources of micronutrients are usually inorganic salts, various industrial wastes and by-products, treated minerals, micro-element frits but also various natural and synthetic complexes and chelates.

Synthetic complexes and chelates are created through reactions of various complexing and chelating agents with cations of metals, which are bound by coordination bonds.

Chelates are the most effective source of micro-elements.

In 1893 Alfred Werner in his study of the structure of metallic complexes showed for the first time the cyclic structure of such complexes with ethylene diamine. In 1920 Morgan and Drew introduced the name of chelate for the complexing part of the molecule so called ligand, as for example ethylene diamine with two donor atoms binding to one metallic 10 atom, creating a cyclic structure.

Many more ligands containing more than two donor atoms and binding the central atom of metal by multiple cyclic bonds were found later. This type of metallic complexes can be created, if the metal atom possesses free orbitals and reacts with ligand containing donor atoms with 15 uncoupled electrons.

In most of the currently manufactured and used chelates the donor atoms are nitrogen or oxygen.

A metal chelate was used for plant nutrition for the first time probably in 1949 by Jacobson.

20 Since then a large number of chelates based on a number of different chelating substances have been synthesized. Generally it can be stated that chelate complexes containing five- or six-atom cycles are more stable than similar complexes missing chelate cycles.

The chelate agents most studied in association with plant nutrition can be divided into two groups: aminopolycarboxylates and hydroxycarboxylates. The names are indicative of their nature derivatives of organic carboxylic acids.

Examples of aminocarboxylates are: EDTA (ethylene diamine tetraacetate), HEEDTA (hydroxyethyl ethylene diamine acetate), DTPA (diethylene triamine pentaacetate) and EDDHA (ethylene diamine di(ohydroxyphenyl acetate)).

The representatives of hydroxycarboxylate chelating agents are for instance: sugars and their derivatives, citric acid, tricarboxylates, dicarboxylates, gluconic acid, monocarboxylates, glucoheptonic acid, and other mono- and polycarboxylates.

Chelating agents are mostly used not as free acids but usually as their sodium or potassium salts.

Stability of chelates depends on a number of conditions mainly it depends on the properties of the central ion or ligand, pH, environment, concentration of the chelate and temperature.

The stability is usually expressed by the stability constant, which is a numeric expression of the chemical equilibrium in the system: Metal Chelating Agent Chelated Metal 15 The stability constant is then expressed as: [Chelated Metal] SK= [Metal] x [Chelating Agent] The constant is usually expressed in the form of a common logarithm of K. The higher the constant, the more stable the respective chelate.

Recently, the attention of research workers has been focused on the impact of the stability of various chelates on their agricultural efficiency.

The following is highly remarkable data presented by Arthur Wallace (Wallace, "A Decade of Synthetic Chelating Agents in Inorganic Plant Nutrition", Edwards Brothers, Inc Ann Arbor, Michigan, "Regulation of the Micronutrient Status of Plants by Chelating Agents and Other Factors", Edwards Brothers, Inc Ann Arbor, Michigan, "A One-Decade Uptake on Chelated Metals for Supplying Micronutrients to Crops" J. Plant Nutrition 6/6/:429).

The published data shows, that whilst the aminopolycarboxylate type chelates are generally more efficient in slightly acidic environment, the hydroxycarboxylate type gluconates and glucoheptonates) are more efficient in most soil applications. This is obviously related to their higher stability in slightly basic environment. In terms of their practical use the significant factors are their lower price and their environmental impact, since these are usually natural substances manufactured through enzyme technologies (Sisniasvili, Gogudze a Khorlin Chem.

Abstr. 1976, 84: 74545 n, Gray, K. US Patent 4181516, Chem. Eng.

S 10 News 61: 451, 1983).

Generally, by using a hydroxycarboxylate type of chelate it is possible to reduce costs of agricultural products and at the same time increase their nutritional value.

Use of chelates for micronutrient nutrition in agriculture, mainly in 15 developed countries became quite common despite the fact that the Scosts compared to normal inorganic sources are between 5 to 100 times higher (Mortverdt, J.J: "Micronutrient fertilizer technology and use in the United States", TVA-NFDC, Muscle Shoals, Alabama USA Paper presented at the Seminare on Micronutrients in Agriculture, New Delhi, 20 India, September 17-21, 1979).

These facts can be documented by price differences of different sources of micronutrients published in 1979 and 1990 for zinc as a selected micronutrient: Source of Zn Price in USA Reference (US$/kg Zn) ZnSO 4

H

2 0 1.39 1 ZnSO 4

H

2 0 1.59 1 ZnO 0.62 1 Zn EDTA 18.35 1 Zn EDTA 21.76 2 Zn EDTA 33.85 2 Zn GLA 8.79 2 g-granulate, p-pulver, I-liquid, s-solid, GLH- Glucoheptonate Mortvedt, Micronutrient fertilizer technology and use in the United States", TVA- NFDC, Muscle Shoals, Alabama, USA, Paper presented at the India/ FAO/Norway Seminar on September 17-21, 1979.

S 10 Clemens, Whitehurst, G. "Chelates in agriculture", Fertilizer Research 25: 127-131, 1990.

Application of chelated micronutrients, however has a number of advantages when compared to the traditional inorganic sources: a Protection of a soil applied micronutrient against its degradation and consequently its improved utilization and faster action, a possibility of combination with other agrochemicals in the presence of which precipitation normally occurs combination of micronutrients with liquid fertilizers containing phosphates, combination with crop 20 protection chemicals pesticides, water solutions with higher :carbonate content etc.) chelated form promotes a systemic action of micronutrients through foliar application, significant broadening of the pH range for a biologically efficient application of micronutrients.

It is obvious, that chelated forms of micro-nutrients are a widespread form for the manufacture of modern, highly efficient sources of plant nutrients.

Chelated trace elements are common constituents of a number of special solid, but mainly liquid fertilizers for both soil and foliar plant nutrition (Wuxal, Complesal, Harmavit, Damisol, Nutri-Flo and others).

Apart from a number of products which supply one or several microelements, there are multicomponent concentrates containing more or all basic micro-elements for plant nutrition.

To achieve the highest possible stability of chelates in these products, the aminopolycarboxylate form of chelating agents is preferably used.

Examples are derivatives of ethylenediaminetetraacetic acid (EDTA), diethylenetriaminepentaacetic acid (DTPA), hydroxyethylenediaminetriacetic acid (HEEDTA), ethylenediaminedi(ohydroxyphenylacetic) acid (EDDHA) and some others.

Some of the multi-component concentrates are Multimicro, a paste concentrate manufactured by a German company Hoechst AG, Mikrochela and Mikrochela Special produced by a Slovak company Agrichem, Mikrola-A made in the Czech Republic, Multiplex concentrates manufactured by a US company Rohm Haas, concentrates Claw-El 15 manufactured by a US company Brandt, and some other products.

Despite the high efficiency of the mentioned multicomponent concentrates, their common disadvantage is their aminopolycarboxylate chelating agent. These chelating agents belong to a group of typical synthetic chemicals, which are typically not naturally occuring and are 20 quite difficult to break down.

As previously mentioned, these types of chelates have the highest stability in an acidic environment. Their stability reduces dramatically at a pH higher than 7. This is why they are less efficient for example in eliminating the deficiency of iron in carbonaceous soils, where the chelates based on hydroxypolycarboxylic acids are more efficient.

High relative molecular weight of chelating agents, which act as ligands, is the reason for a significant dilution of the central atom in the molecule of the final chelate and hence a low concentration of the nutrient in the product.

In the case of liquid concentrates, the requirement of the highest possible concentration of chelated elements is controlled by the limited solubility of the chelate itself as well as of the solubility of by-products of complexing reactions. Mass usage of the multicomponent concentrates based on derivatives of aminopolycarboxylic acids is to a certain extent restricted by a high price of the chelating agents.

Currently manufactured concentrates of secondary nutrients and trace elements satisfy the needs of plants to a certain extent. However, they do not address the supply of some further elements important for health of humans and animals into their food chain.

Despite the fact that in the late eighties selenium (Se) was recognized as an important biogenous element for humans and animals, this element is usually not contained in the micro-element concentrates for plant .:nutrition.

In the case of selenium, the health research showed, that its deficiency increases the risk of cardiovascular diseases. One of the functions of S 15 selenium in the human body is the inhibition of auto-oxidation of lipids. It was also proven, that selenium reduces toxicity of some heavy metals (cadmium, mercury, etc.). Researchers also found, that selenium inhibits aging of tissues and significantly supports the immune system.

Hence selenium should be built into the plant metabolism to increase its content in the food for humans and animals.

S We have now found, that most of the disadvantages of the known multicomponent concentrates of complex plant nutrients can be effectively overcome by manufacture and use of a liquid multicomponent concentrate of complex plant nutrients and biogenic elements significant to the health of humans and animals according to the present invention.

The concentrate is designed mainly for joint applications with mineral and organic fertilizers and crop protection chemicals, for nutrient solutions for soilless hydroponic growing of plants, for seed treatment, as well as for enrichment of commercial and garden composts and various growing substrates by plant nutrients and biogenic elements.

For the multicomponent concentrate according to the present invention it is typical, that 1 liter of said undiluted concentrate comprises: to 45 g of iron (as Fe) and 4g to 30 g of zinc (as Zn), and/or manganese (as Mn), and/or copper (as Cu), and/or boron (as B), and further 5 mg to 350 mg of selenium (as Se), and may also contain nitrogen and/or sulfur and/or magnesium and/or calcium and/or molybdenum and/or cobalt (Co), and/or iodine and/or titanium and in which the complexing agent 10 for the complex compounds is 2-hydroxypropane-l,2,3-tricarboxylic acid, so called citric acid (C 6

H

8 0 7 and/or ammonium, and/or alkali salts :.**.thereof. The alkali salts of said acid are mostly sodium and potassium salts.

The liquid, multicomponent concentrate according to the invention have 15 a character of a solution, or a colloid solution or a suspension or a gel.

A significant advantage of the concentrate according to the solution is that the complexing agent, 2-hydroxy-1,2,3-tricarboxylic acid, so called citric acid is a substance almost exclusively manufactured by a biotechnological process, by fermentation of diluted acidified sugar 20 molasses by Aspergilus Niger fungus. This implies that citric acid is a natural substance, generally available and readily biodegradable.

Although the chemical stability of chelates contained in the liquid concentrate according to the invention is lower than that of aminopolycarboxylate types of chelates, it is sufficient for said liquid concentrate to meet all application requirements. Those are joint application with liquid fertilizers and crop protection chemicals, protection of the biogenic elements against degradation, fast and effective action through foliar application suitability for nutrient solutions for hydroponics soilless growing of plants etc. The advantage of said liquid concentrate compared to aminopolycarboxylate types is that they are more stable and hence more efficient in neutral or slightly basic solutions, which is significant mainly in soil applications for elimination of chlorosis caused by deficiency of iron and some other elements, mainly in carbonaceous soils).

Another advantage of said liquid concentrate is that despite a high number of components, by a suitable sequence of manufacturing an unusually high concentration of active components is achieved whilst the concentrate maintains a solution character, a relatively high phase stability and compatibility with other agrochemicals.

An advantage is the accessibility and low price as well as good 10 occupational health and safety associated with the use of citric acid and its ammonium and alkali salts compared to most aminopolycarboxylate chelating agents.

It is characteristic of said liquid concentrates that alongside with other plant nutrients and biogenic elements significant to the health of humans I and animals, they always comprise selenium (Se) and the concentration S"of selenium is 5 mg to 350 mg per one liter of undiluted liquid concentrate. Selenium in said liquid concentrates is present in a form suitable for plant uptake.

A further important advantage of said liquid concentrate is its simple way of manufacturing and a low demand for process equipment.

Examples The invention is now illustrated but is not limited to the following examples, in which all percentages are expressed on a weight basis.

Example 1 By reacting the appropriate amounts of sulphates of zinc, manganese, copper, cobalt, iron and titanium, and boric acid, ammonium molybdate, sodium selenite and potassium iodide in a water solution with ammonia and citric acid, a liquid multicomponent concentrate according to the invention was prepared. The reaction was carried out in a stirred mixing tank. The product had a neutral chemical reaction and an appearance of a viscous syrupy brown-red solution. It comprised: 1.65%, or 21.4 g of iron (as Fe) in 1 liter, 1.10%, or 14.2 g of zinc (as Zn) in 1 liter, 1.10%, or 14.2 g of manganese (as Mn) in 1 liter, 10 1.10%, or 14.2 g of copper (as Cu) in 1 liter, 0.55%, or 7.1 g of boron (as B) in 1 liter, 0.013% or 0.17 g of cobalt (as Co) in 1 liter, 0.026%, or 0.34 g of molybdenum (as Mo) in 1 liter, 0.0095%, or 0.123 mg of selenium (as Se) in 1 liter, 15 0.016% or 0.207 g of iodine (as I) in 1 liter, 0.043%, or 0.557 g of titanium (as Ti) in 1 liter of concentrate.

Further it comprised: S 20 6.28%, or 81.3 g of nitrogen as ammonium in 1 liter, and 2.69%, or 34.8 g of sulfur in a plant acceptable form in 1 liter of concentrate.

Its specific gravity was 1297 kg/m 3 at 20 0

C.

The liquid multicomponent concentrate was used for plant nutrition as a 0.15% to 0.25% water solution in the following doses: Cereals in the phase of stem formation 3.0 I/ha Cereals in the phase of ear formation 8.0 I/ha Potatoes 1.3 -3.0 I/ha Corn 3.0 I/ha Canola 1.5 -3.0 I/ha Vegetables Fruit trees Wine grapes 2.0 -3.0 I/ha 2.0 -5.01I/ha 3.0 -5.0 I/ha 0s 0 0 U SO *0

U

000 0 0000 0000

S

555 SO SO 4 5 0955

U.

S. S S S 0* S 95 *S 595.

55..

S

*555 9.

SOSS

5.55..

The concentrate was a suitable source of micronutrients for fertigation as well as for hydroponic growing of plants.

Claims (2)

1. A liquid, multicomponent concentrate of complex plant nutrients and biogenic elements significant for health of humans and animals, which is designed mainly for joint applications with mineral and organic fertilizers and crop protection chemicals, for nutrient solutions for soilless hydroponic growing of plants, for seed treatment, as well as for nutrient enrichment of commercial and garden composts and S..o 10 various growing substrates and which if undiluted comprises in 1 liter: ooo 10g to 45 g of iron (as Fe) and 4g to 30 g of zinc as Zn), and/or manganese (as Mn), and/or copper (as Cu), and/or boron (as B), and further 5mg to 350 mg of selenium (as Se), 15 and may also contain nitrogen and/or sulfur and/or *o magnesium and/or calcium and/or molybdenum (Mo), and/or cobalt and/or iodine and/or titanium and in which 0 the complexing agent for the complex compounds is

2-hydroxypropane-1,2,3- tricarboxylic acid, so called citric acid 20 (C 6 H 8 0 7 and/or ammonium, and/or alkali salts thereof. S 2. The liquid, multi-component concentrate of claim 1 which has a character of a solution, or a colloid solution or a suspension or a gel.