CS272872B1 - Method of agent production for nitrifying bacteria function inhibition - Google Patents

Abstract

The invention concerns the method of production of an agent for inhibition of the function of nitrifying bacteria. Its basis is the condensing reaction of calcium cyanamide, CaCH2, with at least one of the substances occurring with a calcium cation present in the system of at least one low-soluble electrolyte, where the value of the negative common logarithm of the solubility product (pK) at 15 to 30 degrees C is 1.2 to 38. The condensing chemical reaction occurs in the form of a suspension containing 2 to 41 % by weight of dry matter, at a temperature of 10 to 75 degrees C, particularly 25 to 60 degrees C, in an environment of water and/or in an environment of a polar organic solvent. As the substance occurring with a calcium cation of the low-soluble electrolyte, ethanedioic acid and/or sulphuric acid and/or carbon dioxide and/or hydrofluoric acid and/or hexafluorosilicic acid is used. The result of the condensing react is that the expelled low-soluble electrolyte is separated from the reaction product forming a liquid phase by sedimentation and/or filtration and/or centrifuging, or the expelled coagulant in the liquid phase is stabilised in order to reduce the rate of sedimentation of its particles. The product can also be thickened and/or supplemented with substances modifying the chemical reaction. The invention can be used in chemical production, particularly in connection with the production of agricultural chemicals.

Description

The invention relates to a method. producing a composition for inhibiting the function of nitrifying bacteria.

Exact experiments have found that nitrogen applied in industrial. and organic fertilizers are used by plants at an average of 30 to 40%, and it is now well known that nitrogen losses also cause serious environmental problems (Reports and Conclusions of the 9th CIEC World Conference on Industrial Fertilizers, Budapest, 11- 16 Jun 1984).

In recent years, therefore, considerable attention has been paid to the study of new ways of using nitrogen more efficiently from fertilizers, among which the use of inhibitors of nitrification is a prominent position.

The effect of nitrification inhibitors slows down or, for some time, completely stops the conversion of ammoniacal nitrogen to nitrite nitrogen, allowing the reduction of nitrogen losses by leaching or denitrification, since ammoniacal nitrogen is substantially less mobile than nitrate or nitrite nitrogen .

Ritrification is a biological enzymatic process in which reduced nitrogenous substances are oxidized with a transient release of nitrites and their subsequent oxidation to nitrates. The source of nitrogen for oxidation is mainly ammonium salts (so-called autotrophic nitrification), eventually organic nitrogenous substances (so-called heterotrophic nitrification). These processes are ensured by a specific physiological group of microorganisms - the triaxial microflora, which obtains energy for its life processes through nitrogen oxidation processes.

The energy yield of nitrification is reported to be about 276 kJ per mole and the subsequent nitratation releases a further 73 k per mole (DELVIC, K .: Krugovorot azota. Biosphere, Izd. Mir 1972).

Today, we know several dozen chemical compounds capable of more or less selectively suppressing the activity of nitrifying microflora. For example, 2-chloro-6-trichloromethylpyridine (Ritrapyrin, R-Serve), 4-amino-4H-1,2,4-triazole hydrochloride (ATG), 2-mercapto-1,3,4-triazole (MT ), amidinothiourea (ASU), 2,4-dichloroaniline, R- (2,5-dichlorophenyl) succinimide (DOS), 2-mercaptobenzothiazole (IFt), dicyandiamide (Didin, DGD), 2-amino-4-chloro-6 -methyl-pyrimidine (AJ 1), 2- (4-aminophenylsulfonylamido) thiazole (Cibazole, ST) (HAUGK,

R. D .: '' Mode of Action of Ritrification Inhibitors. Ritrification Inhibitore - Potantials and Limitations. American Society of A.gronomy and Soil Science Society of America, Madison 1980; TOMAR, J. - SOCHA, J .: Efficiency of nitrogen utilization in agriculture - nitrification inhibitors. ”Chemické listy, 75 (1981), p. 743-752; SLARGER, JHG - KERKHOFF, P .: Ritrification Inhibitors in Agriculture and Horticulture: A Review of Literature. Agricultural University, De Drejen 3, 6703 BO Rageningen, Retherlands). LARG, S. et al. recently published results using 1-carbamoil-3 (S) -methylpyrazole (KMP) (Agrochimija,

3, 1935, p. 10-17).

In addition to the use of a wide range of usually complicated compounds. In the 1970s, significantly simpler and more environmentally friendly ”inhibitors of usually inorganic character began to be tested under operating conditions in Western European countries. To Great Britain ASHRORTH, Ď. and collaborators have successfully verified, for example, the use of carbon disulfide (carbon disulphide) to inhibit nitrification (J. Sci. Food Agric. 28, 673-683 (1977)).

T recently, the use of CS ₂ to inhibit nitrification, based on extensive testing, has also been recommended by field biologists of the USSR and Canada (Ohimija v sel. Chozjaj., Vol 22, 2 (1984), pp. 10-14; Plent and Soil 65 (1982), pp. 203-218).

Already from the relatively complicated structures that are common in. The currently used nitrified organic type inhibitors also result in a complicated technology for their production and use, usually from the commercial and economic point of view, with relatively limited raw materials (hydrazine hydrate, β-picoline, pyridine and the like). Some of this group are not usually recommended from the hygienic-health point of view (eg the use of ATG-type triazole preparations is not allowed in the USSR) and the preparation of several of them is a considerable risk.

CS 272 872 B1 2 and demanding from the operational and mechanical-technological point of view (eg dangerous thermal condensation of formtriazole, chlorination of o2-picoline at moderately high temperatures, chlorine-picoline often works with a mixture of chlorine and water vapor, etc.).

It has now been found that by using compounds of an exclusively inorganic nature, compositions useful for inhibiting the function of nitrifying bacteria can be prepared in a technologically undemanding manner.

The principle of the solution is that calcium cyanamide (CaCN ₂ ), in the form of a suspension containing 2 to 41 percent by weight of dry matter, in a water and / or a polar organic solvent environment, is subjected to a precipitation chemical reaction at 10 to 75 ° C with at least one substances providing with at least one sparingly soluble electrolyte with a calcium cation in the system, whose value of the negative decadic logarithm of the product of solubility (pK _g ) in water at 15 to 30 ° C is 1.2 to 38. Excludes sparingly soluble electrolyte from the reaction product forming the liquid phase is separated by sedimentation and / or filtration and / or centrifugation. The precipitated sparingly soluble electrolyte precipitate is stabilized in the liquid phase containing the active ingredient for inhibition so as to reduce the settling rate of the precipitated solid phase particles. The reaction product is optionally further thickened and / or optionally supplemented with substances which modify its chemical reaction - its pH.

It has been experimentally confirmed that ethanedium, a so-called ethaned, electrolyte having a pK _g of 15 to 30 ° C in an aqueous medium at a temperature of 15 to 30 ° C, is used as a substance providing with a calcium cation present in the system. oxalic acid, (COOH) ₂ and / or sulfuric acid and / or carbon dioxide and / or hexafluorosilicic acid, HgSiFg and / or hydrofluoric acid, HF.

For the low-solubility reaction products of these reactions, the literature discloses these solubility product values Κ and. Respectively. negative decimal logarithm of the product of solubility with water:

Zlúčeniaa Solubility product K _g at temperature t (° C) -los K _s = pK _s at temperature t (° C) CaCgO4. H + H 8.58 / 25 ° C (1) 2.10 ^-9 / 18-25 ° C 8.7 / 18-25 ° C (2) 1.78.10 ^-9 / 18 ° 0 - (3) 2.57.10 ^-9 / 25 ° 0 - (4) CaCO ^ 0.87.10 ^-8 / 25 ° C - (3) 5.10 ^-9 / 18-25 ° C 8.3 / 18-25 ° 0 (2) - 8.35 / 25 ° C (ABOUT 8.7.10 ^-9 / 25 ° C - (4) CaSO ^ 6.26.10 ^-5 / 25 ° C - in (4) CaSC ₄ . 2H ₂ O 1.10 ^-5 / 18-25 ° C 5 / 18-25 ° C (2) - 5.04 / 25 ° C (1) CaP ₂ 3.4.10 ^-11 / 18 ° C - (3) 4.10 ^-10 / 18-25 ° C 10.4 / 18-25 ° C (2) - 10.57 / 25 ° C (D

(1) VOHLÍDAL, J. et al .: Chemické tabulky, SNTL - Praha 1985, s. 254–255 (2) EABINOVIČ, V. A. - CHAVIN, Z. Ja .: Brief Chemical Handbook, SNTL - Prague 1985, p. 312 - 313 (3) AlíDEELÍK, K. et al .: Chemické tabulky, SNTL - Bratislava 1967, p. 270 (4) KELLO, V. - TKÁČ, A .: Physical Chemistry, ALFA - Bratislava 1967, p. 447

Furthermore, it has also been found to be advantageous to carry out the precipitation reaction at a temperature of 25 ° C.

CS 272 872 Bl

Course. The chemical reaction in the system under consideration is conditioned by the formation of low soluble calcium compounds. Type CaSO ^, Ca (C00) _2, CaCO ^, pin _2, and the like for the purposes of the following, greatly simplified reaction schemes:

CadTg + h ₂ s ° ₄ = CaSO4 + CN-NH ₂ CaCr ₂ + H00C-C00H - Ca ' ⁰⁰⁰ ~ ^Ga ' 00C + dT-HH ₂ CaCHg + E ₂ C 3 = CaCO ₃ + dT-RH ₂ CaCl ₂ + 2 HP CaP ₂ + chh ₂ , + H ₀ SiP _c 2 H _o 0 = 3 Ca? ' + 3 GIT-1H,

Since the second - major reaction product of the precipitation reactions - cyanamide, depending on the reaction conditions (pH, temperature, temperature exposure, side reactions and degradation products and impurities contained in the raw materials, etc.), is subject to further reactions, the solution according to the invention usually does not give a chemical individe. (cyanamide), but only a mixture of inhaled nitrogen compounds which, according to the above reaction conditions, also contains cyanoguanidine anion, dicyandiamide, imidocarbon imide j - guanidine, urea, thiourea and the like.

The preparation of a composition suitable for inhibiting the function of the nitrifying bacteria according to the invention is illustrated and illustrated in more detail, but in no way limited by the following examples:

Example 1

800 ml of water was charged to a stirrer flask equipped with a stirrer, and 200 g of technical nitrogen lime, a commercial product of Suddeutsche Kalkstickstoff Víerke - Trostberg, AG containing 19.8% of total IT and 55.0% of CaO, were gradually added under stirring. By calculating the total nitrogen content, it was determined that nitrogen lime contained about 56.6% of calcium cyanamide - CadT ₂ ·

After thoroughly stirring, the the of aqueous suspensions lime nitrogen through the dropping funnel gradual, with stirring, was added 908.8 g of 14.3 Ish-acid solution water štaveíovej prepared by dissolving 181.8 g of crystalline Oxalic ^ 2 ^ 2θ4 '2¾ ^{0 T} 727.0 g of distilled water at 40-45 ° C.

The dark gray suspension reaction mixture was heated to 40-50 ° C for about 80 minutes with stirring in a water bath. 38.0 g of ammonium dihydrogen phosphate were added thereto as the reaction mixture was tempered as an additive stabilizing the final product.

Then, the suspension was resolved by vacuum filtration on a Blechner funnel through a filter paper, yielding 1505 ε of a clear filtrate containing 2.68% by weight. total nitrogen and 431 g of a gray gray filter cake.

The filtrate containing about 6.0% of the residue was concentrated using a laboratory rotary vacuum evaporator to about 40 fo of dry matter and was used for agrobiological tests in mixtures with nitrogenous liquid fertilizers based on NH 4 ITO 4 and urea.

Example 2

Into a flask equipped with a stirrer was charged 735 g of 20% technical hexafluorosilicic acid HgSiFg obtained in connection with the production of solid phosphate fertilizers. The acid was preheated to 40 ° C with a water bath and then 425 E technical grade lime of the same quality as in Example 1 was added gradually with stirring.

50.0 g of 10-34-0 polyphosphate fertilizer liquid nitrogen-phosphorus fertilizer was added to the reaction mixture as a stabilizing additive buffer.

The reaction mixture was allowed to warm to the above temperature for about 1 hour with stirring.

Then the reaction mixture was separated by filtration. 720 g of a clear filtrate were obtained which contained

% Of CS 272'872 B1 4 val 7.35 wt. % nitrogen and 1.4 wt. P ₂ ^O 5 'contained about 12.6 wt. residue.

The wet filter cake consisted of Ca 2+, SiO _2, and unreacted nitrogen lime residues. The clear filtrate prepared above was concentrated to about 42% solids content using a laboratory rotary evaporator, yielding 216 g of a liquid composition intended to inhibit the function of nitrifying bacteria.

Example 3

To a sulfonation flask equipped with a stirrer and a thermometer, 388.2 g of distilled water was charged, and 141.5 g of technical nitrogen lime were gradually added under stirring, resulting in a temperature rise of 18 ° C to about 30 ° C. 102.2 g of sulfuric acid containing 96% of H ₂ SO 4 monohydrate was added to the prepared aqueous suspension via an addition funnel with efficient stirring.

The rate of H 2 SO 4 addition was controlled so that the temperature of the reaction mixture did not exceed 40 ° C. After all the acid was added, the pH of the reaction mixture was adjusted to pH 4.5-5.0 by the addition of phosphoric acid.

Filtration of the reaction mixture yielded 195 g of a filtrate containing 7.0% by weight of total nitrogen. The weak acid reaction filtrate, after concentration by evaporation under reduced pressure, was used for microbiological assays for inhibition of nitrifying soil processes.

Claims (3)

Process for the manufacture of a composition for inhibiting the function of nitrifying bacteria, characterized in that calcium cyanamide, CaCNg, is in the form of a suspension containing 2 to 41% by weight of dry matter in a water and / or polar organic solvent environment at a temperature of 10 to 75 ° C undergoes a precipitation chemical reaction with at least one of the substances providing with the calcium cation present in the system at least one sparingly soluble electrolyte whose negative decadic logarithm of the solubility product (pK _g ) in water at a temperature of 15 to 30 ° C is 1.2 to 38, the precipitated sparingly soluble electrolyte is separated from the reaction product constituting the liquid phase by sedimentation and / or filtration and / or centrifugation, or is stabilized in the liquid phase, the reaction product optionally being concentrated and / or supplemented with substances modifying its chemical reaction. 2. A method for producing a composition for inhibiting the function of nitrifying bacteria according to point 1, characterized in that the precipitation chemical reaction is carried out at a temperature of 25 to 60 ° C. 3. A process for the production of a composition for inhibiting the function of nitrifying bacteria according to claim 1, characterized in that the substance providing with a calcium cation present in the system a poorly soluble electrolyte, whose pK _s in water at 15 to 30 ° C is 1.2 to 38 is oxalic acid, (COOH) ₂ and / or sulfuric acid and / or carbon dioxide and / or hexafluorosilicic acid, HgSiFg, and / or hydrofluoric acid, HF.