DK145139B - PROCEDURE FOR THE PREPARATION OF A GRANULATED OR POWDER-DEFINATED DERIVATIVE AND CARRIER FOR PESTICIDES LEAF AND EARTH FERTILIZERS BASED ON MINERALS OF THE PLASTER - Google Patents

Description

ί dy PRESENTATION SCRIPTURE (s) 1451 39 B

(roll i n i V PR /

(19) DENMARK

PATENT AND TRADEMARKET DIRECTORATE

(21) Application No. 4513/74 (51) IfttCI. * C O A B 11/02 (22) Filing date 23 Aug. 1974 A01 N 25/08 (24) Race day 25 · Aug. 1974 (41) Aim. available Feb 25 1975 (44) Presented 15- S ep. 1982 (86) International application # - (86) International filing day - (85) Continuation day - (62) Master application no -

(30) Priority Aug 24 1973, 85592/73, IT

(71) Applicant BRUNO FABBIAN, Asigllano Veneto (Vicenza), IT.

(72) Inventor Same, (74) International Patent Bureau Agent.

(54) Process for the preparation of a granular or powdery diluent and / or carrier for pesticides, foliar and soil fertilizers, on the basis of minerals of the plaster series.

The present invention relates to a process for the preparation of a granular or powdery diluent and / or carrier for pesticides, leaf and soil fertilizers, based on minerals of the plaster row.

It is known in science, in the art and in practice that for the purpose of obtaining a suitable distribution and use of products suitable for the protection of crops and for enhancing their development or suitable for control. In the absence of nutritional deficiencies, it is necessary to provide in advance a formulation of these products in terms of concentrations and forms which are more appropriate and stable, so that the result is a valuable biological efficiency and an easy and practical application.

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The most commonly used forms of the above mentioned products are as follows:

Wettable powders

Dust riddles - powders

Emulsifiable concentrates

Emulsions that can be diluted with water

Solutions that can be mixed with water

Granular formulations

pellets

For each of said forms, the resulting composition generally comprises:

The active ingredient (which may be a natural or synthetic product of medium or high purity).

Tensioactive, adhesive, staining, synergistic, stabilizing components as well as components for regulating evaporation and release.

Inert constituents (aromatic, aliphatic, polar and aqueous solvents, solid mineral or synthetic or vegetable materials).

Among these inert precursors (used to bring the concentration of the active ingredient to the desired or appropriate values or within the limits permitted by law), the following are widely used:.

For pesticides in the form of wettable powders or dusting agents:

Talc, kaolinites, diatomites, silica or silica, alkaline earth metal carbonates, alkaline earth metal hydroxides, montmorillonites, attapulgites, vegetable products, tripolites, dolomites, clay products, phosphates, pyrophyllites, synthetic products and other products.

For granular or granular products:

Vegetable products, calcites, dolomites, vermiculites, sulfates, mica, pyrophyllites, montmorillonites, kaolinites, attapulgites, clays, phosphates, nitrates, sulfates, silicates, pumice, synthetic products and other products.

The term "inert ingredient" is generally understood to mean an ingredient which does not react with the active ingredient of the preparation or its additives.

Of course, for each formulation, the mineralogical, structural, chemical and physicochemical properties of these inert components must be assessed in advance.

Among these properties, some are inappropriate in that they induce and catalyze the more or less rapid decomposition of the active ingredient, for example: A. The moisture or water content (constitutional or residual water resulting from mixing or processing).

B. Acid surface centers or catalytic surface activity.

C. Cation exchange ability, depending on the mineralogical group, the crystal structure and the mode of treatment.

The disadvantages listed under B. and C. above are, although they have been the subject of lengthy and in-depth studies, not yet remedied, with the exception of the finding of the effect and the possibility of attenuating or eliminating this effect. of special substances to be introduced at the time of formulation, such as: 1. glycols, 2. urea, 3. hexamethylenetetramine, 4. other substances.

Such introduction at the time of formulation is not always possible for formulation technical and financial reasons.

Furthermore, it should be noted that the catalytic surface activity and ion exchange ability, in addition to being the main cause and determining factor for the degradation of the active ingredient, can in some cases immediately and definitively change the chemical structure of the active ingredient to such an extent that its biological effect is completely removed. .

It is an object of the invention to remedy this disadvantage in a simple and effective manner.

Studies and practical experiments performed with the minerals listed below have shown that it is possible at some process steps to obtain inert products that are completely free of acidic centers or have only weak traces thereof and whose ion exchange capacity is impaired to such an extent that it can be considered to be practically negligible in terms of the stability of the active ingredient, so it is not necessary, at the time of formulation, to add the deactivating agents already mentioned:

Selenites, sericulites, alabaster, anhydrites, aragonites, apatites, chalk stones, limestones, granular types of marble, limestone building blocks, dolomitic limestones, marble or clay limestones, white clays, limestone types, stalactites, stalactites, stalagites, , nonionic tensioactive substances and / or anionic tensioactive substances or mixtures of nonionic and / or cationic substances, or glycols, urea, hexamethylenetetramine or other substances.

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Among the aforementioned minerals, minerals of the plaster series have been found to be especially valuable and useful. They have the following characteristics:

Mineralogical group.

6th grade minerals - drywall.

Hydrated sulfates free from foreign anions, in the following forms: crystalline selenite fibrous sericulite compact, spotty, granular alabaster chemical name calcium sulfate dihydrate chemical formula CaSO. , 2 Ho0 class prismatic crystallization system monoclinic lattice ionic hardness according to Moh's scale 2 density 2.30

Anhydrous calcium sulfate in the following form: crystalline anhydrite chemical name anhydrous calcium sulfate chemical formula CaSO.

4 class bipyramidal crystallization system rhombic lattice ionic hardness according to Moh's scale 3-3.5 density 3.0

According to the colloid theory, the curing phenomenon associated with such materials appears to be due to the effect of water on the original burnt product, forming gels from the colloidal solution or dispersion of dihydrated gypsum. From these gels crystals of dihydrated calcium sulfate (in the form of long needles) are formed, thickly interwoven, to produce a dense consistency and therefore cure, causing greater cohesion between the crystals among themselves.

According to the invention, on the basis of such minerals of the plaster series, finished diluents and / or carriers are intended for later impregnation with pesticides or fertilizers, which carriers are generally useful, being free or almost free of acidic surface centers and cation exchange performance.

Thus, they can be used as carriers for even very sensitive active substances.

The process of the invention for the preparation of these novel diluents and / or carriers is characterized by burning a mineral consisting essentially of calcium sulfate to form roasted gypsum, ot gypsum, β-gypsum, γ-gypsum or hydraulic gypsum , deactivates and cures the burnt product by adding water to disperse or dissolve the product, adding to the water the usual curing and granulating auxiliaries selected from alkali and alkaline earth metal chlorides, potassium aluminum double sulfates, nonionic and / or anionic and / or cationic surfactants and / or mixtures thereof, natural and / or synthetic resins, vegetable polymers, polymerized vegetable adhesives, polymerized vegetable oils, polyvinyl chlorides or acetates, in natural or emulsified, curing retardants, alkaline sulfate or tannin derivatives or lignin alkaline earth metals or the like amphoteric metals, and plasticizing synthetic products for plastics or polymerizable materials or for rubber blends, and, if desired or necessary, one or more substances to further reduce the acidic surface centers of the burned material, surface catalytic activity and cation exchange performance selected from electron, oxygen and nitrogen donors by which the product is granulated, dried and optionally pulverized to obtain a product substantially free of acidic surface centers, surface catalytic activity and cation exchange ability.

The procedure will be described below in more detail.

Burning.

For the transfer of CaSO2, 2 Η,, Ο in more interesting products, the firing temperature is gradually and progressively increased as shown in the following scheme.

CaSO4, 2 H2O 120-130 ° C CaSO4, 1/2 H2O burnt plaster

CaSO4, 1/2 H2 O over 130 ° C a-CaSO4 and gypsum a-CaSO4 over 300 ° C P-CaSO4 β-gypsum P-CaSO4 over 600 ° C JJ-CaSO4 tf-gypsum (a variant of anhydrite) 2f- CaS04 800-1000 ° C hydraulic plaster

Deactivation and hardening.

The burnt products are dissolved or dispersed in water, and the usual auxiliaries are cured for curing, as needed, curing retarding or curing accelerants, and for granulation such as e.g. binders or substances which support the formation of particularly strong or dense granules or granules with particularly good absorbency.

Examples of such auxiliaries are:

Alkali and alkaline earth metal chlorides, potassium aluminum double sulfate (curing retardant or accelerating according to the amount used), nonionic surfactants (moderate curing retardant, eliciting good micro-porosity in granules), anionic and cationic surfactant surfactant (anionic and cationic surfactants) and / or synthetic resins, polymers of vegetable origin, polymerized vegetable adhesives and polymerized vegetable oils (curing retardants, adhesives), polyvinyl chlorides (curing retardants or accelerators, depending on the amount used, binder, medium hardening agent), polyvinyl acetates (moderately curing retardants, giving high hardness and strength granules), tannin derivatives or lignin sulfites or lignin sulfonates of alkali metals, alkaline earth metals or amphoteric metals, and plasticizers (of the polymerizable plastics and caustic) diseases known in the art).

Furthermore, as indicated above, it may be necessary or desirable to add one or more substances to further reduce the acidic surface centers of the burned material and the resulting surface catalytic activity as well as its cation exchange capacity.

For this, electron, oxygen or nitrogen donors are used, e.g. the above-mentioned substances: glycols, urea and hexamethylenetetramine, which it has previously been proposed to introduce into pesticidal agents at the time of formulation, that is, by the combination of active substance and carrier. However, as mentioned above, this is not always possible, in addition, an introduction at this time may not always prevent degradation of the active substance and thus prevent destruction of its biological effect.

In carrying out the process, the pH value and ion exchange capacity of the burnt product is determined by analysis and on the basis of the analysis results the nature and amount of the deactivating additives which may be added to the water are determined.

Conventional industrial processes can be used for burning, curing, granulating, sieving, pelleting, drying minerals (or mixtures thereof with phytoathric substances) and for grinding inert products or chargers, mineral, synthetic or vegetable.

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By the above method:

Granular products with the following chemical-physical properties: physical condition granular with white to white spherical particles with light tones of brown or gray homogeneity, excellent in color; Variable size or granular size or distribution depending on the requirements and intended use of the product pH of a 5% suspension between 6.0 and 9.0 (as required or required) flowability good so that no agglomeration or packing phenomena occur moisture from 0.50% up to a maximum of 3.00% understood as the remainder of the working process (not formation water, crystallization water or constitutional water) extracted as an azeotropic mixture with xylene and / or benzene by means of a Dean & Stark apparatus, modified by Marcusson hygroscopicity from 0.3% to a maximum of 5% hardness or propensity sufficient to keep the granule shape unchanged (possibly with a slight modification of the granulometric distribution) during the processing and operations of bag loading or the like, storage transport, distribution, and during use, using the mechanical apparatus and machinery used on the ground and in the air, maximum oil absorption from 14 up to l 26 g oil per 100 g granular product; used oil: paraffin oil having a viscosity of 2.8-3.0 ° E measured at 100 ° F (37.8 ° C) acidic centers or catalytically not present, or little traces (qualitative surface activity test with p dimethylaminoazobenzene as indicator). . From 0 to 3 milliequivalents per minute. 100 g granules (quantitative test with benzylamine and n-butylamine) volume weight up to approx. l, o g / ml $ packed from approx.

. 0.7 to 1.2 g / ml particle size from 3.00 mm to 10.00 mm "1.50" "3.00" "0.75" "2.00" 0.35 "0." 75 "" 0.15 "" 0.25 "as required 9.5139 Dry powders having the following chemical-physical properties: physical condition powders color from white to white with light tones of brown or gray homogeneity, excellent pH of a 57. Suspension from 6.0 to 9.0 (as needed or required) Volume weight from 0.4 to 0.6 g / ml (approximately) j after deposition or storage: 0.5 to 0.8 g / ml ( approximate flowability moderate moisture from 0.5% to a maximum of 37, hygroscopicity from 0.3% to a maximum of 57.

maximum oil absorption from 14 to 20 g oil per 100 g of product acidic or catalytic centers are not present, or little traces (qualitative surface activity test with p-dimethylaminoazobenzene) cation exchange ability from 0 to 3 milliequivalents per day. 100 g of product (quantitative test with benzylamine and n-butylamine) particle size according to requirements - 90 microns - 74 »- 53" - 44 "or any other sizes as needed

All of the additives mentioned gave the end products, in powder or granular form, especially the latter, a further advantageous property: the slower and more controlled release of the volatile pesticides and thus probably greater persistence of the biological action within acceptable limits without any detectable interference or increase. of the residual amounts of the active ingredients, in addition to what is permitted by the existing laws and sanitary standards.

All end products of the invention can be made in different colors, especially blue, for better identification of the products in the distribution stage.

The invention is further illustrated by the following examples.

145139 lo

Example 1

As starting material, the following gypsum was used which was converted into roasted gypsum (CaSO 2, 1/2 H 2 O) by heating to 120-130 ° C. The gypsum pH and ion exchange ability before and after firing were as indicated.

Plaster type Occurrence pH (5% suspension) Ion exchange capacity unburned Lombardia B 7.2 11-13 meq / 100 g roasted 7.0 10-11 meq / 100 g

When it. If the pH value of roasted gypsum was satisfactory, it was sufficient for the water used to cure and granulate to add an additive to deactivate acidic surface centers and decrease the cation exchange capacity.

The following were used:

CaSQ ^, 1/2 Hj> 0 1000 g H2 O 300 g

Diethylene glycol 1.5 g

In addition, the usual hardening and granulating auxiliaries, for example 0.5 g of polyvinyl acetate emulsion ....... are added to the water as a hardening retardant and hardness enhancer.

The obtained granules had the following properties: pH (5? Suspension) 7 acidic surface centers very weak pink color ion exchange capacity 4.8 meq / 100 g

Example 2.

As Example 1, but with 3 g of urea as deactivator of acidic surface centers and ion exchange solvents instead of 1.5 g of diethylene glycol,

Example 3

As Example 1 but with 2 g of hexamethylenetetramine instead of 1.5 g of diethylene glycol; ...... · - -