CZ282157B6 - Process for preparing an agent based on colloidal sulfur obtained from sulfane for the protection of agricultural plants - Google Patents

Abstract

This invention involves the production of a preparation for protecting agricultural cultures and crops. It eliminates energy- and capital demanding milling and insufficient distribution of the particles. The solution is based on the fact that a suspension containing 40 to 99.5% by weight of sulphur is obtained from sulphane containing gas by treating it with an aqueous solution of iron complexes. The created suspension is mixed with 1 to 55% by weight of surfactant with 0.1 to 8% by weight of NH4HCO3 and with 1 to 20% by weight of the aqueous solution of ammonia at a concentration of 1 to 25% by weight. The mixture obtained is milled, passes through a 0.18 x 0.1 mm mesh and then is dried in a drying chamber.

Description

Process for the preparation of a crop protection product based on colloidal sulfur obtained from sulfane

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a process for the preparation of a crop protection product based on sulphide based on colloidal sulfur.

Colloidal sulfur from a plant protection point of view is a fungicide with a surface contact effect. It is applied in the form of spray or dust.

In particular, the following properties are manifested during application:

low toxicity to animals

- in molds and fungi it transforms into sulfane, which acts as a hydrogen acceptor and thus interferes with the vital functions of these organisms when applied to the foliar, creating a weather-resistant adhesive deposit on its surface.

In addition to fungicidal activity, colloidal sulfur has an insecticidal and nutritional effect. It is not toxic to adult insects but acts toxic to eggs and larvae. In this way, it reduces the population of absorbent insects and mites to a low level and allows to keep fungal and fungal diseases within acceptable limits. Colloidal sulfur can also be used to fertilize pastures 25 with high alkalinity and sufficient humus. In general, these properties of colloidal sulfur can be applied to agricultural production in viticulture, orcharding, grain production, oilseed rape, sugar beet, etc. At present, colloidal sulfur-based preparations are produced by first grinding sulfur in the form of an aqueous suspension with the addition of various ingredients , surfactants and the like. The suspension obtained is dried in a spray drier.

A disadvantage of the present process is the energy and investment intensive grinding carried out predominantly in a bead mill, where the particle size distribution of the colloidal sulfur achieved by grinding is not always advantageous, since only about 20% of the sulfur particles have a size in the range of 2-4 µm. or dusts most effective.

Since the grinding segments are also broken during grinding, it is necessary to filter the grinding product before further operations. If the sulfur is ground in two stages, it is necessary after the grinding in the first stage to add to the sulfur an anticoagulant ingredient, usually a mineral oil, but which is unsuitable from an ecological point of view.

The aforementioned drawbacks are eliminated by a process for the preparation of a crop protection product based on colloidal sulfur obtained from the sulfane according to the invention, which is characterized in that the sulfane-containing gas at a concentration of 4-6 g / m ³ is oxidized to sulfur by an aqueous solution prepared from FeSO ₄ . 7 H ₂ O, sodium salts of ethylenediaminotetraacetic acid, sulfuric acid 45 and sodium carbonate.

The colloidal sulfur thus obtained has a substantially more advantageous particle distribution and, in the vast majority of cases, its further grinding can be omitted. Another advantage of the present invention is the utility of the complexing agent remaining in the remainder of the scrubbing solution in the recovered gas desulphurisation slurry 50 or after the removal of water therefrom, to increase the fertility of the treated cultures, In addition, it is possible to add to the composition to be produced which preferably will form complexes and thereby enhance the effect of the composition.

- 1 GB 282157 B6

The advantage according to the invention is also the applicability of sulfur resulting from the desulfurization of gases, which in many cases has not yet been used due to its character.

A certain advantage according to the invention is that the sulfur obtained from the desulfurization of gases can replace the part of the sulfur 5 used from another source, for example, milled sulfur oil.

The process for the preparation of a crop protection product based on colloidal sulfur obtained from sulfane according to the invention is apparent from the following examples:

Example 1

To 830 kg of sulphite liquor is added 250 kg of ground sulfur oiled with 3.9 wt. oil and 508 kg of colloidal sulfur paste (with 57.5 wt.% dry matter and 48.7 wt.% sulfur) produced by scrubbing gas 15 containing sulfane at a concentration of 4-6 g / m ³ by the action of an aqueous solution prepared so that up to 950 1 kg of water was successively added with 40 kg of ethylenediaminotetraacetic acid sodium salt, 25 kg of FeSO4. 7 H ₂ O. 1.65 1 H ₂ SO ₄ 95% wt. and 25.5 kg Na ₂ COa. 50 L of 23.5 wt. ammonia water and 27 kg NH4HCO3 and milled for 120 minutes in a pearl mill. The ground paste is passed through a sieve and dried in a spray drier at 122-130 ° C. The resulting 20 product contains 48.5 wt. sulfur with a predominant particle size of 1 to 8 microns.

Example 2

To 800 kg of sulphite liquor treated with 50 kg of 25% wt. ammonia water a26kgNH ₄ HCO _? 1060 kg of colloidal sulfur paste (dry matter 55 wt% and sulfur content 47.5 wt%) was added. washing the resulting gas containing hydrogen sulfide at a concentration of 4-6 g / m ^J with an aqueous solution prepared so that the 930 1 of water was gradually added 37 kg of sodium ethylenediaminetetraacetic acid, 23.5 kg FeSO. 7 H ₂ O, 1.45 1 H ₂ SO 4 95% wt.

and 24.5 kg of Na ₂ CO-. The resulting paste was passed through a 0.18 x 0.10 mm sieve and dried at 122-130 ° C with hot air in a spray drier. The resulting product contains 48.8% wt. sulfur, with nearly half of the particles being 2-6 microns in size.

Example 3

The homogenized paste according to Example 2 is ground before being dried in a pearl mill, sieved and dried in a hot-air spray dryer at 122-130 ° C. The resulting product contains 48.2 wt% sulfur, predominantly having a particle size of 1 to 4 microns.

Example 4

K. 1050 kg of the sulfur suspension produced by the procedure of Example 2 were added 670 kg of sulphite liquor 45 neutralized with 50 kg of 25 wt. aqueous ammonia solution and 20 kg NaHCO ₂ and 142 kg sodium tetraborate. After homogenization, the resulting paste was spray dried in a jet of hot air at a temperature of 125-130 ° C. The resulting product contains 49.8 wt. sulfur and 1.5 wt. boron.

. 50

Example 5

The solution specified in Example 2 was scrubbed with biogas falling off the decomposition of pig slurry. The resulting sulfur suspension was treated analogously to Example 2.

Example 6

Sulfur slurry obtained in the purification of urban sewage gas using the solution specified in Example 2 was used for the composition of the invention.

Claims (5)

PATENT CLAIMS A process for the preparation of a crop protection product based on sulphide obtained from sulphide, characterized in that the sulphane-containing gas is treated with an aqueous solution of iron-ethylenediaminetetraacetic acid complexes in a weight ratio of 1: 5 to 7, Dry matter 28 to 65% by weight containing 40 to 99.5% by weight sulfur is mixed with 1 to 55% by weight surfactant, 0.1 to 8% by weight ammonium carbonate, 1 to 20% by weight aqueous ammonia solution having a concentration of 1 % to 25% by weight and the resulting mixture is dried. Method for the preparation of the composition according to claim 1, characterized in that before drying the prepared mixture is subjected to grinding, preferably in a bead mill. 3. A method according to claim 1 or 2, characterized in that, before drying, the mixture is passed through a sieve having a mesh size of 0.18 * 0.1 millimeter. 4. A process according to claim 1 wherein the surfactant is a sulphite liquor. 5. Process for producing the preparation according to claim 1, characterized in that the mixture obtained is dried in a stream of hot gas at a temperature of 110-140 ⁰ C.