CS243558B1 - A method for preparing concentrated, finely dispersed metal salts of alkyldithiocarbamic acids 1X - Google Patents

Abstract

The invention relates to a method for preparing concentrated, finely dispersed metal salts of alkyldithiocarbamic acids by reacting a water-soluble salt of alkyldithiocarbamic acid with at least one water-soluble salt of manganese and/or zinc and/or copper. After removing the salt formed in the reaction mixture as a by-product of the precipitation reaction, a substance with a boiling point of its mixture with water lower than the boiling point of water is added to the main product of the precipitation reaction, while this substance is limitedly miscible with water and its specific gravity at the same temperature is lower or higher than its specific gravity of water. After optionally adding a salt of zinc and/or manganese and/or copper, this mixture is brought to a boil at atmospheric or lower pressure, water is separated from the mixture of vapors after their condensation, and the substance or mixture of substances characterized by the above properties is returned back to the environment in which the mixture is boiled and distilled. The invention can be used in industrial practice.

Description

The invention relates to a method for preparing concentrated, finely dispersed metal salts of alkyldithiocarbamic acids.

Several organic sulfur compounds containing the group:

\

N—C—S—

S are among the traditional agrochemicals produced and used today, such as many important fungicides (NABAM, AMBAM, MANEB, ZINEB, MANKOZEB, FERBAM, TERBAM, MARBAM, ZIRAM, PROPINEB, or MEZINEB, METIRAM), fumigants (VAPAM), nematicides (MYLON), dry seed dressings (THIRAM, or THIURAM).

Some of the compounds of this type have also found use as nitrification inhibitors, industrial fungicides, rubber chemicals, human and veterinary therapeutics, inhibitors of microbial corrosion of metals, chemical-analytical reagents, and the like.

Their main representatives are dithiocarbamates derived from the hypothetical dithiocarbamic acid:

H2N—C—SH

With

The replacement of the hydrogens of the amino group with alkyls and the hydrogens of the dithiocarboxylic group with metal usually significantly affects the agrochemical effectiveness of these substances.

The most important fungicides of the dithiocarbamate type include MANEB (1,2-ethane-manganese bisdithiocarbamate) (I)

S S

II II (—Mn—S—C—NH—CH2—CH2—NH—C—S—) _n (I)

ZINEB (zinc 1,2-ethanebisdithiocarbamate) (II)

S S

II II (—Zn—S—C—NH—CH2— CH2—NH—C—S— ) _n (Π)

MANCOZEB (coordination compound of zinc cation with manganese(II) 1,2-ethanebisdithiocarbamate) (III)

S S

II II (—Mn—S—C—NH—CH2—CH2—NH—C—S—) _n (Zn) _m

With considerable simplification, it can be stated that their preparation takes place in two stages. In the first, the reaction of 1,2-ethanediamine (ethylenediamine), carbon disulfide and the appropriate alkali (NH3, NaOH, KOH, Ca2OH2) in an aqueous medium produces the appropriate water-soluble salt of 1,2-ethane-bis-dithiocarbamic acid, which is precipitated in the next stage with manganese and/or zinc ions, most often with an aqueous solution of sulfate or chloride.

NH2— CH2— CH2— NH2 + 2 CS2 + 2 NH4OH—

With

II

CH2—NH—C—S—NH4 + 2 H2O CH2—NH—C—S—NH4

With

With

II S

CH2—NH—C—S—NHz || n | -(- nZnCl2— (—Zn—S—C-NH-CH2—CH2-NH—C—S- j _n + 2 n NHíCI

CH2—NH—C—S—NHi

The disodium salt of 1,2-ethane-bis-dithiocarbamic acid (NABAM), the first of the synthetic bisdithiocarbamates, was first prepared in the laboratories of Rohm and Haas Co. in 1935 by HESTER. A few years later, HESTER and HILL (U.S. Pat. No. 2,317,765) and also DIMOND, HEUBERGER and HORSFALL (Phytopathology, 1943, 33, 1095) described the fungicidal properties of these compounds. These two findings were of decisive importance for the development of 1,2-ethane-bis-dithiocarbamates as the most widely used organic fungicides in agricultural practice.

The history of their development is presented in their review by MOREHART and GROSSAN (Agricultural Experiment Station, University of Delaware, Bulletin No. 357, 1965).

Unlike NABAM, which is readily soluble in water and can be crystallized as a defined compound (b.p. 80 to 81 °C), the structure of MANEB, ZINEB and MANCOZEB is not yet fully understood. According to the latest studies, these have a polymeric nature, which also explains their very poor solubility in water.

VONK (Decomposition of bisdithiocarbamates and their metabolism by plants and microorganisms. Dissertation, Utrecht, April 1975] assumes, for example, the following polymer-coordination structure for ZINEB:

C-NW-CHrCH-ø7H-C

- S .Z (S $ /f / 4 í

Zn

With

Zn s s cThe preparation of metal salts of 1,2-ethane-bis-dithiocarbamic acid, especially MANEB, ZINEB and MANCOZEB, is covered by several professional publications and patents. The following may be cited, for example: USA Pat. No. 2,504,404, 2,855,418, 2,974,156, 3,379,610, 3,497,598, 3,856,836, 4,217,293, French Pat. No. 1,158,574 and 1,234,005, British Pat. No. 1,107,568, German Pat. No. 2,710,469 and Belgian Pat. No. 890,669.

The batch preparation methods described therein differ in preparation conditions, such as: the type of water-soluble salt of 1,2-ethanebisdithiocarbamic acid used as well as the type of water-soluble salt of manganese and/or zinc used for precipitation, the order of addition of the reacting components, their concentration, the pH value of the reaction mixture, the temperature, the type of stabilizing and other additives used, the method of separation of the reaction mixture, the method of drying the product, and the like.

As reported by NEWSOME (Ethylenebisdithiocarbamates and Their Degradation Products-Analytical Methods for Pesticides and Plant Growth Regulators, Vol. XI, Academie Press, lne. 1980) derivatives of 1,2-ethane-bis-dithiocarbamic acid are relatively less stable.

Among the decomposition products identified were:

ethylenethiourea (C3H6N2S), ethyleneurea (C3H6N2O),

2-imidazoline (C3H6N2], ethylenethiurammonosulfide (C4H4N2S3), ethylenebisisothiocyanate (C4H4N2S j and some others. (LUDWIG, R. A. — THORN, G. D. — UNWIN, C. H.: Can. J. Bot. 1955, 33, pp. 42 to 59; CZEGLEDI-JANKO, G.: J. Chromatog. 1967, 31, pp. 89 to 95.)

As shown in their publication by BONTOYAN and LOOKER (J. Agric. Food Chem. 1973, 21, pp. 338-341), MANEB appears to be less stable than zinc-containing products.

ENGST and SCHNAAK (Z. Lebensm.-Unters. Forsch. 1967, 134, pp. 216 to 221) and also HYLIN (Bull. Environ. Contam. Toxicol 1973, 10, pp. 227 to 233) found that the decomposition of MANEB in the aquatic environment produces almost all of the above-mentioned compounds.

Several of the secondary undesirable products can be formed in the reaction mixture already during the preparation of metal salts of 1,2-ethane-bis-dithiocarbamic acid, especially when favorable conditions are created for the course of the secondary reactions. THORN and LUDWIG (J. Appl. Chem. 1962, 12, pp. 90 to 92], for example, report that the effect of atmospheric oxygen on aqueous solutions of NABAM in the presence of Mn ²⁺ salts (catalytic effect) produces ethylenethiuram monosulfide and ethylenethiourea.

The same substances were identified in aqueous suspensions of MANEB by ENGST and SCHNAAK (Z. Lebensm.-Unters. Forsch. 1970, 143, p. 243558 to 99). These authors also determined the presence of ethylenethiuram disulfide in the system.

The presence of ethylthiourea in the reaction mixtures for the preparation of ZINEB, MANEB and MANCOZEB was also confirmed by BONTOYAN and co-workers (J. Ass. Offic. Anal. Chem., 1972, 55, p. 923).

A number of compounds have been patented in recent years with the aim of inhibiting the formation of undesirable by-products in the dithiocarbamate production process and stabilizing the reaction products. These include: sodium or calcium sulfite (US Pat. No. 2,665,285), hexamethylenetetramine-urotropine (FRG Pat. No. 1,113,607; US Pat. No. 2,974,156; French Pat. No. 1,234,005), the addition of various metal salts (Dutch Pat. No. 288,629); 1,3,5-tris (cyanomethyl) hexahydrotriazine and/or dinitroso-pentamethylenetetramine (British Pat. No. 1,119,029], o-, m-, or p-phenylenediamine (French Pat. No. 1,374,622), paraformaldehyde (French Pat. No. 1,344,342: U.S. Pat. No. 4,217,293), formaldehyde (U.S. Pat. Nos. 3,856,836 and 4,217,293] and also some others.

According to some foreign studies, in an attempt to deepen the polymeric character of the structure of metal salts of 1,2-ethane-bis-dithiocarbamic acid, especially MANEB, and thus increase the stability of these compounds, it is recommended to use concentrated solutions of all reaction components in their preparation.

It is known from practical knowledge, as well as from data in professional and patent literature, that in the usual method of preparing metal salts of 1,2-ethane-bis-dithiocarbamic acid, the product of the precipitation reaction is obtained in the form of a relatively very coarse-grained, rapidly sedimenting precipitate, which needs to be further treated by grinding in subsequent stages of the technological process.

Dry, but also wet, grinding of products of this type is a source of significant increase in the investment and energy requirements of the technological process and also creates favorable conditions for oxidative, hydrolytic and thermal degradation of the active substance.

Although the degree of particle dispersion of the precipitation reaction product can be significantly influenced by the conditions under which the preparation of metal salts of 1,2-ethane-bis-dithiocarbamic acid (No. AO No. 237 874) takes place, the achieved fineness of the product usually does not directly meet the requirements placed on the final preparations in this regard.

At least the same problems in terms of technological operating practice are also associated with the dewatering of the precipitation reaction products after removal of the salt formed in the reaction mixture as a by-product of the precipitation reaction (usually ammonium, sodium, potassium or calcium salt of the relevant anion - mostly sulfate, chloride or acetate).

Low thermal stability (pyrolysis occurs above 130 to 135 °C, while the products, especially in the presence of water and free metal cations, decompose even at temperatures only slightly higher than room temperature) and also the fact that most metal salts of alkyldithiocarbamic acids form hydrates binding different amounts of water in their crystal lattices usually impose special requirements on the drying of products of this type.

However, achieving the highest possible degree of dehydration of the precipitation reaction products is of considerable importance from the point of view of ensuring the necessary stability of the active substance in the final preparations during their storage. For the above reasons, drying of these reaction products is often carried out in several stages, usually working in a protective layer of inert gases and at significantly reduced pressures.

In this context, for example, a combination of a spray dryer with subsequent dehydration of the pre-dried material by gentle heating with intensive mixing under vacuum has been used in operational practice. It can also be seen from the above that the dehydration of metal salts of alkyldithiocarbamic acids is a very demanding operation in terms of investment, operation and energy, which places extremely high demands on the equipment of the operation with several special and hardly available devices and requires a high level of adherence to technological discipline.

It has now been found that the vast majority of the above-mentioned disadvantages can be eliminated by the method of preparing concentrated and finely dispersed metal salts of alkyldithiocarbamic acids by reacting a water-soluble salt of alkyldithiocarbamic acid with at least one water-soluble salt of manganese and/or zinc and/or copper according to the invention.

The essence of the invention lies in the fact that, after removing the salt formed in the reaction mixture as a by-product of the precipitation reaction, at least one of the group of substances whose boiling point of their mixture with water is lower than the boiling point of pure water under the same pressure conditions is added to the main product of the precipitation reaction in a wet state, whereby such a substance or mixture of substances is miscible with water to a limited extent.

For this substance or mixture of such substances, it is further true that its specific gravity at the same temperature is lower or higher than the specific gravity of water.

Further, to the main reaction product of the precipitation reaction, optionally, some of the salts of zinc and/or copper and/or manganese are added, and optionally, some of the substances stabilizing the reaction product are also added. The mixture thus obtained is subjected to boiling at atmospheric pressure or a pressure lower than atmospheric pressure, with water being separated from the mixture of vapors after their condensation, and the substance or mixture of substances characterized by the above properties is returned back to the environment in which boiling and distillation occur.

In the interest of achieving significant simplification and thus efficiency of the technology for the preparation of concentrated, finely dispersed metal salts of alkyldithiocarbamic acids, water distillation can be carried out even in the presence of finalizing additives - substances modifying the properties of the active substance.

Among the substances which have proven to be suitable for the preparation of concentrated, finely dispersed metal salts of alkyldithiocarbamic acids by the method according to the invention even at atmospheric pressure, the following may be mentioned, for example: n-alkali (n-pentane, n-hexane), petroleum ether, cyclohexane, gasoline, trichloromethane-chloroform, carbon disulfide and the like. At reduced pressure, for example: carbon tetrachloride - carbon tetrachloride, benzene, toluene, xylene and some other additives may be used.

The method for preparing concentrated metal salts of alkyldithiocarbamic acids according to the invention can be theoretically justified as follows:

When two mutually insoluble and chemically inert liquids (substance A and substance B) are heated together, each of them evaporates as if the other substance were not in the system. Their partial vapor pressures are therefore equal to the vapor pressures of the pure components p ^s A and p° _B . Assuming that Dalton's law applies to the gaseous mixture, we can write the total pressure over the mixture of both liquids P as:

P = ρ° _Λ + p° _B .

Since the saturated vapor pressure of the pure components p° _A and ρ ^σ Β does not depend on their amounts, the total pressure above a mixture of liquids obviously does not depend on their mutual ratio in the mixture.

As is known, a liquid boils when the pressure of its saturated vapor equals the ambient — external pressure. Since the total pressure P is always greater than the value of the partial pressures of the individual pure components Ρ°λ and P°b, the boiling point of such a mixture is always lower than the boiling points of both pure components of the mixture. The boiling point of such a mixture remains constant until one of the components evaporates completely. Then the temperature changes abruptly to the boiling point of the other component.

The following examples illustrate, but are not intended to limit, the method of preparing concentrated and finely dispersed metal salts of alkyldithiocarbamic acids according to the invention.

Example 1

An aqueous solution of ammonium ethylenebisdithiocarbamate was prepared by a modified FLENNR procedure (U.S. Pat. No. 2,609,389) under the supervision of ZAVIZIN (Chim. Prom. 3, 174-175, 1972).

Into a sulfonation flask equipped with a reflux condenser, a stirrer, a glass and saturated calomel electrode, dropping funnels and a thermometer, placed in a temperature-controlled water bath, were weighed 511.54 g of distilled water and 310.31 g of chemically purified and distilled carbon disulfide (PITRA, J. — VESELÝ, Z. KAVKA, F.: Laboratory treatment of chemicals and auxiliary substances. SNTL — Prague 1969, p. 80} layered with 26.76 g of distilled water.

While stirring and circulating water through the reflux condenser, 115.57 g of predistilled 1,2-ethanediamine (ethylenediamine) was added to the flask over a period of 25 minutes through a dropping funnel below the level of the reservoir. During the addition of 1,2-ethanediamine, the temperature of the reaction mixture increased from 20.5 °C to 38.5 ^° C, while the pH of the reaction mixture increased from the original 5.7 to 10.1 within the first five minutes and then gradually decreased to a value of 7.70.

After the entire weight of 1,2-ethanediamine was added, the 25.16% ammonia water was added evenly through the dropping funnel. Over the course of 15 minutes, 263.1 g of this ammonia water was added, while the reaction mixture was heated to 42 °C and the pH of the reaction mixture reached a value of 8.6.

After the addition of ammonia water was completed, the reaction mixture was heated to a temperature of approximately 40 °C for two hours with constant stirring (the pH value of the reaction mixture after the end of the heating was 8.9). Then, the reflux condenser and both dropping funnels were removed from the sulfonation flask and the reaction mixture was quickly heated to a temperature of 57 °C with stirring, thereby removing the remains of unreacted CS2.

After cooling the reaction product — rye-colored clear solution, the content of the active substance was determined by chemical analysis. The result of the analysis showed that approximately 1.2 kg of a 36.4% aqueous solution of ammonium 1,2-ethane-bisdithiocarbamate was prepared by the above procedure. The prepared aqueous solution of ammonium 1,2-ethane-bisdithiocarbamate (EBDTK-NH4) was used in the preparation of concentrated metal salts by the traditional method, as well as by the method according to the invention. Example 2 and 3

In the interest of preparing comparative — control samples of concentrated metal — manganese salts of 1,2-ethane-bisdithiocarbamic acid (MANEB), two different classical methods were used in the preparation of samples No. 2 and 3. In the case of the preparation of sample No. 2, the cake of the active substance washed with distilled water after precipitation was dried in an air atmosphere at atmospheric pressure at a temperature of 50 to 60 °C. In the preparation of sample No. 3, the filter cake, after washing with distilled water, was dried in a laboratory vacuum drying cabinet type at a temperature of 40 to 45 °C.

The filter cake was prepared as follows:

Into a beaker containing about 63.1 g of a 36.4 percent aqueous solution of ammonium 1,2-ethane-bis-dithiocarbamate (EBDTK-NH3) was poured, while stirring with a glass rod, about 36.9 g of an aqueous solution of MnSO3 containing 13.86 ⁰ Mn. The reaction mixture was stirred for 5 minutes and then allowed to settle freely for 30 minutes. Then the clarified layer above the precipitate was decanted and the precipitate was poured into about 200 ^cm3 of distilled water. After thorough mixing, the precipitate was allowed to settle freely again for 30 minutes.

After the clarified aqueous layer was decanted again, the decantation of the precipitate with distilled water was repeated once more in a similar manner. After the clarified aqueous layer was decanted after the second decantation, further portions of the aqueous phase were removed from the precipitate by filtration through folded filter paper, with approximately 50 cm ³ of distilled water being used to quantitatively transfer the precipitate to the filter and wash it.

The wet filter cake was then (in the case of examples 2 and 3, respectively) transferred from the filter paper to a watch glass and further dried in air at atmospheric pressure or under vacuum (laboratory oil rotary vacuum pump) to a constant weight of the dried samples.

When drying in a laboratory drying cabinet at atmospheric pressure (preparation of sample no. 2), the average temperature was measured to be 52.7 °C, with the extreme values determined by the measurement being: min. 48 °C and max. 60 °C. Drying was completed after 1,650 minutes, when the sample showed a constant weight under the specified drying conditions. A sample of untreated MANEB was prepared in this way, which contained:

40.63 wt. % total sulfur

10.33 wt. % total nitrogen and

17.92 wt. % manganese.

The above-mentioned results of the chemical analysis showed that, with respect to the sulfur content, the obtained product contained 84.05% of the active substance, while the content of the active substance based on Mn was 86.53%.

When preparing sample No. 2 by drying the washed filter cake in a laboratory vacuum drying chamber, drying was carried out under the vacuum of a laboratory rotary oil pump at a temperature of 40 °C to 45 degrees C. Drying under these conditions was completed after 1,335 minutes, when the weight of the dried sample was already constant. The sample of concentrated, untreated MANEB (manganese 1,2-ethane-bis-dithiocarbamate) prepared in this way contained:

38.54 wt. % total sulfur

10.66 wt. % total nitrogen

17.98 wt. % manganese

Based on these chemical analysis results, it can be calculated that the content of the active substance (C6HeN2SiMn) with respect to the sulfur content in the reaction product was 79.73% and with respect to the manganese content was 86.82%.

Both products (samples no. 2 and 3) have a significant coarse-grained character even after being separated with a stick between two papers.

Example 4 to 10

In these laboratory experiments, one of the possible methods according to the invention was used to prepare concentrated manganese(II) 1,2-ethane-bis-dithiocarbamate (MANEB).

In a manner analogous to that given in Examples 2 and 3 and using the same reagents, a wet filter cake washed with distilled water was prepared in connection with these experiments.

Manganese 1,2-ethane-bis-dithiocarbamate.

Part of the wet washed cake was transferred to a boiling flask with a volume of 500 cm ³ , equipped with a central ground glass NZ 29 for placing a distillation attachment with a reflux condenser and with one to two ground glass NZ 14.5 for placing ground glass thermometers (temperature measurement in the vapor and, if applicable, liquid phase).

Next, a batch of wet washed filter cake was soaked with one of the following verified additives according to the invention:

xylene, CsH10 (pure);

petroleum ether (Aether petrolei, 30 to 70 °C, in accordance with TPD 33-045-62);

Benzene, CgH5 (pure);

n-hexane, CHj(CH2)4—CH ₃ (pure, VEB JENAPHARM-LABORCHEMIE APOLDA, DDR); gasoline (pharmaceutical);

toluene, C7H5 (pure, according to PND 36-038-67); cyclohexane, C6H12 (pure).

Then the boiling flask was placed in an electrically heated heating "nest" and a special distillation attachment with a back, water-cooled condenser was placed on the central ground glass NZ 29. The distillation attachment allowed the free passage of vapor from the flask to the back cooler and further ensured continuous distribution of liquid condensate in the separator under the back cooler, as well as a smooth outflow of the lighter organic liquid phase from the upper part of the separator back to the boiling flask. After placing the thermometers in the ground glass tubes (NZ 14.5) and opening the cooling water supply to the back cooler, the boiling flask was heated.

243556

Overview of basic data on laboratory experiments — for examples 4 to 10

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After reaching boiling, the heating was reduced appropriately. The vapor phase consisting of vapors of the organic additive and water condensed in the back condenser and continuously flowed into the separator, in which the specifically heavier water was separated from the organic additive. The separated organic additive flowed through the overflow located in the upper part of the separator back into the boiling flask.

The contents of the boiling flask were maintained at boiling temperature until the volume of water condensate in the separator was still changing. Then the heating was stopped and after the contents of the boiling flask had cooled, the solid phase formed by concentrated 1,2-ethane-bis-dithiocarbamate manganese was separated from the liquid organic additive by filtration through folded filter paper. The residues of the liquid organic additive were removed by evaporation in an evacuated desiccator. An overview of the basic data on the laboratory experiments performed (examples No. 4 to 10) is contained in Table No. 1.

In the case of using xylene (example no. 4) and partly toluene (example no. 9), thermal decomposition of the product occurred due to the excessively high boiling point of the organic additive used, or its mixture with water. The aforementioned additives could be used for the intended purpose at reduced pressure above the boiling point, or in a mixture with another suitable substance within the meaning of the invention. Example 11

In this laboratory experiment, the same apparatus and working procedure were used as in the case of the previous examples No. 4 to 10. Pure pharmaceutical gasoline was used as an additive in the sense of the invention. In contrast to the experiments reported in examples No. 4 to 10, before adding gasoline, approximately 63.1 g of a 36.4% aqueous solution of 1,2-ethane-bis-dithiocarbamate ammonium (EBDTK-NH4) with 36.9 g of an aqueous solution of MnSO4 (13.86% Mn) and a trace amount of crystalline zinc sulfate were added to the washed wet filter cake obtained by precipitation (by the procedure according to examples No. 2 and 3).

The weight amounts of the individual ingredients were as follows:

36.4% aqueous solution of ammonium 1,2-ethane-bis-dithiocarbamate 63.19 g aqueous solution of MnSO4 (13.86% Mn) 36.85 g respectively. for boiling with additive — pure gasoline was weighed:

52.8 g wet water-washed filter cake

2.85 g ZnSO₃. 7 H2O, p. a.

169.5 g of pharmacy gasoline.

The temperature of the liquid and vapor phases at the beginning of the distillation was 64.0 °C and just before its completion it was 66.6 °C. During

After 045 minutes of distillation, 30.2 cm ³ of the aqueous phase was distilled off (the volume of the aqueous phase did not change further). The solid, finely dispersed in gasoline coordination product of the zinc cation with zinc 1,2-ethane-bis-dithiocarbamate (MANCOZEB) was separated from the continuous liquid phase formed by gasoline by filtration through folded filter paper. Filtration yielded 42.9 g of wet MANCOZEB, from which 24.5 g of highly concentrated, very fine MANCOZEB was obtained after evaporation of the gasoline residues in an evacuated desiccator.

Chemical analysis of the obtained product revealed that it contained:

43.85 wt. % total sulfur,

10.21 wt. % total nitrogen,

19.88 wt. % manganese and 1.66 wt. % zinc.

Example 12

In order to obtain an objective idea of the particle size of concentrated metal salts of alkyldithiocarbamic acids obtained by traditional methods, as well as by the process according to the invention, microscopic measurements were made of several samples of manganese 1,2-ethane-bis-dithiocarbamate [MANEB], zinc (ZINEB), as well as samples of the coordination compound of zinc cation with manganese 1,2-ethane-bis-dithiocarbamate (MANCOZEB).

The measurements clearly confirmed that during the dehydration of washed samples of metal salts of alkyldithiocarbamic acids in the presence of additives according to the invention, an effective disintegration of agglomerates occurs down to the form of primary particles. The final result is the formation of significantly finer products, which usually do not require further grinding. The above statements are documented by the following microphotographs of samples of concentrated MANEBs from the experiments described in examples No. 2, 3 and 8 (Fig. 1 to 4).

Example 13

The assembly of the mechanical technological equipment described in this example, illustrating the method of preparing a concentrated and finely dispersed coordination compound of zinc cation with manganese 1,2-ethane-bis-dithiocarbamate (MANCOZEB) according to the invention, is schematically shown in Fig. No. 5.

An aqueous 28.34% solution of the diammonium salt of 1,2-ethane-bis-dithiocarbamic acid (EBDTK-NH4) 101, prepared by the method according to MS. AO no. 237,725, whose specific weight at 20 °C was 1,099.9 kg.

. m~ ³ , pH of the undiluted solution 8.9 and refractive index n20 °C = 1.443,, where for each ^x 3 ? 5 8

To 100 parts by weight of this aqueous solution, 49.12 parts by weight of an aqueous solution of manganese sulfate containing 12.26 percent by weight of Mn 102 was gradually added with efficient stirring.

After the addition of manganese sulfate was completed, 0.1 parts by weight of hexamethylenetetramine — urotropine 103 was added to boiler 1 for every 100 parts by weight of the reaction mixture.

The reaction mixture — an aqueous suspension of bright yellow color was stirred for about 15 minutes. Then the suspension was collected in a stirred tank 2, from which it was transported by a centrifugal pump 3 for separation using a rotary vacuum filter 4, on which the raw filter cake was washed with water 104. The wet filter cake from the rotary vacuum filter 4 was collected in a dissolving kettle 5 equipped with effective stirring, in which the filter cake was dispersed in about 3 times the amount of water 104.

The diluted aqueous suspension of manganese(II) 1,2-ethanebisdithiocarbamate (MANEB) prepared in the above manner was pumped by pump 6 to a rotary vacuum filter 7, where the separation of the solid — discontinuous phase from the filtrate — diluted aqueous solution (NH4SO4), forming the continuous phase of the separated suspension, was achieved.

The filter cake on the filter 7 was washed with an approximately 0.5% aqueous solution of urotropin 105. The wet filter cake from the rotary vacuum filter 7 was collected in containers 8, whereby for each part by weight of Mn ²⁺ in the wet cake, the filter cake was overlaid with 0.55 parts by weight of crystalline ZnSCU. 7 H2O 106 and for every 100 parts by weight of the washed wet filter cake of MANEB, 0.45 parts by weight of urotropin 103 was added.

A batch of wet filter cake, crystalline zinc sulfate, and urotropine was transferred to a Lodige-type dryer 9, to which about 300 parts by weight of gasoline 107 were added from the gasoline tank 10 for every 100 parts by weight of the transferred mixture.

After closing the dryer, with effective mixing, the heating of its contents with circulating hot water began, and after reaching a temperature of approximately 65 ^C C, the contents of the dryer began to boil, while the mixture of gasoline vapors and water condensed in the cooler 11. The condensate consisting of gasoline and water collected in the separator 12, from which the specifically lighter gasoline, forming the upper layer, flowed continuously into the dryer 9 and the water 104 forming the lower layer flowed through the separator 13.

When the condensate behind the cooler 11 no longer contained any water, the reverse flow of gasoline to the dryer was closed and it began to collect in the gasoline tank 10.

In the above-mentioned manner, gasoline was distilled from the material forming the retainer of dryer 9. After removing the last residues of the additive used, the concentrated and very finely dispersed coordination compound of the zinc cation with manganese 1,2-ethane-bis-dithiocarbamate 108, containing 8 parts by weight of bound manganese and 1 part by weight of zinc per 31 parts by weight of 1,2-ethane-bis-dithiocarbamate ion, was discharged from dryer 9 through the outlet opening in the bottom of the dryer, with stirring.

Example 14

The scheme of the mechanical technological equipment presented in this example, illustrating the use of the method for preparing a concentrated and very finely dispersed coordination compound of zinc cation with manganese 1,2-ethane-bis-dithiocarbamate (MANCOZEB), is schematically shown in Figure 6.

In the precipitation kettle 1, crude manganese 1,2-ethane-bis-dithiocarbamate (MANEB) is prepared in a similar manner as in the previous example 13, which is removed from ammonium sulfate, a salt formed in the reaction mixture as a by-product of the precipitation reaction, by repeated decantation at least twice in the washing kettle — decanter 2.

Thickened aqueous suspension of washed

Manganese 1,2-ethane-bis-dithiocarbamate is diluted by adding an additive (e.g. gasoline, cyclohexane, benzene, etc.) 107 and transferred via the appropriate pipeline to the desilylation boiler 3, to which 0.55 parts by weight of crystalline ZnSOi. 7 HaO 106 and 0.075 parts by weight of hexamethylenetetramine — urotropine 103 are further added for each part by weight of manganese in the reaction mixture.

After adding the additive from the reservoir 8, the distillation boiler 3 is closed and, while stirring, its contents are heated with low-pressure steam or hot water so that the suspension boils, while the mixture of additive vapor and water vapor condenses in the cooler 4.

The condensate consisting of a mixture of two mutually miscible liquids is separated in the separator 5, while the additive, characterized by a lower specific gravity than water, forms the upper layer in the separator, and flows through the side overflow back into the column 3, in which the boiling of the reaction mixture takes place.

After distilling off all the water, the backflow of the additive from the separator 5 to the distillation kettle 3 is closed and a part of it is distilled from the reaction mixture into the additive collection tank 8. The thickened suspension of MANCOZEB in the additive is then discharged from the kettle 3 into a Lůdige type dryer 6, to which 0.11 parts by weight of dry dispersant 109, consisting of 50% Slovasol SF and 50% S1O2 and 0.2 parts by weight of powdered thickened sulphite calcined 11a are added for each part by weight of manganese in the reaction mixture.

The residue of the additive is then distilled from the reaction mixture under reduced pressure and heating of the drying chamber with hot circulating water in a duplicator, with effective homogenization of the drying chamber contents. The distilled additive, after condensation in the cooler 7, is collected in the additive reservoir 8.

Example 15

The wet washed filter cake of manganese(II) ethylenebisdithiocarbamate dihydrate, prepared by the procedure described in Examples 2 and 3, was poured into a glass boiling flask (see Examples 4 to 10) with pure pharmaceutical benzine, so that the weight of the benzine was about 7 times the weight of the filter cake.

The flask was placed in an electrically heated "nest", with a special distillation attachment with a back condenser placed on its central ground glass NZ 29 (the function of the attachment is explained in examples 4 to 10) and ground glass heat exchangers were inserted into the side necks of the boiling flask, which ended with ground glass (NZ 14.5), allowing monitoring of the temperatures of the liquid and vapor phases.

After 6 hours of distillation, the amount of water in the separator under the reflux condenser did not change any further, while the composition of the solid portion in the boiling flask corresponded to anhydrous manganese ethylenebisdithiocarbamate (MANEB). The temperature of the liquid and vapor phases during the distillation ranged from 64 to 67 °C.

Then the heating was stopped and after cooling, the gasoline suspension of anhydrous MANEB was separated by filtration.

Next, 10 parts by weight of the anhydrous MANEB obtained by the above method were suspended in an aqueous solution containing 0.5 parts by weight of ZnSO4 in 10 parts by weight of water. The suspension thus prepared was stirred for 1 hour at room temperature (25 to 20 °C). Then the aqueous suspension was layered again with pure pharmaceutical gasoline and the water contained in the reaction system was separated by distillation with gasoline — — in a similar manner as in the case of the previously described dewatering of the washed filter cake of manganese ethylene bisdithiocarbamate dihydrate.

After the distillation of water was completed, the gasoline suspension was separated by filtration, while the gasoline residues were removed from the filter cake by evaporation in an evacuated desiccator. By sieving the product prepared in this way, 9.1 parts by weight of the coordination compound of zinc cation with manganese 1,2-ethane-bis-dithiocarbamate (MANCOZEB) were obtained. The product was thoroughly washed with a mixed solution of methanol and distilled water and dried at 50 °C and a pressure of 5 mm. The product prepared in this way contained 1.9% Zn, 20.3% Mn, 56% CS2, 10.2% N, 17.6% C and 2.3% H.

Claims (1)

243558 17 18 additive residues. The distilled additive after condensation in the condenser 7 is collected in an additive reservoir 8. EXAMPLE 15 A wet washed manganese dihydrogen ethylenebisdithiocarbamidate filter cake, prepared as described in Example 2 and 3, is filled with pure pharmacy benzine in a glass beaker (Examples 4 to 10). The flask was placed in an electrically heated "nest", with a special distillation nozzle placed on it (the function of the nozzle is explained in in Examples 4 to 10) and in the lateral necks of the boiling pot terminated by ground-glass joints (NZ 14.5), the ground-glass heat of the era allows the temperature of the liquid and vapor phase to be monitored. further, the composition of the solid portion in the brewing bank is not changed The manganese (II) anhydrous ethylenebisdithiocarbamidate (MANEB) was used during the distillation, ranging from 64 to 67 ° C. Thereafter, the heating was stopped and after cooling the benzene suspension of anhydrous MANEB was separated by filtration. Furthermore, 10 parts by weight of the anhydrous MA-NEB obtained by said process were suspended in an aqueous solution containing 0.5 wt. parts of ZnSCh in 10 wt. parts of water. The thus prepared suspension was stirred for 1 hour at room temperature (25-20 ° C). Thereafter, the aqueous suspension was overlaid with a pure pharmacybenzine and the water contained in the reaction mixture was separated by distillation with gasoline in a manner similar to that described for dewatering the washed filter cake with ethylene bisdiocarbamidate dihydrate. Upon completion of the distillation of water, the gasoline slurry was separated by filtration, with the remainder of the gasoline removed from the filter cake by evaporation in an evacuated desiccator. zinc cation compound with 1,2-ethane-bis-dithiocarbamate manganese (MANCO-ZEB). The product was thoroughly washed with a mixture of methanol and distilled water and dried at 50 ° C and 5 mm pressure. the product contained 1.9% Zn, 20.3% Mn, 56% CS2, 10.2% N, 17.6% Ca 2.3% H. SUBSTANCE Method for the preparation of concentrated, finely dispersed metal salts of alkyldithio-carbamide acids by water-soluble reaction acid with at least one water-soluble salt of manganese and / or zinc / or a medium characterized in that the major precipitating product is a co-product of the precipitation after removal of the salt formed in the reaction mixture. ] the reaction, at least one of the boiling point of the mixture with water is added to the lower boiling point of the water at the same pressure, such a substance or mixture of substances being limited to water and the specific gravity at the same temperature being lower or higher and, in addition to the specific gravity of water, one of the zinc salts and / or the medium and / or manganese is optionally added to the main reaction product of the precipitation reaction, and optionally one of the reaction product stabilizers is added. At atmospheric pressure or below atmospheric pressure, the boiling point, wherein water is separated from the vapor mixture after condensation, and the substance or mixture characterized by said materials returns to the environment in which it occurs boiling and distillation of the mixture, whereby boiling and distillation also take place in the presence of the finisher product. 4 sheets of drawings