RU2702571C1 - Method of producing a composition for treating cellulose and paper products and a device for carrying out said method - Google Patents

Abstract

FIELD: pulp and paper industry.

SUBSTANCE: obtaining carbonated magnesium alcoholate is carried out by contacting metallic magnesium with alcohol in an atmosphere of inert gas at temperature of +20 °C to boiling temperature of alcohol. Initial content of magnesium in reactionary sweep from 0.01 wt%. up to 5.0 wt%. Obtained suspension is concentrated to the content of magnesium alcoholate in suspension of 2 wt%. up to 40 wt%, but not less than 2 times by distillation of excess alcohol, which is directed for recycling for contact with metal magnesium. Concentrated suspended magnesium alcoholate suspension is dissolved by contacting with carbon dioxide at temperature of +20 °C to boiling temperature of alcohol to obtain a solution of carbonated magnesium alcoholate in alcohol. Target product – a composition for processing cellulose and paper products is obtained by mixing a solution of a carbonated magnesium alcoholate in alcohol with an easily volatile solvent selected from halogen-substituted hydrocarbons. Content of carbonated magnesium alcoholate in the end product is 3.0 wt% up to 25 wt% Method is carried out in a flow type reactor consisting of a container for producing magnesium alcoholate 1, divided into sections for fractionating products and reagents by size of granules, containers for concentration of magnesium alcoholate 2, magnesium alcoholate dilution tanks under action of carbon dioxide 3, connected by products controlled by mass transfer lines and reagents.

EFFECT: disclosed group of inventions increases efficiency and efficiency of the process of producing a carbonated magnesium alkoxide and prevents contamination of the end product with unreacted magnesium particles.

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Description

The invention relates to methods for producing a reagent for processing paper and paper products to slow their aging. Aging of the paper is expressed in a decrease in mechanical strength and a change in color and is caused by chemical changes in the structure of the paper. One of the main processes that occur during paper aging is acid-catalyzed hydrolytic destruction, which occurs in the presence of moisture adsorbed from air. Modern paper of most types contains an increased amount of acid groups in the structure of the polymer chain. Acidic agents can be contained in the paper as a result of processing pulp and paper raw materials with various modifiers. In addition, during storage, paper actively absorbs sulfur dioxide, nitrogen oxides, carbon dioxide, and ozone from polluted air. Oxidative processes lead to the shortening of polymer chains, and also increase the acidity of the paper. Thus, aging paper is an autocatalytic process and can accelerate over time. The main methods to combat paper aging are associated with the search for ways to reduce the acidity of paper.

To reduce the acidity of the paper, various reagents with a high pH are used that can neutralize the acid groups in the paper, as well as form a reserve of a neutralizing agent (alkaline reserve) to prevent further hydrolytic destruction. The first technologies used involved the manual processing of paper products and the use of aqueous solutions of bases and alkaline earth metal salts. Such processes were laborious and inefficient. More modern technologies involve the use of alkaline reagents, dissolved or dispersed in rapidly evaporating non-aqueous media (volatile organic solvents). Such reagents provide quick drying of the object after processing.

Book processing methods based on the use of magnesium alcoholates in a mixture of alcohols and fluorinated hydrocarbons are widely used. This approach is scalable, as a result of which it is possible to process several hundred books in one cycle. Halogen alkanes evaporate quickly, minimizing the effects of solvent on paper and ink. Magnesium alcoholate reagent provides a high alkaline reserve. The alcoholate concentration in alcohol is about 5-20%. To process books, a solution of magnesium alcoholate in alcohol is dispersed in chlorofluorocarbons, such as trichlorofluoromethane or dichlorodifluoromethane, to a final concentration of magnesium alcoholate of 1-3%.

Alkoxides of metals of groups II and III are obtained by the interaction of metals with alcohols at a temperature of 100-200 ° C (US Pat. No. US 3920713 from 1975, US 6676856 from 2004, US 3657361 from 1972). The use of magnesium alcoholates in the corresponding alcohols is characterized by some features. Most magnesium alcoholates are insoluble in the corresponding alcohols, and are also hydrolyzed even in the presence of traces of moisture, which complicates the long-term storage of the reagent and complicates the processing of books, especially in the case of spraying or brushing (US Pat. No. US 3,676182, 1972).

More stable are reagents based on carbonated magnesium alcoholates. Alkyl carbonates alkoxy magnesium are soluble in the corresponding alcohols from which they were obtained. The synthesis is carried out by dissolving the previously synthesized magnesium alcoholate in alcohol by saturating it with carbon dioxide, resulting in a homogeneous solution.

A known method of obtaining a composition for the treatment of pulp and paper products, which consists in obtaining carbonated magnesium alcoholate by reacting magnesium metal with methanol or ethanol, subsequently dissolving the precipitate of magnesium alcoholate by contacting the reaction mixture with carbon dioxide, and mixing the resulting homogeneous solution with fluorine-substituted or chlorofluoro-substituted hydrocarbons (US Pat. No. CA 2142195, 1996).

The disadvantages of the method are the large time spent on the process of obtaining the composition in a batch mode, the need to sequentially maintain the temperature at different stages of the process, which leads to additional costs of time and energy, as well as the high cost of manual labor and the complexity of automation of the process. In addition, the resulting product is contaminated with unreacted magnesium particles, which leads to the need for thorough cleaning.

Another embodiment for producing carbonated magnesium alcoholates described in US Pat. No. 4,318,963, 1982 involves dissolving a dry powder of magnesium alcoholate in alcohol with the introduction of carbon dioxide into the reaction system under a pressure of 150 kPa. If necessary, the resulting solutions are purified by filtration.

The disadvantages of the method are the large time spent on the process of obtaining the composition in a batch mode, the need to sequentially maintain the temperature at different stages of the process, which leads to additional costs of time and energy, as well as the high cost of manual labor and the complexity of automation of the process. In addition, the resulting product is contaminated with unreacted magnesium particles, which leads to the need for thorough cleaning.

Closest to the proposed technical solution is the method described in patent US 20040194902, 2004, the authors of which propose to obtain carbonated magnesium propylate by reacting a suspension of magnesium propylate with carbon dioxide. Carbonated Magnesium n-propylate (CH ₃ CH ₂ CH ₂ O) ₂ MgOCO is a white crystalline substance soluble in anhydrous n-propanol, as well as in other solvents of medium polarity. When exposed to water or humid air, carbonated magnesium n-propylate is hydrolyzed to produce magnesium carbonate, magnesium hydroxide (or basic magnesium carbonate) and n-propanol in accordance with the reaction equations:

2 (CH ₃ CH ₂ CH ₂ O) ₂ MgOCO + 3H ₂ O → Mg (OH) ₂ + MgCO ₃ + CO ₂ + 4CH ₃ CH ₂ CH ₂ OH

or

5 (CH ₃ CH ₂ CH ₂ O) ₂ MgOCO + 11H ₂ O → (MgCO ₃ ) ₄ ⋅ Mg (OH) ₂ ⋅ 5H ₂ O + CO ₂ + 10CH ₃ CH ₂ CH ₂ OH.

Carbonated n-propylate of magnesium actively interacts with acids with the release of carbon dioxide and n-propanol and the formation of magnesium salts in accordance with the reaction equation:

(CH ₃ CH ₂ CH ₂ O) ₂ MgOCO + 2H ⁺ → Mg ²⁺ + CO ₂ + 2CH ₃ CH ₂ CH ₂ OH.

An alcoholic solution of carbonated magnesium propylate, diluted with heptafluoropropane before use, is one of the most effective and popular reagents to reduce the acidity of paper.

The disadvantages of the method are the large time spent on the process of obtaining the composition in a batch mode, the need to sequentially maintain the temperature at different stages of the process, which leads to additional costs of time and energy, as well as the high cost of manual labor and the complexity of automation of the process. In addition, the resulting product is contaminated with unreacted magnesium particles, which leads to the need for thorough cleaning.

The technical problem of the present invention is to increase the efficiency of the method of obtaining a reagent to reduce the acidity of paper based on carbonized magnesium alcoholate or other magnesium alkoxides with the prevention of contamination of the target product with particles of unreacted magnesium.

The indicated technical problem is solved by the described method for producing a composition for processing pulp and paper products in a continuous or semi-continuous device consisting of a container for producing magnesium alcoholate, divided into sections for fractioning products and reagents by particle size, a container for concentrating magnesium alcoholate, a container for dissolving the alcoholate magnesium under the action of carbon dioxide, connected by lines of controlled mass transfer of products and reagents.

Achievable technical result is to obtain an alcoholic solution of carbonized magnesium alcoholate of a given concentration with higher productivity and efficiency (less time, labor and energy). The resulting reagent for paper processing in order to reduce acidity in operational properties is not inferior to similar reagents obtained in a batch reactor. This technical result is achieved by organizing a continuous or semi-continuous flow regime of the synthesis of the reagent, which reduces the time spent on loading / unloading the reagent and cleaning the reactor. A higher energy efficiency of the reagent synthesis compared to the known analogues is achieved by spacing the stages and structural elements with different temperature conditions in the space, which eliminates the need for periodic heating / cooling of the same structural elements and allows the process to be carried out under conditions of maintaining the set temperatures. In addition, the implementation of the temperature control mode reduces the time costs caused by the change of heating / cooling cycles. The controlled mass transfer between the elements of the installation determines the possibility of fine adjustment of the technological process in order to adjust the reaction yield and concentration of the final product. The introduction of magnesium alcoholate concentration block into the technological process allows its production in conditions of low concentrations of magnesium alcoholate and the predominance of the starting products. Under such conditions, a higher reaction rate is achieved.

The essence of the method is as follows.

A method of obtaining a composition for processing pulp and paper products is carried out in continuous or semi-continuous mode by contacting magnesium metal with alcohol to obtain a suspension of magnesium alcoholate in alcohol, concentrating the obtained suspension of magnesium alcoholate with the direction of the separated alcohol for recycling to contact with metal magnesium, dissolving the resulting concentrated suspension magnesium alcoholate by contacting the latter with carbon dioxide to obtain a solution of carbonized alk golyata magnesium that can be used as a composition for treating paper products, both independently and in admixture with an inert volatile solvent.

In this case, the contacting of magnesium metal with alcohol is carried out at a temperature of + 20 ° C to the boiling point of alcohol and the initial magnesium content in the reaction mixture is from 0.01% wt. up to 5.0% wt., preferably from 0.1% wt. up to 5.0% wt., while choosing the initial magnesium content, based on the desired reaction rate of magnesium with alcohol, and also for reasons of ensuring the safety of the process, since increasing the reaction rate of magnesium with alcohol increases the self-heating of the reaction mixture, which leads to increased risk of self-ignition of the resulting by-product - hydrogen gas. To ensure safe contact of metallic magnesium with alcohol, the reaction is carried out in an inert gas atmosphere selected from a number of gases that do not react with metallic magnesium, for example, helium or argon. Most preferably, an initial magnesium content of 1.0 wt.% Is selected. up to 5.0% wt., for example, 2.5% wt. As a result of contacting, a suspension of magnesium alcoholate in alcohol with a magnesium alcoholate content of 1% wt. up to 20% wt., concentration of the obtained suspension of magnesium alcoholate to the content of magnesium alcoholate in a concentrated suspension of 2% wt. up to 40 wt.%, but not less than 2 times greater than the initial content of magnesium alcoholate in suspension, by distillation of excess alcohol with the direction of the latter for recycling for contact with metallic magnesium, dissolving the concentrated suspension of magnesium alcoholate by contacting the latter with dioxide carbon at a temperature of + 20 ° C to the boiling point of alcohol to obtain a solution of carbonated magnesium alcoholate with a content of carbonated magnesium alcoholate from 3.0% wt. up to 25% wt., cooling the resulting solution of carbonized magnesium alcoholate to a temperature below the boiling point of a volatile solvent selected from halogenated hydrocarbons, and mixing the resulting solution of carbonized magnesium alcoholate with the indicated volatile solvent in a mass ratio of from 1: 4 to 1:20 to obtain the target a product with a carbonated magnesium alcoholate content of 0.15% wt. up to 7% wt.

In this case, the contact of metallic magnesium with alcohol is carried out under stirring with the separation of large particles of unreacted metallic magnesium and the addition of alcohol to completely dissolve the fine particles of metallic magnesium, thereby providing a suspension of magnesium alcoholate not contaminated with magnesium metallic particles.

The alcohol used is a monohydric alcohol containing from 1 to 5 carbon atoms, for example, methanol, ethanol, n-propanol, isopropyl alcohol, n-butanol, sec-butanol, tert-butanol, amyl alcohol, isoamyl alcohol.

In this case, a halogen-substituted hydrocarbon selected from a number of chlorine-substituted, fluorine-substituted, or chlorofluoro-substituted hydrocarbons having at least one hydrogen atom, or a mixture of such halogenated hydrocarbons is used as a volatile solvent. Preferably, difluorochloroethane, trifluorochloroethane, or heptafluoropropane is used.

A method of obtaining a composition for processing pulp and paper products can be illustrated by the equations of chemical reactions for the example of obtaining carbonated n-propylate of magnesium. At the first stage, magnesium propylate is synthesized from propanol and magnesium shavings (or granules) at the boiling point of propanol in accordance with the reaction equations:

In the second stage, the magnesium propylate dispersion interacts with carbon dioxide (gas or dry ice) in accordance with the reaction equations:

Both reactions are exothermic. The first of these reactions proceeds upon boiling of the reaction mixture after activation of the magnesium surface with iodine or alkyl bromide. The second reaction proceeds spontaneously and leads to heating of the reaction mixture several tens of degrees above the original value. It is not allowed to increase the temperature of the reaction mixture in the second reaction above 50 ° C.

The stages are separated in space and are carried out in parallel, while the magnesium propylate formed in the first stage is continuously supplied from the upper part of the reactor through the concentration unit to the second stage.

The first stage of the reaction is carried out in a vertical column (glass / metal), the inner part of which is divided by filter elements of different dispersion (inert polymer or metal mesh) into vertical sections of equal volume (from 1 to 100 l, for example, 50 l). In this case, all sieves have different cell sizes and are arranged in order of decreasing cell size when moving from the lower section to the upper. The number of sections is from 2 to 10, for example, 5 sections. The sections are separated by sieves with a mesh diameter of 1 mm to 10 μm (for example, 4 sieves between 5 sections with a mesh diameter of 1 mm, 200 μm, 50 μm, 10 μm). The heating of the column is carried out due to the circulation of the coolant along the outer contour of the column (column shirt). The temperature of the coolant is controlled by an external automated thermostat, which receives information on the temperature of the reaction medium from sensors in each section of the column. The feedstock (magnesium chips and propanol) enter the lower section, where the formation of magnesium propylate in the form of a precipitate takes place. Hydrogen gas evolved in this case flows vertically through the upper sections and the screens separating them, facilitating the transfer of the precipitate of magnesium propylate formed to the upper sections, and is removed from the reaction volume through a reflux condenser. In this case, the initial magnesium shavings remain in the lower section until their sizes are reduced due to the reaction to the level of throughput of the sieve separating the first and second sections (counting from the bottom up). Since the filter throughput decreases when moving to the upper sections, and also taking into account the fact that the reaction of magnesium particles with propanol continues in each section, and when the size of magnesium particles decreases, the reaction accelerates, the magnesium metal content in the upper section tends to zero.

As the reaction proceeds, the upper section is gradually enriched with a dispersion of magnesium propylate, which is transported by a peristaltic pump into a cube to concentrate magnesium propylate. The volume of the reaction medium of the first stage is maintained by the feed of propanol entering the lower section. The concentration of magnesium propylate in propanol is carried out by distillation of a portion of the solvent (propanol), which is combined with an additional portion of the starting components (propanol and magnesium) and fed back to the column for the synthesis of magnesium propylate in the lower section. By adjusting the rate of propanol distillation from the concentration unit, the magnitude of the flow of magnesium propylate suspension coming from the first stage unit and the amount of the additional stream of the starting reagents (magnesium and propanol) entering the lower section of the first stage reactor, the concentration of magnesium propylate in propanol, the flow of which It is continuously transported by a pump from the concentration unit to a container to produce carbonated magnesium propylate.

Obtaining carbonized magnesium propylate is carried out through the interaction of the precipitate of magnesium propylate with a sparged dried carbon dioxide, accompanied by the dissolution of the precipitate of magnesium propylate. The bottom (or lower part of the side wall) of the block for producing carbonated magnesium propylate is made of a filter with a throughput of 1 μm, through which the solution of carbonized magnesium propylate is supplied to a container for collecting the final product adjacent to this block, while the precipitate of magnesium propylate remains in the block for obtaining carbonated magnesium propylate. The flow of the final product is set equal to the flow of magnesium propylate transported from the block for the concentration of magnesium propylate and is regulated by an additional pump. Instead of gaseous carbon dioxide, it is possible to use solid carbon dioxide (in the form of dry ice).

For the synthesis, propanol dehydrated with a purity of at least 99.5%, magnesium in the form of flakes or silver-white chips with a size of no more than 10 × 1 × 1 mm and a purity of at least 99.9%, carbon dioxide with a volume fraction of not less than 99 are used , 9% and mass concentration of water vapor at a temperature of 20 ° C and a pressure of 101.3 kPa not more than 0.015 g / m ³ .

In addition to the carbonated magnesium propylate in the described manner using the described flow reactor, it is also possible to obtain other carbonated magnesium alcoholates from the corresponding alcohols, for example magnesium methyl carbonate methyl ethylate, magnesium ethyl carbonate ethylate, magnesium isopropyl carbonate isopropylate.

The method is carried out using the device shown in FIG. 1. A device for implementing a method for producing a composition for processing pulp and paper products is interconnected: a container 1 for contacting magnesium metal with alcohol, a container 2 for concentrating a suspension of magnesium alcoholate, a container 3 for contacting a suspension of magnesium alcoholate with carbon dioxide, a container 4 for mixing a solution of carbonated magnesium alcoholate with a volatile inert solvent. Moreover, the tank 1 for contacting magnesium metal with alcohol is equipped with heating means from + 20 ° С to the boiling point of alcohol, a reflux condenser, an agitator, means of supplying an inert gas, and is divided into at least two sections by a sieve or a set of sieves with a successively decreasing cell size such so that the addition of metallic magnesium is carried out in the section separated by a sieve with the largest mesh size, and the suspension of magnesium alcoholate is carried out from the section separated by a sieve with the smallest mesh size. At the same time, the container 2 for concentrating a suspension of magnesium alcoholate is equipped with means for heating to the boiling point of the alcohol and a direct refrigerator for condensing the distilled alcohol and recycling it into the tank 1 for contacting the magnesium metal with alcohol. At the same time, the container 3 for contacting the suspension of magnesium alcoholate with carbon dioxide is equipped with means to maintain a constant temperature from + 20 ° С to the boiling point of alcohol and is divided by sieve 6 into two or more sections so that carbon dioxide can be supplied by bubbling carbon dioxide gas and by adding solid carbon dioxide to the first section, to which a suspension of magnesium alcoholate is also fed, and the selection of a solution of carbonized magnesium alcoholate is carried out from the second oh section. Moreover, the tank 4 for mixing a solution of carbonated magnesium alcoholate with a volatile inert solvent is equipped with means for cooling the mixture from an initial temperature to a temperature below the boiling point of a volatile solvent.

When implementing the method in the tank 1 serves raw material A, which is a metal magnesium and alcohol. When metallic magnesium is contacted with alcohol, a suspension of magnesium alcoholate in alcohol B is formed, which is supplied to tank 2. In tank 2, alcohol C is distilled off, which is recycled to tank 1. A concentrated suspension of magnesium alcoholate in alcohol D is fed to tank 3, which also carbon dioxide E is supplied as a gas or as a solid (“dry ice”). When a suspension of magnesium alcoholate in alcohol is contacted with carbon dioxide, a solution of carbonated magnesium alcoholate in alcohol F is formed, which is fed into a container 4, which also contains volatile solvent G. After mixing a solution of carbonized magnesium alcoholate in alcohol with a volatile solvent, the desired product N is obtained. capacity 1 is divided into sections by sieves 5 with different cell sizes, which are arranged in order of decreasing cell size when moving from the lower section to the upper.

Below are examples illustrating the described method, but not limiting it.

Example 1

An inert gas (nitrogen) is blown through a flow reactor consisting of a block for the synthesis of magnesium propylate with a volume of 250 l, divided into 5 sections of 50 l sieves with a mesh diameter of 1 mm, 200 μm, 50 μm, 10 μm (block 1), a block for concentration 20 l (block 2), a block for producing carbonated magnesium propylate with a volume of 20 l (block 3). Block 1 is filled with dehydrated n-propanol with a purity of not less than 99.5% of a volume of 200 l, blocks 2 and 3 are filled with 10 l of n-propanol. 1.5 kg of magnesium in the form of chips with a size of about 10 × 1 × 1 mm and 1 l of a solution of iodine in n-propanol with a concentration of 50 g / l are loaded into the lower section of block 1. The mixture is brought to a boil (approximately 96 ° C), after which the mixture decolours and intense gas formation occurs. The necessary flow is established between blocks 1 and 2 and the intensity of distillation of alcohol from block 2 equal to this flow is changed. After 1 h, the flow values are changed so that the rate of distillation from block 2 is less than the flow from block 1 to block 2 by the amount of flow from block 2 to block 3. The same value is set to enter an additional amount of propanol into block 1. Periodically (every 30-60 minutes) a sample is taken from the flow between blocks 2 and 3, and the content of magnesium propylate is estimated by gravimetric method using centrifugation or filtration. I, and based on this value, the magnitudes of the flows change. The total productivity of the process is 12 l / h of a solution of carbonized magnesium propylate in propanol with a concentration of 20% by weight, which is greater than the productivity of a similar process in a batch reactor with a volume of 250 l.

Example 2

Similar to example 1 except for the use of magnesium in the form of granules with a diameter in the range of 0.1-1.0 mm The reactor unit 1 is divided into 10 sections with a volume of 25 L sieves with mesh sizes of 500 μm, 400 μm, 300 μm, 200 μm, 100 μm, 80 μm, 50 μm, 30 μm, 10 μm. The total productivity of the process is 12 l / h of a solution of carbonated magnesium propylate in propanol with a concentration of 20% wt.

Example 3

Similar to example 1, but the dried isopropyl alcohol with a purity of at least 99.5% was used as the alcohol, the reaction was carried out at a temperature of + 82 ° C. The total productivity of the process is 12 l / h of a solution of carbonated magnesium isopropylate in isopropyl alcohol with a concentration of 20% wt.

Example 4

Similar to example 1, but as the alcohol used is dried methyl alcohol with a purity of at least 99.5%, magnesium is loaded in an amount of 0.5 kg, and the reaction is carried out at a temperature of + 67 ° C. The total productivity of the process is 7 l / h of a solution of carbonated magnesium methylate in methanol with a concentration of 11% wt.

Example 5

Similar to example 1, but as the alcohol used is dried ethyl alcohol with a purity of not less than 99.5%, magnesium is loaded in an amount of 1.0 kg, and the reaction is carried out at a temperature of + 78 ° C. The total productivity of the process is 9 l / h of a solution of carbonated magnesium propylate in propanol with a concentration of 15% wt.

Claims (6)

1. A method of obtaining a composition for processing pulp and paper products by contacting magnesium metal with alcohol in an inert gas atmosphere at a temperature of + 20 ° C to the boiling point of alcohol and the initial magnesium content in the reaction mixture is from 0.01% wt. up to 5.0% wt. with the suspension of magnesium alcoholate in alcohol with a magnesium alcoholate content of 1% wt. up to 20% wt., concentration of the obtained suspension of magnesium alcoholate to the content of magnesium alcoholate in a concentrated suspension of 2% wt. up to 40 wt.%, but not less than 2 times greater than the initial content of magnesium alcoholate in suspension, by distillation of excess alcohol with the direction of the latter for recycling for contact with metallic magnesium, dissolving the concentrated suspension of magnesium alcoholate by contacting the latter with dioxide carbon at a temperature of + 20 ° C to the boiling point of alcohol to obtain a solution of carbonated magnesium alcoholate in alcohol, which is then mixed with a volatile solvent selected from halogen nzameschennyh hydrocarbons to obtain the desired product with a carbonated magnesium alkoxide of from 3.0% by weight. up to 25% wt. 2. The method according to p. 1, characterized in that the resulting solution of carbonized magnesium alcoholate is cooled to a temperature below the boiling point of the volatile solvent selected from halogenated hydrocarbons, and the resulting solution of carbonated magnesium alcoholate is mixed with the indicated volatile solvent in a mass ratio of from 1: 4 to 1:20 to obtain the target product with a carbonated magnesium alcoholate content of 0.15% wt. up to 7% wt. 3. The method according to any one of paragraphs. 1-2, characterized in that the contacting of metallic magnesium with alcohol is carried out under stirring with the separation of large particles of unreacted metallic magnesium and the addition of alcohol to completely dissolve the fine particles of metallic magnesium. 4. The method according to any one of paragraphs. 1-3, characterized in that the alcohol used is a monohydric alcohol containing from 1 to 5 carbon atoms. 5. The method according to any one of paragraphs. 1-4, characterized in that as a volatile solvent use a halogenated hydrocarbon selected from a number of chlorine substituted, fluorine substituted, or chlorofluoro substituted hydrocarbons having at least one hydrogen atom, or a mixture of such halogenated hydrocarbons. 6. Device for implementing the method according to any one of paragraphs. 1-5, which are interconnected containers for contacting magnesium metal with alcohol, for concentrating a suspension of magnesium alcoholate, for contacting a suspension of magnesium alcoholate with carbon dioxide, for mixing a solution of carbonated magnesium alcoholate with a volatile inert solvent, while the container for contacting magnesium metal with alcohol is equipped with inert gas supply means, heating means from + 20 ° С to the boiling point of alcohol, reflux condenser, stirrer, and is divided into sections with a set of sieves with a successively decreasing mesh size so that the addition of metallic magnesium is carried out in the section separated by the sieve with the largest mesh size, and the selection of magnesium alcoholate suspension is carried out from the section separated by the sieve with the smallest mesh size, also with a capacity for concentrating the alcoholate suspension magnesium is equipped with means for heating to the boiling point of alcohol and a direct refrigerator for condensing the distilled alcohol and recycling it to the contacting tank magnesium metal with alcohol, while the container for contacting a suspension of magnesium alcoholate with carbon dioxide is equipped with a means of maintaining a constant temperature from + 20 ° C to the boiling point of alcohol and is divided by a sieve into two sections so that carbon dioxide can be supplied by bubbling gaseous carbon dioxide, and by adding solid carbon dioxide to the first section, which also contains a suspension of magnesium alcoholate, and the selection of a solution of carbonized alcoholate agnya performed from the second section, and wherein the capacity for mixing a solution of carbonated magnesium alkoxide with a volatile inert solvent with means for cooling the mixture from an initial temperature to a temperature below the boiling volatile solvent.

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