Sodium diformate synthesis method

FIELD: chemistry.

SUBSTANCE: invention relates to a method of preparing a sodium formate-containing composition with formic acid content of not less than 35 % of the total weight of the said composition, in which a) a stream of formic acid with formic acid content of not less than 74 wt % is provided; b) a stream of formic acid from step a) together with sodium formate-containing streams from step f) and step h) are taken to the crystallisation step where an aqueous solution is obtained at high temperature, where the said solution has molar ratio HCOOH:Na[HCOO] greater than 1.5:1 and molar ratio HCOOH: H₂O equal to at least 1.1:1; c) at the crystallisation step the aqueous solution from step b) is crystallised to obtain a stream which contains a solid phase and a mother solution; d) the stream obtained from step c) is taken to a separation step on which the solid phase is separated from the mother solution to obtain a stream which contains sodium diformate and a stream which contains a mother solution; e) the stream which contains the mother solution from step d) is divided into two parts; f) one part of the stream from step c) in form of a portion (A) is returned to step b); g) the other part of the stream from step e) in form of a portion (B) together with the stream, including a base, which contains sodium is taken to a neutralisation step to obtain a mixture which contains sodium formate, and where portions of the mother solution (A) and (B) complement each other to 100 wt %, and the weight ratio of portion (A) of the mother solution to portion (B) lies between 20:1 and 1:10; and b) the sodium formate-containing mixture from step g) and optionally from step h), if necessary after its withdrawal, is taken to the concentration step in form of a stream where a portion of water contained in that stream is released, where after separation of the portion of water a stream which contains sodium formate is obtained, which is directly returned to step b) or crystallised at the second crystallisation and separation step, and the obtained liquid phase is taken to the concentration step h) in form of a stream, and the solid phase is taken in form of a stream to step b). The obtained product can be used in industrial production, especially at relatively low temperatures.

EFFECT: improved method of preparing a sodium formate-containing composition with formic acid content of not less than 35% of the total weight of the said composition; obtained product has antibacterial activity and is used in preservation for example, as well as for acidification of animal and plant material.

16 cl, 5 dwg, 7 ex, 8 tbl

The present invention concerns a method of obtaining a solid containing deformat sodium composition with a high content of formic acid.

Formic acid formate possess antimicrobial activity, their use, for example, for conservation and for acidification substances of vegetable and animal origin, such as herbs, agricultural products or meat, for processing biological waste or as a Supplement for animal feed.

In animal feed as compounds of sodium are used, as a rule, or a mixture of deformity sodium from trinacria-hydroformylation or one only of the latter, see, for example, international application WO 96/35337 and WO 04/57977. In the application WO 96/35337, in addition, report the use of deformity sodium, but not lead, however, no specific data on the receipt of this connection.

In General, for the use of hydrotreated preferably as high as possible the content of the formate anions as one of the active components. From an economic point of view is particularly useful if it's high content of formate anions combined with a high proportion of formic acid, since the latter provides acidifying effect. Taking into account these factors, the use of formic acid sodium formate is particularly beneficial for the Kolka as compared to trinacria-hydroformylation, and compared to potassium formate in each case, theoretically, there is a higher content of as ions, formate, and formic acid. Although diformate ammonium these values are still slightly more efficient, but deformat ammonium is an unstable connection.

Formic acid formate as such in solid form, and receive been known and are described, for example, in Gmelins Handbuch der anorganischen Chemie, 8th. Edition, Nummer 21, Seiten 816 to 819, Verlag Chemie GmbH, Berlin 1928, and Nummer 22, Seiten 919 to 921, Verlag Chemie GmbH, Berlin, 1937. According to these data, in principle, the acidic compound deformat potassium and deformat sodium is obtained by dissolution of potassium formate or sodium formic acid and subsequent cooling. In addition diformate sodium there is a stable crystalline form of trinacria-hydrotartrate. Refer, however, that deformat sodium in dry crystalline form is difficult to obtain, and in addition, it is relatively unstable. The data in the Gmelin Handbook can only be concluded that the products were not clean deformation sodium.

Publication of the German patent DE 424017 (14.01.1926) describes the synthesis of formic acid sodium formate with different content of acid by the introduction of sodium formate in aqueous formic acid. Thus, by cooling the solution to a temperature of the environment and the surrounding environment get the crystals. Depending on the content of water in formic acid, in addition to trinacria-hydroformed and mixtures of trinacria-hydrotreat with deformation sodium, supposedly it should be possible to obtain diformate sodium. The latter is obtained by the method according to patent DE 424017, if the content used in formic acid is more than 50%, for example 80%, as in example 2. Own experiments of the inventors have shown, however, that the net deformat sodium in crystalline form cannot be obtained under the conditions described in the patent DE 424017. When using this method are rather trinacria-hydroformed, the content of formic acid which is significantly below theoretical values in 40,36 wt.% of the total dry mass.

In the European patent EP 0824511 B1 describes a method for products containing salt with two salt-forming residues of formic acid. This mix certain formate, alkali metal or ammonium, hydroxides of alkali metals or ammonium, carbonate or bicarbonate or ammonia at a temperature from 40°C to 100°C with formic acid, the content of which is at least 50%. The mixture is then cooled, and salt with two salt-forming residues separated by filtration. Although in the example and lead the obtaining of formic acid potassium formate, and mixtures of formic acid Proc. of the sodium-hydrotreat, but the manufacture of solid pure diformate sodium, however, is not proposed. Temperature and concentrations to be used (water) solutions of potassium formate or sodium indicated for this method, allow to synthesize only deformat potassium, since (water) solutions of sodium formiate, due to lower than potassium formate limit of solubility cannot be obtained at the indicated concentrations. Accordingly, although deformat potassium to obtain and can, deformat sodium get only in a mixture with trinacria-hydroformylation.

Also in the European patent EP 0824511 B1 described variant of the method, in which the mother liquor obtained after crystallization, fully neutralized (pH 9 to 10) and evaporated, bringing the content of the formate to a value of 70-80%, and the thus obtained solution of the formate is served back to the original solution used for crystallization. To be able to use this method, described in the patent EP 0824511 B1 in the example of obtaining diformate potassium, to obtain diformate sodium, you need to work with a solution of sodium formiate, subject to evaporation at relatively high temperatures. For example, a solution of sodium formate with a concentration of 70 wt.% you can only get at a temperature of about 135°C, and the solution is of ormita sodium concentration of 80 wt.% - only at a temperature of about 180°C. These conditions require significant costs to maintain the temperature of the equipment used, such as pipes and fittings. If after evaporation of a solution of sodium formate with a concentration of 80 wt.% served on the return and mix it, for example, with 85%formic acid, the crystallization of the obtained solution due to the high content of water is technically possible only with considerable effort. The crystallization temperature of this solution is below 20°C, which means, as a rule, the need for glamourati with significant energy consumption and cost. In addition, neutralization of all the mother liquor by the method described in patent EP 0824511 B1, precipitates too much sodium formate, so that the overall balance shows the need to remove the excess. When using formic acid, high concentrations of this also cannot be avoided.

In the German application DE 102005017089.7 first described a method of obtaining a solid diformate sodium content of formic acid of at least 35 wt.% in a clean, stable and dry.

Sufficient stability of formic acid sodium formate in solid form has a special importance from the point of view of ease of handling and suitability for storage, and from the point of view of who their production. In particular, it is undesirable large selection of formic acid contained in formic acid-sodium formate, because of its corrosiveness.

The advantage of deformity sodium in the field of animal feed is that it is not necessary, as it usually happens in other cases, separately add trace sodium in the form of NaCl, as deformat as such is a source of sodium. The high content of formic acid in diformate sodium compared to, for example, from trinacria-hydrotartrate limits the content of sodium ions. Low or limited cations, for example, including potassium ions, it is desirable insofar as the latter, especially in the case of animals with mono-gastric, in particular birds, causing increased fluid intake (drink) and, thus, lead to the dilution of faeces of animals, meaning they can have a diuretic effect.

The present invention allows to solve the problem consisting in the provision of a method of obtaining a solid containing deformat sodium composition mainly consisting of deformity sodium to avoid the above problems known from the prior art. In particular, it was necessary to create the possibility of returning the mother liquor in the process of obtaining that does not require the conclusion C is uchitelnoj proportion of sodium formiate. The method according to the invention have, in addition, to provide the possibility of obtaining such a composition, which has high content of formic acid and in which deformat sodium is present in a relatively stable and dry form with high purity, so that the method can be used in industrial production, especially at relatively low temperatures.

This problem was suddenly solved, highlighting the crystallization of the desired compound from the mixture of sodium formate with more than half molar excess of formic acid, maintaining the molar ratio of formic acid and water at least to 1.1:1, returning a portion of the mother liquor directly into the solution to be crystallized, and the other part before returning neutralizing.

The first object of the present invention, therefore, is a method of obtaining a solid containing deformat sodium composition containing formic acid of at least 35 wt.% from the total mass containing deformat sodium composition in which at elevated temperature to prepare an aqueous solution of sodium formate and at least 74 wt.%-Noah formic acid with a molar ratio of HCOOH:HCOONa more than 1.5:1 and the molar ratio of HCOOH:H₂O at least 1,1:1, carry out the crystallization of an aqueous solution and separated terbufos from the mother liquor, and

(i) the fraction (A) the mother liquor is used upon receipt of an aqueous solution, and

(ii) part (B) the mother liquor is introduced into the reaction with the base containing sodium, and the resulting mixture containing the sodium formiate, if necessary, after removal of a part thereof, and if necessary after concentration thereof, it is also used to obtain an aqueous solution; and

moreover, the share of the mother liquor (a) and (b) complement each other to 100 wt.%.

Used in the present invention the original substances - sodium formate and formic acid is commercially available and their use is possible without pre-processing.

According to the invention upon receipt of an aqueous solution using the mother liquor from crystallization. The share of the mother liquor (a) and (b) may represent the only source of sodium formate used in the method according to the invention. If, however, the mother liquor is not available, as in the case before using for the first time, for example, at the beginning of the continuous production, you can use technical sodium formate. For use in the present invention is suitable in this case as well, formate, sodium, eye-catching in the form of waste in the production of polyols. Similarly the production subject to the application of sodium formate in Sogno, for example, by the reaction of sodium hydroxide, carbonate or sodium bicarbonate with formic acid by reaction of carbon monoxide with a liquid sodium hydroxide or by reaction of methylformate with sodium hydroxide. In this embodiment, the method may, for example, dissolving a solid NaOH or concentrated aqueous solution, if necessary, cooling and/or mixing, preferably in concentrated formic acid. This favorable opportunity to choose the ratio of the original substances so that the components of the resulting mixture of formic acid, sodium formate and water - were already present in the above required molar ratio. Otherwise, it is necessary to eliminate the excess of formic acid and/or reducing the water content in the mixture by conventional means known to the expert, for example by evaporation, extraction, distillation and the like typically utilize formate sodium content HCOONa which is not less than 97 wt.% of the total mass used source of sodium formiate. It is preferable to use sodium formate containing less than 0.1 wt.%, and in particular less than 0.05 wt.%, in each case on the total weight of the used source of sodium formate, potassium ions. As soon as after the first step of crystallization (hereinafter referred to so is e as phase crystallization) appears the mother liquor, which you can use to obtain the aqueous solution, the proportion of (a) and neutralized fraction (B) the mother liquor is preferably serve as the only source of sodium formiate.

According to the invention using an aqueous solution of formic acid content of formic acid of at least 74 wt.% or concentrated formic acid. Under the concentrated formic acid in professional circles is commonly understood as formic acid, with its contents, comprising 94 wt.% or above, i.e. with a residual water content lower than 6 wt.%, in each case on the total weight of formic acid. The term "aqueous formic acid" refers to a solution of formic acid in water content of formic acid less than 94 wt.% from the total mass of water from formic acid. It is advisable to use an aqueous solution of formic acid having a concentration of at least 75 wt.%, preferably at least 80 wt.% and particularly preferably at least 90 wt.%. Extremely preferable to use concentrated formic acid content thereof, comprising at least 94 wt.%. It is advisable that the concentration of formic acid or formic acid, which was not more than 99 wt.%, and particularly preferably located in the range from 80 to 99 wt.%and especially in the range from 94 to 98 wt.%.

It is preferable to use concentrated or aqueous formic acid in the amount of at least 1.6 mol, in particular at least 1.8 mol, and in particular at least 2.0 mol HCOOH on mol HCOONa. It is preferable to apply to obtain an aqueous solution components at a molar ratio of HCOOH:HCOONa in the range from 1.6:1 to 3:1, and in particular in the range from 1.8:1 to 2.5:1.

It is preferable to apply to obtain an aqueous solution components at a molar ratio of HCOOH:H₂O constituting at least 1.5:1 and particularly preferably at least 1,8:1, very preferably, the ratio was situated in the range from 1.5:1 to 10:1, and in particular in the range from 1.8;1 to 6.1:1.

According to the invention an aqueous solution produce at elevated temperatures. This implies, as a rule, the temperature at least 30°C, in particular at least 40°C and in particular 50°C, and, as a rule, temperatures of 100°C, in particular 80°C, and in particular 70°C, do not exceed. Such an aqueous solution can be prepared by conventional means known to the expert, for example by mixing, emulsification or dissolution at elevated temperature, or using a combination of these methods. The sequence of the introduction of the original substance is of secondary importance. This is true both for the first " the way during which there is no mother solution, which could apply for a refund, and to feed parts of the stream (a) and (b) the mother liquor. It is advantageous if the mixing is carried out in such a way as to obtain a homogeneous liquid mixture of original substances subject to maintaining a molar ratio. Insofar as this homogeneous liquid mixture is an aqueous solution, for example, because not all components are completely dissolved, homogeneous liquid mixture is converted into an aqueous solution by increasing the temperature, preferably with stirring.

To implement the method according to the invention are, as a rule, therefore, in order to obtain water or concentrated (preferably concentrated) solution of formic acid. This formic acid, add sodium formate in solid form or in the form of aqueous solution or aqueous suspension, optionally together with additional formic acid. Alternatively, it is also possible mixing of the components in the reverse order. If in the latter case, use or introduce solid sodium formate, it is advisable by adding parts you want to use formic acid or part of a partial stream of (A) the mother liquor is first to create a mixture, suitable the La stirring or pumping, to which add the remaining quantity of formic acid.

Part (A) the volume of the mother liquor from step (i) is used for the manufacture of an aqueous solution, preferably in the form of a solution without processing. Of course, this part can be stored for some time and needs to use to obtain an aqueous solution at any time later. In this case, part (A) is used, for example, in the form of a solution or suspension, preferably in the form of a solution.

The mixture obtained in step (ii) after neutralization of the private volume (V) stock solution, is used to produce an aqueous solution, usually in the form of aqueous suspensions or solids. If necessary, the portion of the mixture output to use in obtaining an aqueous solution. Before use, it is advisable to partially or completely evaporate the mixture. Add the mixture in the manufacture of an aqueous solution in each case, in portions, for example in the form of 2, 3, 4 or more separate portions, which are added to the reaction mixture after each other, or continuously, i.e. with constant, decreasing or increasing speed. While adding occurs, as a rule, higher temperatures, so that additional heating is not required. Usually the temperature of the mixture and/or added solution can be adjusted so as to maintain the MCA and the temperature ranges from 30°C to 80°C, and in particular from 40°C to 70°C. it is Advisable that the temperature of the mixture did not exceed 65°C. To the invention it is essential that crystallization occurred from the aqueous solution. As described in greater detail below, in the solution before crystallization to enter the seed crystals.

During the addition of sodium formiate wise to the solution or suspension is in motion, for example to be mixed. The movement should continue after the introduction, at least to obtain an aqueous solution, and in General - until the end or interruption of crystallization.

According to the invention the mixing of the starting compounds can be carried out in equipment of all kinds, usually used to create a homogeneous liquid mixtures, such as in reactors, boilers, tubes, etc. in particular in tanks with agitators, especially in those located within the heat exchange surfaces. They are known to the specialist. To avoid corrosion, for example, in the case of reactors and boilers made of steel, it is advisable that the surface or walls in contact with formic acid, were covered resistant to acid protective layer, for example of Teflon^®or sheathed inside particularly resistant to acid alloyed grades of steel.

Then, preferably while continuing the stirring, run kristalli is the situation of an aqueous solution. This can be achieved, for example, by partial evaporation or cooling, preferably by cooling. If the crystallization is carried out or start or speed-controlled evaporation of the liquid phase, preferably under vacuum, it is necessary to ensure that the molar ratio of the components in the solution were to the point of crystallization, as defined previously. If the crystallization is carried out by cooling, then this should be done preferably slowly, appropriate for time period of one to several, for example up to 12 hours, in particular from 3 to 10 h, and in particular from 4 to 8 o'clock When bicrystalline of deformity sodium. Was reasonable to carry out cooling at a speed component of from about 2 to about 20 K/h, for example, about 5-15/h to achieve complete crystallization subject to allocation of connections, it is advisable to cool the aqueous solution for a specified period of time to a temperature below 20°C, for example about 15°C or less, or 10°C or below. In this case, as a rule, the temperature does not decrease below 0°C, and in particular below 5°C.

Turned out to be expedient to dissolve the crystals-germ or small crystals, formed after the beginning of crystallization by heating to a temperature SOS is alausa a maximum of 65°C, in particular located in the range from 25°C to 50°C, and then start the crystallization process repeated, if necessary, slow-cooling. When this re-cooling the rate of change of temperature is usually in the range from about 0.5 to about 20 K/h, for example 1-15/h, in particular from 2 to 15 K/h, especially from 5 to 10 K/h, and preferably does not exceed 25 K/h crystallization Temperature is within the above boundaries.

In addition, it may be appropriate to facilitate the process of crystallization, i.e. in order of the so-called "priming", add an aqueous solution of existing crystals diformate sodium, such as previously obtained by the method according to the invention. Such crystals can be added in dry or wet form, suspended in a liquid, for example water or formic acid, phase, or a combination of these forms. The addition is carried out at a temperature exceeding that leads to the formation of crystals, but below that at which there is a homogeneous solution. The temperature of the reaction mixture by adding crystals, therefore, should not normally exceed 65°C and should preferably be in the range from 25 to 50°C. the crystallization Process can in this case, as described above, to occur at a cooling rate ranging from about 0.5 to when is Erno 20 K/h, for example 1-15/h, in particular from 2 to 15 K/h, especially from 5 to 10 K/h, and preferably not exceeding 25/hour, the crystallization Temperature is in the above bounds.

After crystallization of the resulting solid product is separated from the mother liquor. The separation of the solid phase from the mother liquor can be performed in a conventional way known to the expert, for example by filtration or centrifugation, preferably by centrifugation, in particular, with the use of a centrifuge with a buoyancy device or top unloading. Thus obtained wet containing deformat sodium composition contains, as a rule, a small amount of formic acid, water and/or sodium formate. The content of formic acid in humid containing deformat part of the sodium is usually higher than the 40.3 wt.% and is, in particular, in the range from 40,7 to 42.5 wt.% of the total weight of the wet composition.

Then the wet product is dried by conventional means, for example in vacuum and/or moderate heating. Suitable for use in this case, dryers and drying methods known to the expert and are described, for example, in .röll, Trockner und Trocknungsverfahren, 2. Aufl., Springer Verlag, Berlin, 1978. In particular, it is possible to apply, for example, contact dryers, dryers with the vortex layer, spray dryers and spray dryers. It should consideration is given to the ü relatively high volatility contained in the product of formic acid, as well as the limited thermal stability of the product. During drying, the product temperature should not normally exceed 65°C, and in particular 50°C. the Proportion remaining in the product after drying of water (residual water content) is usually not more than 0.5 wt.% and is usually in the range from about 0.5 to 0.01 wt.%, preferably not greater than 0.3 wt.%, particularly preferably not higher than 0.2 wt.% and very preferably not higher than 0.1 wt.%, of the total mass, and the definition of conduct oxygenations by titration according to Karl Fischer (described, for example, Wiland, Wasserbestimmung durch Karl-Fischer-Titration, Darmstadt, GIT, 1985).

Here and below, the expression "the total weight of the formulation of deformity sodium is used as a synonym for the expression "the total dry weight". Under the total dry weight should be understood the weight of the formulation of deformity sodium obtained by drying the product at a temperature below its decomposition temperature, for example by drying for 1 hour at 35°C and a pressure of 50 mbar.

To implement the method according to the invention it is expedient to obtain crystallization of deformity sodium of the highest possible output, as it allows to minimize the flow of material inside the process. This makes it possible to reduce hardware costs, for example, using the apparatus smaller.

The mother liquor separated after cu is stylizacji, share according to the invention in two parts (a) and (B). Partial volume (A) with formic acid and treated according to step (ii) partial displacement (In), optionally after partial or complete mixing of the flows of substances, return to the stage of crystallization. It is possible intermediate storage of the partial volumes (a) and (b) in standard containers, such as tanks or boilers that allows you to control the dosage according to the need. The weight ratio of the partial volume (A) and partial volume (V) stock solution is preferably in the range from 20:1 to 1:10, more preferably in the range from 10:1 to 1:5, particularly preferably in the range from 8:1 to 1:2, and very preferably in the range from 5:1 to 1:1. From the respective molar concentrations of formic acid in parts (a) and (b) it is possible to determine the volumetric flow that must be set.

Partial volume (V) served on a stage of neutralization, where they perform a partial or full neutralization. Suitable base containing sodium is sodium hydroxide, sodium carbonate, sodium bicarbonate, alkanoate sodium with 1-6 carbon atoms, such as methanolic sodium, atenolol, propanolol, butanolate, pentanol and hexanol sodium and mixtures thereof. It is preferable to choose the Foundation of sodium hydroxide, sodium carbonate and with the Yessei. Foundation can be applied, for example, in the form of an aqueous solution. It is preferable to add to the partial volume (B) a solution containing a hydroxide and/or sodium carbonate, for example 50%sodium hydroxide solution, sodium carbonate solution with a concentration of from 20 to 30 wt.% or their mixture. It is advisable mainly to neutralize the partial volume (In) completely. "Mostly full" neutralization means in this case that the used amount of the base at least matches (number) present in the partial volume (V) of formic acid and, thus, theoretically enough to fully neutralize.

If necessary, the part obtained by neutralizing a mixture containing sodium formate, select and remove it. It may be necessary to remove the excess of sodium formate produced by neutralization, based on the total balance of formate. For the method according to the invention it is preferable that the share subject to the excretion of sodium formiate was small, because it provides the opportunity to optimize the implementation of the method and product yield. Typically, the displayed quantity should not exceed 20 wt.%, in particular not more than 10 wt.%, and especially not more than 5 wt.%, from the total mass of the mixture containing the sodium formate. It is reasonable to deduce that frequent the mixture, that the amount of sodium formate contained in the remaining part of the mixture, together with the amount of sodium formate contained in paragraph (a) of the mother liquor gave in the total amount of sodium formate used for the manufacture of an aqueous solution (i.e. in order not required to additionally introduce formate sodium).

The remaining part of the mixture obtained by neutralizing and containing sodium formate, is transferred to the stage of concentration, preferably at the stage of evaporation. At this stage, take part contained in a mixture of water, preferably by evaporation. The share of output produced by this water depends on what form must be returned to the step of crystallization of the sodium formate contained in the mixture. This can be accomplished, for example, in the form of a solution, suspension or solid. It is preferable to perform the check in a form suitable for pumping slurries or solids, which optionally also contains some residual moisture. Obtained at the stage of concentration and return the mixture containing sodium formate, is characterized, as a rule, the content of sodium formiate, comprising at least 50 wt.%, in particular, at least 60 wt.%, in particular lying in the range from 50 to 100 wt.%, and very-specific - in the range of from 70 to 90 wt.%, in each case, by weight of the total return is my mix. The water content in the mixture is preferably not more than 25 wt.% and particularly preferably not more than 15 wt.%, in each case on the total weight of the mixture. Received or processed mixture containing sodium formate, return to the stage of crystallization.

Reducing the water content can also be achieved by using the second stage of crystallization, which receive the second solid phase and a second mother liquor, and the second stage of concentration, in which the second solid phase is separated from the second mother liquor. After this, the second solid phase is sodium formate. The conditions of crystallization is known to the expert and are described, for example, Zagidullin, S.., et al., "Investigation of Supersaturations in the Sodium Formate - Water System to Optimize Crystallization", Russian Journal of Applied Chemistry, Vol.69 (1996), 5, 669-672. For example, it is possible to carry out crystallization by evaporation or crystallization by cooling with cooling walls or evaporative cooling. Note that at low temperatures, for example below 30°C or below 20°C, may yet to crystallize hydrated forms of sodium formate containing more than one molecule of H₂O bound as water of crystallization, per mole of sodium formate. This is generally undesirable, and therefore this should be avoided, especially by crystallization at higher temperatures.

The resulting straterra phase may contain less water - 15 wt.%, in particular less than 10 wt.%, and in particular less than 5 wt.%. A special advantage of this low water content is that the crystallization of deformity sodium can be performed at low water content, for example less than 10 wt.%, from the aqueous solution from which to carry out crystallization. This makes it possible to provide a higher crystallization temperature and a higher output at a fixed finite temperature.

The method according to the invention can be implemented particularly expedient, if the number of mol of formic acid contained in the partial volume (In), approximately corresponds to the number of mol of deformity sodium (and, if necessary, sodium formate, which may stick to the product, in particular, due to a residual moisture content), the output flow of the product, or only slightly greater than it, i.e. if the molar ratio of these components is about 1:1. In this case, you can get all necessary for the use of sodium formate by return flows of material, without the need for excretion of excess sodium formate. In this part of sodium formiate again enter into the process by returning the mother liquor. The remaining part can completely ensure the return neutralized or concentrated part (B)the mother liquor. To implement this alternative method, the ratio of part (a) and part (B) the mother liquor should normally be set so that the molar ratio of HCOOH in part (B) the mother liquor and the total number of substances diformate sodium and possibly formate sodium contained in the solid phase, prior to the drying of the solid phase, which is optionally carried out after this, was not more than 1.2:1, preferably not more than 1.1:1 and particularly preferably not more of 1.05:1.

In a preferred form of execution of the act as follows:

a) ensure the flow (1) formic acid content of formic acid is not less than 74 wt.%;

b) stream (1) from step a) together with two containing formate sodium flows (5A) and (10) serves on the stage of crystallization, and receive, if necessary, increasing the temperature, an aqueous solution, characterized by a molar ratio of HCOOH:Na[HCOO], greater than 1.5:1, and the molar ratio of HCOOH:H₂O, constituting not less than 1.1:1;

c) at the stage of crystallization carry out the crystallization of the aqueous solution from step b) receiving stream (3)containing a solid phase and a mother liquor;

d) stream (3) from step (C) serves on the phase separation, in which the solid phase is separated from the mother liquor, and receive the stream (4)containing deformat sodium, and flow (5)containing methacrylates;

e) divide the stream (5) from step d) into two parts (5A) and (5b);

f) flow (5A) from step e) in the form of partial volume (A) return to step (b);

(g) flow (5b) from step e) in the form of partial volume (V) with a flow (6), includes a base containing sodium, serves on the stage of neutralization, thus obtaining a mixture containing sodium formate; and

h) served with step g), the mixture containing the sodium formiate, if necessary after removal of a part thereof in the form of a thread (7a), in the form of a stream (7) on the stage of concentration, which remove part of the water contained in the stream (7), in the form of a stream (9), and receive containing sodium formate stream (10), which return to step b).

Schematic representation of the method corresponding to this preferred form of execution shown on the attached figure 2. Mixing of currents (5A) and (10) flow (1) in step b) can occur before or after the filing of the stage of crystallization, for example before filing so that the flow of (1) first enter the stream (10), and then thread (5A). Of course, threads (5A) and (10) can also be mixed with each other before joining thread (1) or to the feed stage of crystallization.

Usually in this form of execution at the step d) stream (5) mainly contains formic acid concentration in the range from 35 to 80 wt.%, particularly preferably in the range from 40 to 75 wt.%; the sodium formate with the end of the acidity in the range from 20 to 45 wt.%, particularly preferably in the range from 20 to 40 wt.%; and the water content is in the range from 0 to 30 wt.%, particularly preferably in the range from 5 to 25 wt.%; in each case on the total weight of the stream (5). In step g) as stream (6) it is advisable to use an aqueous solution containing sodium hydroxide, carbonate and/or sodium bicarbonate. A particularly preferred aqueous sodium hydroxide solution with a content of NaOH in the range from 10 to 60 wt.%, and preferably in the range from 20 to 55 wt.%, in each case on the total weight aqueous solution of caustic soda. Stream (10) from step h) typically contains sodium formate concentration in the range from 50 to 100 wt.%, preferably in the range from 55 to 95 wt.% and particularly preferably in the range from 70 to 90 wt.%; and water, the content of which ranges from 0 to 50 wt.%, preferably in the range of 5 to 45 wt.% and particularly preferably in the range from 10 to 30 wt.%, in each case on the total mass flow (10).

The expression "mainly" in this case means that the stream does not contain any significant amounts of other substances. In the stream (5) may, for example, be a small number of small crystals diformate sodium, which were not separated in the separation of the phases on the phase separation or formed again after the split. Typically, however, the share of other substances in streams (5) and (10 should not exceed 5 wt.%, and in particular - 3 wt.%.

In another preferred form of execution of the thread (10) from step h)containing sodium formate, before returning to step b) is served on the second stage of crystallization and phase separation. Detailed description is as follows:

k) stream (10) from step h)containing sodium formate, before returning to step b) is served on the second stage of crystallization and in the framework of this stage are crystallization to obtain a second solid phase and a second mother liquor;

l) a second solid phase and a second mother liquor obtained in step (k), served in the form of thread (12) on the phase separation, in which the second solid phase is separated from the second mother liquor, and receive contains a second mother liquor stream (13) and containing sodium formate stream (14);

m) return stream (14)containing sodium formate, from step l) on stage b) and use it there as a stream (10); and

n) containing mother liquor stream (13) from step l)

n1) return to step (h) and it serves it along with the flow (7) on the stage of crystallization of step (h);

n2) return to step (k) and serves it with the thread (10) on the second stage of crystallization;

n3) is divided into partial flows (13A) and (13b), a partial stream of (13A) return to step (h) and it serves it along with the flow (7) on the stage of crystallization of step (h)and flow (13b) return to step (k) and the here and submit it together with the stream (10) at the second stage of crystallization; and/or

n4) partially remove this thread and remove it.

Schematic display method corresponding to this preferred form of execution shown in Fig, 3, 4, and 5.

Usually in this form of execution stream (13) from step l), comprising the mother liquor contains mostly water, with a share ranging from 20 to 60 wt.%, preferably in the range from 25 to 55 wt.% and particularly preferably in the range from 30 to 50 wt.%; and formate sodium concentration in the range from 40 to 80 wt.%, preferably in the range of 45 to 75 wt.% and particularly preferably in the range from 50 to 70 wt.%, in each case on the total mass flow (13). It is advisable to file containing mother liquor stream (13) from step l), or according to stage n1) back to step (h), or according to the stage n2) back to step (k). At stage h) returned thread (13) can be connected with the flow (7) receiving stream (8); then the stream (8) serves to phase concentration step h). Of course, the thread (7) and returned to the stream (13) can also apply for phase concentration separately. At stage k) returned thread (13) may be combined with stream (10) receiving stream (11); then the stream (11) serves for the second stage of concentration step k). Of course, the thread (10) and return flow (13) can also apply for phase concentration separately. If necessary, the stream (13) from step l) partially withdraw as determined in step n4) and taking the seized this partial stream. It should, as a rule, to withhold and withdraw no more than 30 wt.%, in particular not more than 20 wt.%, and in particular not more than 10 wt.%, from the total mass flow (13). As a rule, there should be a partial seizure containing mother liquor stream (13) from step l) only to the extent that it is necessary to regulate the balance of substances, in particular water content. Preferably in step n) the withdrawal of part of the stream (13) according to step n4) does not hold. Usually the stream (14) from step l), carrying formate, sodium, and contains primarily sodium formate concentration in the range from 75 to 100 wt.%, in particular in the range from 90 to 99 wt.%, and especially in the range from 95 to 98 wt.%; and the water content in the range from 0 to 25 wt.%, in particular in the range from 1 to 10 wt.%, and especially in the range from 2 to 5 wt.%, in each case on the total mass flow (14).

The expression "mainly" in this case means that the stream does not contain any significant amounts of other substances. Typically, however, the share of other substances in the threads (13) and (14) shall not exceed 5 wt.%, and in particular - 3 wt.%.

The method according to the invention can be implemented continuously, semi-continuous or periodically.

Solid containing deformat sodium composition obtained by the method according to the invention has a high purity and therefore after drying, you characterized akim content of formic acid, as a rule, at least 35 wt.%, often - not less than 36 wt.%, in particular at least 37 wt.%, especially not less than 38 wt.%, it is highly desirable to 39 wt.%, and even more preferably at least 40 wt.%, in each case on the total mass containing deformat sodium composition. As a rule, the content of formic acid obtained according to the invention containing deformat sodium composition should not exceed 41 wt.%, and in particular - of 40.5 wt.%, in each case the total weight. It is desirable that the content was in the range of from 38 to 41 wt.%, particularly preferably in the range from 39 to 40.5 wt.%, and even more preferably in the range from 40 to 40.3 wt.%, in each case on the total mass obtained containing deformat sodium composition. The content of formic acid in dry product can be defined in the usual way, for example by titration of formic acid base. Naturally, the content of the formate anions in the dry product is also high.

Obtained according to the invention the formulation diformate sodium is usually crystalline form. I think that the recipe is mostly or completely corresponds to the formula HCOONa·HCOOH (deformat sodium), which, however, should not be construed as limiting the invention. For the invention it is much more important that the formulation contains sodium formate and formic acid in the associated crystal is practical form. Having obtained according to the invention, the crystalline modification diformate sodium can, for example, to determine angle x-ray scattering. Undesirable modification, such as trinacria-hydrotherapist, it is also possible to qualitatively detect with this method. The molar ratio of the components of sodium formate and formic acid in the composition should usually be in the range from 0.9:1 to 1.1:1, in particular in the range from 0.95:1 to 1.05:1, and in particular, about the same as 1:1. Share diformate sodium in the composition is usually not less than 97 wt.%, in particular at least 98 wt.%, and especially at least 99 wt.%, in each case on the total weight of the composition. Due to the presence of residual moisture, perhaps crystallized, the composition may contain other components such as up to 1.5 wt.% formic acid, up to 1.5 wt.% formate sodium and/or up to 0.5 wt.% water, in each case on the total weight of the composition. At a temperature of about 65°C using DSC (differential scanning calorimetry), it is possible to observe the phase transition point. The composition differs relatively low hygroscopicity, especially compared to trinacria-hydrotartrate. Besides containing deformat sodium composition obtained according to the invention, stable enough not to cause problems in handling and further processing. the moreover, the content of potassium ions in the resulting composition is a maximum of 1000 parts per million, and in particular not more than 500 parts per million, in each case on the total mass. The content of chlorides containing deformat sodium composition obtained according to the invention, for reasons associated with the receipt, usually less than 1500 parts per million, and in particular less than 1000 parts per million, in each case on the total mass.

The method according to the invention to obtain a dry solid containing deformat sodium composition in a stable crystalline form provides applicability conditions obtain on an industrial scale. In particular, it differs in that it provided an efficient way of removing water. This makes it possible, in particular, to maintain a low water content in the aqueous solution, subject crystallization, which leads to the above mentioned benefits.

The obtained solid product before and/or after the drying phase of grind, for example, using mortar, cutting perforated presses and rolling machines, glomerulopathy, for example, mixers and/or compacting, for example, presses and machines. Devices used for such grinding, the specialist known.

Depending on the desired purpose of possible further processing containing deformat sodium composition, poluchennogo is according to the invention, in particular it is possible to produce powders with a specific particle size, coating particles obtained by the shell and/or create a mixture with other additives. As a shell or coating materials include oils, such as soybean oil, fats and fatty acids, such as palmitic or stearic acid, or of polymeric membranes, for example, from polyalkylene and their derivatives. Conventional additives are, in particular, tools that facilitate the fluidity, such as silicic acid, etc. Conventional methods of coating, and it is also possible to use additives in principle well-known specialist in the relevant field, see, for example, German application DE 10231891 A1.

According to the invention containing deformat sodium personnel get in solid form, in particular in the form of a crystalline powder, or granulate, or compactata. Depending on requirements, due to the technique of application, the average particle size of powders, granules or compactata is in the range from 1 μm to 10000 μm, in particular from 10 μm to 5000 μm, and particularly from 100 μm to 2500 μm.

Manufactured according to the invention the solid containing deformat sodium composition or containing components and compositions suitable for use in animal feed, in particular as additives for animal feed (feed additives), and in particular as additives premixes on what I feed for animals. The premix is a mixture that usually contains minerals, vitamins, amino acids, trace elements, and - if necessary - enzymes. Animal feed and feed additives containing obtained according to the invention the solid containing deformat sodium composition, particularly suitable for animals with mono-gastric, such as pigs, especially piglets breeding sows and fattening pigs, and birds, particularly broilers, layers, turkeys, ducks, geese, quail, pheasants and ostriches.

Depending on what substances or additives contained in the feed or feed additive in addition, the contents are made according to the invention the solid containing deformat sodium composition in the feed or feed additive can significantly vary. Its content in feed additives, in addition, depends on the type of formulation, for example, from the addition of auxiliary substances, such as drying agents, from (possibly existing) coatings and residual moisture content. Usually the content is made according to the invention the solid containing deformat sodium composition in the feed additive is within, for example, from 0.1 to 99.5 wt.%, in particular from 0.5 to 75 wt.%, and especially from 1 to 50 wt.%, of the total dry weight of the feed additive. Manufactured according izobretatelny containing deformat sodium composition is also suitable for use in premix, and it can be used, for example, may be added in conventional amounts.

Low content of potassium ions is particularly suitable, in particular, when used in feed and feed additives for poultry, as in this case potassium may have a diuretic effect. Use is made according to the invention the solid containing deformat sodium composition for the above-mentioned objectives allows to provide, therefore, an acid source and sodium formate without unnecessarily increasing the proportion of potassium ions. Thus, it is possible to make a feed additive that contains solid containing diformate sodium composition made according to the invention, and generally does not contain potassium ions. The expression "mainly contains no potassium ions" in this case means that the content of potassium ions is a maximum of 1000 parts per million, and in particular not more than 500 parts per million, in each case on the total weight of the feed additive.

The composition of animal feed is selected in such a way that the best way to cover the appropriate nutritional needs for this species. In General as sources of raw protein is chosen herbal ingredients of the feed, such as corn, wheat or barley meal, meal, whole soybeans, soybean meal after extra the simulation, Flaxseed meal after extraction, rapeseed meal after extraction, herbal flour or pea meal. To ensure that the appropriate energy value of the feed, add soy butter or other animal or vegetable fats. Because vegetable protein sources contain only insufficient amounts of certain essential amino acids, feed often enriched with amino acids. It is primarily about lysine and methionine. To ensure the supply of agricultural animals in minerals and vitamins, also produced their add. The type and amount of added minerals and vitamins depend on animal species and are known to the expert (see, for example, Jeroch et al., Ernährung landwirtschaftlicher Nutztiere, Ulmer, UTB). To cover the needs for nutrients and energy, you can apply a complete feed that contain all the nutrients in the ratio covering needs. This may be the only food animals. Alternatively, you can add food-additive for feed grain cereal. When it comes to supplementing the feed-mixtures rich in protein, minerals and vitamins.

Manufactured according to the invention the solid containing deformat sodium composition particularly suitable for use as a so-called what about the acidifier. Poikilitically call such substances, which reduce the pH value. This definition covers both those substances that reduce the pH value in the substrate (e.g., animal feed), and those that reduce the pH in the gastrointestinal tract of the animal.

Manufactured according to the invention the solid containing deformat sodium composition particularly suitable for use as a means of stimulating productivity and/or growth. In a preferred form of execution of a solid containing deformat sodium composition is used as a tool for stimulating productivity and/or growth of animals mono-gastric, in particular pigs and/or poultry.

Manufactured according to the invention the solid formulation diformate sodium is also suitable for use as preservative, in particular preservative for grass meal and/or animal feed.

Obtained according to the invention the solid containing deformat sodium composition is useful for getting silo. It accelerates lactic acid fermentation, prevents the silo and inhibits the growth of harmful yeast, so they can be used as a means of silage (AIDS silage).

You can also use obtained according to the invention twingo containing the th deformat sodium composition as fertilizer.

Description of figures

In Fig. 1 presents a schematic representation of a variant of the method according to European patent EP 0824511 B1, wherein the mother solution after the neutralization of the return on the stage of crystallization. 1 mainly corresponds to figure 2 from the publication EP 0824511 B1, but the latter is not shown all of the thread (7a). In this embodiment, the way to get deformat sodium is possible only if in the reaction mixture, which should occur bicrystalline product, to set the molar ratio of formic acid and sodium formate and water, respectively, given for the method according to the invention.

Details of the technology presented in figure 1, are such that the formic acid serves as a stream (1) and mix it with containing formate sodium flow (10) receiving stream (2)representing the reaction mixture. The reaction mixture is served in the form of a stream (2) at the stage of crystallization, while receiving solids and mother liquor. Solids and mother liquor in the form of a stream (3) is directed to a phase separation in which the solid phase is separated from the mother liquor, and get containing deformat sodium stream (4) containing mother liquor stream (5). Stream (5) with the flow of caustic soda (6) is directed to the stage of neutralization, and get a mixture containing formate on the model. Part of this mixture is taken in the form of a stream (7a). The remainder in the form of a stream (7) is directed to the stage of concentration, in which the part is contained in the stream (7) water output in the form of a stream (9). It contains sodium formate stream (10), which return to step b).

Figure 2 presents a schematic representation of the version of the method according to the invention. Flow (5b) is neutralized, concentrated by evaporation and returned to the stage crystallization.

Details of the technology presented in figure 2, in General, are such that the formic acid serves as a stream (1) containing formic acid is not less than 74 wt.%. Thread (1) is combined with two containing formate sodium flows (5A) and (10) receiving stream (2). Thread (2) is served on the stage of crystallization, and, if necessary, increasing the temperature, gain an aqueous solution, characterized by a molar ratio of HCOOH:HCOONa, greater than 1.5:1, and the molar ratio of HCOOH:H₂O not less than 1.1:1. The aqueous solution is fed to the crystallization realized, for example, by evaporation and/or by lowering the temperature, while receiving solids and mother liquor. Solids and mother liquor in the form of a stream (3) is directed to a phase separation in which the solid phase is separated from the mother liquor. Containing deformat sodium flow (4) output. Containing Royal races of the thief thread (5) is divided into two partial flow (5A) and (5b). Thread (5A) in the form of shares (A) return to the stage of crystallization. Flow (5b) as a fraction (C) containing a hydroxide and/or sodium carbonate stream (6) serves on the stage of neutralization. The part obtained by neutralizing a mixture containing sodium formate, if necessary, taken in the form of a stream (7a). The remainder in the form of a stream (7) is directed to the stage of concentration, in which the part is contained in the stream (7) water output in the form of a stream (9). Obtained containing sodium formate stream (10) return to the stage of crystallization, which also serves threads (1) and (5A).

Figure 3 presents a schematic representation of the version of the method according to the invention. Flow (5b) is neutralized and concentrated by evaporation. The water content in the received stream (10)comprising sodium formate, before returning to the (first) stage of crystallization separately reduce the crystallization and separation of the phases.

Technology details presented on figure 3, in General, are such that the formic acid serves as a stream (1) containing formic acid is not less than 74 wt.%. Thread (1) is combined with two containing formate sodium flows (5A) and (14) receiving stream (2). Thread (2) is served on the stage of crystallization, and, if necessary, increasing the temperature, gain an aqueous solution, characterized by a molar ratio of HCOOH:Na[HCOO], higher than the surrounding 1,5:1, and the molar ratio of HCOOH:H₂O not less than 1.1:1. The aqueous solution is fed to the crystallization realized, for example, by evaporation and/or by lowering the temperature, while receiving solids and mother liquor. Solids and mother liquor in the form of a stream (3) is directed to the first stage of the separation on which the solid phase is separated from the mother liquor. Containing deformat sodium flow (4) output. Containing mother liquor stream (5) is divided into two partial flow (5A) and (5b). Thread (5A) in the form of shares (A) return to step b). Flow (5b) as a fraction (C) containing a hydroxide and/or sodium carbonate stream (6) serves on the stage of neutralization. The part obtained by neutralizing a mixture containing sodium formate, if necessary, select (not shown). The mixture is combined with containing formate sodium flow (13A)receiving stream (8). Thread (8) is directed to the stage of concentration, in which the part is contained in the stream (8) water output in the form of a stream (9). The water content in the received stream (10)comprising sodium formate, before returning to step b) reduced by taking the following measures. Stream (10) is combined with containing formate sodium flow (13b)receiving stream (11). Stream (11) serves for the second stage of crystallization, which in the stream (11) carry out crystallization to obtain a second solid phase and a second mother liquor, n is the sample, through evaporation or temperature reduction. The second solid phase and a second mother liquor is served in the form of thread (12) on the phase separation, in which the second solid phase is separated from the second mother liquor. It contains a second mother liquor stream (13) and containing formate sodium flow (14). Stream (14)containing sodium formate, return to the first stage of crystallization. Containing mother liquor stream (13) is divided into partial flows (13A) and (13b). A partial stream of (13A) connected to the stream (7)receiving stream (8). Thread (8) is directed to phase concentration (evaporation). A partial stream of (13b) is combined with the stream (10)receiving stream (11). Stream (11) serves for the second stage of crystallization. In this embodiment, the method further possible partial withdrawal and the withdrawal of the thread (13) (not shown).

Figure 4 presents a schematic representation of the version of the method according to the invention shown in figure 3. In this embodiment, the second stage separation also receive contains a second mother liquor stream (13) and containing formate sodium flow (14). Containing formate sodium stream (14) also return for the first stage of crystallization. Containing mother liquor stream (13) is combined with the stream (7)receiving stream (8). Thread (8) serves on the stage of concentration (evaporation). In this embodiment of the method updat the additional partial withdrawal and the withdrawal of the thread (13) (not shown).

Figure 5 presents a schematic representation of the version of the method according to the invention shown in figure 3. In this embodiment, the second stage separation also receive contains a second mother liquor stream (13) and containing formate sodium flow (14). Containing formate sodium stream (14) also return for the first stage of crystallization. Containing mother liquor stream (13) is combined with the stream (10)receiving stream (11). Stream (11) serves for the second stage of crystallization. In this embodiment, the method further possible partial withdrawal and the withdrawal of the thread (13) (not shown).

The following examples are intended to illustrate the invention and in no case do not restrict it.

Examples

I. Manufacture of formulations of deformity sodium without returning the mother liquor (control examples)

Control examples I.1 and I.2 implement in a vessel with stirrer capacity of 1 l, equipped with devices for heating and cooling, as well as runoff. The molar ratio of components in the underlying crystallization of the aqueous solution in each case corresponds to the values that must be set by the method according to the invention.

Reference example I.1 (according to the German patent application DE 102005017089.7)

650 g of an aqueous solution of formic acid with a concentration of 94 wt.% put in a vessel and stirring, was heated to 55°C. P is remesiana continued throughout the experiment. In a solution of formic acid dissolved in 350 g of solid sodium formate (purity>97%), and received a clear solution. Then the solution was slowly cooled. After about 4 h, reached a temperature of around 12°C, at which the observed sudden precipitation. The suspension is heated to a temperature of about 35°C, while [not reduced sediment to] the observed light turbidity. Then the suspension for about 6 hours and cooled to a temperature of 20°C and poured from a vessel with a stirrer. The mother liquor separated from the crystals with suction filter. The output of the solid containing deformat sodium composition was OK. 125, After drying in a vacuum drying Cabinet at a temperature of 35°C the residual water content in the product amounted to about 0.1 wt.% of the total dry matter equal to 122, the Content of formic acid in a dry product made up of 40.3 wt.% of the total dry mass.

Reference example I.2 (according to German patent DE 102005017089.7)

650 g of an aqueous solution of formic acid with a concentration of 80 wt.% put in a vessel and stirring, was heated to 55°C. while Continuing to mix, in a solution of formic acid dissolved 430 g of solid sodium formate (purity>97%), and received a clear solution. Then the solution was slowly cooled. After about 5 h reached a temperature of around 24°C, at which the observed sudden precipitation. Suspension, PE is anesiva, heated to a temperature of about 35°C, while [not reduced sediment to] the observed light turbidity. Then the suspension for about 6 h, cooled to a temperature of 15°C and leaked out of the vessel with stirrer. The mother liquor separated from the crystals with suction filter. The output of the solid containing deformat sodium composition was OK. 280, After drying in a vacuum drying Cabinet at a temperature of 35°C the residual water content in the product was about to 0.15 wt.% of the total dry mass, equal to 270, the Content of formic acid in the dry product was 40.1 wt.% of the total dry mass.

Reference example I.3 (analogously to example 2 of German patent DE 424017)

The molar ratio of components in the underlying crystallization aqueous solution does not correspond to the values that must be set by the method according to the invention.

476 g of an aqueous solution of formic acid with a concentration of 80 wt.% put in a vessel. Stirring, added 524 g of solid sodium formate. For the complete dissolution was heated to 120°C. Then the solution was slowly cooled. Crystallization began with a temperature of about 112°C. the Cooling was continued with a speed of about 0,7 K/min to a temperature of 25°C. the Suspension is left (going slightly stir for 24 hours and Then separated the formed crystals from the mother liquor. The output of the wet product was OK. 370, Containing the s formic acid was OK. 21.8 wt.% of the total wet weight of the product.

II. The receipt contains deformat sodium composition with the return of the mother liquor

Test case II.1 (flows according to European patent EP 0824511 B1).

Link to the accompanying figure 1, which gives a schematic representation of a variant of the method according to European patent EP 0824511 B1, wherein the mother solution after the neutralization of the return on the stage of crystallization. 1 mainly corresponds to figure 2 from the publication EP 0824511 B1, but the latter is not shown all of the thread (7a).

In the following tables 1A and 1b as an example, given the balance of flows of substances, which can be based are presented in the publication EP 0824511 B1 data management flow according to figure 2. European patent EP 0824511 B1. The stream (1) submit a solution of formic acid with a concentration of 85 wt.%, and as a flow (6) aqueous sodium hydroxide solution with a concentration of 50 wt.%, as the thread (10) on the stage of crystallization (crystallization) return a solution of sodium formate with a concentration of 80 wt.%.

In this connection it is necessary to specifically point to the fact that from the publication of the European patent EP 0824511 B1, except as provided above flows of substances that cannot be obtained any other specific data about the selected flows of substances. In castnet is, the molar ratio of formic acid and sodium formate specified in the examples presented here II.1 and II.2 in the underlying crystallization stream (2), does not correspond to molar ratios specified according to the patent EP 0824511 B1 as the preferred; it asked respectively to the limits that must be observed in the method according to the invention, since only in this case it is possible to ensure the availability of deformity sodium if possible pure form in the output stream (4).

In tables 1A and 1b through NaFo·AS (s) denoted by the solid deformat sodium through NaFo - sodium formate, formic acid as the water is designated as H₂O, sodium hydroxide through NaOH; the numbers 1 to 10 in the first row of each table indicate the flow indicated in figure 1 by the corresponding number; "the Solution wt.%" means the weight proportions of the components in the respective liquid flow (i.e. without a share solids), "Solution mol.%" the corresponding molar fraction.

The balance calculation above shows that the weight ratio of components in the streams (1) and (10), used here, can be set only if the output is a significant share, namely more than 50 wt.%, solution of sodium formate obtained at the stage of neutralization in the form of a stream (7a). In addition, when connecting threads (1) and (10) results in the stream (2), characterized by a water content of Bo is her 16 wt.% and respectively having a crystallization temperature below 20°C.

Test case II.2 (similar to European patent EP 0824511 B1)

In the control example II.2 also link to the accompanying figure 1. The stream (1) submit a solution of formic acid with a concentration of 94 wt.%, and as a flow (6) aqueous sodium hydroxide solution with a concentration of 50 wt.%, as the thread (10) on the stage of crystallization (crystallization) return a solution of sodium formate with a concentration of 80 wt.%. In other respects are similar to reference example 1. The following tables 2A and 2b displays the calculated flow balance of substances.

The balance calculation above shows that the weight ratio of components in the streams (1) and (10), used here, can be set only if the output is a significant share, namely more than 46 wt.%, solution of sodium formate obtained at the stage of neutralization in the form of a stream(7a).

Example II.1

Link to the accompanying figure 2, which gives a schematic representation of a variant of the method according to the invention, in which the mother liquor is separated into two partial flow (5A) and (5b). Thread (5A) return to the stage of crystallization of the bar is dstone, and the thread (5b) - only after complete neutralization of the thread (6).

The following tables 3A and 3b displays the calculated flow balance of substances. As flow (1) submit a solution of formic acid with a concentration of 94 wt.%, and as a flow (6) aqueous sodium hydroxide solution with a concentration of 50 wt.%. Separation of flow (5) of the partial flows (5A) and (5b) being carried out so that the weight ratio of flow (5A) and flow (5b) was OK. the 2.4:1 and the molar ratio of formic acid in the stream (5b) and the total number of diformate and sodium formate in the stream (4) was 1:1. At the same time as thread (10) on the stage of crystallization (crystallization) return a solution of sodium formate with a concentration of 85 wt.%.

The calculation of the above balance sheet shows that used here, the division of flow (5) of the threads (5a) and (5b) leads to the fact that at the stage of neutralization is not formed, the excess sodium formate, so that the possible removal using thread (7a) can be avoided.

Example II.2

Link to the accompanying figure 3, which gives a schematic representation of a variant of the method according to the invention, in which the mother liquor is separated into two partial flow (5a) and (5b). Thread (5a) return (first) stage of crystallization. Flow (5b) is completely neutralized by a thread (6) and evaporated. The resulting stream (10)containing sodium formate, crystallized (at the second stage of crystallization); resulting liquid phase serves as a stream (13) together with the stream (7) on the stage of evaporation, containing sodium formate solid phase serves as a stream (14) together with the flows (1) and (5a) to (first) stage of crystallization.

The following tables 4A and 4b displays the calculated flow balance of substances. As flow (1) submit a solution of formic acid with a concentration of 94 wt.%, and as a flow (6) aqueous sodium hydroxide solution with a concentration of 50 wt.%. Separation of flow (5) of the partial flows (5A) and (5b) being carried out so that the weight ratio of flow (5A) and flow (5b) was about 2:1 and the molar ratio of formic acid in the stream (5b) and the total number of diformate and sodium formate in the stream (4) was 1:1. While sodium formate return to (first) stage of crystallization in the form of a stream (14), mainly as a solid with a small amount of residual moisture.

The calculation of the above balance sheet shows that used here, the division of flow (5) of the threads (5A) and (5b) leads to the fact that at the stage of neutralization is not formed, the excess sodium formate, so that the possible removal can be avoided. In addition, the water content in comprising sodium formate thread (14)that is returned to the first stage of crystallization, it is possible to reach very small values.

1. A method of obtaining a solid containing deformat sodium composition containing formic acid of at least 35 wt.% from the total mass containing deformat sodium composition in which
a) ensure the flow of formic acid content of formic acid is not less than 74 wt.%;
b) the flow of formic acid phase is) along with containing formate sodium flows from step f) and step (h) is served on the stage of crystallization, where get at an elevated temperature an aqueous solution with a molar ratio of HCOOH:Na[HCOO] more than 1.5:1 and the molar ratio of HCOOH:N₂Oh, constituting at least a 1.1:1;
c) at the stage of crystallization carry out the crystallization of the aqueous solution from step b) to produce a stream containing solids and mother liquor;
d) the resulting stream from step (C) serves on the phase separation, in which the solid phase is separated from the mother liquor, and get the stream containing deformat sodium, and a stream containing mother liquor;
e) divide the stream containing mother liquor from step (d)into two parts;
f) one part of the flow from step e) in a proportion (A) return to step (b);
g) another part of the flow from step e) as share (In) together with a stream that includes a base containing sodium, serves on the stage of neutralization, thus obtaining a mixture containing sodium formate, and the share of the mother liquor (a) and (b) complement each other to 100 wt.%, and the mass ratio of the share of (A) the mother liquor to share (In) is in the range from 20:1 to 1:10; and
h) served from step g) and not necessarily from step h), the mixture containing the sodium formiate, if necessary after removal of its parts, in the form of a stream on the stage of concentration, which remove part of the water contained in this thread, and after separation of the water receiving stream containing fo the MIAT sodium, which directly returns to step b) or crystallized in the second stage, crystallization and separation, and the resulting liquid phase serves as a stream on the stage of concentration (h)and solid phase serves as a stream in step b).

2. The method according to claim 1, and obtaining an aqueous solution is carried out at a temperature not lower than 100°C.

3. The method according to claim 1, and the ratio of part a to part (B) the mother liquor can be set so that the molar ratio of HCOOH in part (B) the mother liquor to the total number of substances diformate sodium and possibly formate sodium contained in the solid phase, prior to the drying of the solid phase, which, if necessary, carry out afterwards, was not more than 1.2:1.

4. The method according to claim 1, and a base containing sodium, choose in step (g) from the group consisting of sodium hydroxide, sodium carbonate, sodium bicarbonate, alkanoate sodium with 1-6 carbon atoms, and mixtures thereof.

5. The method according to claim 1, and in step (g) is basically completely neutralize share (In) the mother liquor.

6. The method according to claim 1, and in step (h) take no more than 20 wt.% containing sodium formate mixture by weight of the total mixture, containing sodium formate.

7. The method according to claim 1, and a part containing sodium formate mixture obtained in step (g), is selected and output, and the amount of sodium formate, the content is ameesha in the remaining part of the mixture, with the amount of sodium formate contained in part (A) the mother liquor, gives the total amount of sodium formiate used to obtain an aqueous solution.

8. The method according to claim 1, whereby the water content of a mixture containing sodium formate, from step (h) until her return to the stage b) is reduced to a value of not more than 20 wt.% from the total mass of the mixture.

9. The method of claim 8, and reducing the water content achieved through phase evaporation or by using the second stage of crystallization, which receive the second solid phase and a second mother liquor, and the second stage of concentration, in which the second solid phase is separated from the second mother liquor.

10. The method according to claim 1, and in step d) a stream containing mother liquor mainly contains formic acid concentration in the range from 35 to 80 wt.%, formate sodium concentration in the range from 20 to 45 wt.%, and the water content is in the range from 0 to 30 wt.%, in each case on the total weight of the stream.

11. The method according to claim 1, and in step g) as a stream that includes a base containing sodium, using aqueous sodium hydroxide solution with a content of NaOH in the range from 10 to 60 wt.% from the total mass of the aqueous solution of caustic soda.

12. The method according to claim 1, and a stream containing sodium formate from step (h)contains mostly sodium formate with conc what Tracia in the range from 50 to 100 wt.% and water, the content of which ranges from 0 to 50 wt.%, in each case on the total weight of the stream.

13. The method according to claim 1, wherein the stream containing sodium formate from step h), crystallized in the second stage, crystallization and separation, and the resulting liquid phase serves as a stream on the stage of concentration (h)and solid phase serves as a stream in step b).

14. The method according to item 13, and the flow of the liquid phase comprising the mother liquor contains mostly water, with a share ranging from 20 to 50 wt.% and formate sodium concentration in the range from 50 to 80 wt.%, in each case on the total weight of the stream.

15. The method according to item 13, and a stream containing the solid phase contains mainly sodium formate concentration in the range from 75 to 100 wt.% and the water content in the range from 0 to 25 wt.%, in each case on the total weight of the stream.

16. The method according to claim 1, and a solid containing deformat sodium composition is characterized by the content of formic acid in the range from 38 to 41 wt.% from the total mass containing deformat sodium composition.