The method of producing pentaerythritol

 

(57) Abstract:

Use: in the manufacture of explosives. The inventive product: pentaerythritol, BF C5H12O4yield 85%; so pl. 256 - 258°C; the content of dipentaerythritol of 0.3%, sugary substances is 0.003. Formate, calcium, BF C2H20O4Ca exit 36 kg ha1 mol of acetaldehyde. Reagent 1: acetaldehyde. Reagent 2: formaldehyde. Reaction conditions: in an aqueous medium in the presence of calcium oxide, 0.67 mol lime milk is added to the reaction mass, containing 72 mol of water, 5.5 mol of formaldehyde and 1 mol of acetaldehyde, then condensing the solution is heated until complete conversion of aldehydes and neutralize 0,346 - 0,423 mol H2SO41 mol of acetaldehyde, produce pentaerythritol and then formate calcium. table 1.

The invention relates to organic chemistry, namely to improve the method of producing pentaerythritol (PE), used in the manufacture of explosives, the simultaneous achievement of calcium formate used in the pulp and paper, leather industries, construction and agriculture.

Closest to the proposed method is to obtain PE poluchenii while the reaction mixture with sulfuric acid, treatment of the neutralized mass of the inorganic salt of sodium. Neutralization of the reaction mixture with sulfuric acid leads to pH 5-5,5 and as inorganic sodium salt using sodium sulfate.

The disadvantages of this method lies in the fact that extend the time of condensation due to the supply of acetaldehyde up to 1 h, the presence of sodium ash excludes the application of pentaerythritol for special purposes, the quality of the obtained pentaerythritol not meet state standards 9286-89. This method cannot simultaneously with pentaerythritol to get calcium formate, as it completely breaks down to gypsum and formic acid at the stage of neutralization of the reaction mixture with sulfuric acid.

If the partial demolition of the calcium formate to the content of 1.3 wt.%, in terms of Cao, it leads to deterioration of the quality of PE, i.e., to increase the content of dipentaerythritol that makes it impossible to use PE for special purposes.

The purpose of the invention is the obtaining of PE of high quality, suitable for special purposes with the possibility of obtaining calcium formate.

This goal is achieved by adding 0.67 mol of lime milk to the reaction mass, containing 72 mol vacuumin heating of the condensation solution and neutralizing the reaction mass is based 0,346-0,423 mol H2SO41 mol of acetaldehyde, the selection of PH and calcium formate.

To increase the output of calcium formate in the allocation of the mother liquor before the residue is neutralized with lime milk. PE, is obtained in this way corresponds to the Marche B, suitable for special purposes, and you can highlight formate calcium in the form of crystals by evaporation.

The proposed method is as follows.

P R I m e R 1. In the reactor when operating the mixer load 2708 l of cold water, 1579 kg chilled formalin (formaldehyde content of 36.7 wt. %) and 154 kg of acetaldehyde. When the temperature of the 13aboutTo download 958 kg of milk of lime with a Cao content of 13.7 wt.%.

The condensation solution is heated at 50about12-13 min) until complete disappearance of the aldehyde.

The content of sugary substances and Cao in the solution after complete disappearance of the aldehyde is 1.3 and 0.7 wt.% respectively. After that the reaction mixture is kept for 15 min at 73aboutSince, however, the contents of sugary substances in the solution is reduced to 0.3, and Cao - up to 0.1 wt.%. The reaction mass is neutralized and partly precipitated calcium ions 176 kg of sulfuric acid (concentrabamos and subsequent centrifugation receive technical pentaerythritol.

After recrystallization of technical pentaerythritol with activated carbon from hot water to obtain the target product with the following quality indicators: I. pl.,aboutWITH 256-258

The content of Sakha - ristich substances, wt.% 0.003

The content of depen - fericita, wt.% 0.3 Yield, mol% 85

The mother liquor in the amount of 1,600 kg, obtained after separation of technical PE, has the following composition, wt.%: Formate calcium 11,4 Formic acid 2,3 Sweeteners 1.2 Pentaerythritol 6,2

This solution is neutralized 235 kg of milk of lime with a Cao content of 13.7 wt. %. Neutralized mother liquor has the following composition, kg: calcium Formate 234 Sugary substances 19 Pentaerythritol 98 Water 1472 total 1835

From neutralized mother liquor at 80aboutWith vacuum distilled 1100 kg of water, and the precipitated calcium formate centrifuged at 80aboutWith, dried, yielding 126 kg of calcium formate.

The mother liquor after separation of calcium formate in the amount of 600 kg has the following composition, wt.%: Formate calcium 16,0 Sweeteners 3.2 Pentaerythritol 16,3

The mother liquor after separation of the calcium formate is cooled to 25aboutWith and additionally allocate technical PE (60 kg).

The results are shown in the table.

The process proposed method allows you to:

get another product - formate, calcium, used as a coagulant in the pulp and paper industry, for pre-tanning in the tanning industry, as additives in concrete and as a preservative of food;

to increase the output of PE due to vicalvaro effect of calcium formate;

reduce the formation of PE with an instantaneous supply of acetaldehyde, which leads to an increase in the allocation of menopa;

reduced emissions of formic acid in 2-3 times.

The mother liquor after separation of calcium formate and an additional quantity of PE may be used as film-forming composition for coating bulk cargo.

The gypsum obtained by partial cooling of calcium ions, is used as a building material.

PE, is obtained in this way corresponds to GOST 9286-89 on PE designed for special purposes.

The METHOD of producing PENTAERYTHRITOL condensation of formaldehyde with acetaldehyde in an aqueous medium in the presence of calcium oxide to complete the conversion of aldehydes with after the I, what, with the aim of obtaining pentaerythritol high quality, suitable for spenceley and the possibility of obtaining calcium formate, to 0.67 moles of lime milk is added to the reaction mass, containing 72 mole of water, 5.5 moles of formaldehyde and 1 mol of acetaldehyde, the neutralization is carried out with sulfuric acid in the amount of 0,346 - 0,423 mol per 1 mol of acetaldehyde, followed by separation of pentaerythritol, and then formate calcium.

 

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SUBSTANCE: proposed method includes concentration of pentaerythrite formate mother liquors at the first stage by evaporation to saturation state by pentaerythrite and crystallization of pentaerythrite from saturated solution; concentration at the first stage is performed at film flow solution; crystallization is carried out at two stages at forced circulation of suspension thus formed. Secondary vapor is divided into two flows after first stage of evaporation: one flow is delivered to the first stage of crystallization and second flow is delivered to the second stage of crystallization. At the second stage of crystallization boiling point of suspension is maintained at temperature of 45-53°C which is below that at the first stage by 7-20°C. Evaporation plant for processing the pentaerythrite formate mother liquors has two stages of evaporators connected in succession in way of flow of vapor and solution and provided with vertical tubes. Second stage of evaporation plant is just crystallizer provided with circulating loop with pump and vapor separator connected with final condenser by means of vapor pipe line. First stage consists of film liquid flow evaporator; second stage is provided with additional crystallizer with circulating loop and pump and additional condenser connected with vapor separator of additional crystallizer; it is also provided with non-condensable gas discharge unit. Last evaporator of the first stage is provided with additional pipe line for discharge of secondary vapor which is communicated with heating chamber of additional crystallizer. Solution volume of additional crystallizer exceeds that of the first one by 1.5- 2.5 times.

EFFECT: improved quality of crystalline products; increased degree of extraction of pentaerythrite from solution; increased rate of processing the solutions.

6 cl, 1 dwg, 1 tbl

FIELD: chemistry.

SUBSTANCE: present invention relates to a method for synthesis of pentaerythritol and dipentaerythritol, involving reaction of acetaldehyde with formaldehyde in the presence of sodium hydroxide, purification of the reaction solution through distillation of excess formaldehyde, evaporation and crystallisation of technical pentaerythritol, washing the residue, recrystallisation of technical pentaerythritol, separation of the residue from the solution and drying commercial-grade pentaerythritol and treatment of the product after drying. After drying the product is treated through separation, thereby extracting the pentaerythritol fractions most contaminated with non-volatile impurities of dipentaerythritol and cyclic formalin, and the extracted fractions are processed by leaching pentaerythritol with demineralised water at 10-80°C and ratio of liquid phase to solid phase equal to (5.5-8)/1, and subsequent separation of the formed pentaerythritol solution and dipentaerythritol precipitate and taking the pentaerythritol solution to the technical pentaerythritol recrystallisation step.

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6 cl, 1 tbl, 7 ex

FIELD: chemistry.

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2 tbl, 1 ex

FIELD: process engineering.

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2 cl, 1 tbl, 1 ex

FIELD: chemistry.

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EFFECT: method increases efficiency of the process while ensuring high quality of the ready product.

1 ex

FIELD: chemistry.

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EFFECT: high effectiveness of the process while ensuring the required quality of the product.

1 tbl, 1 ex

FIELD: chemistry.

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EFFECT: method reduces losses in output of polymethylol.

12 cl, 5 ex

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,

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14 cl, 4 ex

FIELD: chemistry.

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3 cl, 4 ex

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1 cl, 3 tbl, 3 ex

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3 cl, 4 tbl, 4 ex

FIELD: chemical industry; methods of production of the ferric formiate (III).

SUBSTANCE: the invention is pertaining to the field of chemical industry, in particular, to the method of production of the ferric formiate (III). The invention is dealt with the organic salts of the transition metals, in particular to production of the salt of the ferric iron and the formic acid. The method is realized by the direct interaction of the regenerated iron powder with the formic acid at presence of the molecular iodine and oxygen of the air as the oxidizing agents. The process is running in the medium of dimethylformamide as the dissolvent for preparation of the necessary liquid phase with the concentrations of the formic acid and iodine of 4.5-10 and 0.03-0.11 mole/kg accordingly. The mass ratio of the liquid phase and the powder of the regenerated iron is 3:1. The process starts at the room temperature and is conducted in the conditions of the forced cooling at the temperature of 50-80°С at the rate of the air consumption for the bubbling of 0.6-1.2 l\minute per 1 kg of the liquid phase. The process is terminated at accumulation of the ferric formiate (III) in the suspension up to 1-1.2 mole/kg. The suspension is separated from the particles of the non-reacted iron and then filtered. The filtrate is recycled to the repeated process, and the ferric formiate (III) (salt) is dried and either is used as required, or additionally is purified by the recrystallization. The technical result of the invention is simplification of the method with improvement of the economic indicators and the increased purity of the final product.

EFFECT: the invention ensures simplification of the method with improvement of the economic indicators and the increased purity of the final product.

8 ex

FIELD: production of salts of organic acids, salt of ferrous iron and formic acid in particular.

SUBSTANCE: proposed method consists in loading preliminarily prepared aqueous solution of formic acid at concentration of 4.5-10 mole/kg into reactor provided with bladed mixer, back-flow condenser-cooler and air bubbler. Then, powder of reduced iron and/or broken iron and/or steel chips at any mass ratio in total amount of 20.0-30.6% of mass of liquid phase and stimulating iodine additive in the amount of 0.016-0.164 mole/kg of liquid phase are introduced. Reactor may be provided with steel or cast iron ferrule over entire height. At mechanical mixing, consumption of air for bubbling is maintained between 1.2 and 2.0 l/(min·kg of liquid phase). Working temperature range is 45-65°C which is maintained by external cooling. Process is discontinued when content of iron salts (II) in reaction mixture reaches 1.8-2.0 mole/kg. Suspension of salt in liquid phase is separated from unreacted iron particles and is filtered afterwards. Filtrate is directed for repeated process and salt sediment is re-crystallized from aqueous solution saturated with iron formate by formic acid at concentration of 1-2 mole/kg at heating to temperature of 95°C followed by natural cooling.

EFFECT: enhanced efficiency.

1 tbl, 9 ex

FIELD: chemical industry; methods of production of the salts of iron and the organic acids.

SUBSTANCE: the invention is pertaining to the field of chemical industry, in particular, to the method of production of the salts of the metals of the organic acids, in particular, to production of the salt of the ferrous iron and the formic acid. The method is realized by the direct interaction of the formic acid water solution with the iron and/or its alloys and the ferric oxidesFe2O3 and Fe3O4 in the bead crumber of the vertical type along the whole its height with the steel shell, with the heat supply and equipped with the mechanical stirrer and the backflow condenser-refrigerator. The apparatus is loaded with 23-46 % water solution of the formic acid as the liquid phase in the mass ratio with the glass beads as 1:1.25 and then introduce the oxide - Fe3O4 orFe2O3 in amount of 0.27-0.49 or 0.48-0.64 mole/kg of the liquid phase accordingly, and besides in amount of 18 % from the mass of the liquid phase they add the powder of the reduced iron and-or the crushed cast iron, and-or the crushed steel chips in any mass ratios. Switch on the mechanical stirring and heating and keep the temperature in the reaction zone within the limits of 55-75°С. The process is terminated, when practically the whole loaded oxide is completely consumed. The suspension of the salt is separated from the non-reacted iron, its alloy and the beads and dilute with the water up to the contents of the formic acid within the limits of 1-2 mole/kg. The gained mass at stirring action is slowly heated up to temperature of 85-95°С, controlling transformation of the solid phase into the solution. The gained solution is subjected to the hot filtration, evaporation, cooling and separation of the salt crystals. The filtrate and the earlier the gained distillate are sent back to the repeated process. The technical result of the invention is simplification of the technology of the production process with utilization of the accessible raw.

EFFECT: the invention ensures simplification of the technology of the production process with utilization of the accessible raw.

10 ex

FIELD: chemical industry; methods of production of the salts of iron and the organic acids.

SUBSTANCE: the invention is pertaining to the field of chemical industry, in particular, to the method of production of the salts of iron and the organic acids, in particular, to production of the salt of the ferrous iron and the formic acid. The method is realized by the direct interaction of the acid with the iron, its alloys and the ferric oxides. The crumber with the beads and the backflow condenser is loaded with the organic solvent, the formic acid and the water in the mass ratio of 100:(85÷100): (15÷0). As the organic solvent they use ethylcellosolve, butyl acetate, butyl and amyl alcohols, ethylene glycol. The mass ratio of the beads and the liquid phase is 1:1. Ferric oxideFe2O3 orFe3O4 and the iodine are loaded in the amount of 0.40-0.56 or 0/21-0.42 and 0.03-0.1 mole/kg of the liquid phase accordingly. The iron is introduced in the form of the steel shell along the whole height of the reactor and additionally in form of the reduced iron, the fractions of the broken cast iron with dimensions of up to 5 mm and the steel chips in any ratio among themselves at total amount of 20 % from the mass of the liquid phase. The process is conducted at the temperature of 35-55°С practically till the complete consumption of the ferric oxide. The gained suspension is separated from the beads and the metal particles of the greater dimensions and subjected to centrifuging or sedimentation. The clarified liquid phase is returned to the repeated process, and the solid phase is dissolved at stirring action and warming up to 85-95°С in the water solution of the formic acid saturated by the ferric formiate (II) up to 1-2 mole/kg. The present solid impurities are removed at the hot filtration process and the filtrate is cooled and the salt crystals are separated. The technical result of the invention is simplification of the technology of the production process with utilization of the accessible raw.

EFFECT: the invention ensures simplification of the technology of the production process with utilization of the accessible raw.

3 cl, 17 ex

FIELD: inorganic synthesis.

SUBSTANCE: invention relates to preparation of salts of transition metals with organic acids, in particular to formic acid ferric salt. Method is accomplished in bead mill provided with mechanical blade-type stirrer in aqueous formic acid solution (5-10 mole/kg). Iron is used in the form of steel sidewall across the height of reactor and also as particles of reduced iron stirred with stirrer together with glass beads, and/or as broken steel cuttings, and/or yet as split cast iron in any weight proportions. Method is accomplished by continuously introducing 10-20% hydrogen peroxide solution at a rate of 0.015-0,030 mole peroxide/min per 1 kg liquid phase (salt slurry) in presence of stimulating additive, in particular iodine, bromine, alkali metal or ferrous iodides or bromides in amounts (on conversion to halogens) 0.1-0.15 vole per 1 kg reaction mixture. When 1,2-1,5 mole/kg of ferrous salt is accumulated in reaction mixture, stirring and addition of hydrogen peroxide solution are stopped, product slurry is separated from unreacted iron and/or its alloys as well as from glass beads and filtered. Filtrate is recycled into process and precipitate is recrystallized from saturated iron formate solution of aqueous formic acid solution (1-2 mole/kg).

EFFECT: simplified finished product isolation stage, reduced total process time, and reduced power consumption.

1 tbl, 11 ex

FIELD: inorganic synthesis.

SUBSTANCE: invention relates to preparation of salts of transition metals with organic acids, in particular to formic acid ferric salt. Method is accomplished via oxidation of ferrous formate with hydrogen peroxide in presence of formic acid and in absence of any dorm of iron as reducer in order to prevent reduction of ferric salt into original ferrous salt. As reducer, ferrous formate is used preliminarily recrystallized and dried or filtered off from reaction mixture suspension. Process is carried out in upright bead mill in two steps. In the first step, ferrous formate powder or precipitate is combined, stepwise or in one go, with 85% formic acid or mixture of filtrate with wash water formed during isolation of desired product to form pasty slurry ensuring stable functioning of bead mill. Second-step operation is effected in bead mill functioning mode involving forced cooling through side surfaces of reactor and continuous introduction of 12.5-25% hydrogen peroxide solution at a rate of 3.25-4.24 g H2O2 per 1 kg starting charge until degree of Fe(II) salt conversion achieves 85-90%. Supply velocity is then lowered until complete conversion is reached. Resulting product slurry is separated from beads and filtered. Filter cake is washed with 85% formic acid and recrystallized in saturated ferric formate solution containing 20-30% of formic acid. Wash liquid is combined with filtrate and used in the first step as described above.

EFFECT: increased yield of target product and simplified its isolation step.

1 tbl, 8 ex

FIELD: concentration of pentaerythrite formate mother liquors in the multi-case evaporation plant with vertical heat exchange tubes for production of high-quality lacquers, additives for oils and other products.

SUBSTANCE: proposed method includes concentration of pentaerythrite formate mother liquors at the first stage by evaporation to saturation state by pentaerythrite and crystallization of pentaerythrite from saturated solution; concentration at the first stage is performed at film flow solution; crystallization is carried out at two stages at forced circulation of suspension thus formed. Secondary vapor is divided into two flows after first stage of evaporation: one flow is delivered to the first stage of crystallization and second flow is delivered to the second stage of crystallization. At the second stage of crystallization boiling point of suspension is maintained at temperature of 45-53°C which is below that at the first stage by 7-20°C. Evaporation plant for processing the pentaerythrite formate mother liquors has two stages of evaporators connected in succession in way of flow of vapor and solution and provided with vertical tubes. Second stage of evaporation plant is just crystallizer provided with circulating loop with pump and vapor separator connected with final condenser by means of vapor pipe line. First stage consists of film liquid flow evaporator; second stage is provided with additional crystallizer with circulating loop and pump and additional condenser connected with vapor separator of additional crystallizer; it is also provided with non-condensable gas discharge unit. Last evaporator of the first stage is provided with additional pipe line for discharge of secondary vapor which is communicated with heating chamber of additional crystallizer. Solution volume of additional crystallizer exceeds that of the first one by 1.5- 2.5 times.

EFFECT: improved quality of crystalline products; increased degree of extraction of pentaerythrite from solution; increased rate of processing the solutions.

6 cl, 1 dwg, 1 tbl

FIELD: chemical industry; methods of production of the manganese salts with the organic acids.

SUBSTANCE: the invention is pertaining to production of the manganese salts with the organic acids in particular, to the salt of the divalent manganese and formic acid. The method is exercised by interaction of manganese, its oxides in the state of the highest valence with the formic acid solution in the organic solvent in the presence of iodine as the stimulating additive. The production process is conducted in the bead grinder of the vertical type having the revertive cooler-condenser, the high-speed paddle stirrer and the glass beads of in the capacity of the grinding agent loaded in the mass ratio to the loading of the liquid phase as (1÷2): 1. The liquid phase consists of the formic acid solution in the organic solvent. The concentration of the acid is taken within the range of 3.5÷10.8 mole/kg. In the loaded liquid phase they dissolve the stimulating additive of iodine in the amount of 0.025-0.100 mole/kg of the liquid phase. The ratio of the masses of the liquid phase and the total of the metallic manganese and the manganese oxide are as(4.9÷11):1. The molar ratio of the metal and the oxide in the loading is as (1.8÷2.,2):1. The metal and the oxide are loaded the last. It is preferable in the capacity of the dissolvent to use the butyl alcohol, ethyl acetate, ethylene glycol, 1.4-dioxane, dimethyl formamide. The production process is started and conducted at the indoor temperature up to practically complete(consumption of the whole loaded manganese oxide. Then the stirring is stopped, the suspension of the salt is separated from the beads and the nonreacted manganese and after that conduct filtration. The filtrate and the nonreacted manganese are returned into the repeated production process, and the filtered out settling of the manganese salt is exposed to purification by recrystallization. The technical result of the invention is - simplification of the method at usage of accessible reactants.

EFFECT: the invention ensures simplification of the method at usage of accessible reactants.

16 ex, 2 tbl

FIELD: chemistry.

SUBSTANCE: preparation of liquid flow I, containing formic acid, and liquid flow II, containing alkali metal formate, is carried out; liquid flows I and II are supplied to rectification column in such way that for liquid flow II place for feeding into rectifying column is chosen higher than place of feeding liquid flow I, or the same place as for liquid flow I, liquid flows I and II are mixed in rectification column, removing water from upper part of rectification column, and lower flow, containing formic acid formate is removed from rectification column, lower flow being separated in form of melt, which contains less than 0.5 wt % of water.

EFFECT: improved method of production of formic acid formates.

10 cl, 4 ex

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