The way to obtain calcium formate

 

(57) Abstract:

Usage: salts of carboxylic acids, forminal of calcium from formaldehyde. The inventive lead reaction of aqueous formaldehyde with calcium hydroxide at 60 - 70oIn the presence of boric acid or borax. The mass ratio of calcium hydroxide and acid 1 : 0.03 or borax 1 : 0,09. The process is continued until the complete exhaustion of formaldehyde. Preferably as calcium hydroxide to use metallurgical lime in the form of lime milk. 1 C. p. F.-ly, 1 table.

The invention relates to salts of carboxylic acids, in particular a process for the production of calcium formate used in cellulosome and leather industry, construction and agriculture.

A method of obtaining calcium formate by condensation of formaldehyde with acetaldehyde in the presence of calcium oxide to complete the conversion of aldehydes and subsequent heating of the condensation solution and neutralizing the reaction mixture with sulfuric acid.

However, in this method, the calcium formate is not in pure form, but mixed with pentaerythritol, which impairs specifications when using it.

shimodate 4-11,5% aqueous solution of formaldehyde with calcium hydroxide in dilute aqueous solutions at 40-70aboutIn the presence of a metal salt. As a source of calcium hydroxide use of building lime. The process is carried out at a mass ratio of Ca(OH)2and salts of 1:(of 0.004 to 0.15).

However, in this way the process is conducted not before full actuation of formaldehyde in the case of the selection of the finished product it is necessary to drive away the remaining formaldehyde, which increases the power consumption, in addition, the presence of impurities in the construction of lime affects the quality of the finished product, and selected additives degrade the color of the finished product, slow reaction time, increase its solubility in the mother solution, which reduces its output.

The aim of the invention is the simultaneous production and secretion of calcium formate to the specifications of the relevant international standards, increasing the selectivity of the conversion of formaldehyde to formate and increasing the yield of the finished product.

The objective is achieved by conducting the process at a temperature of 60-70aboutWith up to full actuation of formaldehyde in the presence of boric acid or its salts, borax when the mass ratio of calcium hydroxide and

boric acid 1:0,03

borax 1:0,09 water restorereplica production in the form of lime milk. Lime is produced by burning conventional or dolomitic limestone in the furnace units using gaseous, liquid or solid fuel if 0 or if 1 OST 14-16-165-85.

P R I m e R 1. In the reactor when operating the mixer load 1549 kg of formalin (concentration 36,8%), 2710 l of water and 21 kg of boric acid. Mix for 3-5 minutes Download 1166 kg of milk of lime with the content of Ca(OH)223.8% and continue to mix. The ratio of Ca(OH)2H3BO31:0,09. The solution thermostatic at a temperature of 60aboutWith the disappearance of the aldehyde. The end of the reaction is controlled by the indicator phloroglucin. Duration of response 40 minutes the Reaction mass naturalizirujut 30 kg of sulfuric acid (concentration of 75% ) to pH 5.5. Gypsum is separated, the resulting filtrate contains 11.4% of calcium formate. From the filtrate by evaporation under vacuum and subsequent centrifugation get the finished product of calcium formate in the amount of 530 kg of the quality of the finished product at the level of world standards. Conversion of formaldehyde 100% selectivity of the formation of formate calcium 100%

P R I m m e R 2. The process is carried out analogously to example 1, but instead of boric acid is used Bura Na2B4O7< to the disappearance of the aldehyde. The duration of reaction 30 minutes the Reaction mass is neutralized 20 l of sulfuric acid to pH 6.5. Gypsum is separated. The resulting filtrate contains 11.4% of calcium formate. From the filtrate by evaporation under vacuum and subsequent centrifugation get the finished product formate calcium in the amount of 530 kg of the quality of the finished product meets the requirements of world standards. The selectivity of the formation of formate calcium 100% conversion of formaldehyde 100%

P R I m e R 3. The process is carried out analogously to example 1, but the ratio of Ca(OH)2H3BO31: 0,1. The solution thermostatic at a higher temperature 70aboutC. Duration of response 60 minutes the resulting solution contains 1.0% formaldehyde and 10.3% of calcium formate. The selectivity of the formation of formate calcium 90,3% conversion of formaldehyde 90%

P R I m e R 4. The process is carried out analogously to example 1, but the ratio of Ca(OH)2Na2B4O71:0,04. The solution thermostatic at a temperature of 70aboutC. Duration of response 60 minutes the resulting solution contains 0.9% formaldehyde and 10.4% of calcium formate 91% conversion of formaldehyde 91%

P R I m e R 5. The process is carried out analogously to example 1, but the ratio of Ca(OH)2: H3BO31:0,08. The solution covers a lot neutralize 30 kg of sulfuric acid to pH 5.5. Gypsum is separated. The resulting solution contains 10.3% of calcium formate and 1.0% sugary substances. From the filtrate by evaporation under vacuum and further centrifugation get the finished product formate calcium content of the basic substance about 90% selectivity of the formation of formate calcium 90,4% conversion of formaldehyde 90,5%

P R I m e R 6. The process is carried out analogously to example 1. But the ratio of Ca(OH)2Na2B4O71:0,02. The solution thermostatic at a temperature of 50aboutWith the disappearance of the aldehyde. Duration of response 20 minutes, the Reaction mass is neutralized 20 l H2SO4to pH 6.5. Gypsum is separated. The resulting filtrate contains 0,9% sugary substances, 10.4% of calcium formate with a basic substance content of about 90% selectivity of the formation of formate calcium 91,3, the conversion of formaldehyde to 91.4%

The results of the experiments are shown in the table.

Carrying out the processes of the proposed method allows to obtain calcium formate, corresponding to the international standards, when using the improving quality of the products in cellulosome and leather industry, construction and agriculture.

1. The METHOD of producing FORMATE CALCIUM interaction characterized in that the process is continued until complete conversion of formaldehyde and as an additive use boric acid or borax in the mass ratio of calcium hydroxide and acid 1 : 0.03 or borax 1 : 0,09.

2. The method according to p. 1, characterized in that the calcium hydroxide is used in metallurgical lime Ferroalloy production with the content of calcium oxide 93 - 95% in the form of lime milk.

 

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7 tbl, 3 ex

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3 cl, 4 tbl, 4 ex

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8 ex

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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

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