Method of processing filtrate wastes from pentaerythritol production

FIELD: chemistry.

SUBSTANCE: present invention relates to a method of processing filtrate wastes from production of pentaerythritol, containing (wt %): 32-37.81 sodium formate, 22-27 pentaerythritol, 10-11 cyclic monoformals, 2-3 dipentaerythritol, as well as pentaerythritol derivative impurities, to obtain technical pentaerythritol and sodium formate. The method involves treatment of the filtrate with an extraction agent, followed by separation and recycling of the obtained liquid and solid phases. Treatment is carried with water in water/filtrate ration equal to (0.5-1.0)/1 and temperature 15-25°C, followed by taking the washed off residue to the evaporation and crystallisation step to obtain technical pentaerythritol and the filtrate solution for evaporation and crystallisation to obtain sodium formate.

EFFECT: efficient method of processing waste filtrate from production of pentaerythritol.

2 tbl, 1 ex

 

The present invention relates to technology of organic synthesis, namely the joint production of pentaerythritol and sodium formate, in which is formed a waste of filtrate in the form of a syrupy suspension containing sodium formate, pentaerythritol, cyclic nonformal, dipentaerythritol, as well as the impurity derivatives of pentaerythritol.

There is a method of recycling the mother liquor containing the pentaerythritol and sodium formate, by treatment with formalin /1/. This forms a soluble cycloacetal pentaerythritol and sodium formate Myslivets and it is separated by filtration. Next, the filtrate is treated with alkali, linking formaldehyde and destroying cycloacetal, then allocate pentaerythritol by crystallization and filtration. The disadvantage of this method is the use of toxic and expensive reagent - formalin solution.

Also known is a method of processing waste leachate production pentaerythritol /2/, which includes heating the waste leachate fatty acid series when 175-275°C to education "fat" and solid phases, followed by the separation and disposal of "fat" phase containing the fatty acid esters polyoxicompounds. The disadvantage of this method is the high cost of implementation of the method associated with the need of heating the waste filtrate up to 275°C and the use of Dor is gostosa fatty acids.

Also known is a method of processing waste leachate production of pentaerythritol by treating the filtrate with extractants cyclohexane or ethanol /3/, with additional acidification of a solution of mineral acid (nitric, hydrochloric or sulfuric) with subsequent filtering and washing the crystals of pentaerythritol with distilled water. The resulting liquid phase and a suspension of sodium formiate is filtered in the heated indoor filter from dried residue of ethyl alcohol and water, obtaining crystals of sodium formiate. The disadvantages of this method is the high cost of implementation of the method associated with the high cost of extractants and toxicity extractants.

The aim of the invention is the reduction of costs for the implementation of the method and the toxicity of the reagents.

This objective is achieved in that in the method of processing waste leachate production of pentaerythritol containing (wt.%): 32-37,81 of sodium formiate, 22-27 pentaerythritol, 10-11 cyclic nonformula, 2-3 dipentaerythritol, as well as the impurity derivatives of pentaerythritol, including the processing of the filtrate the solvent, followed by separation and disposal of the resulting liquid and solid phases, the treatment is carried out with water at a ratio of water/leachate equal to (0,5-1,0)/1, and temperatures of 15-25°C, with subsequent supply the washed precipitate, a hundred is the I residue and crystallization to obtain technical pentaerythritol, and solution of the filtrate on evaporation and crystallization to obtain sodium formate.

Impurities derivatives of pentaerythritol are formed as a result of the occurrence of side reactions at the stage of synthesis of pentaerythritol. In the composition of impurities included formali of dipentaerythritol various buildings, as well as sugary substances that are formed due to the condensation of formaldehyde in an alkaline environment and are a mixture of various sugars.

Processing waste filtrate water with subsequent disposal of the washed precipitate in the production of pentaerythritol, and mud filtrate in the production of sodium formiate eliminates the introduction of new expensive and toxic reagents in these industries.

The processing of waste leachate at a ratio of water/leachate equal to (0.5÷1.0)/1, allows to obtain a high yield of sediment pentaerythritol. When the ratio of water/filtrate is less than 0.5/1, the separation of the components of the waste leachate by the solubility in water is difficult because of high viscosity and density. In addition, reduced speed mechanical separation of solid and liquid phase by filtration or centrifugation. With the increase in the ratio of water/leachate above 1 reduced the sediment yield of pentaerythritol and dilutes the liquid phase on sodium formate, which is subsequently evaporated, that the Veda is the cost of the recycling method of waste leachate.

Processing waste filtrate water (no hot water) at temperatures of 15-25°C does not require any additional power consumption, which reduces costs for the implementation of the method. At temperatures below 15°C the efficiency of processing water filtrate is reduced due to the increase in the Deposit pentaerythritol impurities of sodium formiate. In addition, in summer conditions, lowering water temperatures below 15°C requires additional cooling costs.

At water temperatures above 25°C processing efficiency water solid phase of the waste filtrate is reduced, as the pentaerythritol has a positive temperature coefficient of solubility with increase in temperature, increased loss of pentaerythritol due to the transition of pentaerythritol in the liquid phase.

Supply the washed precipitate on stage evaporation and crystallization to obtain technical pentaerythritol current production of pentaerythritol allows you to completely dispose of sludge waste filtrate receiving technical pentaerythritol, which will lead to additional production at the facility crystallization.

The supply of the solution of the filtrate on evaporation and crystallization to obtain sodium formate allows you to fully utilize formate sodium contained in the solution, getting additional volume of commodity formate sodium working of the mouth of the plant production of sodium formiate.

Examples of the method

As object of research used the waste filtrate production of pentaerythritol JSC "Metafrax" of the following composition (wt.%): the pentaerythritol - 22,5; formate sodium - 37,81; dipentaerythritol at 2.45; cyclic nonformal to 10.7; impurity derivatives of pentaerythritol. At room temperature it was a viscous suspension, density ~1,457 g/cm3.

Processing took a portion of the waste filtrate, mixed it with different amounts of water, and then placed in a thermostat at a temperature of 20°C and stirred propeller stirrer in the reactor for 30 minutes. After leaching the resulting suspension was separated by filtration at 20°C under vacuum through a double filter paper, measuring the duration of sediment filtration. After that, the precipitate and the solution was weighed, determined the density of the solution and analyzed the content of the main components in the sediment and solution. Sediment composition suitable for mixing with the solution entering the evaporation and crystallization of technical pentaerythritol, i.e. for processing it in technical pentaerythritol. And obtained after processing of the waste filtrate solution composition suitable for feeding to the evaporation and crystallization of sodium formiate, i.e. processing into marketable sodium formate.

The correlation of phases of water/fil the rat, iein experiments 1-6 changed from 0.20 to 1.00. The degree of extraction of each component in the solid and the liquid phase was determined as the ratio of the mass of the component in phase to the weight of this component in the original waste leachate. The results of processing waste leachate different amounts of water are given in tables 1-2.

Table 1
Indices of processing waste filtrate water
No.Indicators for the handling of waste filtrate waterPerformance after treatment of the waste filtrate water
The mass of the original waste filtrate, gThe mass of the H2About to handle, gThe correlation of phasesThe output of the receiving solution, %The density of the resulting solution, g/cm3Duration sediment filtration, minThe sediment yield, %
110020 0,20044.71-55,29
210028,60,28677,851,3123022,15
310033,3of 0.33378,861,2852421,14
4100400,40081,101,2711918,90
5100500,50083,961,2511516,04
675751,00090,641,18214 9,36

4,17
Table 2
The concentration of the components in the solid and liquid phases after treatment of the waste filtrate water
No.23456
The correlation of phases0,286of 0.3330,4000,5001,00
PhaseTWTWTWTWTW
PEEnd-I %68,24,0864,461,43,7869,214,3473,14,78
CMPEnd-I %7,79,207,08,796,455,746.42 per7,26,135,88
The DEPEnd-I %9,40,848,350,647,780,2810,410,369,920,16
TNEnd-I %14,238,9613,337,1611,8of 37.98,6032,11the 5.2522,17
2AboutContent, %0,546,926,9549,2412,5752,3are 5.3655,995,667,01
Note: PE - pentaerythritol, CMP - cyclic nonformal, DEP - dipentaerythritol, TN - sodium formate, T - solid phase, W - liquid phase, MH2O- the mass of water, Mf- the mass of the waste filtrate.

Experience No. 1 was carried out at a ratio of water/filtrate 0,200. Installed, with the high correlation of phases formed viscous unfiltered suspension, which complicates and makes unacceptable conduct the leaching of soluble compounds from solid waste leachate.

In experiments No. 2-4 correlation of phases supported MH2O/MF=0,286-0,400, the filtering process has been fairly long for 30-19 min, the solution after filtration had a density 1,271-1,312 g/cm3. As can be seen from the data in table 1-2, with a ratio of the phases, the content of pentaerythritol in the sediment was 61.4-68,2%, and the content of impurities in the sediment was (wt.%): CMP is 6.4 to 7.7, DEP - 7,78-9,4, TN - 11.8 to 14.2 per cent (the rest is water). The high content of impurities formate soda is I in the sediment is not desirable due to the ingress of these impurities on stage crystallization of pentaerythritol and sediment pollution pentaerythritol during crystallization. The concentration of sodium formate in solution after treatment of the waste filtrate water was high values of 38.9 to 37.9%, which is advantageous for the processing solution in the sodium formate. However, the low filtration rate after processing the waste filtrate water and bad cleaning sludge pentaerythritol indicate that the modes of processing water, waste filtrate No. 2-4 are not suitable for industrial implementation.

In experiments No. 5-6 correlation of phases supported according to the claimed method MH2O/MF=0,500 of 1.00, which resulted in reduced duration of the filtration process to 14-15 min and enhance the content of pentaerythritol in the sediment to 69,2-73,1%, a slight change in the content of the DEP and CMP and a substantial decrease in the content of soluble compounds of sodium formiate to 8.6-of 5.25%. The precipitate containing such impurities can be processed into technical pentaerythritol by mixing with the solution entering the evaporation and crystallization of technical pentaerythritol. The density of the resulting solution was 1,251-1,182 g/cm3the concentration of sodium formate in the solution supplied to the obtaining of sodium formiate, was high values 22,17-32,11%, which is acceptable for filing solution through evaporation in the production of sodium formiate.

Thus, the implementation of the method of processing waste filter is and the production of pentaerythritol in examples No. 5-6, i.e. the claimed method allows to reduce the cost of implementation of the method and the toxicity of the reagents through the use of waste treatment of the filtrate with water at ambient temperature.

Techno-economic evaluation showed that using the proposed method at JSC "Metafrax" from waste leachate in addition to obtain 1241 t/year of monopentaerythritol and 3580 tons/year of sodium formiate. Total income from additional production volume will amount to 98.7 million rubles/year.

Literature

1. U.S. patent 2,780,655. Recovery of pentaerythritol by formalin extraction. / Harold I.Yalowitz. - Appl.: may 5, 1954, Publ.: 5.02.1957.

2. Berlow E., Barth, R., Snow D. PENTAERYTHRITE. - Translation from English. - M., 1963.

3. Belkin DI Scientific basis, development and industrial use of effective technologies of pentaerythritol. The dissertation on competition of a scientific degree of the doctor of technical Sciences, 1988.

Method for processing waste leachate production of pentaerythritol containing, wt.%: 32-37,81 of sodium formiate, 22-27 pentaerythritol, 10-11 cyclic nonformula, 2-3 dipentaerythritol, as well as the impurity derivatives of pentaerythritol, including the processing of the filtrate the solvent, followed by separation and disposal of the resulting liquid and solid phases, wherein the treatment is carried out with water at a ratio of water:the filtrate is equal to (0.5 to 1.0):1, and t is mperature 15-25°C With subsequent submission of the washed precipitate, on stage evaporation and crystallization to obtain technical pentaerythritol, and the solution of the filtrate on evaporation and crystallization to obtain sodium formate.



 

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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

The invention relates to an improved process for the preparation of pentaerythritol with a basic substance content of more than 98 wt.% and pentaerythritol, enriched dipentaerythritol in the amount of 5-20 wt.%, used in paint and other industries

The invention relates to a method for the simultaneous receipt of pentaerythritol and sodium formate used in the chemical, leather and paint and other industries

The invention relates to a method for pentaerythritol by the interaction of acetaldehyde with an excess of formaldehyde in the presence of sodium hydroxide

The invention relates to the production of polyhydric alcohols, in particular pentaerythritol (PE), is widely used in the manufacture of paints and varnishes, plasticizers, and relates to a method of obtaining a PE in the presence of calcium hydroxide

The invention relates to the technology of organic synthesis, in particular pentaerythritol used in paint and other industries

FIELD: organic chemistry, biotechnology.

SUBSTANCE: invention relates to variants of a method for extraction of 1,3-propanediol from enzymatic broth. The first variant involves steps for contacting enzymatic broth containing water, 1,3-propanediol and at least one impurity chosen from glycerol, glucose and butanetriol with at least one extractant chosen from alkanols, ketones, esters, acids, ethers or vegetable oils to form the first mixture. Then the first mixture is separated for the first phase and the second phase wherein the first phase comprises the greater part of extractant and at least some amount of 1,3-propanediol from enzymatic broth in the mass ratio 1,3-propanediol to at least one component taken from glycerol, glucose or butanetriol in the first phase above the mass ratio 1,3-propanediol and the same impurity in enzymatic broth before contacting enzymatic broth with the extractant wherein the second phase comprises the greater part of water and at least some amount of impurity from enzymatic broth followed by extraction of 1,3-propanediol by separation of the first phase from the second phase, contacting the first separated phase with aqueous solution to form the second mixture, and separation of the second mixture for the third and forth phases wherein the third phase comprises the greater part of the extractant from the first phase, and wherein the fourth phase comprises 1,3-propanediol and the greater part of the first amount of the first amount of aqueous solution, and wherein the mass ratio in the forth phase of 1,3-propanediol to any presenting mixture is more as compared with the mass ratio of 1,3-propanediol to the same impurity in the enzymatic broth being before contacting the enzymatic broth with the extractant, and extraction of 1,3-propanediol, and separating the fourth phase from the third phase. Invention provides enhancing purity of 1,3-propanediol.

EFFECT: improved method of extraction.

30 cl, 15 tbl, 9 dwg, 10 ex

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