CN1244584C - Synthesis method of triethylene diamine from piperazine by product - Google Patents
Synthesis method of triethylene diamine from piperazine by product Download PDFInfo
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- CN1244584C CN1244584C CN 02129060 CN02129060A CN1244584C CN 1244584 C CN1244584 C CN 1244584C CN 02129060 CN02129060 CN 02129060 CN 02129060 A CN02129060 A CN 02129060A CN 1244584 C CN1244584 C CN 1244584C
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Abstract
The present invention belongs to a synthesis technology of polyurethane catalyst-triethylenediamine, particularly to a method for preparing triethylenediamine by a side product (which mainly adopts a mixture of N-beta-hydroxyethyl piperazine, N-beta-hydroxyethylethylene diamine, N-beta-aminoethyl piperazine and a small amount of piperazine) which is used for synthesizing piperazine. The present invention uses a side product of piperazine to prepare triethylenediamine in a three-step method. The preparation of the triethylenediamine is completed mainly by a once catalytic reaction, a hydroxyethylation reaction and a secondary catalytic reaction. The preparation method of catalytic agents used in the present invention is simple. A plurality of kinds of metal nitrate are mixed according to a certain proportion. The preparation method has the advantages of simple operation, moderate reaction conditions, long service life of catalytic agents, high product yield rate, high product purity and high stability. The preparation method is convenient for industrial production.
Description
Technical field
The invention belongs to the synthesis technique of catalysts for polyurethanes triethylene diamine, definite saying so by the method for the by product synthesizing triethylene diamine (TEDA) of synthesizing piperazine.
Background technology
Triethylene diamine (TEDA) is that use is the widest at most in the polyurethane foam amine series catalysts, the catalyzer that performance is best.External a lot of to the relevant patent of triethylene diamine synthesising process research.According to employing raw material difference, mainly contain two synthetic routes, be raw material with chain amine and cyclic amine respectively, catalyst system therefor has phosphate catalyst of zeolite and metal ion-modified zeolite catalyst, metal oxide catalyst, alkalies and alkaline earth etc.For example, US 4,017, and 494 have reported with Al
2O
3Operational path for the catalyzer synthesizing triethylene diamine (TEDA); US 4,405,784 and patent such as US 4,514,567 proposed with SrHPO
4, Sr
2P
2O
7, Sr (H
2PO
4)
2And the phosphoric acid salt of other metal is the triethylene diamine synthetic route of catalyzer; US 5,162,531 and US 5,280,120 reported with the metal oxide to be the synthetic route of catalyzer; US 6,350, and 874B1 has reported with the crystalline molecular sieve to be that catalyzer is the technology of raw material coproduction triethylene diamine and piperazine with chain or cyclammonium.Existing TEDA synthetic technology is a reactant with single raw material substantially, and the yield of triethylene diamine is also lower beyond the technology of catalyzer divided by hydrophosphate, therefore, studies necessary to the synthesis technique of TEDA.
Summary of the invention
The purpose of this invention is to provide a kind of processing method by the by product synthesizing triethylene diamine (TEDA) of producing piperazine.The by product of producing piperazine mainly is the mixture of N-beta-hydroxyethyl diamines, N-beta-hydroxyethyl piperazine, N-β-aminoethyl piperazine and a small amount of piperazine, and the physico-chemical property of former three is approaching, is difficult to separate.Technology proposed by the invention is converted into triethylene diamine with the by product of synthesizing piperazine to greatest extent, has alleviated the pollution to environment when the interests of producing piperazine are improved again.
The present invention realizes with following method:
A kind ofly prepare the technology of triethylene diamine (I) by piperazine by product, mainly by a catalyzed reaction, ethoxyl etherification and quadric catalysis reaction three-step reaction are finished.
Concrete reactions steps is as follows:
1) catalyzed reaction
Piperazine by product solution with 20%～80%, through the preheating vaporization, by beds, 250～450 ℃ of control reaction temperature, preferred 280～340 ℃; The gained reaction mixture is mainly triethylene diamine, N-beta-hydroxyethyl piperazine and piperazine;
2) ethoxyl etherification
After said mixture added solvent, make the concentration of mixture reach 30%～70%, be heated to 100～150 ℃, and feed oxyethane, to piperazine fully and reacting ethylene oxide;
3) quadric catalysis reaction
The reaction solution in last step is added after solvent makes the concentration of mixture be 25%～65%, feed reactor, by beds, under 250～450 ℃, preferred 280～340 ℃; Reaction generates triethylene diamine;
Solvent described in above-mentioned each reactions steps is organic solvents such as water, benzene series solvent, ether solvent, alcoholic solvent;
The catalyst levels of above-mentioned beds is 50%～100% of a reactor effective volume.
The invention reside in and proposed by three-step reaction piperazine by product to be converted into the technology of triethylene diamine to greatest extent, and by the optimization of reaction conditions the yield (weight yield) of triethylene diamine is reached more than 60%, product purity is 99.9%.
Main chemical reactions of the present invention is as follows:
In the first step reaction, the N-beta-hydroxyethyl quadrol in the piperazine by product, N-β-aminoethyl piperazine and N-beta-hydroxyethyl piperazine change piperazine, triethylene diamine and N-beta-hydroxyethyl piperazine under the effect of catalyzer.Wherein, N-beta-hydroxyethyl piperazine and N-β-aminoethyl piperazine mainly change triethylene diamine into through katalysis, and N-beta-hydroxyethyl quadrol reacts more complicated under the effect of catalyst system therefor, main piperazine, N-beta-hydroxyethyl piperazine and the triethylene diamine of generating, and the temperature difference, three's growing amount is obviously different.
The adding appropriate solvent helps the generation of triethylene diamine as thinner, experiment showed, water and some organic solvent, for example benzene series solvent such as toluene, benzene, ether solvent such as ether, dioxane, alcoholic solvent such as ethanol, butanols etc. can both be in various degree the carrying out that helps main reaction.
Contain piperazine, N-beta-hydroxyethyl piperazine and triethylene diamine in the first step product.At this moment, can directly distill and be separated, but operate relatively difficulty and also cost higher.Therefore, we attempt wherein piperazine is converted into N-beta-hydroxyethyl piperazine, so again under the effect of catalyzer reaction make it be converted into triethylene diamine.In experiment, we feed oxyethane in the solution of the first step product, and 100～150 ℃ of fully reactions down, the consumption of gate ring oxidative ethane is so that piperazine wherein is converted into N-beta-hydroxyethyl piperazine fully.Because two nitrogen is active identical in the piperazine, generate the dihydroxy ethyl piperazine in the reaction inevitably, but under the effect of catalyzer, the dihydroxy ethyl piperazine also can be converted into triethylene diamine.The consumption of oxyethane is related to the growing amount of dihydroxy ethyl piperazine.Therefore, the suitable oxyethane consumption of control helps reducing production costs.
In the first step catalyzed reaction, catalyzer at first changes piperazine by product into piperazine and hydroxyethyl piperazine and part triethylene diamine.In this step reaction, extremely important to the control of temperature of reaction, reaction can be carried out under normal pressure, also can suitably carry out or carry out under certain nitrogen pressure under the vacuum.
After ethoxyl etherification, has only N-beta-hydroxyethyl piperazine in the product that obtains, dihydroxy ethyl piperazine and triethylene diamine.Therefore, under the effect of used in front catalyzer, the former two also can successfully be converted into triethylene diamine, thereby make in the final mixture of reaction and mainly have this target product of triethylene diamine, pass through suitable separation and purification process again, just can obtain highly purified triethylene diamine product.
In the second step catalyzed reaction, carry out smoothly for making reaction, reduce the side reaction between raw material and cracking, polymeric by-products or the raw material self, need an amount of solvent that adds to dilute, alternative solvent has water, benzene, ether, acetone etc.
The raw material of synthesizing triethylene diamine (TEDA) is the monomer of N-beta-hydroxyethyl piperazine, N-beta-hydroxyethyl quadrol, N-β-aminoethyl piperazine, piperazine or mixture arbitrarily.
Employed catalyzer making method is simple among the present invention, the nitrate of several used metals is mixed according to a certain percentage getting final product.
By weight percentage, with nitrate of baryta 5%～45%, strontium nitrate 0%～35%, cupric nitrate 0%～35%, magnesium nitrate 0%～25% for after raw material is mixed into nitrate raw material A, 2～5 times of deionized waters that add the A volume, the saturated ammonium dibasic phosphate solution that drips 1～6 times of A volume then in the system makes the nitrate precipitated in the solution;
In A weight, can add γ-Al of 0～3 times in the reaction system in advance
2O
3As carrier.
Reaction finish after leave standstill, filter, wash, drying and moulding promptly get required catalyzer.The catalyst property that makes is highly stable, use 10,000 hours continuously after, its activity reduces significantly, can be used for suitability for industrialized production.
Advantage of the present invention and effect are:
Developed a kind of hydrogen salt of many metal tripolyphosphates efficiently complex catalyst, the yield that makes its catalysis piperazine by product is apparently higher than US 4,017,494 is 56.1% and US5 of catalyzer with active aluminium sesquioxide, 162,531 is 48.6% of catalyzer with the metal oxide, with US6,350,874B1 proposes is that the reaction yield of catalyzer is similar with the crystalline molecular sieve, only a little less than US4,405,784 reports be the reaction yield of catalyzer with the strontium monophosphate series compound, but raw material of the present invention is the by product of piperazine, is not single raw material.When only using hydroxyethyl piperazine as raw material, under the effect of this catalyzer, the yield of triethylene diamine is more than 90%.
This preparation method is simple to operate, the reaction conditions gentleness, and catalyst life is long, product yield, purity height, good stability is convenient to suitability for industrialized production.
Embodiment
Further introduce technical characterstic of the present invention below by example:
Example 1:
With adding the 450ml deionized water in the mixture of 100g nitrate of baryta, 100g strontium nitrate, 50g cupric nitrate and 50g magnesium nitrate nitrate is dissolved fully, drip in the system then the saturated ammonium dibasic phosphate solution of 250ml make nitrate precipitated in the solution, reaction finish after leave standstill, filter, wash, drying and moulding promptly get required catalyzer.
Example 2:
With 80g nitrate of baryta, 50g strontium nitrate, 50g cupric nitrate and 180g γ-Al
2O
3Mixture in add the 300ml deionized water nitrate dissolved fully, drip in the system then the saturated ammonium dibasic phosphate solution of 180ml make nitrate precipitated in the solution, reaction finish after leave standstill, filter, wash, drying and moulding promptly get required catalyzer.
Example 3:
With the aqueous solution of volume pump with the piperazine by product of the speed input 40% of 0.5ml/min, vaporize through preheating, by the beds of catalyzer 25g is housed, 300 ℃ of temperature of reaction, the gained reaction mixture contains piperazine 23.7% through look-matter on-line analysis, N-hydroxyethyl piperazine 32.7%, triethylene diamine 28.5%.
After the reaction mixture 200g that the last step was obtained adds the dilution of 100ml water, be heated to boiling, speed with 40ml/min feeds oxyethane, reaction 2h, use gas chromatographic analysis then, obtain containing in the reaction solution piperazine 0.8%, hydroxyethyl piperazine 27.5%, dihydroxy ethyl piperazine 23.2%, triethylene diamine are 24.3%
After the reaction mixture that the last step was obtained adds the dilution of 50ml water, speed with 0.4ml/min feeds the beds that contains catalyzer 25g, temperature of reaction is 320 ℃, the gained reaction mixture gets triethylene diamine content through stratographic analysis and reaches 65.8%, add an amount of dimethylbenzene then, carry out extracting rectifying, can to get purity be 99.9% pure product of triethylene diamine to recrystallization again.
Example 4:
The hydroxyethyl piperazine aqueous solution 40% feeds the beds that catalyzer 30g is housed with the speed of 0.8ml/min, 310 ℃ of temperature of reaction, and the reaction solution that obtains reaches 91.8% through gas chromatographic analysis triethylene diamine content.
Example 5:
The 2000ml reaction solution of a catalyzed reaction of cumulative is joined in the four-hole bottle that thermometer is housed, homemade high efficiency packing rectifying tower is housed above, with the thermometer bulb heating, carries out atmospheric distillation then, collect the 185.3g cut at 146～148 ℃, be mainly Piperazine anhydrous; Collect the 223.4g cut at 173～175 ℃, be mainly the triethylene diamine product; Change underpressure distillation then into, under 30mmHg, be mainly the N-hydroxyethyl piperazine at the 263.2g of 148～152 ℃ of collections cut; This moment, still surplus 76.3g still in four-hole bottle was residual, was mainly high boiling by product.
Example 6:
With the aqueous solution of volume pump with the piperazine by product of the speed input 20% of 0.5ml/min, vaporize through preheating, by the beds of catalyzer 25g is housed, 300 ℃ of temperature of reaction, the gained reaction mixture is a piperazine 21.5% through look-matter on-line analysis, N-hydroxyethyl piperazine 31.2%, triethylene diamine 32.6%.
After the reaction mixture 200g that last step reaction is obtained adds the dilution of 150ml water, be heated to 100 ℃, speed with 20ml/min feeds oxyethane, reaction 4h, use gas chromatographic analysis then, obtain containing in the reaction solution piperazine 3.2%, hydroxyethyl piperazine 22.5%, dihydroxy ethyl piperazine 24.1%, triethylene diamine are 27.3%.
After the reaction mixture that last step reaction is obtained adds the dilution of 60ml water, speed with 0.2ml/min feeds the beds that contains catalyzer 25g, temperature of reaction is 300 ℃, the gained reaction mixture gets triethylene diamine content through stratographic analysis and reaches 67.3%, and can to get purity be 99.9% pure product of triethylene diamine through separating.
Example 7:
With the aqueous solution of volume pump with the piperazine by product of the speed input 60% of 1.0mL/min, vaporize through preheating, by the beds of catalyzer 35g is housed, 330 ℃ of temperature of reaction, the gained reaction mixture is a piperazine 27.5% through look-matter on-line analysis, N-hydroxyethyl piperazine 31.2%, triethylene diamine 25.6%.
After the reaction mixture 300g that last step reaction is obtained adds the dilution of 150ml water, be heated to 150 ℃, speed with 30ml/min feeds oxyethane, reaction 10h, use gas chromatographic analysis then, obtain containing in the reaction solution piperazine 0.3%, hydroxyethyl piperazine 24.5%, dihydroxy ethyl piperazine 27.3%, triethylene diamine are 29.1%.
The water that was reacted the reaction mixture adding equal volume that obtains the last step dilutes the beds that contains catalyzer 30g with the speed feeding of 0.4ml/min, temperature of reaction is 310 ℃, the gained reaction mixture gets triethylene diamine content through stratographic analysis and reaches 69.3%, and can to get purity be 99.9% pure product of triethylene diamine through separating.
Example 8:
With the ethanolic soln of volume pump with the piperazine by product of the speed input 60% of 1.0mL/min, vaporize through preheating, by the beds of catalyzer 25g is housed, 340 ℃ of temperature of reaction, the gained reaction mixture is a piperazine 25.5% through look-matter on-line analysis, N-hydroxyethyl piperazine 32.2%, triethylene diamine 29.6%.
After the reaction mixture 100g that last step reaction is obtained adds the 50ml alcohol dilution, be heated to 130 ℃, speed with 50ml/min feeds oxyethane, reaction 2h, use gas chromatographic analysis then, obtain containing in the reaction solution piperazine 2.3%, hydroxyethyl piperazine 22.5%, dihydroxy ethyl piperazine 24.1%, triethylene diamine are 27.1%.
The alcohol dilution that the reaction mixture that last step reaction is obtained adds equal volume feeds the beds that contains catalyzer 35g with the speed of 0.6ml/min, temperature of reaction is 380 ℃, the gained reaction mixture gets triethylene diamine content through stratographic analysis and reaches 66.3%, and can to get purity be 99.9% pure product of triethylene diamine through separating.
Example 9:
With the benzole soln of volume pump with the piperazine by product of the speed input 20% of 2.0mL/min, vaporize through preheating, by the beds of catalyzer 25g is housed, 350 ℃ of temperature of reaction, the gained reaction mixture is a piperazine 22.5% through look-matter on-line analysis, N-hydroxyethyl piperazine 30.2%, triethylene diamine 27.3%.
After the reaction mixture 200g that last step reaction is obtained adds the dilution of 100ml benzene, be heated to 150 ℃, speed with 40ml/min feeds oxyethane, reaction 6h, use gas chromatographic analysis then, obtain containing in the reaction solution piperazine 0.3%, hydroxyethyl piperazine 22.6%, dihydroxy ethyl piperazine 26.1%, triethylene diamine are 28.1%.
The benzene that was reacted the reaction mixture adding equal volume that obtains the last step dilutes the beds that contains catalyzer 25g with the speed feeding of 1.6ml/min, temperature of reaction is 320 ℃, the gained reaction mixture gets triethylene diamine content through stratographic analysis and reaches 58.3%, and can to get purity be 99.9% pure product of triethylene diamine through separating.
Example 10:
With the dioxane solution of volume pump with the piperazine by product of the speed input 40% of 0.5mL/min, vaporize through preheating, by the beds of catalyzer 25g is housed, 270 ℃ of temperature of reaction, the gained reaction mixture is a piperazine 23.5% through look-matter on-line analysis, N-hydroxyethyl piperazine 34.2%, triethylene diamine 29.2%.
After the reaction mixture 300g that last step reaction is obtained adds the dilution of 150ml dioxane, be heated to 150 ℃, speed with 30ml/min feeds oxyethane, reaction 8h, use gas chromatographic analysis then, obtain containing in the reaction solution piperazine 0.4%, hydroxyethyl piperazine 23.5%, dihydroxy ethyl piperazine 28.1%, triethylene diamine are 27.8%.
The dioxane that was reacted the reaction mixture adding equal volume that obtains the last step dilutes catalyzer 26g is contained in the back with the speed feeding of 1.6ml/min beds, temperature of reaction is 280 ℃, the gained reaction mixture gets triethylene diamine content through stratographic analysis and reaches 60.8%, and can to get purity be 99.9% pure product of triethylene diamine through separating.
Claims (5)
1. the method for a piperazine by product synthesizing triethylene diamine (TEDA), concrete reactions steps are as successively down:
1) catalyzed reaction
Piperazine by product solution with 20%～80%, through the preheating vaporization, by beds, 250～450 ℃ of control reaction temperature, the gained reaction mixture is mainly triethylene diamine, N-beta-hydroxyethyl piperazine and piperazine;
2) ethoxyl etherification
After said mixture added solvent, make the concentration of mixture reach 30%～70%, be heated to 100～150 ℃, and feed oxyethane, to piperazine fully and reacting ethylene oxide;
3) quadric catalysis reaction
The reaction solution in last step is added after solvent makes the concentration of mixture reach 25%～65%, feed reactor, by beds, under 250～450 ℃, reaction generates triethylene diamine;
Solvent described in above-mentioned each reactions steps is water, benzene series solvent, ether solvent, alcoholic solvent;
The catalyst levels of above-mentioned beds is 50%～100% of a reactor effective volume;
Catalyzer is by weight percentage, with nitrate of baryta 5%～45%, strontium nitrate 0%～35%, cupric nitrate 0%～35%, magnesium nitrate 0%～25% for after raw material is mixed into nitrate raw material A, 2～5 times of deionized waters that add the A volume, the saturated ammonium dibasic phosphate solution that drips 1～6 times of A volume then in the system makes the nitrate precipitated in the solution;
In A weight, can add γ-Al of 0～3 times in the reaction system in advance
2O
3As carrier;
Piperazine by product is the monomer of N-beta-hydroxyethyl piperazine, N-beta-hydroxyethyl quadrol, N-β-aminoethyl piperazine, piperazine or mixture arbitrarily.
2. a kind of according to claim 1 method of piperazine by product synthesizing triethylene diamine (TEDA), the reaction mixture that it is characterized by a catalyzed reaction of the first step can directly carry out rectifying and obtain the triethylene diamine product.
3. a kind of according to claim 1 method of piperazine by product synthesizing triethylene diamine (TEDA), it is characterized by a catalyzed reaction temperature is 280～340 ℃.
4. a kind of according to claim 1 method of piperazine by product synthesizing triethylene diamine (TEDA), it is characterized by the quadric catalysis temperature of reaction is 280～340 ℃.
5. a kind of according to claim 1 method of piperazine by product synthesizing triethylene diamine (TEDA), it is characterized by solvent is water, toluene, benzene, ether, dioxane, ethanol, butanols.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 02129060 CN1244584C (en) | 2002-08-30 | 2002-08-30 | Synthesis method of triethylene diamine from piperazine by product |
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|---|---|---|---|
| CN 02129060 CN1244584C (en) | 2002-08-30 | 2002-08-30 | Synthesis method of triethylene diamine from piperazine by product |
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| CN1244584C true CN1244584C (en) | 2006-03-08 |
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Families Citing this family (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102046629A (en) * | 2008-05-30 | 2011-05-04 | 东曹株式会社 | Process for producing hydroxyalkyltriethylenediamine compound, and catalyst composition for the production of polyurethane resin using the hydroxyalkyltriethylenediamine compound |
| JP5640332B2 (en) * | 2008-05-30 | 2014-12-17 | 東ソー株式会社 | Process for producing hydroxy (alkyl) triethylenediamines |
| JP2011037819A (en) * | 2008-11-21 | 2011-02-24 | Tosoh Corp | Method for producing hydroxyalkyltriethylenediamine |
| CN101440039B (en) * | 2008-12-11 | 2011-07-27 | 浙江工业大学 | Method for separating N-beta-hydroxyethyl-ethylene diamine from piperazine by-product |
| JP5585087B2 (en) * | 2010-01-15 | 2014-09-10 | 東ソー株式会社 | Process for producing hydroxyalkyltriethylenediamines |
| CN102000602B (en) * | 2010-11-05 | 2015-03-25 | 西安近代化学研究所 | Cyclamine catalyst |
| CN103641836B (en) * | 2013-11-21 | 2015-07-08 | 绍兴兴欣化工有限公司 | Preparation method of 2-methyl triethylene diamine |
| CN112295579A (en) * | 2019-07-31 | 2021-02-02 | 长沙理工大学 | SrHPO modified by rare earth elements and taking graphene as carrier4-WO3In the presence of a catalyst |
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2002
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