CN1840520A - Process for preparing acrylic acid-3-chloro-2-acrylate by using DD mixed agent - Google Patents
Process for preparing acrylic acid-3-chloro-2-acrylate by using DD mixed agent Download PDFInfo
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- CN1840520A CN1840520A CN 200610200302 CN200610200302A CN1840520A CN 1840520 A CN1840520 A CN 1840520A CN 200610200302 CN200610200302 CN 200610200302 CN 200610200302 A CN200610200302 A CN 200610200302A CN 1840520 A CN1840520 A CN 1840520A
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Abstract
The related preparation method for AA-3-Cl-2-propene ester with DD mixed agent comprises: with alkali, catalyst, and inhibitor, reacting with 1, 3-telone and AA, distilling to separate product with material. This invention has wide application as low cost.
Description
Technical Field
The invention relates to the technical field of organic chemical industry, relates to comprehensive utilization of chemical byproducts and preparation of acrylic ester, and particularly relates to a method for preparing acrylic acid-3-chloro-2-propenyl ester by using a DD (DD) mixing agent.
Background
Acrylic ester is an important industrial derivative of propylene, the demand of China for acrylic acid and esters thereof in 2005 exceeds 40 ten thousand tons, and the acrylic ester is mainly used in the fields of chemical fibers, textiles, coatings, leather and adhesives. The production capacity and the yield of the existing acrylic ester in China can not meet the current market demand, so that the production capacity is urgently required to be expanded, the product quality is improved and the application field is expanded by technical improvement according to the industrial characteristics.
One of the main raw materials for synthesizing the product of the invention is 1, 3-dichloropropene (including cis-isomer and trans-isomer) or the hydrolysis product thereof is claw 3-chloroallyl alcohol (including cis-isomer and trans-isomer), the invention particularly focuses on taking DD mixture as the source of 1, 3-dichloropropene, and separates 1, 2-dichloropropane in the DD mixture while synthesizing novel acrylic ester, thereby solving the problem of comprehensive utilization of the DD mixture.
The DD mixing agent is a high-boiling point byproduct generated in the production of 3-chloropropene by a propylene thermal chlorination method, the main components of the DD mixing agent are 1, 2-dichloropropane and 1, 3-dichloropropene (including cis-isomer and trans-isomer), and the 3-chloropropene is mainly used for producing epichlorohydrin. At present, the production capacity of epichlorohydrin in China is 4.5 ten thousand tons per year, about 230 kilograms of DD mixed agent is generated when one ton of epichlorohydrin is produced, and nearly ten thousand tons of DD mixed agent are generated every year. And the production device of the epichlorohydrin is increased, and the generation amount of the DD mixing agent is correspondingly increased, so that the problem of treatment and utilization of the DD mixing agent is to be solved. The development of a more effective comprehensive utilization way of the DD mixed agent has important practical significance for reducing environmental pollution and improving the utilization rate of resources.
Disclosure of Invention
The invention utilizes DD mixture as the source of 1,3-dichloropropene, and utilizes the esterification reaction between acrylate and 1, 3-dichloropropene to synthesize acrylic acid-3-chloro-2-propenyl ester, thereby achieving the purposes of reasonably utilizing resources and producing low-cost acrylic ester.
Using DD mixture as main raw material, whose main component is 1, 2-dichloropropane (CH)3CHClCH2Cl) and 1, 3-dichloropropene (ClCH ═ CHCH)2Cl), contains four forms of chloride ion, but there are significant differences in their chemical activities, with allyl chloride being the most reactive for chemical reactions. The mixed agent of acrylic acid, alkali, polymerization inhibitor and catalyst and DD is used to prepare 1, 3-dichloropropene (ClCH ═ CHCH)2Cl) will take part in the esterification reaction to generate acrylic acid-3-chlorine-2-propylene ester (CH)2＝CHCOOCH2CH ═ CHCl), the basic reaction formula is as follows:
or
The boiling point of 3-chloro-2-propenyl acrylate is much higher than that of 1, 2-dichloropropane, so that the product can be separated by distillation, and useful chemical products such as 3-chloro-2-propenyl acrylate and 1, 2-dichloropropane can be obtained.
The synthesized acrylic acid-3-chlorine-2-propylene ester comprises two cis-isomers and trans-isomers, and the structural formulas are respectively as follows:
and
the method comprises four process steps: raw material pretreatment, catalytic esterification reaction, product separation and product refining.
1. Feedstock and pretreatment of feedstock
The DD mixture which is one of the main raw materials in the invention is an industrial byproduct, namely dark brown oily liquid, the contents of main components 1, 2-dichloropropane and 1, 3-dichloropropene (including cis-isomer and trans-isomer) are more than 95 percent, and a small amount of 3-chloropropene, carbonized impurities, water and the like are also contained. Therefore, the DD mixed agent needs to be dehydrated and simply distilled to remove impurities, and 97-110 ℃ fractions are received. Because the content of the 1, 3-dichloropropene in each DD mixed agent is different, the content of the 1, 2-dichloropropane and the 1, 3-dichloropropene (including cis-isomer and trans-isomer) in each DD mixed agent needs to be analyzed by gas chromatography, and the general content is 37-75% of the 1, 2-dichloropropane and 63-23% of the 1, 3-dichloropropene (including cis-isomer and trans-isomer). The mixture is used as the basis of the proportion of the reaction raw materials, and is prepared according to the stoichiometric ratio, namely the molar ratio of 1, 3-dichloropropene to acrylic acid in the DD mixing agent of 1: 1.
The invention adopts acrylic acid as another main raw material, and industrial products of the acrylic acid are refined by reduced pressure distillation before use so as to remove polymers and impurities which may be contained.
The polymerization inhibitor for acrylic acid in the present invention includes various polymerization inhibitors for radical polymerization such as hydroquinone, p-hydroxyanisole or phenothiazine, and is preferably a radical type polymerization inhibitor such as DPPH. The polymerization inhibitor needs to be added before the catalytic esterification reaction, and the dosage of the polymerization inhibitor is 0.001-0.1% of the mass of the acrylic acid.
The alkali used in the preparation process of the product can be sodium hydroxide, potassium hydroxide, sodium carbonate or other alkaline compounds, and can also be aqueous solution of the corresponding alkali. The molar ratio of the acrylic acid to the alkali is 1: 1-1.5.
The catalyst adopted in the catalytic esterification reaction is triethylamine, cuprous chloride or a phase transfer catalyst, such as polyethylene glycol and various quaternary ammonium salts, and the dosage of the catalyst is 1-10% of the mass of acrylic acid.
2. Catalytic esterification reaction
The catalytic esterification process of the present invention may be a two-step process or a one-step process.
The two-step method includes two kinds, one is that alkali and acrylic acid are neutralized to prepare corresponding acrylate, then the produced salt is used as one raw material of esterification reaction, and the salt, DD mixing agent, catalyst and polymerization inhibitor are mixed in an esterification reactor, stirred and heated to reaction temperature, and catalytic esterification reaction is carried out. The reaction temperature can be 60-100 ℃, the reaction time can be 3-8 hours, and the reaction is carried out under normal pressure. Secondly, adding alkali into the DD mixed agent for hydrolysis to convert the 1, 3-dichloropropene into the 3-chloroallyl alcohol. Adding acrylic acid, polymerization inhibitor and catalyst into the esterification reactor, stirring and heating to reaction temperature, and carrying out catalytic esterification reaction. The reaction temperature can be 60-100 ℃, the reaction time can be 3-8 hours, and the reaction is carried out under normal pressure.
The one-step method is that DD mixing agent, acrylic acid, polymerization inhibitor, alkali and catalyst are added into an esterification reactor in sequence according to a certain proportion, stirred and heated to the reaction temperature, and catalytic esterification reaction is carried out. The reaction temperature can be 60-100 ℃, the reaction time can be 3-8 hours, and the reaction is carried out under normal pressure.
In the catalytic esterification reaction, the characteristic of azeotropy of the DD mixing agent and water can be utilized, the moisture contained in the system is removed at the reflux temperature, namely the reaction temperature, and the DD mixing agent returns to the system for reaction after standing and layering so as to utilize the completeness of the esterification reaction.
The temperature rising mode of the catalytic esterification reaction can adopt conventional heating technologies such as water bath heating, oil bath heating, electric heating, steam heating and the like, and can also adopt a microwave heating technology.
3. Product separation
After the catalytic esterification reaction is finished, the system is cooled to room temperature and stands, inorganic salt generated by the reaction is precipitated and can be directly filtered and separated out; or adding a proper amount of water into the system to dissolve the generated inorganic salt, standing for layering, and removing the water phase. If the organic phase contains a small amount of water, a proper amount of drying agent such as anhydrous magnesium sulfate can be added for drying.
The organic phase after the desalting mainly contains 1, 2-dichloropropane and acrylic acid-3-chloro-2-propenyl ester, distillation is carried out under normal pressure, 95-100 ℃ fractions are collected, namely the 1, 2-dichloropropane, the separation rate is 80-100%, the purity is 95-100%, and meanwhile, the organic phase mainly containing the acrylic acid-3-chloro-2-propenyl ester is obtained.
4. Product refinement
The acrylic acid-3-chloro-2-propenyl ester obtained by the process also contains impurities such as polymers and the like, has low purity, can be distilled and refined under the vacuum degree of 1.33KPa, and collects main fractions at 57-65 ℃, namely acrylic acid-3-chloro-2-propenyl ester, wherein the yield is more than 70% and the purity is more than 95%.
The component content of the DD mixed agent and the purity of the acrylic acid-3-chloro-2-propenyl ester can be analyzed and determined by a gas chromatograph.
The compositional analysis and structural characterization methods were as follows:
the DD mixture raw material composition and the product purity are detected and analyzed by a 103 type gas chromatography produced by Shanghai analytical instrument factory, and a chromatographic column: peg.15%, red 102 vehicle. The gas chromatographic analysis conditions of the DD mixed agent and the 1, 2-dichloropropane are as follows: the temperature of the column chamber is 90 ℃, the temperature of the heat conduction pool is 110 ℃, and the gasification temperature is 150 ℃; the gas chromatographic analysis conditions of the acrylic acid 3-chloro-2-propenyl ester are as follows: the temperature of the column chamber is 110 ℃, the temperature of the heat conduction pool is 150 ℃, and the gasification temperature is 180 ℃. The infrared spectroscopic analysis was carried out by means of an IR-435 type infrared spectrometer of Shimadzu Japan.
Carrying out reduced pressure distillation under the vacuum degree of 20mmHg, and collecting fractions at 57-65 ℃, namely the acrylic acid-3-chloro-2-propenyl ester. The physical property data are as follows:
the boiling range is 57-65 ℃/1.33KPa
Density (25 ℃ C.) 1.173g/cm3
Refractive index (25 ℃ C.) 1.4546
The acrylic acid-3-chlorine-2-propylene ester obtained by the method comprises cis-isomer and trans-isomer, has similar physical and chemical properties, contains two carbon-carbon double bonds in the structure, and does not need to be separated when in application. Can be used for producing high molecular resin materials by utilizing the self polymerization, in particular, the copolymerization with other vinyl monomers. For example, the product is initiated to polymerize at about 80 ℃ under the action of a free radical initiator benzoyl peroxide to generate an elastic resin which can swell but cannot be dissolved in aromatic hydrocarbon and halogenated hydrocarbon and cannot be melted by heating. The product can be used as a cross-linking agent of thermoplastic resin, a modifier of paint and adhesive. The invention can be synthesized by using a cheap chemical byproduct DD mixing agent as a main raw material, thereby opening up a way for producing low-cost acrylic ester. The separated 1, 2-dichloropropane is more important organic synthesis intermediate and solvent, and can be converted into useful chemical products by chemical reactions of chlorination, ammoniation, hydrolysis, elimination and the like.
Drawings
The attached figure is an infrared spectrogram of acrylic acid-3-chlorine-2-propylene ester.
Detailed Description
Example 1 (two-step method)
The DD mixture was dehydrated and briefly distilled to remove impurities, and the contents of its components were analyzed by gas chromatography. The acrylic acid is refined by reduced pressure distillation to remove polymers and impurities which may be contained.
After a stirring device, a water separator and a condenser are arranged on a three-mouth bottle, 0.5mol of acrylic acid and 0.04g of polymerization inhibitor DPPH0 are added, stirred and cooled, and then 0.5mol of sodium hydroxide is added for neutralization. Then dried in vacuo to give about 47g of sodium acrylate.
A stirring device, a condenser and a thermometer are arranged on a 500ml three-mouth bottle, and 241.3g (containing 23 percent of 1, 3-dichloropropene and 0.5mol) of DD mixed agent, 0.5mol of sodium acrylate, 0.04g of DPPH0 and 3ml of triethylamine are added in turn under stirring. Heating the mixture to 85-90 ℃ in an oil bath, and reacting for 5 hours at constant temperature. After the esterification reaction is finished, cooling to room temperature, and filtering to remove the generated inorganic salt precipitate. (or adding water to dissolve inorganic salt, standing for layering, and removing a water phase.) adding a proper amount of anhydrous magnesium sulfate into an organic phase to remove residual water, adding 0.1g of hydroquinone, distilling at normal pressure, and collecting a fraction at 95-100 ℃ to obtain the 1, 2-dichloropropane. And distilling and refining the remainder under the vacuum degree of 1.3KPa, collecting fractions at 57-65 ℃, namely acrylic acid-3-chloro-2-propenyl ester, analyzing and determining the purity of the acrylic acid-3-chloro-2-propenyl ester by a gas chromatograph, and calculating the yield of the acrylic acid-3-chloro-2-propenyl ester to be 75.6%.
Example 2 (one-step method)
The raw material pretreatment process is the same as above.
After a stirring device, a water separator and a condenser are arranged on a 500ml three-mouth bottle, 241.3g (0.5 mol of 1, 3-dichloropropene), 0.5mol of acrylic acid, 0.04g of DPPH0, 0.5mol of sodium hydroxide and 2.5ml of triethylamine are sequentially added under stirring, the mixture is stirred and heated, the reaction temperature is 85-90 ℃, the mixture is refluxed and dehydrated, the reaction time is 5 hours, the mixture is cooled to room temperature after the reaction is finished, and the generated inorganic salt precipitate is removed by suction filtration. (or adding water to dissolve inorganic salt, standing for layering, and removing a water phase.) adding a proper amount of anhydrous magnesium sulfate into an organic phase to remove residual water, adding 0.1g of hydroquinone, distilling at normal pressure, and collecting a fraction at 95-100 ℃ to obtain the 1, 2-dichloropropane. And distilling and refining the remainder under the vacuum degree of 1.3KPa, and collecting fractions at 57-65 ℃, namely the acrylic acid-3-chloro-2-propenyl ester, wherein the yield is 70.8%.
Example 3 (two-step method)
The raw material pretreatment process is the same as above.
After a stirring device, a water separator and a condenser are arranged on a 500ml three-mouth bottle, 241.3g (0.5 mol of 1, 3-dichloropropene) of DD mixed agent and 20 percent Na are sequentially added under stirring2CO3132.5g (Na) aqueous solution2CO30.25mol), stirring and heating to 50-60 ℃, reacting for 4 hours, and naturally cooling. Adding 0.5mol of acrylic acid, 0.2g of hydroquinone and 0.5g of p-toluenesulfonic acid, refluxing and dehydrating, and carrying out esterification reaction for 5 hoursWhen the reaction is finished, the reaction product is cooled to room temperature, and the generated inorganic salt precipitate is removed by suction filtration. (or adding water to dissolve inorganic salt, standing for layering, and removing a water phase.) adding a proper amount of anhydrous magnesium sulfate into an organic phase to remove residual water, adding 0.1g of hydroquinone, distilling at normal pressure, and collecting a fraction at 95-100 ℃ to obtain the 1, 2-dichloropropane. And distilling and refining the remainder under the vacuum degree of 1.3KPa, and collecting fractions at 57-65 ℃, namely the acrylic acid-3-chloro-2-propenyl ester, wherein the yield is 72.9%.
Example 4 (two-step method)
The procedure was carried out as in example 1. The conditions for the esterification reaction were changed as follows: the reaction temperature is 75-80 ℃, the reaction time is 4 hours, and the dosage of triethylamine is 2.5ml, so that the yield of the acrylic acid-3-chloro-2-propenyl ester is 6.8%.
Example 5 (two-step method)
The procedure was carried out as in example 1. The conditions for the esterification reaction were changed as follows: the reaction temperature is 75-80 ℃, the reaction time is 5 hours, and the dosage of triethylamine is 3.0ml, so that the yield of the acrylic acid-3-chloro-2-propenyl ester is 22.7%.
Example 6 (two-step method)
The procedure was carried out as in example 1. The conditions for the esterification reaction were changed as follows: the reaction temperature is 75-80 ℃, the reaction time is 6 hours, and the dosage of triethylamine is 3.5ml, so that the yield of the acrylic acid-3-chloro-2-propenyl ester is 35.3%.
Example 7 (two-step method)
The procedure was carried out as in example 1. The conditions for the esterification reaction were changedas follows: the reaction temperature is 85-90 ℃, the reaction time is 5 hours, and the dosage of triethylamine is 2.5ml, so that the yield of the acrylic acid-3-chloro-2-propenyl ester is 70.8%.
Example 8 (two-step method)
The procedure was carried out as in example 1. The conditions for the esterification reaction were changed as follows: the reaction temperature is 85-90 ℃, the reaction time is 6 hours, and the dosage of triethylamine is 3.0ml, so that the yield of the acrylic acid-3-chloro-2-propenyl ester is 63.3%.
Example 9 (two-step method)
The procedure was carried out as in example 1. The conditions for the esterification reaction were changed as follows: the reaction temperature is 85-90 ℃, the reaction time is 4 hours, and the dosage of triethylamine is 3.5ml, so that the yield of the acrylic acid-3-chloro-2-propenyl ester is 55.2%.
Example 10 (two-step method)
The procedure was carried out as in example 1. The conditions for the esterification reaction were changed as follows: the reaction temperature is 95-100 ℃, the reaction time is 6 hours, and the dosage of triethylamine is 2.5ml, so that the yield of the acrylic acid-3-chloro-2-propenyl ester is 66.6%.
Example 11 (two-step method)
The procedure was carried out as in example 1. The conditions for the esterification reaction were changed as follows: the reaction temperature is 95-100 ℃, the reaction time is 4 hours, and the dosage of triethylamine is 3.0ml, so that the yield of the acrylic acid-3-chloro-2-propenyl ester is 59.7%.
Example 12 (two-step method)
The procedure was carried out as in example 1. The conditions for the esterification reaction were changed as follows: the reaction temperature is 95-100 ℃, the reaction time is 5 hours, and the dosage of triethylamine is 3.5ml, so that the yield of the acrylic acid-3-chloro-2-propenyl ester is 57.3%.
Claims (4)
1. A method for preparing acrylic acid-3-chlorine-2-propylene ester by using DD mixed agent is characterized by comprising the following process steps:
(1) pretreatment of raw materials
Removing impurities from the DD mixed agent through dehydration and simple distillation, receiving 97-110 ℃ fraction, and refining acrylic acid through reduced pressure distillation before use;
(2) catalytic esterification reaction
Firstly, neutralizing with alkali and acrylic acid to prepare corresponding acrylate, then taking the generated salt as a raw material for esterification reaction, mixing the salt with a DD mixing agent, a catalyst and a polymerization inhibitor in an esterification reactor, stirring and heating to a reaction temperature, and carrying out catalytic esterification reaction at the reaction temperature of 60-100 ℃ for 3-8 hours, wherein the reaction is carried out under normal pressure; secondly, adding alkali into the DD mixed agent for hydrolysis to convert 1, 3-dichloropropene into 3-chloroallyl alcohol, adding acrylic acid, a polymerization inhibitor and a catalyst into an esterification reactor, stirring and heating to a reaction temperature, and carrying out catalytic esterification reaction at the reaction temperature of 60-100 ℃ for 3-8 hours at normal pressure;
the one-step method is that DD mixed agent, acrylic acid, polymerization inhibitor, alkali and catalyst are added into an esterification reactor in sequence according to a certain proportion, stirred and heated to the reaction temperature, catalytic esterification reactionis carried out, the reaction temperature is 60-100 ℃, the reaction time is 3-8 hours, and the reaction is carried out under normal pressure;
(3) product separation
After the catalytic esterification reaction is finished, cooling the system to room temperature, standing, precipitating inorganic salt generated by the reaction, and directly filtering to separate out the inorganic salt; or adding a proper amount of water into the system to dissolve the generated inorganic salt, standing for layering, and removing the water phase; distilling the organic phase subjected to the desalting at normal pressure, collecting a fraction at 95-100 ℃, namely 1, 2-dichloropropane, and simultaneously obtaining an organic phase mainly containing acrylic acid-3-chloro-2-propenyl ester;
(4) product refinement
The acrylic acid-3-chlorine-2-propylene ester obtained by the process is distilled and refined under the vacuum degree of 1.33KPa, and main fractions at 57-65 ℃ are collected, namely the acrylic acid-3-chlorine-2-propylene ester.
2. The method for preparing 3-chloro-2-propenyl acrylate with the DD mixture as claimed in claim 1, wherein the polymerization inhibitor of acrylic acid is selected from polymerization inhibitors of free radical polymerization, including hydroquinone, p-hydroxyanisole or phenothiazine, or free radical type polymerization inhibitor DPPH, and the polymerization inhibitor is added before catalytic esterification, and the amount of the polymerization inhibitor is 0.001-0.1% of the mass of acrylic acid.
3. The method for preparing 3-chloro-2-propenyl acrylate from the DD mixture according to claim 1, wherein the alkali used in the preparation process is sodium hydroxide, potassium hydroxide, sodium carbonate or other alkaline compounds, or an aqueous solution of the corresponding alkali, and the molar ratio of the alkali to the acrylic acid is 1: 1-1.5.
4. The method for preparing 3-chloro-2-propenyl acrylate by using the DD mixture as claimed in claim 1, wherein the catalyst used for the catalytic esterification reaction is triethylamine, cuprous chloride or a phase transfer catalyst, and comprises polyethylene glycol and various quaternary ammonium salts, and the amount of the catalyst is 1-10% of the mass of the acrylic acid.
5. The process for preparing 3-chloro-2-propenoic acid from DD mixture according to claim 1, wherein the 1, 3-dichloropropene and acrylic acid in the DD mixture are blended in a stoichiometric ratio of 1: 1.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2006102003029A CN100402486C (en) | 2005-03-31 | 2006-03-30 | Process for preparing acrylic acid-3-chloro-2-acrylate by using DD mixed agent |
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| Application Number | Priority Date | Filing Date | Title |
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| CN200510046146.0 | 2005-03-31 | ||
| CN200510046147.5 | 2005-03-31 | ||
| CN200510046148.X | 2005-03-31 | ||
| CN 200510046147 CN1687006A (en) | 2005-03-31 | 2005-03-31 | 2-methacrylic acid-3-chlorine-2-propylene |
| CNB2006102003029A CN100402486C (en) | 2005-03-31 | 2006-03-30 | Process for preparing acrylic acid-3-chloro-2-acrylate by using DD mixed agent |
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| CN100402486C CN100402486C (en) | 2008-07-16 |
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