The method of producing chloroprene by dehydrochlorination of 3,4 - dichlorobutene-1

 

(57) Abstract:

Features a method of producing chloroprene, which finds use as an intermediate in industrial organic synthesis by dehydrochlorinating 3,4-dichlorobutene-1 (in the presence of lime and a polyol such as a glycol selected from (poly)ethylene glycol and (poly)propylene glycol, preferably ethylene glycol at 70-150oC, preferably lime, take in the amount of at least 0.58 M calcium per 1 mol of dichlorobutene. The method allows us to simplify the production of chloroprene. 4 C.p. f-crystals.

The present invention relates to a method for producing 2-chlorobutadiene-1,3 /"chloroprene"/ by dehydrochlorinating 3,4-sodium dichloro-1-butene /vers/ and, in particular, to a method for producing chloroprene, on the basis of vers in which vers dihydrochloride lime.

The present method of producing chloroprene is the dehydrochlorination vers sodium hydroxide. The consumption of sodium hydroxide stechiometric and, therefore, consumption greatly increases the cost of the whole process.

Therefore, in the past, attempts have been made to find a less expensive solution than using sodium hydroxide. In particular, it was proposed samosvesti.

Some ways to dehydrochlorinating vers, using lime as the primary reagent disclosed in patent references.

So, for example, JP-51/43705 discloses a system is represented by calcium hydroxide and sodium sulfate. This method is schematically represented by the equation:

2CH2= CH-CH(Cl)=CH2Cl + Ca(OH)2+ Na2SO4--> 2CH2=CH-C(Cl)=CH2+ CaSO4+ 2NaCl + 2H2O.

The main disadvantage of this method is that there are two by-product, namely calcium sulfate and sodium chloride.

And CaSO4insoluble in water, must be separated from the aqueous solution, which contains sodium chloride, and this stage is even more increases the overall cost of the process. In addition, the method disclosed in this patent, it is not possible to obtain quantitative conversion.

In this prior art, the applicant of this invention has been able to develop a way of dehydrocorydaline vers in the chloroprene, which is free from the above disadvantages.

In accordance with the foregoing, the present invention relates to a method for producing chloroprene by dehydrochlorinating 3,4-sodium dichloro-1-butene, characterized in that the group, consisting of /poly/ethylene glycol /poly/propylene glycol, and/or at least one sugar, with preference being given to ethylene glycol.

Under "lime" here refers to the calcium oxide or calcium hydroxide or mixtures thereof.

Under "/poly/glycol" refers to ethylene glycol or propylene glycol and polymers.

Under "sugars" refers to sucrose and its derivatives, i.e., mono-, oligo - or polysaccharides, which can be hydrogenated or dehydrogenation, and their analogues. As an example, glucose, sorbitol, glycerol and others.

The reaction dehydrochlorination is carried out at a temperature in the range from 70 to 150oC, better from 80 to 120oC.

Preferably, the reaction temperature was not below the lower threshold /too low reaction kinetics/, and not above the upper threshold /fast polymerization/.

In accordance with a preferred reactor is loaded with lime and glycol; then the mixture is heated to move to the desired temperature.

Through a special funnel to the reactor type vers. Better to add it after 10 to 60 minutes.

The necessity from the selected temperature, conversion speed and glycol. For example, in the presence of ethylene glycol at 100oC to get almost full quantitative conversion vers, the reaction takes 90 minutes.

In the process of formation of the chloroprene can be separated from the reaction mixture by distillation.

At the completion of the reaction, all the resulting chloroprene can almost fully assembled. The content of the chloroprene and vers in the residual mixture inside the reactor remains very small.

Lime should be present in an amount of at least 0,5 mole of calcium per mole of ice. However, it is better to use a slight excess of lime, preferably from 0.51 to 1.5 M of lime per mol vers.

If glycol is used, the molar amount of one-half of alkylene must be at least the same as the lime. The preferred option glycol is also used as a solvent, and therefore, in great abundance.

As polyglycols, their molecular weight is usually in the range from 200 to 1000, better from 300 to 800.

In accordance with another variant of the reaction system can be diluted with water or an inert solvent, in particular etilenglikolevykh florid calcium. Ethylene or propylene glycol can be regenerated by distillation, and polyglycols - extraction.

To further illustrate the present invention presents the following examples.

Example 1. System method consists of a glass reactor (capacity 200 cm3), equipped with a mechanical stirring means, an oil bath for heating, addition funnel and external capacitor pair.

The reactor is loaded with 100 g (1.61 M) of ethylene glycol and 10.4 g (0.14 M) Ca(OH)2).

The mixture was stirred and heated to 100oC.

Within 30 minutes of a drop funnel is added 31.25 g (0.25 M) of 3,4-sodium dichloro-1-butene (vers).

The reaction mixture is maintained at a temperature of 100oC with stirring for 1 hour.

At that time there were orditillitoro and collected from the liquid of 18.5 g, gas chromatography analysis showed that this number contains 74% of chloroprene and 8% of dichlorobutene.

Analysis of the residual mixture in the reactor shows that it contains 1.48 g of chloroprene /vers is no longer present/.

Conversion vers is 95.2% and the yield of chloroprene - 72% of the reacted dichlorobutene.

Example 2. In the education vers amounted to 97.6%, the output of the chloroprene - 68.9% of which came in response dichlorobutene.

Example 3. According to the method of Example 1 was used 0.25 vers, 0.68 M of ethoxyethanol, 0.24 M of ethylene glycol and 0.14 M Ca/OH/2.

Conversion vers amounted to 61.2%, and the entrance of the chloroprene - 46.8%.

Example 4. Was repeated in Example 1, but the ethylene glycol was replaced with 100 g of polyethylene glycol with an average molecular weight of 300.

After 4 hours the reaction mixture was addictionology 11.4 g, containing 86% of chloroprene and 3% vers.

The overall balance of the example shows that the degree of conversion of dichlorobutene is 99.2%, and the yield of chloroprene - 47%.

Example 5. According to the method of Example 1 was used 1 mol vers, 0.55 mol Ca(OH)2and 4 mol of propylene glycol.

After 90 minutes reaction at 81oC conversion vers was 99% and the yield of chloroprene was 60%.

Example 6. According to the method of Example 1 was used 1 mol vers, 0.55 mol CaO and 1.8 mol of ethylene glycol.

After 80 minutes of reaction at 90oC conversion vers was 100% and the yield of chloroprene was 24%.

Comparative example 7. In the same way of Example 1 was used 0.25 mol vers, 0,76 mol of ethoxyethanol and 0.25 mol Ca(OH)2.

After 4 hours at 1022and 4.97 mol of water.

After 4 hours of reaction at 92oC conversion vers amounted to 8% and the yield of chloroprene - 2%.

1. The method of producing chloroprene by dehydrochlorination of 3,4-dichlorobutene-1, wherein the dehydrochlorination is carried out in the presence of lime and at least one glycol selected from (poly)ethylene glycol and/or polypropyleneglycol, at a temperature of 70 - 150oC.

2. The method according to p. 1, characterized in that as the use glycol ethylene glycol.

3. The method according to p. 1, wherein the dehydrochlorination is carried out at a temperature of 80 - 120oC.

4. The method according to p. 1, characterized in that the lime charge in the amount of at least 0.5 M calcium per 1 mol of dichlorobutene.

5. The method according to p. 4, characterized in that the lime used in the amount of 0.51 - 1.5 M of calcium per 1 mol of dichlorobutene.

 

Same patents:

-chloroprene" target="_blank">

The invention relates to organic synthesis, in particular, to a method for producing-chloroprene

The invention relates to a method for producing 1,1,1,3,3-pentafluoropropane, which can be used as a substitute for CFC and HCFC used as the cooling medium (refrigerant), blowing agents or detergents, and especially as urethane hatebreeder tools

The invention relates to the field of chemistry of aromatic organochlorine compounds, and in particular to a method for producing 1,1-dichloro-2,2-(4-chlorophenyl)ethylene

The invention relates to organic synthesis, in particular, to a catalytic process for the production of vinylidenechloride, which is the raw material for plastics, composite materials, paints, adhesives and other valuable products

The invention relates to organic synthesis, in particular, to methods for CIS - and TRANS-1,2-dichlorethylene that are used in the process of synthesis of polymeric materials, adhesives and resins
The invention relates to organic and Organoelement chemistry, namely, the processes of detachment of atoms of halogen from various halogenated compounds

FIELD: organic synthesis catalysts.

SUBSTANCE: catalyst is prepared from allyl chloride production wastes comprising 30-50% 1,3-dichloropropenes, 30-60% 1,2-dichloropropane, and 3-5% 1,2,3-trichloropropane, which are treated at 5-10°C with 30-50% dimethylamine aqueous solution in such amount as to ensure stoichiometric ratio of dimethylamine with respect to 1,3-dichloropropenes. Resulting mixture is held at 20-25°C for 0.5-1.0 h and then 40-44 sodium hydroxide solution is added in stoichiometric amount regarding dimethylamine, after which clarified waste is added to dimethylamine at 60-70°C and stirring in amount ensuring stoichiometric ratio of dimethylamine to 1,3-dichloropropenes contained in clarified waste. Mixture is aged for 2-3 h, organic phase is separated, and remaining interaction phase is supplemented by C1-C4-alcohol or benzyl alcohol at alcohol-to-dimethylamine molar ratio 1:(1-3).

EFFECT: reduced expenses on starting materials.

2 cl, 3 ex

FIELD: chemical industry, in particular method for production of value monomer such as vinylchloride.

SUBSTANCE: claimed method includes passing of reaction mixture containing dichloroethane vapor trough catalytic layer providing dehydrochlorination of dichloroethane to vinylchloride. Catalyst has active centers having in IR-spectra of adsorbed ammonia absorption band with wave numbers in region of ν = 1410-1440 cm-1, and contains one platinum group metal as active component, and glass-fiber carrier. Carrier has in NMR29Si-specrum lines with chemical shifts of -100±3 ppm (Q3-line) and -110±3 ppm (Q4-line) in integral intensity ratio Q3/Q4 from 0.7 to 1.2; in IR-specrum it has absorption band of hydroxyls with wave number of ν = 3620-3650 cm-1 and half-width of 65-75 cm-1, and has density, measured by BET-method using argon thermal desorption, SAr = 0.5-30 m2/g, and specific surface, measured by alkali titration, SNa = 10-250 m2/g in ratio of SAr/SNa = 5-30.

EFFECT: method with high conversion ratio and selectivity.

3 cl, 2 ex

FIELD: industrial organic synthesis.

SUBSTANCE: gas-phase thermal dehydrochlorination of 1,2-dichloroethane is conducted in presence of hydrogen chloride as promoter dissolved in feed in concentration between 50 and 10000 ppm.

EFFECT: increased conversion of raw material and reduced yield of by-products.

4 cl, 1 tbl, 8 ex

FIELD: chemistry of organochlorine compounds, chemical technology.

SUBSTANCE: method involves treatment of 1,1,1-trichloro-2,2-bis-(4-chlorophenyl)-ethane with solid calcium hydroxide or a mixture of solid calcium hydroxide and solid sodium hydroxide with the content of sodium hydroxide in mixture 30%, not above, in the molar ratio 1,1,1-trichloro-2,2-bis-(4-chlorophenyl)-ethane to alkali = 1:(1.5-1.75) at heating in the presence of catalyst. As catalysts method involves benzyltrialkyl ammonium halides, preferably, benzyltriethyl ammonium chloride or benzyltrimethyl ammonium bromide, tetraalkyl ammonium halides, preferably, tetrabutyl ammonium bromide taken in the amount 0.0005-0.005 mole. Invention provides the development of a new method for preparing 1,1-dichloro-2,2-bis-(4-chlorophenyl)-ethylene allowing to enhance ecological safety of technological process and to improve quality of the end product.

EFFECT: improved method preparing.

2 cl, 15 ex

FIELD: organic chemistry, chemical technology.

SUBSTANCE: invention relates to a method for preparing vinyl chloride monomer and to a catalyst sued in catalytic preparing vinyl chloride monomer from flows comprising ethylene. Method for preparing vinyl chloride from ethylene is carried out by the oxidehydrochlorination reaction. Method involves combining reagents including ethylene, the source of oxygen and chlorine in the catalyst-containing reactor at temperature 350-500°C and under pressure from atmosphere to 3.5 MPa, i. e. under conditions providing preparing the product flow comprising vinyl chloride and ethylene. Catalyst comprises one or some rare-earth elements under condition that the atomic ratio between rare-earth metal and oxidative-reductive metal (iron and copper) is above 10 in the catalyst and under the following condition: when cerium presents then the catalyst comprises additionally at least one rare-earth element distinctive from cerium. Ethylene is recirculated from the product flow inversely for using at stage for combining reagents. Invention proposes a variant for a method for preparing vinyl chloride. Also, invention proposes variants of a method for catalytic dehydrochlorination of raw comprising one or some components taken among ethyl chloride, 1,2-dichloroethane and 1,1,2-trichloroethane in the presence of catalyst. Catalyst represents the composition of the formula MOCl or MCl3 wherein M represents a rare-earth element or mixture of rare-earth elements taken among lanthanum, cerium, neodymium, praseodymium, dysprosium, samarium, yttrium, gadolinium, erbium, ytterbium, holmium, terbium, europium, thulium and lutetium. The catalytic composition has the surface area BET value from 12 m2/g to 200 m2/g. Invention provides simplifying technology and enhanced selectivity of the method.

EFFECT: improved conversion method.

61 cl, 8 tbl, 32 ex

FIELD: industrial organic synthesis.

SUBSTANCE: invention relates to perfluoroolefins production technology, notably to heaxafluorobutadiene CF2=CF-CF=CF2. Process comprises reaction of 1,2,3,4-tetrachlorohexafluorobutane with zinc in aqueous medium at 30 to 90°C. Reaction is carried out by metering 1,2,3,4-tetrachlorohexafluorobutane into reaction vessel containing zinc and water, while simultaneously desired product formed is recovered. Advantageously, process is conducted in presence of promoter selected from acids such as sulfuric acid and hydrochloric acid, soluble weak base salts such as zinc and ammonium halides, interphase transfer catalysts such as quaternary ammonium salts, quaternary phosphonium salts, tetrakis(dialkylamino)phosphonium salts, and N,N',N"-hexaalkyl-substituted guanidinium salts, or mixtures of indicated substances.

EFFECT: increased purity of heaxafluorobutadiene and simplified technology.

4 cl, 7 ex

FIELD: petrochemical processes.

SUBSTANCE: invention relates to oxidative halogenation processes to obtain halogenated products, in particular allyl chloride and optionally propylene. Process comprises interaction of hydrocarbon having between 3 and 10 carbon atoms or halogenated derivative thereof with halogen source and optionally oxygen source in presence of catalyst at temperature above 100°C and below 600°C and pressure above 97 kPa and below 1034 kPa. Resulting olefin containing at least 3 carbon atoms and halogenated hydrocarbon containing at least 3 carbon atoms and larger number of halogen atoms than in reactant. Catalyst contains essentially iron and copper-free rare-earth metal halide or oxyhalide. Atomic ratio of rare-earth metal to iron or copper is superior to 10:1. In case of cerium-containing catalyst, catalyst has at least one more rare-earth element, amount of cerium present being less than 10 atomic % of the total amount of rare-earth elements. Advantageously, process is conducted at volumetric alkane, halogen, and oxygen supply rate above 0.1 and below 1.0 h-1, while diluent selected from group including nitrogen, helium, argon, carbon monoxide or dioxide or mixture thereof is additionally used. Halogenated product is recycled while being converted into supplementary olefin product and olefin product is recycled in order to be converted into halogenated hydrocarbon product. Optionally, allyl chloride and ethylene are obtained via interaction of propane with chlorine source in presence of catalyst.

EFFECT: increased productivity of process and improved economical characteristics.

26 cl, 1 tbl

FIELD: chemical technology.

SUBSTANCE: invention relates to a method for synthesis of chlorinated ethylene derivatives, in particular, vinyl chloride, vinylidene chloride, trichloroethylene by the dehydrochlorination reaction of corresponding chlorinated ethane derivatives. The process is carried out in the presence of sodium hydroxide aqueous solution, catalyst of interphase transfer relating to polyglycols and an extractant-promoter representing mixture of chlorinated hydrocarbons of the general formula: CnH2n +2-xClx wherein n = 10-30; x = 1-7 with molecular mass 250-305 Da and the chlorine content is 24-43% followed by isolation of end substances by the known procedures. As a catalyst of interfase transfer the method uses polyethylene glycols in the amount 0.0001-1% of the mass of the parent chlorinated ethane derivative. Extractant-promoter is used in the amount 1-10% of the mass of the parent ethane derivative. The mole ratio of chlorinated ethane derivative to sodium hydroxide = 1:(1.15-5) at the concentration of sodium hydroxide aqueous solution 5-35 wt.-%. Invention provides the development of the complex method for synthesis of chlorinated ethylene derivatives from chlorinated ethane derivatives, among them, from depleted reagents of the method or waste of corresponding industry, and increasing yield of end products.

EFFECT: improved method of synthesis.

7 cl, 1 tbl, 12 ex

Up!