Method for preparing 1,2-dichloroethane

FIELD: chemical technology.

SUBSTANCE: invention relates to a method for preparing 1,2-dichloroethane. Method involves the oxychlorination reaction of ethylene with hydrogen chloride and oxygen-containing gas and alkaline treatment of dichloroethane also. Before alkaline treatment of 1,2-dichloroethane carbon dioxide is removed that is carried out by decrease of the reaction mixture pressure comprising 1,2-dichloroethane, or by addition of inert gas wherein nitrogen is used, or by heating. Before separation of carbon dioxide the product of the 1,2-dichloroethane-containing the oxychlorination reaction is quenched, cooled and/or condensed. After separation of carbon dioxide the 1,2-dichloethane-containing reaction mixture is treated with an aqueous alkaline solution followed by its separation. The prepared 1,2-dichloroethane-containing reaction mixture is characterized by the content of chloral and/or chloral hydrate less 0.02 wt.-% but preferable less 0.005 wt.-%, and especially preferably, less 0.002 wt.-%. Invention provides reducing consumption of an alkaline solution, prevention of formation of by-side products of chloral and chloral hydrate, and preparing the pure 1,2-dichloroethane with respect to such by-side products.

EFFECT: improved preparing method.

16 cl, 3 dwg, 3 ex

 

The invention concerns a method for producing 1,2-dichloroethane, very clean in respect of Chlorella and/or chloralhydrate and carbon dioxide, which includes oxychloination of ethylene chloride with hydrogen and a gas containing oxygen, as air or oxygen, and alkaline processing of dichloroethane and 1,2-dichloroethane obtained by this method.

A known method for producing 1,2-dichloroethane is oxychloination of ethylene by means of hydrogen chloride and oxygen, and as unwanted byproducts chloral or/and chloralhydrate. The product of the method is also often contains large amounts of dissolved carbon dioxide formed as a by-product of the interaction of ethylene with oxygen.

In the publication DE 1518931 describes how oxychlorination process for producing 1,2-dichloroethane, in which unwanted chloral removed through the stage of condensation. However, only 75-80% of Chlorella can be separated from the product by using this stage. Further residual chloral by raising the pH-value is transformed into easily separated using distillation substance, such as chloroform.

Similarly, in the German patent 1468480 describes how oxychlorination process, in which by alkaline treatment of unwanted side products chloral or chloralhydrate represeuts in sodium formate and chloroform, and thus can be easily separated from the product of the method of 1,2-dichloroethane.

The drawback of both methods is that a large portion of the alkaline solution, particularly an aqueous solution of alkali metal hydroxide consumed for the neutralization of carbon dioxide, and produces a corresponding amount of carbonate of alkali metal or other salts. Therefore, must be used large quantities of alkaline solution than would be required for clean conversion of chloral or chloralhydrate. In addition, the saline ballast, separated in large numbers by neutralization must be removed from industrial installations and disposed.

Therefore, the objective of the invention was to develop a method oxychlorination process for producing 1,2-dichloroethane, which does not have the disadvantages of the known methods. In particular, the objective of the invention was to reduce the consumption of alkaline solution, and saline ballast conversion of undesirable side products Chlorella and chloralhydrate or entirely prevent their formation, and simultaneously to obtain 1,2-dichloroethane, which is characterized by only a small number of named products or even without them.

This problem is solved by a method for producing 1,2-dichloroethane is, which includes oxychloination of ethylene chloride with hydrogen and a gas containing oxygen, such as oxygen or air, as well as the alkaline treatment of the reaction mixture containing dichloroethane, and characterized especially by the fact that, prior to alkaline treatment of 1,2-dichloroethane carbon dioxide is removed from the organic phase containing 1,2-dichloroethane.

Especially preferred was that carbon dioxide can be substantially removed from the reaction mixture before the alkaline treatment of 1,2-dichloroethane, because this makes it possible to avoid a large amount of salt ballast. This preserves the industrial installation and saves time and material costs, as salt ballast must be removed from industrial installations only in the reduced volume, or more generally should not be deleted.

In addition, preferably by means of the method according to the invention can be used to reduce the number of alkaline solutions. Due to the abbreviated requirements of alkali is possible to reduce manufacturing costs. It is also very preferable and desirable from the point of view of health, as staff must use a smaller amount of alkali. Thus, in a further smaller amount of alkali necessary to dispose of. It is significant the advantage from the economic point of view, and from the point of view of the environment.

Clean or very clean EDC (EDC) according to the invention is characterized in kg EDC content of 2-chloroethanol <100 mg, especially <50 mg, preferably <20 mg, more preferably <10 mg, significantly preferred <5 mg and particularly preferably <2 mg

Very clean EDC according to the invention is characterized in kg EDC content Chlorella <20 mg, preferably <10 mg and particularly preferably <5 mg

Very clean EDC according to the invention is characterized in kg EDC content of ferric chloride <20 mg, preferably <10 mg, significantly preferred <5 mg and particularly preferably <1 mg

Preferably the method according to the invention according to the form of execution includes the following stages:

1) oxychloination ethylene chloride hydrogen and oxygen,

2) quenching, washing and/or cooling and condensation of the reaction gases, and products obtained oxychloination,

3) if necessary, the separation of the wash liquid,

4) distillation and condensation of 1,2-dichloroethane and, if necessary, with water-stage damping,

5) the separation of the aqueous and organic phases with phase 4, if necessary, after translation of the condensate containing 1,2-dichloroethane, in the separation tank

if necessary, the return water is phase to phase damping, and

if necessary, the return of gases to the stage oxychlorination process,

6) remove carbon dioxide from the phase containing 1,2-dichloroethane (from the reaction mixture),

7) alkaline processing phase containing 1,2-dichloroethane, for example, aqueous alkali,

8) the separation of the aqueous and organic phases, if necessary, after translation phase containing 1,2-dichloroethane, with the stage 7 in the separation tank, if necessary, returning the aqueous phase to the stage of extinction,

9) the allocation of 1,2-dichloroethane and

10) if necessary, the next stage of regeneration or further processing.

1,2-Dichloroethane so obtained is very pure in respect of Chlorella/chloralhydrate and carbon dioxide.

Terms of the way separate themselves known stages of the method according to the invention, especially the stage oxychlorination process, as well as the stage of the alkali treatment can be given preferably in accordance with the conditions of the method described in the publication DE 1518931 and German patent 1468480; disclosure through links included in this description.

It is preferable for the stage oxychlorination process using the catalyst, and particularly suitable for this proved to be the catalyst CuCl2or FeCl3.

Preferably, the reaction mixture prior to removal of carbon dioxide cont who live in cubic part of the washing zone or blanking, made in the form of bubble columns and containing wash liquid.

According to the following form of the method containing solids, the reaction mixture coming when known conditions of the reaction zone, which, along with a gaseous and/or liquid products of ethylene oxychlorination process under certain conditions, there is also the dust of the catalyst, is passed through the washing area; it may include, for example, the column and the lower cubic part, made in the form of bubble columns. When this reaction mixture is preferably fed in the lower part of the bubble column where it comes into close contact with contained therein a wash liquid and simultaneously quantitatively released from the dust of the catalyst. This stage of the method can also be designated as the clearing.

Used wash liquid away from the bottom part of the washing zone, for example, neutralize and served on wastewater treatment.

The gaseous portion of the reaction mixture is cooled and washed in the washing area, the gas fed into the condensation zone, which preferably is dominated by high pressure and low temperature.

There, the reaction mixture containing EDC, basically, preferably under pressure, condenses and is separated from the volatile by-products. The condensate contains process is i.i.d. carbon dioxide.

Carbon dioxide, especially in the organic phase containing 1,2-dichloroethane, can be separated by any suitable method or device. Preferably the separation of carbon dioxide from containing the 1,2-dichloroethane phase is also carried out, at least through the pressure reduction phase, for example, in the tank (the tank desorption). During this phase before decompression is characterized, for example, a pressure of around 4 bar abs., while after decompression it is characterized by pressure in the region of about 1.1 bar abs. The tank of this kind preferably has a descent for removal of carbon dioxide (gaseous), and slope for drainage containing the 1,2-dichloroethane phase (liquid). Through this descent, this liquid can be fed to the following stage of the method. The next step in the method is alkaline treatment is already very clear in respect of CO2dichloroethane to remove Chlorella and/or chloralhydrate.

In the following the preferred form of the carbon dioxide is separated from the containing 1,2-dichloroethane phase in the column by introducing an inert gas. As the inert gas can be any inert gas suitable for this stage of the method. Preferably the inert gas is nitrogen. Preferably 1,2-dichloroethane and the inert gas about the W ill result in counterflow relative to each other, to improve the mass transfer. But it may also hold method in parallel.

In another preferred form of execution 1,2-dichloroethane or containing the 1,2-dichloroethane phase before separation of the carbon dioxide is heated by heat, preferably the separation of carbon dioxide carried out additionally or alternatively via a heat exchanger. For heat supply can be used conventional methods and devices known to the specialist. Particularly preferably this stage of the method is performed using a heat exchanger.

The above methods of separation of carbon dioxide can also be combined with each other in any way.

By separating carbon dioxide according to the invention containing 1,2-dichloroethane reaction mixture, especially the organic phase may completely or substantially completely remove dissolved carbon dioxide. Preferably the organic phase containing 1,2-dichloroethane, after separation of the carbon dioxide is characterized by the content of carbon dioxide less than 0.3 wt. -%, preferably less than 0.2% of the mass. and especially preferably less than 0.06% of the mass.

The method according to the invention by simple technical means and economically possible to effectively remove dust catalyst and/or carbon dioxide is C containing the 1,2-dichloroethane phase. Only the method according to the invention leads the preferred way to significant separation of carbon dioxide, which reduces the use of the Foundation for effective decomposition Chlorella or chloralhydrate and thereby reduces salt ballast.

In a particularly preferred form of execution of the product oxychlorination process containing 1,2-dichloroethane, before the separation of carbon dioxide to extinguish.

The damping in the context of the invention, for example, in the form of cooling and condensation, means that unreacted products, such as hydrogen chloride, by means of suitable liquids, fluids, gases or gas mixtures are fully or at least largely removed. The damping according to the invention has the advantage, namely that all or the vast amount of unreacted products under oxychlorination process, removed from the phase, which serves at the following stages of the method.

Preferably the product of the method of the oxychlorination process after blanking contains less than 0,010% of the mass. hydrogen chloride, preferably less than 0.005% of the mass. and most preferably less than 0.001% of the mass. Thus, it is possible preferably to reduce adverse reactions (corrosion) or even to avoid them completely.

Particularly preferably, the damping occurs through contact with an introd the deposits in aqueous solution (washing solution), most preferably water or an aqueous alkali solution.

Alkaline treatment containing 1,2-dichloroethane phase is carried out after separation of the carbon dioxide can be carried out in any suitable manner and by conventional devices. Preferably this stage of the method is carried out with aqueous alkaline solution. When this aqueous alkaline solution is preferably characterized by a pH value above 8.5, even more preferably of 9.5.

Can then be carried out following well-known specialist methods of separation, as distillation, to separate from 1,2-dichloroethane decomposition products chloral or chloralhydrate and other components.

Organic and aqueous waste way removed from the cycle and properly disposed of or returned to the cycle. Preferably the aqueous alkaline solution obtained at the last stage of the way, return to the cycle, particularly preferably with other water phases, which are derived from other stages of the method. Return to the cycle in the context of the invention means that fashion products, intermediate products or excipients again return to the stage method and use.

In a particularly preferred form of execution of the aqueous alkaline solution alone or together with other water phases return to the stage of extinction.

Through return back the alkaline solution through the damping increases the pH value of the stage damping, thanks laundering unreacted hydrogen chloride after oxychlorination process can mainly improve. Additionally, you may at least partially be achieved additional neutralization of alkali.

Product way of 1,2-dichloroethane obtained by the method according to the invention, generally does not contain chloral and chloralhydrate. This is preferably characterized by the content of Chlorella and/or chloralhydrate less than 0.02 wt. -%, preferably less than 0.005% of the mass. and especially preferably less than 0.002% of the mass.

The following aspect of the invention concerns very clear regarding Chlorella and/or chloralhydrate 1,2-dichloroethane obtained through the above-described method.

According to the invention 1,2-dichloroethane mainly can be used in cases where chloral or chloralhydrate would be a negative impact.

The following benefits and importance of the invention follow from the claims, the drawing and the following description, which describes specific examples of carrying out the invention with reference to the drawings.

It is shown:

Figure 1 - flow chart of the method according to the invention in accordance with a first preferred form of execution,

Figure 2 - flow chart the following a preferred form of execution of the method according to the invention and

F. the D.3 - technological scheme following a preferred form of execution of the method.

Figure 1 is a flow diagram of the method according to the invention. While the resulting 1,2-dichloroethane marked EDC (EDC), and stage oxychlorination process indicated by the numeral 5. This oxychloination carried out at regular, well-known specialist conditions and in a known manner. The reaction gas from stage oxychlorination process 5 is carried through line 6 to the stage of extinction 7. The resulting reaction mixture is conducted through line 8 to the heat exchanger 21 of the tank 1, while the waste water lines wastewater 20 away from the stage damping 7. Circulating the gas from the tank 1 return line 9 to the stage oxychlorination process 5.

In the settling tank 1 is separated aqueous phase, which is in line 10 by means of pump 16 back to the stage damping 7. The organic phase containing 1,2-dichloroethane (EDC), from sump 1 drossellied in the tank 2 by means of the regulating valve 19, through the discharge line 11 of the carbon dioxide is removed leaving carbon dioxide. According to the above preferred form of execution, you can optionally enter an inert gas, in this case nitrogen, on line 13 for supplying inert gas.

After that, the device 3 phase containing 1,2-dichloroethane, is treated by the introduction of alkali on line 12. In the following the m sump 4 is separated aqueous alkaline phase from the organic phase, containing 1,2-dichloroethane, and line 14 by pump 17 return to the stage damping 7. In conclusion, due to this, the discharge line 15 of the final product get very clean in respect of Chlorella and/or chloralhydrate 1,2-dichloroethane.

Figure 2 is a flow diagram corresponding to figure 1, according to the following preferred form of execution of the invention. However, unlike the method presented in figure 1, is that the removal of carbon dioxide takes place through the column 2A in connection with the heat exchanger 18 while supplying the inert gas, in this case nitrogen, in countercurrent, with the heat exchanger 18 is in front of the regulating valve 19. Otherwise, the conduct of the method corresponds to the method presented in figure 1, so that the corresponding parts and stages of the method are denoted corresponding to figure 1.

Figure 3 shows the phase oxychlorination process 5, area washing or clearing 7, the tank 2 stage condensing 105, the desorption zone 104, the separation zone 107 and the distillation zone 108 as the Central zones. The reaction gases: hydrogen chloride, oxygen, ethylene and circulating the gas, i.e. the gas obtained by returning in the loop is heated in two heating zones 112 and 113 and sent to the stage oxychlorination process 5.

The second heating zone 113 down to 6000 m3/h is C (N.U.) hydrogen chloride in line hydrogen chloride 117 and 1545 m 3/h (N.U.) oxygen through oxygen 118 and pump on stage oxychlorination process 5 at a temperature of 140°C. In the first heating zone 112 fail 10000 m3/h (N.U.) the circulation gas circulating gas line 120 and 3000 m3/h (N.U.) ethylene at line 119 of ethylene and pump on stage oxychlorination process 5 at a temperature of 140°C.

Stage oxychlorination process 5 includes a reactor with a fluidized bed with steam to remove the heat of reaction; the reacted reaction gas is supplied from the reactor with a fluidized bed at a temperature of 210°in line 6 of the reaction gas in the lower part of the zone of clearing or washing 7. Zone 7 includes washing column (D 2.2 m) with 8 valve plates and the bottom part 7a, particularly preferably in the form of a bubble column. The reaction gas enters the lower part of the bubble column, where it comes in close contact with a wash liquid and simultaneously quantitatively released from the catalyst dust. In the area of washing 7 the reaction gas is cooled proryvnym solution down to a temperature of from 95 to 100°C.

Wash liquid from the bottom of the bubble column flows through overflow line 121 to the reservoir 2 to neutralization by sodium hydroxide solution supplied through line 114 and, in conclusion, on line 126 is fed to follow is her treatment in the effluent treatment plant. The washed and cooled reaction gases are supplied at a gas line 122 from the washing zone 7 in the condensation zone 105.

Neskondensirovannyh the circulation gas line 131 serves for the circulation compressor 106 and 120 return to the stage oxychlorination process 5. Part of the circulating gas divert on line 133 exhaust gas. Through the line 124 condensate mixture of EDC and water containing liquefied and dissolved carbon dioxide, under a pressure of about 4 bar extends at a temperature of 37°in the desorption zone 104 to a pressure of about 1.6 bar, where it divides into the rising carbon dioxide and flowing down to the bottom of the mixture of EDC and water. If necessary, separation of the water and the rest of the reaction mixture can also be carried out in advance.

In the condensation zone 105 serves 2 m3/h (N.U.) nitrogen on line 129 for mixing and condensation in an area of low pressure 104 3 m3/h (N.U.) nitrogen line 132 to stabilize the flow of carbon dioxide from the bottom, with the addition of nitrogen contributes to a more efficient and improved removal of carbon dioxide. While carbon dioxide leaving the desorption zone 104 through line 125, as the exhaust gas (33 m3/h (N.U.)) output from the process is the removal of a mixture of EDC/water flowing to the bottom line 127 after mixing with 25%sodium hydroxide solution from whether the AI 115 for separating a two-phase mixture of an alkaline aqueous phase and the phase of the EDC in the separation zone 107.

As the aqueous phase, and the phase EDC no longer contain dissolved carbon dioxide, after the filing of a solution of sodium hydroxide buffering capacity in the system through the formation of sodium bicarbonate/sodium carbonate is excluded and is excellent continuous adjustment of the setpoint pH in the range from 10.5 to 13, preferably in the area around 12 in the aqueous phase decomposition Chlorella and 2-chloroethanol.

Compliance with the pH value is controlled by means of continuous measurement.

The aqueous phase thus obtained in the separation zone 107, may be introduced as a wash liquid in the zone of clearing or washing area 102.

After an average residence time in the separation zone 107 in the area mainly from 0.5 to 3 hours, preferably about 1 hour, the upper aqueous alkaline phase (set to pH above 9.5) on line 123 return to the zone of the washing/damping 102, and the lower phase 1,2-dichloroethane on line 128 is sent to the distillation zone. The distillation zone 108 includes a column with sieve plates (D 2 m) evaporator 109, the capacitor 110 and the separator 111.

While boiling and the water fraction is removed from separator 111, is the production of purified 1,2-dichloroethane on line 130 from the cube distillation zone 108 to obtain a vinyl chloride in the decomposition of EDC.

Some of the who as part of the aqueous phase from line 123, and phase 1,2-dichloroethane from line 128 return in line 127 to provide additional mixing.

After installation start the content Chlorella, 2-chloroethanol and ferric chloride in purified 1,2-dichloroethane (EDC) was given precision definitions:

<2 mg 2-chloroethanol/kg EDC

<5 mg Chlorella/kg EDC

<1 mg of ferric chloride/kg EDC.

After continuous production within 6 weeks of the values analyzed as pollution, has not changed. Analysis of 1,2-dichloroethane showed the same results, which were obtained after start-up (see above).

In the production of about 13,500 tons of EDC Supplement of 25%aqueous sodium hydroxide solution was, in General, 327 tons, which corresponds to specific consumption and 24.2 kg/t of EDC.

The method differs in that no circulation of the suspension, if necessary containing solids, and regardless of the changes of method, and the pH in the zone of the washing and/or extracts obtained according to the invention a mixture of 1,2-dichloroethane and water from the condensation zone at a temperature of preferably from 25 to 45°by lowering the pressure after separation of the carbon dioxide desorption zone should be subjected only to an alkaline treatment with sodium hydroxide solution at controlled pH values mostly >to 8.5, preferably >9,5, especially in the area from 10.5 until 13 and residence time in the separation zone, for example, from 0.5 to 3 hours, in order to achieve effective reduction of the content of Chlorella and 2-chloroethanol in 1,2-dichloroethane and, thereby, ensure the desired quality of 1,2-dichloroethane. The share of ferric chloride in the product is always below the limit of accuracy of definition.

In the preferred form of execution of a certain part of the separated aqueous and/or organic phase may be recycled to the feed line into the zone of separation is thus achieved additional agitation.

Example 1

The method is carried out at the same time, as presented in figure 1. The oxychloination carried out under normal conditions, which are known to the expert and is therefore not explained. The reaction gases from the stage oxychlorination process 5, primarily 1,2-dichloroethane, water and unwanted byproducts - carbon dioxide, chloral or chloralhydrate, and, if necessary, other by-products is quenched with an aqueous solution, at a subsequent stage of the method, the stage of extinction 7. When this mixture of products obtained by oxychloination, washed the traces of hydrogen chloride, unreacted when oxychloination, and, if necessary, the remains of a catalyst.

Then phase containing 1,2-dichloroethane, together with water is distilled off from the stage damping and condense. In addition, products from the stage of extinction when the pressure is 2 bar to 4 bar and a temperature of from 90 to 110° With distilled suitable distiller, condense and then transferred to a separation tank, preferably the sump 1. This tank 1 is separated aqueous phase from the organic phase containing 1,2-dichloroethane. Gaseous components can be returned to the stage oxychlorination process 5. The aqueous phase is returned to the step damping 7 and lower pressure of the organic phase in the tank 2, and carbon dioxide mainly evaporates from 1,2-dichloroethane and through the descent is removed from the tank. The content of carbon dioxide in the phase containing 1,2-dichloroethane, is from 0.2 to 0.3% of the mass. of carbon dioxide per phase containing 1,2-dichloroethane.

In the next stage of the method, the organic phase containing 1,2-dichloroethane, is sent to the device 3 and spend alkaline processing. For this purpose, in the device 3 enter alkali, preferably NaOH solution, with a concentration of <10 wt. -%, thanks chloral or chloralhydrate split.

The mixture is sent to the next tank 4, which are separated from each other 1,2-dichloroethane and the alkaline aqueous phase. The alkaline aqueous phase is returned to the step damping 7, and get very clean in respect of Chlorella/chloralhydrate 1,2-dichloroethane containing Chlorella and/or chloralhydrate from less than 0.002% to 0.005% wt. per phase containing 1,2-dichloroethane.

Example 2

The way the wire is t, as shown in figure 2. At this stage of the method and the steps also correspond to figure 1 with the difference that for separation of carbon dioxide from the phase containing 1,2-dichloroethane, phase from the first separation tank, sedimentation tank 1, send in column 2A, and carbon dioxide is separated by introducing nitrogen through the inert gas supply line 13. After this stage, the phase containing 1,2-dichloroethane, characterized by a content of carbon dioxide from 0.05 to 0.1% of the mass.

Example 3

Stage of the method and the steps again mainly correspond to figure 1 with the difference that for separation of carbon dioxide from the phase containing 1,2-dichloroethane, this phase from the first separation tank, sedimentation tank 1, is subjected to column 2A indirect heat exchanger, and an additional column 2A injected nitrogen. After this stage, the phase containing 1,2-dichloroethane, characterized by a content of carbon dioxide from <0.05 to 0.06% of the mass.

The LIST of DESIGNATIONS

1 Settler

2 Tank

2A Column

3 the Device for alkaline processing

4 Sump

5 stage oxychlorination process

6 Line for reactive gas from the stage oxychlorination process

7 stage damping

7a the bottom of

8 Line with the heat exchanger

9 Line recirculation gas

10 Line is recirculated aqueous solution

11 Line removal of carbon dioxide

12 Supply of the alkaline solution

13 the Introduction of inert gas

14 the recirculation Line of an aqueous solution

15 Line of ready removal product

16 Pump

17 Pump

18, the heat Exchanger

19 Regulating valve

20 Line wastewater

21 heat Exchanger

104 Area of low pressure or desorption

105 stage condensing

106 the Circulation compressor

107 the separation Zone

108 distillation Zone

109 Vaporizer

110 Capacitor

111 Separator

112 heating Zone

113 heating Zone

114 Line

115 Line

116

117 Line of hydrogen chloride

118 Line oxygen

119 Line ethylene

120 circulation

121 Line flow

122 Line gas

123 Line (return to the washing area)

124 Line condensate

125 Line flue gas carbon dioxide

126

127 Line

128 Line

129 Line

130 the product Line

131 Line

132 Line

133 Line

1. Method for producing 1,2-dichloroethane, at which conduct oxychloination of ethylene chloride with hydrogen and a gas containing oxygen and an alkaline processing dichloroethane, wherein carbon dioxide is separated before the alkaline treatment of 1,2-dichloroethane.

2. The method according to claim 1, characterized in that the separation of carbon dioxide carried out by lowering the pressure the reaction mixture, containing 1,2-dichloroethane.

3. The method according to claim 1 or 2, characterized in that the carbon dioxide is separated from the reaction mixture containing 1,2-dichloroethane, in the column by introducing an inert gas.

4. The method according to one of the preceding paragraphs, characterized in that the inert gas is nitrogen.

5. The method according to one of the preceding paragraphs, characterized in that the carbon dioxide is separated from the reaction mixture containing 1,2-dichloroethane, by heating.

6. The method according to one of the preceding paragraphs, characterized in that the separation of carbon dioxide carried out additionally or alternatively via a heat exchanger.

7. The method according to one of the preceding paragraphs, characterized in that the reaction mixture after separation of the carbon dioxide is characterized by the content of carbon dioxide less than 0.3 wt.%, preferably less than 0.1 wt.% and especially preferably less than 0.06 wt.%.

8. The method according to one of the preceding paragraphs, characterized in that the product oxychlorination process containing 1,2-dichloroethane, before the separation of carbon dioxide is extinguished, cooled and/or condensed.

9. The method according to claim 8, characterized in that the damping is implemented by introducing a product oxychlorination process in the cubic part of the washing zone containing wash liquid and is made in the form of a bubble column./p>

10. The method according to claim 8 or 9, characterized in that the damping is realized by the introduction into contact with the aqueous alkali solution, preferably water.

11. The method according to one of the preceding paragraphs, characterized in that the reaction mixture containing 1,2-dichloroethane, after separation of the carbon dioxide treated with an aqueous alkaline solution.

12. The method according to claim 11, characterized in that the reaction mixture containing 1,2-dichloroethane or 1,2-dichloroethane after treatment aqueous alkaline solution, is separated from the aqueous alkaline solution and the aqueous alkaline solution before processing is characterized by a pH value above 8.5.

13. The method according to item 12, wherein the aqueous alkaline solution is returned to the cycle.

14. The method according to item 13, wherein the aqueous alkaline solution returns to the stage of extinction.

15. The method according to one of the preceding paragraphs, characterized in that after separation of the aqueous alkaline solution from the organic phase is set to a pH of from 10.5 to 13.

16. The method according to one of the preceding paragraphs, characterized in that the reaction mixture containing 1,2-dichloroethane, characterized by the content of Chlorella and/or chloralhydrate less than 0.02 wt.%, preferably less than 0.005 wt.% and especially preferably less than 0.002 wt.%.



 

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The invention relates to the production of 1,2-dichloroethane (ethylene dichloride , ejh) by introducing ethylene and chlorine in the circulating ejh under vigorous stirring and heat recovery

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: organic chemistry, chemical technology.

SUBSTANCE: invention relates to a method for preparing vinyl chloride monomer from ethane and ethylene. Method involves generating the outlet flow from reactor by catalytic interaction in common of ethane, ethylene, oxygen and at least one chlorine source taken among hydrogen chloride, chlorine or chlorohydrocarbon wherein the mole ratio of indicated ethane to indicated ethylene is in the range from 0.02 to 50. At the indicated stage of catalytic interaction method involves using a catalyst comprising component of rare-earth material under condition that catalyst doesn't comprise iron and copper practically and under additional condition that when component of rare-earth material represents cerium then catalyst comprises additionally at least one more rare-earth material but not cerium. Indicated outlet flow from reactor is cooled and condensed to form flow of crude product comprising the first part of hydrogen chloride and flow of crude cooled hydrogen chloride comprising the second part of indicated hydrogen chloride. Then method involves separation of indicated flow of crude product for vinyl chloride monomer as the flow product and flow of light fractions comprising the indicated first part of indicated hydrogen chloride. Then indicated flow of light fractions is recycled for catalytic interaction in common with indicated ethane, indicated ethylene, indicated oxygen and indicated chlorine source at indicated generating stage. Also, invention proposes variants of a method for producing vinyl chloride from ethane and ethylene. Invention provides preparing vinyl (chloride) from ethane and ethylene by the complete extraction of hydrogen chloride from the reactor outlet flow.

EFFECT: improved producing method.

40, 9 tbl, 3 dwg, 31 ex

FIELD: organic chemistry, chemical technology.

SUBSTANCE: invention relates to a method for preparing vinyl chloride monomer. Method involves generating outlet flow from reactor by catalytic interaction in common ethane, ethylene, oxygen and at least one source of chlorine taken among hydrogen chloride, chlorine or chlorohydrocarbon wherein the mole ratio of indicated ethane to indicated ethylene is in the range from 0.02 to 50. At this stage of catalytic interaction method involves using a catalyst comprising component of rare-earth material under condition that catalyst has no iron and copper practically and under additional condition that when component of rare-earth material represents cerium then catalyst comprises additionally at least one more component of rare-earth material being except for cerium. Indicated outlet flow from reactor is quenched to form flow of crude product that doesn't comprise hydrogen chloride practically. Flow of crude product is separated for vinyl chloride monomer flow and light fractions flow and the latter flow is recycled for catalytic interaction in common with indicated ethane, indicated ethylene, indicated oxygen and indicated chlorine source at the indicated generating stage. Also, invention proposes variants of a method in producing vinyl chloride. Invention provides the complete extraction of hydrogen chloride from the reactor outlet flow after conversion of ethane/ethylene to vinyl (chloride).

EFFECT: improved producing method.

30 cl, 5 dwg, 9 tbl, 30 ex

The invention relates to the industrial catalyst, its acquisition and its use, especially for the production of 1,2-dichloroethane (EDC) oxychloination of ethylene in the reactor with a fluidized bed or in a reactor with a fixed layer

The invention relates to a method for producing 1,2-dichloroethane by reacting Athena with hydrogen chloride and oxygen or oxygen-containing gas on copper-containing catalyst in the fluidized bed

The invention relates to methods for organochlorine products and can be used in the chemical industry for the improvement of the production of vinyl chloride from ethylene

FIELD: organic chemistry, chemical technology.

SUBSTANCE: invention relates to a method for preparing vinyl chloride monomer. Method involves generating outlet flow from reactor by catalytic interaction in common ethane, ethylene, oxygen and at least one source of chlorine taken among hydrogen chloride, chlorine or chlorohydrocarbon wherein the mole ratio of indicated ethane to indicated ethylene is in the range from 0.02 to 50. At this stage of catalytic interaction method involves using a catalyst comprising component of rare-earth material under condition that catalyst has no iron and copper practically and under additional condition that when component of rare-earth material represents cerium then catalyst comprises additionally at least one more component of rare-earth material being except for cerium. Indicated outlet flow from reactor is quenched to form flow of crude product that doesn't comprise hydrogen chloride practically. Flow of crude product is separated for vinyl chloride monomer flow and light fractions flow and the latter flow is recycled for catalytic interaction in common with indicated ethane, indicated ethylene, indicated oxygen and indicated chlorine source at the indicated generating stage. Also, invention proposes variants of a method in producing vinyl chloride. Invention provides the complete extraction of hydrogen chloride from the reactor outlet flow after conversion of ethane/ethylene to vinyl (chloride).

EFFECT: improved producing method.

30 cl, 5 dwg, 9 tbl, 30 ex

FIELD: organic chemistry, chemical technology.

SUBSTANCE: invention relates to a method for preparing vinyl chloride monomer from ethane and ethylene. Method involves generating the outlet flow from reactor by catalytic interaction in common of ethane, ethylene, oxygen and at least one chlorine source taken among hydrogen chloride, chlorine or chlorohydrocarbon wherein the mole ratio of indicated ethane to indicated ethylene is in the range from 0.02 to 50. At the indicated stage of catalytic interaction method involves using a catalyst comprising component of rare-earth material under condition that catalyst doesn't comprise iron and copper practically and under additional condition that when component of rare-earth material represents cerium then catalyst comprises additionally at least one more rare-earth material but not cerium. Indicated outlet flow from reactor is cooled and condensed to form flow of crude product comprising the first part of hydrogen chloride and flow of crude cooled hydrogen chloride comprising the second part of indicated hydrogen chloride. Then method involves separation of indicated flow of crude product for vinyl chloride monomer as the flow product and flow of light fractions comprising the indicated first part of indicated hydrogen chloride. Then indicated flow of light fractions is recycled for catalytic interaction in common with indicated ethane, indicated ethylene, indicated oxygen and indicated chlorine source at indicated generating stage. Also, invention proposes variants of a method for producing vinyl chloride from ethane and ethylene. Invention provides preparing vinyl (chloride) from ethane and ethylene by the complete extraction of hydrogen chloride from the reactor outlet flow.

EFFECT: improved producing method.

40, 9 tbl, 3 dwg, 31 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: chemical technology.

SUBSTANCE: invention relates to a method for preparing 1,2-dichloroethane. Method involves the oxychlorination reaction of ethylene with hydrogen chloride and oxygen-containing gas and alkaline treatment of dichloroethane also. Before alkaline treatment of 1,2-dichloroethane carbon dioxide is removed that is carried out by decrease of the reaction mixture pressure comprising 1,2-dichloroethane, or by addition of inert gas wherein nitrogen is used, or by heating. Before separation of carbon dioxide the product of the 1,2-dichloroethane-containing the oxychlorination reaction is quenched, cooled and/or condensed. After separation of carbon dioxide the 1,2-dichloethane-containing reaction mixture is treated with an aqueous alkaline solution followed by its separation. The prepared 1,2-dichloroethane-containing reaction mixture is characterized by the content of chloral and/or chloral hydrate less 0.02 wt.-% but preferable less 0.005 wt.-%, and especially preferably, less 0.002 wt.-%. Invention provides reducing consumption of an alkaline solution, prevention of formation of by-side products of chloral and chloral hydrate, and preparing the pure 1,2-dichloroethane with respect to such by-side products.

EFFECT: improved preparing method.

16 cl, 3 dwg, 3 ex

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