JP6173908B2 - Method for producing chloro higher alkene - Google Patents

Description

  The present invention is a method for producing chlorinated hydrocarbons. More specifically, a method in which carbon tetrachloride and an alkene are reacted in the presence of an amide compound (system solvent) -iron catalyst to obtain a chloro higher-order alkane, followed by dehydrochlorination to obtain a chloro higher-order alkene. It is.

  Chlorinated hydrocarbons are important as raw materials or intermediates for producing various products such as agricultural chemicals, pharmaceuticals, and CFC substitute materials. For example, starting from 1,1,1,2,3-pentachloropropane and via 1,1,2,3-tetrachloropropene, trichloroallyldiisopropylthiocarbamate useful as a herbicide can be produced.

  As a method for producing such a chlorinated hydrocarbon, for example, a first reaction in which chloropropane is obtained by adding carbon tetrachloride to an alkene having 2 carbon atoms (unsubstituted or chlorine-substituted ethylene) to produce a higher-order carbon. And a second reaction for dehydrochlorinating the chloropropane to obtain chloropropene and a third reaction for further adding chlorine to the chloropropene to obtain the desired chloropropane are known.

  The first reaction is often carried out in a reaction system comprising a liquid phase composed of carbon tetrachloride and a gas phase mainly composed of alkenes having 2 to 4 carbon atoms. The reaction often uses a metal and a compound that forms a complex with the metal as a catalyst, and the reaction solution obtained from the first reaction contains unreacted raw materials and by-products as impurities in addition to chloro higher-order alkanes. Products, compounds used as catalysts, complexes, metals, and the like. Therefore, the reaction solution is generally subjected to a second reaction in which these impurities are separated by a method such as distillation and then dehydrochlorinated from the chloro higher alkanes.

  For example, Patent Document 1 describes an example in which ethylene and carbon tetrachloride are reacted in the presence of a phase transfer catalyst composed of metallic iron and trialkyl phosphate to form 1,1,1,3-tetrachloropropane. Has been. In Patent Document 2, carbon tetrachloride and vinyl chloride are reacted as a catalyst with iron in the presence of amides such as N, N-dimethylacetamide to produce 1,1,1,3,3-penta. A method for obtaining chloropropane is described. In the former, although the trialkyl phosphate can be efficiently separated by distillation after the completion of the first reaction, the trialkyl phosphate is a causative substance that promotes the corrosion of the incinerator. There was a problem that it was expensive.

  On the other hand, in the latter case, waste treatment of amides generated after the completion of the first reaction is inexpensive. However, after separation by distillation, dehydrochlorination and chlorination were performed in the subsequent second reaction. It was found that the reaction rate was slow compared to the case where the trialkyl phosphate and iron were used, which did not proceed, and the reaction stopped in the middle.

Japanese Examined Patent Publication No. 2-47969 JP 2001-335517 A

  Therefore, the object of the present invention is to react carbon tetrachloride with alkenes in the presence of amides and iron to obtain higher chloroalkanes, and further to carry out dehydrochlorination reaction to obtain the desired chlorohigher alkenes. Is to provide a method for efficiently producing the desired chloro higher-order alkenes without reducing the reaction rate of the dehydrochlorination reaction.

  As a result of repeated studies to solve the above problems, the present inventors have found that chloro higher-order alkanes obtained in the first reaction are included in chloro higher-order alkanes even if amides are separated by distillation. When chloro higher-order alkanes and amides are in a vapor-liquid equilibrium state in a low concentration range of amides, the difference between the composition of the gas phase and the composition of the liquid phase becomes small, so these amides are sufficiently separated. It was found that a significant amount of amides remained in the purified chloro higher alkanes, which caused the reaction to not proceed smoothly in the dehydrochlorination reaction. And the purification of the chloro higher-order alkanes obtained in the first reaction is combined with distillation, and the treatment with the adsorbent of the distillate is carried out, so that The present inventors have found that the residue of amides can be suppressed to a high degree by a simple operation, and that the dehydrochlorination reaction of the purified chloro higher-order alkanes can proceed with high reactivity, and the present invention has been completed. .

That is, the present invention relates to carbon tetrachloride and the following general formula (1)
C _a H _b Cl _c (1)
(In Formula (1), a is an integer of 2-4, b is an integer of 1-2a, and c is an integer of 0-2a-1, provided that b + c is 2a.)
An alkene represented by the following general formula (2)
R ₁ C (═O) NR ₂ R ₃ (2)
(In Formula (2), R _1, R _{2 and} R ₃ are each H or a lower alkyl group, and may be the same or different)
In the presence of iron represented by the following general formula (3)
C _{a + 1} H _b Cl _{c + 4 (3)}
(In formula (3), a, b, and c are as described in formula (1).)
And then distilling the reaction solution, and then distilling the reaction solution, and then distillate fraction containing chloro higher-order alkane represented by formula (3) as a main component. In contact with the adsorbent,
Further, the purified chloro higher-order alkanes obtained were subjected to dehydrochlorination reaction, and the general formula (4)
C _{a + 1} H _b-1 Cl _{c + 3 (4)}
(In formula (4), a, b, and c are as described in formula (1).)
A chloro higher-order alkene represented by the formula (1) is produced.

  According to the present invention, purified chloro higher-order alkanes obtained by separating and removing amides contained in the chloro-higher-order alkanes obtained from the first reaction with high accuracy can be obtained with high yield. By supplying higher-order alkanes to the dehydrochlorination reaction, the dehydrochlorination reaction can be carried out efficiently. As a result, it is possible to produce the target chloro higher alkenes efficiently and in high yield, which is extremely useful industrially.

  In the present invention, higher-order alkenes refer to alkenes having a carbon number increased from that of the raw material alkenes by an addition reaction. Further, the higher order chloroalkenes refer to chloroalkenes having an increased number of chlorine bonds as compared to the raw material chloroalkenes due to chlorination reaction.

The process for producing chloro higher alkenes of the present invention comprises carbon tetrachloride and the following general formula (1):
C _a H _b Cl _c (1)
(In Formula (1), a is an integer of 2-4, b is an integer of 1-2a, and c is an integer of 0-2a-1, provided that b + c is 2a.)
An addition reaction with alkenes represented by the following general formula (3)
C _{a + 1} H _b Cl _{c + 4 (3)}
(In formula (3), a, b, and c are as described in formula (1).)
A first reaction (addition reaction) to obtain a chloro higher-order alkane represented by:
A dehydrochlorination reaction of the chloro higher-order alkanes obtained from the first reaction is carried out to obtain the following general formula (4)
C _{a + 1} H _b-1 Cl _{c + 3 (4)}
(In formula (4), a, b, and c are as described in formula (1).)
And a second reaction (dehydrochlorination reaction) to obtain a chloro higher alkene represented by

Further, the present invention provides a method for producing chloro higher-order alkenes, wherein chlorine is supplied into a reaction solution for dehydrochlorination of purified chloro-higher-order alkanes, and the higher-order chlorine of the generated chloro higher-order alkenes. The chemical reaction is also progressed sequentially, and the general formula (5)
C _{a + 1} H _b-1 Cl _{c + 5 (5)}
(In Formula (5), a, b, and c are as described in Formula (1).)
A method for producing higher-order chloro higher-order alkanes that generates higher-order chloro higher-order alkanes represented by the formula:

  Hereinafter, the said manufacturing method is demonstrated in detail in order.

<First reaction step>
In the first reaction step of the present invention, an addition reaction between carbon tetrachloride and an alkene represented by the above formula (1) is performed to obtain a chloro higher-order alkane represented by the above formula (3).

  Examples of the alkenes represented by the above formula (1) include ethylene, vinyl chloride, 1,1-dichloroethylene, 1,2-dichloroethylene, propylene, 1-chloropropene, 1,1-dichloropropene, and 1-chlorobutene. Is mentioned. Among them, it is preferable to use ethylene or vinyl chloride because the obtained chloropropene is industrially important.

  In the above addition reaction, carbon tetrachloride is placed in a reaction vessel under a temperature and pressure condition in which the carbon tetrachloride exists as a liquid phase, and a gaseous alkene is continuously supplied thereto, A reaction that proceeds and is carried out in the presence of an iron amide catalyst.

  For example, when the alkene represented by the above formula (1) is an alkene having 2 carbon atoms, a product in which carbon tetrachloride is bonded to carbon having a relatively small number of chlorines is generated. That is, 1,1,1,3-tetrachloropropane is obtained when ethylene is used, and 1,1,1,3,3-pentachloropropane is obtained when vinyl chloride is used.

  In the above addition reaction, the alkenes represented by the formula (1) are usually supplied to the gas phase and then dissolved in the liquid phase to be subjected to the addition reaction with carbon tetrachloride. At this time, it is preferable that an amount of alkene corresponding to the amount consumed is added to the gas phase as needed, and the pressure in the gas phase is maintained almost constant. Even when alkenes are supplied to the liquid phase in a liquid state, an amount of alkenes corresponding to the amount consumed in the addition reaction with carbon tetrachloride is added as needed, and the concentration of alkenes in the liquid phase is almost constant. It is preferable to keep it constant.

  The reaction temperature of the addition reaction is preferably 90 to 160 ° C, and more preferably 105 to 140 ° C in order to achieve both a high conversion rate and a high selectivity. The reaction pressure (gas phase pressure) is determined when the alkene is in a gaseous state, for example, when an alkene having a low boiling point such as ethylene, chloroethylene, propene, or butene is supplied, the reaction system has a liquid phase at the above reaction temperature. The pressure can be maintained, but in order to achieve both high conversion and high selectivity, the reaction pressure is preferably 0.21 to 0.62 MPa (abs) in terms of 25 ° C., More preferably, it is 0.25 to 0.45 MPa (abs). And in order to raise reaction efficiency, it is preferable that the partial pressure of alkenes represented by Formula (1) is 0.11-0.52 MPa (abs) in conversion of 25 degreeC among the said reaction pressure, 0 More preferably, it is 15 to 0.35 MPa (abs). In addition, all the said pressures are absolute pressures.

  On the other hand, when the alkenes are supplied in a liquid state, the reaction pressure may be a pressure at which the reaction system can maintain a liquid phase at the above reaction temperature, in order to achieve both high conversion and high selectivity. The proportion of alkenes in the liquid phase is preferably maintained at 1 wt% or more and 5 wt% or less, more preferably 1.5 wt% or more and 4 wt% or less with respect to the weight of the entire liquid phase. In addition, as a substance mainly existing in the gas phase at the time of the addition reaction, carbon tetrachloride, alkenes, chloro higher-order alkanes, nitrogen, oxygen, carbon dioxide, and the like can be given.

  The addition reaction of the present invention is a reaction performed in the presence of an iron amide catalyst, and the iron amide catalyst is used in a liquid phase reaction system (that is, in liquid carbon tetrachloride) in a predetermined amount of iron and a predetermined amount of iron. Prepared by contacting with amides.

  Examples of the iron used here include metallic iron, pure iron, soft iron, carbon steel, ferrosilicon steel, and an alloy containing iron (for example, stainless steel). As the shape of iron, for example, it can be any shape such as powder, granule, lump, rod, sphere, plate, fiber, etc., and metal pieces that are further processed using these, distillation filling A thing etc. may be sufficient. Any of these forms can be used, but it is preferably in the form of a powder from the viewpoint of sufficiently securing the contact area between the amide and the reactant.

  The amount of iron used is preferably 0.001 mol or more, particularly 0.002 mol, based on 1 mol of carbon tetrachloride used, from the viewpoint of achieving both high reaction conversion and high selectivity. The above is preferable. The upper limit of the amount of iron used is not particularly limited. Even if the amount of iron used is increased, the activity and selectivity are hardly affected, but the absolute amount of raw material that can be introduced into the reaction can is reduced by an amount equivalent to the volume of iron, and it is wasted without being involved in the reaction. It becomes economically disadvantageous in that the amount of iron becomes larger. In addition, if iron is left in the system after the reaction and the reaction is performed again, the wasted iron can be reduced. From this viewpoint, the amount of iron used is preferably 10 mol or less, more preferably 1 mol or less, and further preferably 0.1 mol or less, relative to 1 mol of carbon tetrachloride used. It is especially preferable to set it as 0.01 mol.

Examples of the amides include the following general formula (2)
R ¹ C (═O) NR ² R ³ (2)
(In Formula (2), R _1, R _{2 and} R ₃ are each H or a lower alkyl group, and may be the same or different)
The compound represented by these can be mentioned. Here, the lower alkyl group of R _1, R _{2 and} R _{3 is} an alkyl group having 1 to 3 carbon atoms, and specific examples include CH ₃ , C ₂ H ₅ , C ₃ H _{8 and the} like. .

  In the present invention, specific examples of amides represented by the above formula (2) include N, N-dimethylacetamide, N, N-dimethylformamide, acetamide, N, N-dimethylpropionamide, N, N-dimethylbutyl. Examples thereof include amides and N, N-diethylacetamide. Of these, N, N-dimethylacetamide, which is highly reactive and is a general-purpose product, is preferable.

  The amount of the amide represented by the formula (2) should be 0.003 mol or more with respect to 1 mol of carbon tetrachloride to be used from the viewpoint of ensuring a high conversion rate and high selectivity. Preferably, it is more preferably 0.008 mol or more. The upper limit of the amount of the amide represented by the formula (2) is not particularly limited, but if the amount used is excessively large, it is economically disadvantageous in that more amides are wasted without participating in the reaction. It becomes. From this viewpoint, the amount of amide used is more preferably 0.1 mol or less, and further preferably 0.05 mol or less, relative to 1 mol of carbon tetrachloride.

The adjustment of the iron amide catalyst is preferably performed by adding the iron and amide as described above into liquid carbon tetrachloride and bringing them into contact with each other. Before starting the reaction, either by adding all of the iron and amides into the reaction system at once, or by adding a total amount of iron and part of the amides before starting the reaction, This can be done by additional addition during the process. However, the latter addition method is preferred in that the amount of catalyst required for realizing a high reaction conversion rate is small and the reaction is easily controlled.

  This addition reaction may be continued until the conversion rate of carbon tetrachloride reaches 30 to 100%, more preferably 80 to 98%. The conversion rate of carbon tetrachloride can be judged from the consumption of alkenes, and can also be grasped by directly analyzing the reaction solution by gas chromatography or the like. The reaction time is not particularly limited, but under the conditions as described above, the total reaction time is often 1 to 24 hours, and generally 2 to 16 hours. In the case of significantly deviating from this range, it is desirable to appropriately change the alkenes supply rate and reaction temperature.

  By the way, the reaction solution after the addition reaction obtained as described above is mainly composed of chloro higher-order alkanes represented by the above formula (3), and carbon tetrachloride as an unreacted raw material as an impurity, the number of carbon atoms. 2-4 alkenes, amides represented by the above formula (2), iron amide complexes, iron, ferric chloride, reaction byproducts, and the like. For this reason, the reaction solution is generally purified by distillation after removing solids such as iron and then subjected to a dehydrochlorination reaction which is the second reaction.

  However, when the addition reaction is carried out in the presence of an iron amide catalyst, as described above, the chloro higher-order alkanes obtained after distillation are supplied to the dehydrochlorination reaction, the reaction rate, conversion rate, selectivity There was a problem that decreased. As a result of diligent study, the inventors obtained knowledge that amides remaining in the higher chloroalkanes obtained after distillation and iron amide complexes are acting as reaction inhibitors in the dehydrochlorination reaction. It was. The mechanism of this reaction inhibition is not clear, but the inventors speculate as follows. That is, in the dehydrochlorination reaction, when hydrogen chloride is generated by the decomposition of chloro higher-order alkanes, it causes further decomposition of chloroalkanes and promotes the dehydrochlorination reaction. However, when amides are present, It is thought that hydrogen chloride produced by the amides is captured, and as a result, the reaction start is delayed and the dehydrochlorination reaction is not promoted. Furthermore, in addition to the above causes, when the dehydrochlorination reaction is performed in the presence of a dehydrochlorination catalyst, the dehydrochlorination catalyst has priority over amides and iron amide complexes over chloro higher alkanes. Therefore, the phenomenon that the progress of the dehydrochlorination reaction is inhibited is also added, and it is speculated that the dehydrochlorination reaction may be greatly inhibited.

  Therefore, before the reaction solution obtained from the addition reaction is subjected to the dehydrochlorination reaction which is the second reaction, amides and iron amide complexes in the reaction solution are separated and removed with higher accuracy and efficiency. There is a need. The other impurities are not particularly limited, but it is preferable to separate and remove the reaction by-products contained in the reaction solution from the viewpoint of obtaining the desired chloro higher-order alkene with high purity.

  By the way, the chloro higher-order alkanes represented by the formula (3) and the amides represented by the formula (2) contained in the reaction solution obtained from the addition reaction have a relatively close boiling point. For example, 1,1,1,3-tetrachloropropane has a boiling point of 157 ° C. as a chloro higher-order alkane, and N, N-dimethylacetamide has a boiling point as an amide represented by the formula (2) 165 ° C, close to each other. Therefore, even if it is attempted to separate these two close compounds by distillation, unless a large-scale apparatus having a large number of theoretical stages of the condensation-evaporation cycle is used as a distillation apparatus to be used, the situation is more than a certain level.

  On the other hand, a mixture of a chloro higher-order alkane represented by the formula (3) and an amide represented by the formula (2) usually has a low amide represented by the formula (2) depending on the combination thereof. The difference between the composition of the gas phase and the composition of the liquid phase when the gas-liquid equilibrium state is reached is small in the concentration range, generally in the concentration range of 100 to 1000 ppmw, particularly in the concentration range of 200 to 500 ppmw. There are many cases. That is, the molar fraction (y) of amides present in the gas phase is 1.1x ≧ y ≧ 0.9x with respect to the molar fraction (x) of amides present in the liquid phase. In the liquid phase, there is almost no difference in the abundance ratio. Therefore, even if a large-scale distillation apparatus as described above is used, or even if it is a combination of the chloro higher-order alkanes and amides that are not closely related to each other in boiling point, the addition In the distillation of the reaction solution obtained from the reaction, it has been difficult to obtain a fraction containing chloro higher-order alkanes as a main component, in which the content of amides is highly reduced, as a distillate.

  As a combination when the difference between the composition of the gas phase and the composition of the liquid phase is small when the amide represented by the above formula (2) is in a gas-liquid equilibrium state in a low concentration range of 100 to 1000 ppmw, for example, 1,1,1,3-tetrachloropropane as chloro higher alkanes and N, N-dimethylacetamide as amides, 1,1,1,3,3-pentachloropropane and amides as chloro higher alkanes N, N-dimethylacetamide and the like can be mentioned. In the combination of 1,1,1,3-tetrachloropropane and N, N-dimethylacetamide, 1,1,1,3-tetrachloropropane can be obtained by efficiently recovering 1,1,1,3-tetrachloropropane by distillation. The concentration of N, N-dimethylacetamide in 1,3-tetrachloropropane is 200 to 300 ppmw. In such a combination, it is difficult to distill 1,1,1,3-tetrachloropropane to be further purified.

  Therefore, in the distillation of the reaction solution obtained from the addition reaction, it is difficult to highly reduce the content of amides in the distillate fraction mainly composed of the chloro higher-order alkanes. When the dehydrochlorination reaction in the second step was carried out with 100 ppmw of N, N-dimethylacetamide remaining, it was inevitable that the smooth progress of the reaction was impaired as described above. Thus, the greatest feature of the present invention is that in such a method for producing a higher chloroalkene, the reaction solution obtained by the first reaction can be purified not only by the distillation but also after the treatment by the distillation. This is in combination with the treatment of bringing the distillate into contact with the adsorbent. This makes it easy to reduce the amides to a level that does not affect the progress of the dehydrochlorination reaction in the second step, which was normally only possible to remove up to several hundred ppmw orders in ordinary distillation. It is possible to efficiently produce chloro higher-order alkenes.

  The reaction solution obtained by the first reaction can be purified by distillation but not by contact with the adsorbent. However, the amount of adsorbent consumed is large, and the amide High-boiling substances such as iron chloride and chloro higher-order alkenes that are present as by-products remain in the adsorbent, making it difficult to regenerate the adsorbent and easily causing deterioration of the adsorbent. Not right.

  Further, in the purification method in which the order of the distillation step and the adsorption step is changed, the contact with the adsorbent is performed first, and then the distillation is performed, as in the above, the initial removal of the amides is roughly adsorbed. In addition to requiring a large amount of the agent, the subsequent distillation also makes it difficult to remove the amides in the order of several hundred ppmw, and a sufficient effect cannot be obtained.

<Purification step of the reaction solution obtained by the first reaction>
Hereinafter, the purification step of the reaction solution obtained by the first reaction will be described in order by dividing it into a distillation step and an adsorption step.
[Distillation process]
In the distillation step of the present invention, the reaction solution obtained from the addition reaction is subjected to distillation, and a part of the amides contained in the chloro higher-order alkane represented by the formula (3) and the coarseness of the iron amide complex are obtained. Separate and remove. First, the boiling point of the amide represented by the formula (2) used for the addition reaction and the boiling point of the chloro higher-order alkane represented by the formula (3) generated by the addition reaction were compared, and the chloro higher-order It may be determined whether the alkanes are on the high boiling point side or the low boiling point side, and the distillation method for the chloro high-order alkanes may be selected.

  For example, if the alkene of the formula (1) used for the addition reaction is ethylene and the amide represented by the formula (2) is N, N-dimethylacetamide, the resulting chloro represented by the formula (3) The higher-order alkane is 1,1,1,3-tetrachloropropane (boiling point 157 ° C.), and the boiling point is lower than that of N, N-dimethylacetamide (boiling point 165 ° C.). Therefore, 1,1,1,3-tetrachloropropane with reduced N, N-dimethylacetamide can be obtained by simple distillation that collects substances having a boiling point lower than that of N, N-dimethylacetamide.

  In the distillation step, as described above, amides and iron amide complexes may be reduced, and substances having lower boiling points than amides, such as unreacted substances and chlorinated hydrocarbons as by-products, There is no problem even if it is recovered together with the chloro higher alkane and subjected to dehydrochlorination reaction. Hereinafter, the distillation step will be described by taking as an example a case where the chloro higher-order alkane represented by the formula (3) has a lower boiling point than the amides represented by the formula (2).

  The reaction solution obtained from the first reaction is subjected to distillation, and the chloro higher-order alkane represented by the formula (3) is recovered as a distillate from the top of the column. In this case, the high boiling point residue of the kettle includes amides, iron amide complexes, hexachloroethane, etc., alkenes are ethylene, and chloro higher alkanes are 1,1,1,3-tetrachloropropane. In this case, 1,1,1,3,3-pentachloropropane, 1,1,1,5-tetrachloropentane and the like are also included as by-products.

  In addition to the above distillation, the boiling point is represented by the formula (3) in order to separate and remove the reaction by-products and the like contained in the reaction solution described above and to obtain the desired chloro higher-order alkene with higher purity. It is also possible to carry out distillation to separate and remove low-boiling substances, which are lower than the chloro higher-order alkanes. The reaction liquid obtained from the addition reaction contains by-products such as chloroform and tetrachloroethylene as by-products in addition to unreacted carbon tetrachloride as the low-boiling substances. The distillation for separating and removing the low-boiling substances may be carried out by fractionating the distillate from the top of the tower in the distillation column for separating and removing the high-boiling substances. In the first distillation column, a distillate fraction having a low boiling point lower than the chloro higher alkanes represented by the formula (3) is separated in the first distillation column, You may implement by supplying to a 2nd distillation column and isolate | separating the distillate fraction which has the chloro higher-order alkane represented by Formula (3) as a main component. In the latter method, the amides represented by the formula (2) and the iron amide complex remain in the residue of the second distillation column.

  On the other hand, when the boiling point of the amide represented by the formula (2) used for the addition reaction is lower than the boiling point of the chloro higher-order alkane represented by the formula (3) generated by the addition reaction, First, after separating the distillate fraction of the low-boiling amides, a fraction mainly composed of chloro higher alkanes represented by the formula (3) is distilled from the remaining liquid. Just do it. This distillation may be carried out by separating the distillate from the top of the column only with a single distillation column, or by using two distillation columns in the first distillation column and the low-boiling amide. The distillate fraction of the distillate is then separated, then the residue in the kettle is fed to the second distillation column, and the distillate fraction mainly composed of chloro higher alkanes represented by the formula (3) is separated. You may carry out by doing. In the latter method, the iron amide complex remains in the residue of the second distillation column.

  As the distillation column used for the distillation, those known in the art can be used without limitation, and a plate column or a packed column can be mentioned as a preferable one. The distillation tower may be performed in one tower or several towers. As the above-mentioned column tower, a cross flow tray, a shower tray, or the like can be used. As a packing in the case of using a packed distillation apparatus, a known packing such as a Raschig ring or a Lessing ring may be used, and the material thereof is not limited, and various metals, glass, resin, and the like can be used.

  Such distillation is effective if the content of the amides in the distillate fraction containing chloro higher-order alkanes as a main component can be reduced as much as possible, but is preferably 100 to 1000 ppmw, more preferably 200. It is preferable to carry out the reaction at ˜500 ppmw, more preferably 200˜300 ppmw. That is, in the next adsorption step, considering the amount of adsorbent used, it is preferably 1000 ppmw or less, more preferably 500 ppmw or less, and even more preferably 300 ppmw or less. When the combination of the chloro higher-order alkane represented by the formula (3) and the amide represented by the formula (2) is in a gas-liquid equilibrium state in the low concentration range, the composition of the gas phase and the liquid phase If the difference in composition is small, it is preferable to further reduce the amides to the vicinity of the vapor-liquid equilibrium composition in the range of the amide content. In addition, when the boiling points of chloro higher-order alkanes and amides are close, a large-scale distillation column is required to reduce with high accuracy, and the equipment cost increases. Accordingly, the content of amides is preferably 100 ppmw or more, and more preferably 200 ppmw or more, based on the weight of the chloro higher-order alkanes.

  The distillation operation is not particularly limited, but the top of the column is adjusted so that the content of amides in the distillate fraction mainly composed of chloro higher-order alkanes supplied to the subsequent adsorption step is in the above range. It is preferable to operate by adjusting the temperature of the column, the temperature at the bottom of the column, the pressure in the column, the reflux ratio, the number of stages, and the like.

  For example, in the distillation operation for separating and removing high-boiling substances, the temperature range at the bottom of the column is preferably 20 ° C to 200 ° C, more preferably 50 ° C to 150 ° C, and 70 ° C to 120 ° C. It is more preferable to carry out within a range. When the temperature at the bottom of the column is higher than the above range, chloro higher-order alkanes are easily decomposed and the yield is lowered. When the temperature is lower than the above range, it is necessary to cool the top of the column to lower the temperature at the top of the column than the bottom of the column, so that the energy required for cooling increases and the pressure in the column must be very low. In other words, the cost of the equipment and the operating cost are high.

  The pressure during distillation may be a pressure at which the chloro higher-order alkane represented by the formula (3) vaporizes and reaches the top of the distillation tower within the above temperature range. Although it depends on the temperature at the top of the column, it is preferably 1 kPa (abs) to 100 kPa (abs), more preferably 5 kPa (abs) to 50 kPa (abs). The temperature at the top of the column may be adjusted so that the chloro higher-order alkanes represented by the formula (3) recovered under the above pressure reach the column top as a gas, and the chloro higher-order alkanes are discharged out of the distillation column. It is necessary to cool appropriately so that it will not be. For example, in the case of 1,1,1,3-tetrachloropropane, the temperature at the bottom of the column is 88-100 ° C., the temperature at the top of the column is about 87 ° C., and the pressure during distillation is 10 kPa (abs). And can be recovered in high yield.

  In the distillation operation for separating and removing low-boiling substances, the temperature range at the bottom of the column is preferably 20 ° C to 200 ° C, more preferably 50 ° C to 120 ° C. When the temperature at the bottom of the column exceeds the above range, the chloro higher-order alkane represented by the formula (3) is likely to be decomposed and the yield is lowered. If the temperature is lower than the above range, it is necessary to cool the top of the tower, the energy required for cooling increases, and the pressure in the tower must be very low, which increases the cost of equipment and operation. Become.

  As for the pressure during distillation, the pressure during distillation is within the above temperature range, and the chloro higher alkanes represented by the formula (3) remain at the bottom of the tower as the bottom of the kettle, and the low-boiling substances are vaporized. What is necessary is just to make it the pressure which reaches | attains to the top, and although it changes with the kind of this chloro higher-order alkane and the temperature of the distillation tower top, it is preferable to set it as 1 kPa (abs) -100 kPa (abs), and 5 kPa (abs) -50 kPa ( abs). The temperature at the top of the column may be adjusted so that the low-boiling substances recovered under the pressure reach the top of the column as a gas.

  During the distillation, it is not particularly necessary to add an additive, but a stabilizer may be added in order to suppress the decomposition of the target chloro higher alkanes. Examples of the stabilizer include various phenols, for example, phenols substituted with an alkoxy group and phenols substituted with an allyl group. Specific examples of phenols substituted with an allyl group include o-allylphenol, m-allylphenol, p-allylphenol, 4-allyl-2-methoxyphenol (eugenol), 2-methoxy-4- (1 -Propenyl) phenol (isoeugenol) and the like. These allyl-substituted phenols may be used alone or in combination.

  In the present invention, the method for measuring the purity of chloro higher-order alkanes and the content of amides in the distillate uses gas chromatography for separation and a flame ionization detector (FID) as a detector. Used, each means a quantified value.

  In the distillation process, when two distillation towers are used to separate and remove high-boiling substances and to remove low-boiling substances, various phenols are added as stabilizers during distillation. In this case, since the boiling point of the phenols is higher than that of the chloro higher-order alkanes represented by the formula (3), by providing distillation for separating and removing high-boiling substances at the end of the distillation step, Decomposition can be prevented efficiently.

[Adsorption process]
Next, a distillate mainly composed of chloro higher alkanes obtained from the top of the column by distillation is brought into contact with an adsorbent, and amides remaining in the distillate are further adsorbed and removed. Higher alkanes are obtained.

  Examples of the adsorbent include silica gel, zeolite, activated alumina and the like. Of these, silica gel and zeolite are preferable, and silica gel is more preferable. The average particle diameter of these adsorbents is preferably 0.05 to 10 mm, and more preferably 0.5 to 5 mm. The average pore diameter of the adsorbent is not particularly limited, but when the adsorbent is silica gel, it is preferable to use one having an average pore diameter of 1 to 30 nm. The pore volume of the adsorbent is preferably 0.2 ml / g or more.

  The contact between the distillate and the adsorbent is preferably performed by passing the distillate in a liquid state through the adsorbent. As the operation method, general adsorption operations such as a stirring bed type, a fixed bed type, a fluidized bed type, and a moving bed type can be performed. Of these, the fixed bed type, fluidized bed type, and moving bed type are preferable from the viewpoint that the adsorbent can be used efficiently, and the fixed bed type is more preferable from the viewpoint of easy operation and low equipment cost.

  The temperature and pressure at the time of adsorption are not particularly limited as long as the distillate brought into contact with the adsorbent is in a liquid state. However, since the amount of adsorption decreases when the temperature is high, the temperature is preferably 100 ° C. or lower, more preferably 60 ° C. or lower, and further preferably 40 ° C. or lower. On the other hand, when the temperature is low, the viscosity of the liquid increases and the operability is lowered, and cooling costs are required. Therefore, it is preferably −20 ° C. or higher, more preferably 0 ° C. or higher. More preferably, the temperature is higher than or equal to ° C.

  The amount of the adsorbent used is 5 to 200, more preferably 10 to 50, based on the weight of the amides contained in the chloro higher alkanes. The contact time is preferably 0.1 to 72 hours. In the case of stirring layer type adsorption, 4 to 72 hours are more preferable. In the case of fixed bed type adsorption, 0.2 to 12 hours are more preferable.

  If the concentration of amides in the purified chloro higher alkanes obtained after contact with the adsorbent is too high, the dehydrochlorination reaction of the subsequent second reaction is difficult to proceed as described above. Preferably it is 50 ppmw or less, more preferably 10 ppmw or less, and even more preferably 1 ppmw or less. There is no particular limitation on the method for measuring the purity of the purified chloro higher-order alkanes and the content of amides, but the purity of the chloro higher-order alkanes and the content of amides in the distillate in the distillation step described above are not limited. It can be performed in the same manner as the measuring method.

  By using the purified chloro higher-order alkanes thus obtained for the dehydrochlorination reaction, the dehydrochlorination reaction can be carried out efficiently without hindering.

<Second reaction step>
In the second reaction of the present invention, the chloro higher alkene represented by the above formula (4) is obtained by subjecting the purified chloro higher alkane obtained from the adsorption step to a dehydrochlorination reaction.

  In the present invention, the dehydrochlorination reaction is not particularly limited and can be carried out by a known method such as a method using a dehydrochlorination catalyst, a method of heating to a high temperature, a method of contacting with an alkaline aqueous solution and the like. Especially, it is preferable at the point which the equipment which requires the method using a dehydrochlorination catalyst becomes simple.

  As the dehydrochlorination catalyst, a known catalyst can be used without limitation, and for example, a substance acting as a Lewis acid can be used. Specific examples include anhydrous ferric chloride, anhydrous aluminum chloride, lead chloride, and metallic iron. Among them, it is preferable to use anhydrous ferric chloride or anhydrous aluminum chloride having high activity.

When the dehydrochlorination reaction is carried out using the above catalyst, if the amount of the catalyst is too large, dimerization of the chloro higher-order alkane represented by the above formula (3) proceeds, and the desired formula (4) There is a tendency that the selectivity of the chloro higher-order alkene represented is lowered, and when it is too small, the reaction rate of the dehydrochlorination reaction tends to be slow. Therefore, the amount of the catalyst is preferably 2.0 × 10 ^{−5 to} 2.0 × 10 ⁻² mol, based on 1 mol of chloro higher-order alkanes to be subjected to the reaction, It is more preferably ^{−5 to} 1.0 × 10 ⁻³ mol. The reaction temperature may be appropriately set depending on the catalyst used, but is usually 0 to 150 ° C.

  The supply into the reactor may be performed before or after the supply of the chloro higher-order alkanes, and regardless of the batch reaction or the continuous reaction, the predetermined amount of the whole amount may be initially supplied at once. During the reaction, it may be divided and supplied arbitrarily or continuously. Further, anhydrous aluminum chloride may be dissolved in chloro higher alkanes outside the reactor, and this solution may be supplied to the reactor.

  The dehydrochlorination reaction of higher-order chloroalkanes carried out in the presence of a catalyst is promoted as the temperature increases. Therefore, the reaction temperature may be appropriately set depending on the catalyst used, but is usually 0 to 150 ° C. If the temperature is too high relative to the type of catalyst used, the reactivity of the resulting chloro higher alkenes increases, and by-products are produced by dimerization or further reaction, and the desired formula (4) On the other hand, if the temperature is too low, it takes time to dissolve the catalyst and the reaction rate of the dehydrochlorination reaction tends to be slow. For example, when anhydrous aluminum chloride is used as the catalyst, it takes about 1 to 6 hours at a reaction temperature of 0 to 100 ° C.

  The reaction time depends on the size of the reaction vessel, the amount of charge, the reaction temperature, etc., but it cannot be said unconditionally, but if it is too short, the conversion rate of the chloro higher alkane is low, and if it is too long, the side reaction proceeds and the chloro higher alkene is advanced. Since the selectivity to is reduced, it is preferably 30 minutes to 6 hours.

  After completion of the reaction, the hydrogen chloride concentration in the liquid can be lowered by blowing gas into the reaction liquid. Lowering the hydrogen chloride concentration in the liquid is preferable for preventing side reactions, preventing corrosion of the reactor, and safety. The gas to be blown in is not particularly limited as long as it is an inert gas with respect to the reactant and the chloro higher alkene represented by the formula (4). For example, nitrogen and argon are fried.

  After supplying an inert gas, a Lewis base that suppresses the function of the Lewis acid catalyst can be added to the Lewis acid catalyst. By suppressing the action of the Lewis acid catalyst, unwanted side reactions can be prevented from progressing. As the Lewis base, a known compound that acts as a Lewis base can be used without any particular limitation. For example, water, alcohol compounds, carbonyl compounds, nitrile compounds, phenol compounds and the like can be mentioned. Of these, alcohol compounds, carbonyl compounds, nitrile compounds, and phenol compounds are preferable in consideration of corrosion of the reactor.

  Specific examples of the phenol compound include phenol and cresol (ortho, meta, para). Phenol compounds substituted with an allyl group can also be suitably used. Specific examples include o-allylphenol, m-allylphenol, p-allylphenol, 4-allyl-2-methoxyphenol (eugenol), 2- And methoxy-4- (1-propenyl) phenol (isoeugenol).

  Only one of these compounds may be used, or two or more thereof may be used. The amount of the Lewis base added to the reaction system is not particularly limited as long as it is more than the amount capable of deactivating the used dehydrochlorination catalyst. Often only increases. As a measure of the amount added, it is preferably 50% to 300%, more preferably 80% to 150%, more preferably 80% to 150%, based on the amount of dehydrochlorination catalyst added to the chloro higher-order alkane represented by formula (3). Preferably 90% to 120% of the substance Lewis base is added.

  The chloro higher alkene represented by the formula (4) thus obtained can be purified by a known method. In the case of purification by distillation, in addition to the removal of the anhydrous aluminum chloride, it is preferable to perform distillation after adding a stabilizer. Examples of the stabilizer include various phenols, for example, phenols substituted with an alkoxy group and phenols substituted with an allyl group. Specific examples of phenols substituted with an allyl group include o-allylphenol, m-allylphenol, p-allylphenol, 4-allyl-2-methoxyphenol (eugenol), 2-methoxy-4- (1 -Propenyl) phenol (isoeugenol) and the like. These allyl-substituted phenols may be used alone or in combination.

  Further, in the second reaction of the present invention, during the dehydrochlorination reaction, chlorine is supplied into the reaction solution, and chlorine is added to the generated chloro higher alkenes. May be advanced at the same time to obtain higher-order chloro higher-order alkanes represented by the following general formula (5).

C _{a + 1} H _b-1 Cl _{c + 5} (5)
(In Formula (5), a, b, and c are as described in Formula (1).)
Specifically, when the higher chloroalkane represented by the above formula (3) is 1,1,1,3-tetrachloropropane and anhydrous aluminum chloride is used as a dehydrochlorination catalyst, first, a reaction vessel The 1,1,1,3-tetrachloropropane contained therein proceeds with dehydrochlorination using aluminum chloride as a catalyst, and 1,1,3-trichloropropene is produced as a reaction intermediate. Subsequently, chlorine gas supplied into the reaction solution is added to the 1,1,3-trichloropropene, and 1,1,1,2,3-pentachloropropane is produced as a higher-order chloro higher-order alkane.

  When the chlorination reaction is performed simultaneously with the dehydrochlorination reaction, it is preferable to use anhydrous aluminum chloride as a catalyst in the dehydrochlorination reaction step. By using anhydrous aluminum chloride, the desired higher-order chloro higher-order alkanes can be obtained at a much lower temperature and higher selectivity than when other Lewis acids such as iron chloride are used.

When there is no dissolved aluminum chloride in the reaction system, rather than dehydrochlorination reaction to chloropropene represented by formula (4) by dehydrochlorination of chloropropane represented by formula (2), Since the substitution reaction of chlorine with chloropropane represented by the formula (2) proceeds, for example, when the chloropropane represented by the formula (2) is 1,1,1,3-tetrachloropropane, 1,1,1, By-products such as 1,3,3-pentachloropropane are produced, and the selectivity of the desired 1,1,1,2,3-pentachloropropane tends to decrease.
Therefore, it is desirable to supply chlorine after at least a part of anhydrous aluminum chloride is dissolved and the dehydrochlorination reaction is started, and it is important to appropriately adjust the amount of dissolution of anhydrous aluminum chloride. Whether or not anhydrous aluminum chloride is dissolved can be confirmed by a change in the color tone of the reaction solution. For example, when it is dissolved in 1,1,1,3-tetrachloropropane, it becomes blue when it is almost colorless.

  In consideration of the reaction efficiency, the supply amount of chlorine is preferably 0.9 mol or more, more preferably 1 mol or more with respect to 1 mol of chloro higher alkanes subjected to dehydrochlorination reaction. More preferably, it is 1.1 mol or more. On the other hand, too much chlorine increases the amount of useless chlorine that does not contribute to the reaction, so it is preferably 2.5 mol or less, more preferably 2.0 mol or less.

  The temperature of the reaction solution is preferably maintained within the range of 0 ° C. to 50 ° C., more preferably 10 ° C. until the start of supplying chlorine after mixing the chloro higher-order alkanes and anhydrous aluminum chloride. To 40 ° C. The timing of starting the supply of chlorine is introduced by introducing the chloro higher alkanes represented by the formula (3) used in the reactor and the total amount of dehydrochlorination, preferably the aluminum chloride is dissolved, and further the formula (4) It is preferable to start supplying chlorine into the reactor after the chloro higher alkene represented by

  It is possible to carry out the production method of the present invention with higher selectivity by setting the concentration of the dehydrochlorination catalyst in the reaction system within the above range and adjusting the timing for starting the supply of chlorine and the supply rate to an appropriate range. it can. Specifically, the start of the supply of chlorine is a chloro higher-order alkene represented by the formula (4) by dehydrochlorination reaction (if the raw material is 1,1,1,3-tetrachloropropane, 1,1,3 -Trichloropropene) concentration is preferably 0.1 wt% to 30 wt%, more preferably 0.5 wt% to 20 wt%. The conversion rate of chloro higher alkanes represented by formula (3) is analyzed by gas chromatography, the total amount of hydrogen chloride discharged to the gas phase, or the temperature change of the reaction solution when the heat removal amount is constant, etc. Therefore, the concentration in the reaction system can be easily grasped from the conversion rate and the amount of supplied chlorine.

  As for the chlorine supply method, the whole amount may be supplied at a time (introduced into the reactor) at first, but in this case, side reactions are likely to occur, so it takes a certain amount of time as the dehydrochlorination reaction proceeds. It is preferable to supply gradually. The supply time is generally 0.5 to 20 hours, preferably about 1 to 10 hours, although it depends on the amount of raw material charged, the reaction temperature, the size of the reactor, and the like. Moreover, when supplying over time, you may supply continuously and may supply intermittently.

  More preferably, the proportion of the chloro higher-order alkene represented by the formula (4) in the reaction system is preferably 30 wt% or less, more preferably 20 wt% or less, and even more preferably 10 wt% or less. Adjust the chlorine supply rate. Further, it is preferable to adjust the chlorine supply rate so that the chlorine concentration in the reaction system is preferably 10 wt% or less, more preferably 5 wt% or less, further preferably 3 wt% or less, and particularly preferably 1 wt% or less.

  Although the optimal chlorine supply amount for maintaining the concentration in the reaction system of the chloro higher-order alkenes and chlorine represented by the above formula (4) varies depending on each temperature, the initial temperature is 0 to 50 ° C. The amount is preferably 1 to 2000 ml / min, more preferably 5 to 1000 ml / min, and still more preferably 10 to 500 ml / min with respect to 1 mol of chloropropane serving as a raw material charged into 1. Furthermore, in order to set the chlorine concentration in the reaction system within the above range, it is also preferable to change the flow rate in the above range during the reaction.

  For example, anhydrous aluminum chloride requires time until it is dissolved in the chloro higher-order alkanes represented by the formula (3), so the concentration of aluminum chloride is low at the beginning of the reaction, and the dehydrochlorination reaction is delayed. Therefore, it is preferable that the chlorine supply amount is small in the initial stage and the supply amount is increased in the middle of the reaction. On the other hand, the ratio of higher-order chloroalkanes decreased in the latter stage of the reaction. However, if the chlorine concentration is high in this state, the substitution of chlorine in the higher-order chlorohigher alkanes represented by the formula (5) further progresses. Therefore, it is preferable to reduce the supply amount of chlorine.

  For these reasons, after starting the supply of chlorine, the amount of chlorine supply is increased when the chloro higher-order alkanes as raw materials are preferably 95 wt% or less, more preferably 90 wt% or less, and the intended reaction proceeds. A method of reducing the supply amount of chlorine can be suitably employed when the concentration of the higher-order chloroalkanes, which are raw materials in the reaction system, is 30 wt% or less, more preferably 20 wt% or less.

  When introducing chlorine into the reactor, it may be introduced into the gas phase portion in the reactor, or may be carried out by inserting an introduction tube into the reaction solution and blowing it into the reaction solution.

  In the second reaction of the present invention, when the dechlorination reaction and the chlorination reaction are carried out simultaneously, it may be carried out by a batch reaction, or the chloro higher-order alkane represented by the formula (3) as a raw material is continuously used. It is also possible to carry out a continuous reaction in which the higher-order chloro higher-order alkanes represented by the formula (5) are continuously extracted while being fed to the reactor. In this case, since the dehydrochlorination catalyst is also taken out, it is preferable to additionally supply the dehydrochlorination catalyst in the reaction system so that it falls within the above range. When the continuous reaction is carried out, the supply amount of the chloro higher-order alkane represented by the formula (3) is preferably 0.1 to 1 per hour, where the average amount of liquid per hour in the reactor is 1. More preferably, 0.2 to 0.7 is supplied.

  The specific gravity may change when chloro higher alkanes react and become higher chloro higher alkanes. Therefore, the amount of higher chloro higher alkanes extracted should be adjusted appropriately, and the amount of liquid in the reactor Is preferably constant. For example, 1.00 L (about 1430 g) of 1,1,1,3-tetrachloropropane is dehydrochlorinated and chlorinated with 1,1,1,2,3-pentachloropropane at a conversion rate of 50 ° C. and a selectivity of 100%. Then, the volume increases to about 1.13 L (about 1700 g).

  When introducing the entire amount of chlorine into the reactor at once, it is preferable to adjust the chlorine concentration in the liquid by blowing gas into the reaction liquid. The gas to be blown in is chloro higher-order alkanes represented by the formula (3), chloro higher-order alkenes represented by the formula (4), and higher-order chloro of the target product represented by the formula (5). Although it will not restrict | limit especially if it is a gas inactive with respect to higher-order alkane, For example, nitrogen and argon are used suitably.

  After introducing the total amount of chlorine into the reactor and holding it for about 0.1 to 2 hours as necessary, a substance acting as a Lewis base can be added to the Lewis acid catalyst, which is represented by the formula (5). It is possible to prevent the dehydrochlorination reaction of higher chloro higher alkanes. Any known compound that acts as a Lewis base can be used without particular limitation. For example, water, alcohol compounds, carbonyl compounds, nitrile compounds, phenol compounds and the like can be mentioned. Of these, alcohol compounds, carbonyl compounds, nitrile compounds, and phenol compounds are preferable in consideration of corrosion of the reactor.

  Specific examples of the phenol compound include phenol and cresol (ortho, meta, para). Phenol compounds substituted with an allyl group can also be suitably used. Specific examples include o-allylphenol, m-allylphenol, p-allylphenol, 4-allyl-2-methoxyphenol (eugenol), 2- And methoxy-4- (1-propenyl) phenol (isoeugenol).

  Only one of these compounds may be used, or two or more thereof may be used. The amount of the Lewis base added to the reaction system is not particularly limited as long as it is more than the amount capable of deactivating the used dehydrochlorination catalyst. Often only increases. As a measure of the amount added, it is preferably 50% to 300%, more preferably 80% to 150%, more preferably 80% to 150%, based on the amount of dehydrochlorination catalyst added to the chloro higher-order alkane represented by formula (3). Preferably 90% to 120% of the substance Lewis base is added.

  Of course, the higher-order chloro higher-order alkanes represented by the formula (5) are obtained by supplying chlorine into the reaction solution of the dehydrochlorination reaction of the purified chloro higher-order alkanes obtained by the aforementioned first reaction. In addition to the production by proceeding, only the dehydrochlorination reaction of the purified chloro higher-order alkanes may proceed, and the resulting chloro higher-order alkenes may be applied as a separate step for production.

  The high-order chloro high-order alkanes represented by the formula (5) thus obtained can be purified by a known method. In the case of purification by distillation, it is preferable to distill after adding a stabilizer in addition to the removal of anhydrous aluminum chloride in the same manner as in the distillation of the chloro higher alkene represented by the formula (4). . The stabilizer described above can also be used.

Unreacted chlorine can be recovered and used again as raw material chlorine for this reaction, or it can be refined and used as a raw material for other reactions.
(Regeneration of adsorbent)
In the present invention, the adsorbent used in the adsorption step can be regenerated by a known method and reused as an adsorbent.

  The adsorbent regeneration method can be a known method. For example, a polar solvent such as methanol or ethanol is passed through the adsorbent and the adsorbent is separated and removed, and then the adsorbent is dried. After water vapor is passed through the adsorbent and the adsorbent is separated and removed, the adsorbent is dried. A method, a method of heating an adsorbent and allowing gas to pass therethrough, and separating and removing the adsorbate, are mentioned. Among them, the method of heating the adsorbent and circulating the gas to separate and remove the adsorbate is simple in operation, less expensive, and further, the adsorbate is a chloro represented by the above formula (3). Alkanes and amides represented by formula (2) are preferred because they are easy to recover.

  In the method of heating the adsorbent and circulating the gas to separate and remove the adsorbate, the gas to be distributed is not particularly limited, but is represented by the chloroalkane represented by the formula (3) and the formula (2). The amide is preferably an inert gas, and industrially inexpensive air, nitrogen, argon or the like can be preferably used.

  The heating temperature of the adsorbent is not particularly limited, but if the temperature is high, hydrogen chloride is generated due to the decomposition of the chloro higher-order alkane represented by the formula (3), or the formula (3). Since decomposition of chloro higher-order alkanes and amides represented by formula (2) occurs and carbon remains in the adsorbent, the temperature is preferably 250 ° C. or lower, more preferably 200 ° C. or lower, 160 More preferably, the temperature is set to ° C. or lower. When the temperature is low, it takes time to separate the chloro higher-order alkanes represented by the formula (3) and the amides represented by the formula (2) from the adsorbent, which is not efficient. Therefore, the lower limit temperature is preferably 50 ° C. or higher, more preferably 100 ° C. or higher, and further preferably 130 ° C. or higher.

  On the other hand, when the adsorbate is separated at a temperature equal to or higher than the boiling point of the chloroalkane represented by the formula (3) and the amide represented by the formula (2) in the above temperature range, the efficiency is improved. It is preferable because it can be separated. When the boiling point is higher than the heating temperature, it is preferable to reduce the pressure to lower the boiling point than the heating temperature. The pressure at that time may be appropriately determined depending on the types of the chloroalkanes of the formula (3) and the amides of the formula (2), but is usually 1 to 90 kPa (abs), preferably in terms of an absolute pressure of 25 ° C. More preferably, the pressure is reduced to 5 to 20 kPa (abs). When the decomposition temperature of the chloroalkane represented by the formula (3) is low or when the difference between the boiling point of the chloroalkane represented by the formula (3) and the temperature at the time of regeneration is large, the temperature is adjusted in two steps. It can also be raised.

  For example, when the chloroalkane represented by the formula (3) is 1,1,1,3-tetrachloropropane, 1,1,1,3-tetrachloropropane and the above formula (10) at 10 kPa (abs) and 90 ° C. After removing a part of the amides represented by 2), it is preferable to remove the remaining amides at 10 kPa (abs) and 130 ° C. Thus, by performing in 2 steps, decomposition | disassembly of the chloroalkane represented by said Formula (3) can be prevented, and amides represented by said Formula (2) can be removed efficiently.

  During regeneration of the adsorbent, the chloroalkane represented by the formula (3) and the amide represented by the formula (2) separated from the adsorbent are recovered and represented by carbon tetrachloride and the formula (1). Returning to the reaction step with the alkenes or the distillation step of the reaction solution obtained from the reaction is preferable for improving the yield of the target product. During regeneration of the adsorbent, the chloroalkane represented by the formula (3) and the amide represented by the formula (2) are recovered in a gaseous state together with the gas to be circulated. By cooling this gas, the chloro higher alkanes represented by (3) and the amides represented by the formula (2) can be easily liquefied and stored in a tank or the like. The liquid mainly contains chloro higher-order alkanes represented by the formula (3) and amides represented by the formula (2). As a matter of course, the concentration of the amides represented by the formula (2) is higher than the concentration before feeding the adsorption tower, and the concentration contained in the chloro higher-order alkanes represented by the formula (3) after the first reaction. May be higher.

  Examples of the place where the liquid is returned include, for example, a reaction vessel that performs an addition reaction in the first reaction step, and a distillation column in the distillation step, or a reaction solution after the first reaction is supplied to the distillation column. The storage tank in the case where a storage tank for storing one end is provided before the storage is performed.

  By the said aspect, content of the amide represented by Formula (2) in the reaction liquid which has as a main component the chloroalkane represented by Formula (3) brought into a distillation tower in a distillation process increases. However, what is necessary is just to reduce content of the amide represented by Formula (2) to the above-mentioned range in this distillation process.

  When the chloroalkane represented by the formula (3) and the amide represented by the formula (2) separated and recovered from the adsorbent during the regeneration of the adsorbent are returned to the addition reaction in the first reaction step. The recovered amides can be reused as a catalyst.

  The adsorbent is regenerated, and the recovered chloroalkanes represented by formula (3) are returned to the previous step to obtain chloroalkanes represented by formula (3) obtained from the first reaction. Of these, as purified chloro higher-order alkanes, preferably 95% or more, more preferably 99% or more can be recovered, which is very useful in improving the yield of the final product.

  Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to these examples. The concentrations used in the examples are weight ratios.

Example 1
(First reaction: addition reaction process)
A SUS autoclave (with an internal volume of 1,500 mL) having a stirrer, an ethylene gas inlet and a gas outlet, an additional addition port of N, N-dimethylacetamide, and a liquid outlet was substituted with ethylene and filled with ethylene. An autoclave was charged with 1,560 g of carbon tetrachloride, 2.0 g of N, N-dimethylacetamide and 4.0 g of K100 (Coke reduced iron powder manufactured by JFE Steel Corporation), the temperature was set to 130 ° C., and the gas phase The addition reaction was started by supplying ethylene so that the total pressure of the mixture became 0.6 MPa (abs).

  From the point of time when the total pressure of the gas phase reached 0.6 MPa (abs) at 130 ° C., N, N-dimethylacetamide was continuously added at 0.02 ml / min until the end of the reaction. During the reaction, ethylene is supplied so that the total pressure in the gas phase is maintained at 0.6 MPa (abs), and the ethylene consumption rate (additional supply rate) is 0.05 to the initial amount of carbon tetrachloride. The addition reaction of the first batch was completed when it was judged that the reaction was completed when the mol% / min (100 ml / min) was reached. The reaction time was 1000 minutes, the amount of N, N-dimethylacetamide used was about 18 g, the conversion rate of carbon tetrachloride was 95%, and the selectivity for 1,1,1,3-tetrachloropropane was 94%.

(Distillation process)
The reaction was performed twice, and 2000 g of the extracted reaction solution was put into a 2 L flask, the pressure was set to 10 kPa (abs), and the column top temperature was about 87 ° C., and batch distillation was performed. The distillation column is a HELI PAC NO. What filled 2 to 90 cm in height was used. About 200 g of the initial fraction containing a large amount of low-boiling substances was extracted from the liquid condensed at the top of the column and then recovered in total to obtain about 1500 g of liquid. In this recovered solution, about 1,9,1,3-tetrachloropropane is about 99.5%, N, N-dimethylacetamide is about 0.024% (240 ppmw), tetrachloroethylene, hexachloroethane, 1,1,1, About 0.5% of other substances such as 3,3-pentachloropropane were contained.
(Adsorption process)
To 1000 g of 1,1,1,3-tetrachloropropane containing 240 ppmw of the obtained N, N-dimethylacetamide, 20 g of silica gel (FUSilicia CARiACT: average particle size 1.7 mm, average pore size 10 nm) was added, and the temperature was 25 ° C. And stirred for 12 hours. After 12 hours, the silica gel was removed by filtration to obtain 1,1,1,3-tetrachloropropane. The concentration of N, N-dimethylacetamide contained in 1,1,1,3-tetrachloropropane was 0.001% (10 ppmw).

(Dehydrochlorination reaction process)
182 g of 1,1,1,3-tetrachloropropane containing 10 ppmw of the obtained N, N-dimethylacetamide was placed in a 200 ml four-necked eggplant flask. 0.05 g of anhydrous aluminum chloride was added. The liquid temperature was set to 25 ° C. and stirred for 4 hours. 1,1,3-Trichloropropene was obtained at a conversion rate of 1,1,1,3-tetrachloropropane of 20% and a selectivity to 1,1,3-trichloropropene of 90%.

Example 2
In the same manner as in Example 1, an addition reaction step, a distillation step, and an adsorption step were performed, and 1,1,1,3-tetrachloropropane containing 10 ppmw of N, N-dimethylacetamide obtained from the adsorption step was converted into 2 L of 4 1820 g was put into a mouth-necked eggplant flask. Thereto was further added 0.5 g of anhydrous aluminum chloride. The liquid temperature was set to 25 ° C. and stirred for 10 minutes. After confirming that the solution turned blue and aluminum chloride began to dissolve, chlorine was allowed to flow at 2 L / min while maintaining the solution temperature at 25 ° C. After 1 hour 30 minutes, the flow rate of chlorine was reduced to 1 L / min. After another hour, the inflow of chlorine was stopped and nitrogen was circulated to expel chlorine and hydrogen chloride. The reaction solution was analyzed by gas chromatography (hereinafter abbreviated as GC). The conversion of 1,1,1,3-tetrachloropropane was 100%, and the selectivity to 1,1,1,2,3-pentachloropropane was 95% (yield 95%).

Example 3
In the same manner as in Example 1, an addition reaction step and a distillation step were performed, and 1,000 g of 1,1,1,3-tetrachloropropane containing 240 ppmw of N, N-dimethylacetamide obtained from the distillation step was added to zeolite (X type manufactured by Tosoh Corporation). (Globular: average particle size 1.8 mm) 20 g was added and stirred. After 12 hours, the zeolite was removed by filtration to obtain 1,1,1,3-tetrachloropropane. The concentration of N, N-dimethylacetamide contained in 1,1,1,3-tetrachloropropane was 0.0005% (5 ppmw).

Example 4
In the same manner as in Example 1, an addition reaction step and a distillation step were performed, and 1000 g of 1,1,1,3-tetrachloropropane containing 240 ppmw of N, N-dimethylacetamide obtained from the distillation step was added to 20 g of activated alumina (spherical). Was added and stirred. After 12 hours, activated alumina was removed by filtration to obtain 1,1,1,3-tetrachloropropane. The concentration of N, N-dimethylacetamide contained in 1,1,1,3-tetrachloropropane was 0.0015% (15 ppmw).

Example 5 (Regeneration of adsorbent)
50 g of silica gel (Fuji Silysia CARiACT: average particle diameter 1.7 mm, average pore diameter 10 nm) in a cylindrical jacket type column (glass) container with a 2 cm inner diameter and a height of 30 cm in a double tube structure. I put it in. The weight of the jacket type column was 474 g. A liquid at 25 ° C. was circulated outside the double tube so that the internal temperature became constant. In the same manner as in Example 1, an addition reaction step and a distillation step were performed, and 1,1,1,3-tetrachloropropane was contained at 11.6 g / min containing 240 ppmw of N, N-dimethylacetamide obtained from the distillation step. Feeded continuously from the bottom of the column. 1,1,1,3-tetrachloropropane which passed through the silica gel emerging from the top of the column was obtained. The concentration of N, N-dimethylacetamide in 1,1,1,3-tetrachloropropane coming out after 400 minutes was 0.002% (20 ppmw). The concentration of N, N-dimethylacetamide in 1,1,1,3-tetrachloropropane coming out after 500 minutes was 0.0045% (45 ppmw). The concentration of N, N-dimethylacetamide in 1,1,1,3-tetrachloropropane coming out after 700 minutes was 0.010% (100 ppmw). The supply of 1,1,1,3-tetrachloropropane was stopped, and 200 ml of nitrogen was supplied from the top of the column at a normal pressure for 1 hour to expel the liquid remaining in the column. The supply of nitrogen was stopped. The weight of the jacket type column was 549 g.

  A liquid at 160 ° C. was circulated outside the double tube so that the internal temperature became constant. 20 ml of nitrogen was supplied from the top of the column. The pressure was reduced with a pump from the bottom of the column to 10 kPa (abs). The connecting pipe connecting the pump and the column was cooled, and gaseous 1,1,1,3-tetrachloropropane, N, N-dimethylacetamide and the like were condensed and recovered as a liquid. After 8 hours, the liquid outside the double tube was cooled to room temperature and the supply of nitrogen was stopped. About 70 g of condensed liquid was obtained. The condensed liquid was 1,1,1,3-tetrachloropropane containing 2% (20000 ppmw) of N, N-dimethylacetamide.

  An addition reaction was carried out in the same manner as in Example 1, and 1,1,1,3-containing 2000 g of the reaction solution obtained from the addition reaction and 20000 ppmw of the condensed liquid, N, N-dimethylacetamide. Batch distillation was performed by putting 70 g of tetrachloropropane into a 2 L flask, setting the pressure at 10 kPa (abs). After extracting about 200 g of the first fraction containing a large amount of low-boiling substances, the gas coming to the top of the tower was cooled (top temperature of about 87 ° C.), and about 1560 g of liquid was recovered by condensation. In this recovered solution, about 1,9,1,3-tetrachloropropane is about 99.5%, N, N-dimethylacetamide is about 0.024% (240 ppmw), tetrachloroethylene, hexachloroethane, 1,1,1, About 0.5% of other substances such as 3,3-pentachloropropane were contained.

Comparative example 1 (dehydrochlorination process)
In the same manner as in Example 1, an addition reaction step and a distillation step were performed, and 182 g of 1,1,1,3-tetrachloropropane containing 240 ppmw of N, N-dimethylacetamide obtained from the distillation step was added to 200 ml of four-necked eggplant. Placed in flask. 0.05 g of anhydrous aluminum chloride was added. The liquid temperature was set to 25 ° C. and stirred for 4 hours. The conversion of 1,1,1,3-tetrachloropropane was 0%.

Comparative Example 2
In the same manner as in Example 1, the addition reaction step was performed twice, and 2000 g of 1,1,1,3-tetrachloropropane containing 1% (10000 ppmw) of the obtained N, N-dimethylacetamide was placed in a 2200 ml flask. 600 g of silica gel (Fuji Silysia CARiACT: average particle size 1.7 mm, average pore size 10 nm) was added and stirred. After 12 hours, the silica gel was removed by filtration to obtain 1,1,1,3-tetrachloropropane. The concentration of N, N-dimethylacetamide contained in 1,1,1,3-tetrachloropropane was 0.02% (200 ppmw).
The concentration of the obtained N, N-dimethylacetamide was charged with 2000 g of 1,1,1,3-tetrachloropropane containing 200 ppmw in a 2 L flask, the pressure was set to 10 kPa (abs), and the top temperature was about 87 ° C. Batch distillation was performed. A distillation column similar to that in Example 1 was used. About 200 g of the initial fraction containing a large amount of low-boiling substances was extracted from the liquid condensed at the top of the column and then recovered in total to obtain about 1500 g of liquid. In this recovered liquid, about 1,9,1,3-tetrachloropropane was about 99.5%, N, N-dimethylacetamide was about 0.021% (210 ppmw), tetrachloroethylene, hexachloroethane, 1,1,1, About 0.5% of other substances such as 3,3-pentachloropropane were contained.
182 g of 1,1,1,3-tetrachloropropane containing 210 ppmw of the obtained N, N-dimethylacetamide was placed in a 200 ml four-necked eggplant flask. 0.05 g of anhydrous aluminum chloride was added. The liquid temperature was set to 25 ° C. and stirred for 4 hours. The conversion of 1,1,1,3-tetrachloropropane was 0%.

Reference Example (Synthesis of 1,1,1,3-tetrachloropropane using triethyl phosphate)
(Addition reaction process)
A SUS autoclave (with an internal volume of 1,500 mL) having a stirrer, a gas inlet for ethylene and a gas outlet, an additional addition port of phosphate ester, and a liquid outlet was subjected to an ethylene replacement operation and filled with ethylene. An autoclave was charged with 1,560 g of carbon tetrachloride, 2.0 g of triethyl phosphate and 4.0 g of K100 (Coke reduced iron powder manufactured by JFE Steel Co., Ltd.), the temperature was set to 110 ° C., and the total pressure in the gas phase was Addition reaction was started by supplying ethylene to 0.5 MPa (abs). From the time when the total pressure in the gas phase reached 110 ° C. and 0.5 MPa (abs), triethyl phosphate was continuously added at 0.02 ml / min until the end of the reaction. During the reaction, ethylene is supplied so that the total pressure in the gas phase is maintained at 0.5 MPa (abs), and the ethylene consumption rate (additional supply rate) is 0.05 to the initial amount of carbon tetrachloride. The addition reaction of the first batch was completed when it was judged that the reaction was completed when the mol% / min (100 ml / min) was reached. The reaction time was 420 minutes, the amount of triethyl phosphate used was about 10 g, the carbon tetrachloride conversion rate was 95%, and the 1,1,1,3-tetrachloropropane selectivity was 96%.
(Distillation process)
The reaction was performed twice, and 2000 g of the extracted reaction solution was put into a 2 L flask, the pressure was set to 10 kPa (abs), and batch distillation was performed.
The pressure was set to 10 kPa (abs), and batch distillation was performed at a column top temperature of about 87 ° C. A distillation column similar to that in Example 1 was used. About 200 g of the initial fraction containing a large amount of low-boiling substances was extracted from the liquid condensed at the top of the column and then recovered in total to obtain about 1500 g of liquid. This operation was repeated once more.
In the obtained recovered liquid, 1,1,1,3-tetrachloropropane was about 99.5%, and other substances such as tetrachloroethylene, hexachloroethane, 1,1,1,3,3-pentachloropropane were about 0. The content of triethyl phosphate was 0.0001% (1 ppmw) or less.
(Dehydrochlorination reaction process)
1820 g of the recovered liquid obtained from the distillation step was placed in a 2 L 4-neck eggplant flask. Thereto was further added 0.5 g of anhydrous aluminum chloride, the liquid temperature was set to 25 ° C., and the mixture was stirred for 10 minutes. After confirming that the solution turned blue and aluminum chloride began to dissolve, chlorine was allowed to flow at 2 L / min while maintaining the solution temperature at 25 ° C. After 1 hour and 30 minutes, the flow rate of chlorine was reduced to 1 L / min. After another hour, the inflow of chlorine was stopped and nitrogen was circulated to expel chlorine and hydrogen chloride. The reaction solution was analyzed by gas chromatography (hereinafter abbreviated as GC). The conversion of 1,1,1,3-tetrachloropropane was 100%, and the selectivity to 1,1,1,2,3-pentachloropropane was 95% (yield 95%).

Claims (10)

Carbon tetrachloride and the following general formula (1)
C _a H _b Cl _c (1)
(In Formula (1), a is an integer of 2-4, b is an integer of 1-2a, and c is an integer of 0-2a-1, provided that b + c is 2a.)
An alkene represented by the following general formula (2)
R ₁ C (═O) NR ₂ R ₃ (2)
(In Formula (2), R _1, R _{2 and} R ₃ are each H or a lower alkyl group having 1 to 3 carbon atoms , and may be the same or different)
In the presence of iron represented by the following general formula (3)
C _{a + 1} H _b Cl _{c + 4 (3)}
(In formula (3), a, b, and c are as described in formula (1).)
And then distilling the reaction solution, and then distilling the reaction solution, and then distillate fraction containing chloro higher-order alkane represented by formula (3) as a main component. In contact with the adsorbent,
Further, the purified chloro higher-order alkanes obtained were subjected to dehydrochlorination reaction, and the general formula (4)
C _{a + 1} H _b-1 Cl _{c + 3 (4)}
(In formula (4), a, b, and c are as described in formula (1).)
A process for producing a chloro higher alkene represented by the formula:   2. The method for producing chloro higher-order alkenes according to claim 1, wherein the adsorbent is silica gel or zeolite.   The distillation of the reaction solution containing the chloro higher alkanes represented by the above formula (3) is represented by the above formula (2) in the distillate fraction mainly composed of the chloro higher alkanes. The method for producing chloro higher-order alkenes according to claim 1 or 2, wherein the content of the amide is 100 to 1000 ppmw.   Contact with the adsorbent of the distillate fraction mainly composed of chloro higher alkanes represented by the above formula (3) obtained by distillation of the reaction liquid containing chloro higher alkanes. 4. The method according to claim 1, wherein the content of the amide represented by the formula (2) contained in the higher chloroalkane represented by the formula (3) is 50 ppmw or less. The manufacturing method of chloro higher alkene as described in claim | item. For the adsorbent after being brought into contact with the distillate fraction mainly composed of the chloro higher-order alkanes represented by the above formula (3), the adsorbent is desorbed,
A mixture of the recovered amides represented by the above formula (2) and higher chloroalkanes represented by the above formula (3) is converted to carbon tetrachloride and alkenes represented by the above formula (1). The method for producing a higher-order chloroalkene according to any one of claims 1 to 4, wherein the reaction solution is re-supplied to the reaction step or the distillation step of the reaction liquid obtained from the reaction.   The method for producing a chloro higher alkene according to any one of claims 1 to 5, wherein the amide represented by the formula (2) is N, N-dimethylacetamide.   The method for producing a chloro higher-order alkene according to any one of claims 1 to 6, wherein the dehydrochlorination reaction of the purified chloro higher-order alkane is performed in the presence of anhydrous aluminum chloride.   The alkene represented by the general formula (1) is ethylene, the chloro higher-order alkane represented by the general formula (3) is 1,1,1,3-tetrachloropropane, and the general formula (4) The method for producing a chloro higher alkene according to any one of claims 1 to 7, wherein 1,1,3-trichloro-1-propene is produced as the chloro higher alkene represented.   The alkenes represented by the general formula (1) are vinyl chloride, the chloro higher alkanes represented by the general formula (3) are 1,1,1,3,3-pentachloropropane, and the general formula ( The method for producing a chloro higher alkene according to any one of claims 1 to 7, wherein 1,1,3,3-tetrachloro-1-propene is produced as the chloro higher alkene represented by 4). In the manufacturing method of chloro higher alkenes as described in any one of Claims 1-9, chlorine is supplied in the reaction liquid of the dehydrochlorination reaction of refined chloro higher alkanes, and the chloro higher alkene produced | generated was produced | generated. Higher order chlorination reaction of alkenes is also proceeded in order to obtain general formula (5)
C _{a + 1} H _b-1 Cl _{c + 5 (5)}
(In Formula (5), a, b, and c are as described in Formula (1).)
A method for producing a higher-order chloro higher-order alkane, characterized in that a higher-order chloro higher-order alkane represented by the formula: