JP2011046649A - Method for producing chloroalkane - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing a chloroalkane in a high conversion rate and in high selectivity by using compact production facilities in a short process time. <P>SOLUTION: In the method for producing a chloroalkane including performing a dehydrochlorination reaction of a compound represented by the formula C<SB>a</SB>H<SB>b</SB>Cl<SB>c</SB>(wherein a is an integer of 3-5; b and c are each independently an integer of 1 to 2a+1 with the proviso that b+c=2a+2; the carbon molecule chain is a straight chain) to give a reaction product and then performing a chlorination reaction of the reaction product to give a compound represented by the formula C<SB>a</SB>H<SB>b-1</SB>Cl<SB>c+1</SB>(wherein a, b and c are each as shown above), both the dehydrochlorination reaction and the chlorination reaction are carried out in a vapor phase and the reaction mixture after the dehydrochlorination reaction is directly supplied to the chlorination reaction. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a method for producing chloroalkane.

Chloroalkane is important as a raw material or intermediate for producing various products such as agricultural chemicals, pharmaceuticals, and CFC substitute materials. For example, 1,1,1,2,3-pentachloropropane is an important intermediate in the production of trichloroallyldiisopropylthiocarbamate useful as a herbicide.
As a typical method for producing a chloroalkane, carbon tetrachloride is added to an olefin or chloroolefin to form a first chloroalkane (first reaction), and then the first chloroalkane is dehydrochlorinated to alkene or A method is known in which a chloroalkene is converted (second reaction), and chlorine is further added to the alkene or chloroalkene to obtain a target chloroalkane (third reaction).
In such a three-stage reaction, the second reaction is carried out in the gas phase, the third reaction is carried out in the liquid phase (Patent Document 1), and the reaction product of the second reaction is subjected to distillation purification and is a byproduct, chlorination. It is common to remove hydrogen beforehand. For this reason, it is necessary to install a distillation tower and an intermediate tank between the reactor for the second reaction and the reactor for the third reaction, which requires a large production plant. Will be required. Furthermore, since the third reaction is performed in a liquid phase, it takes about 20 minutes to dissolve the reactants and catalyst to be used in the solvent, and the third reaction itself requires a reaction time of about one hour. Remarkably low.
A method for efficiently producing industrially useful chloroalkanes in a short process time using a compact production facility has not been known.

Japanese Examined Patent Publication No. 2-47969

  The present invention has been made in view of the above circumstances, and its purpose is to produce industrially useful chloroalkanes with high conversion and high selectivity in a short process time using compact manufacturing equipment. To provide a method.

According to the present invention, the above problem of the present invention is as follows.
The following general formula (1)
C _a H _b Cl _c (1)
(In formula (1), a is an integer of 3 to 5, b and c are each independently an integer of 1 to 2a + 1, provided that b + c = 2a + 2 and the chain of carbon molecules is linear. is there.)
A dehydrochlorination reaction of the compound represented by the formula (2), followed by a chlorination reaction of the reaction product, the following general formula (2)
C _a H _b-1 Cl _{c + 1} (2)
(In the formula (2), a, b and c have the same meanings as a, b and c in the general formula (1), respectively.)
In the method for producing a chloroalkane as a compound represented by
The dehydrochlorination reaction and the chlorination reaction are both carried out in the gas phase, and the reaction mixture after the dehydrochlorination reaction is directly subjected to the chlorination reaction.

  According to the present invention, industrially useful chloroalkanes can be shortened using a compact production facility that does not require a distillation column and an intermediate tank between the reactor for the second reaction and the reactor for the third reaction. The process time provides a method of efficiently producing with high conversion and high selectivity.

The method for producing a chloroalkane of the present invention comprises:
In the method for producing a chloroalkane, the dehydrochlorination reaction of the compound represented by the general formula (1) is performed, and then the chlorination reaction of the reaction product is performed to obtain the compound represented by the general formula (2). ,
Both the dehydrochlorination reaction and the chlorination reaction are carried out in the gas phase, and the reaction mixture after the dehydrochlorination reaction is directly subjected to the chlorination reaction.
Hereinafter, the present invention will be described in detail.

<Dehydrochlorination>
Specific examples of the compound represented by the general formula (1) used as a raw material in the method for producing chloroalkane of the present invention include:
Examples of the compound in which a in Formula (1) is 3 include 1,2-dichloropropane 1,1,1-trichloropropane, 1,1,1,3-tetrachloropropane, 1,1,1,2-tetrachloropropane, and the like. 1,1,1,3,3-pentachloropropane, 1,1,1,2,2-pentachloropropane, 1,1,1,2,3-pentachloropropane, 1,1,1,2,3, 3-hexachloropropane, 1,1,1,3,3,3-hexachloropropane, 1,1,1,2,3,3,3-heptachloropropane and the like;
Examples of the compound in which a is 4 include 1,1,1,2-tetrachlorobutane, 1,1,1,3-tetrachlorobutane, 1,1,1,4-tetrachlorobutane, 1,1,1. , 2,2-pentachlorobutane, 1,1,1,2,4-pentachlorobutane, 1,1,1,3,4-pentachlorobutane, 1,1,1,2,3,4-hexachloro Butane etc .;
Examples of the compound in which a is 5 include 1,1,1,2-tetrachloropentane, 1,1,1,3-tetrachloropentane, 1,1,1,4-tetrachloropentane, 1,1,1. , 5-tetrachloropentane, 1,1,1,2,3-pentachloropentane, 1,1,1,2,4-pentachloropentane, 1,1,1,2,5-pentachloropentane, 1,1,3,4-pentachloropentane, 1,1,1,4,5-pentachloropentane, 1,1,1,2,3,4-hexachloropentane, and the like.

As the compound represented by the general formula (1), among the above, a compound in which a in the formula (1) is 3 is preferable, and 1,2-dichloropropane or 1,1,1,3- is particularly preferable. Tetrachloropropane. Here, when 1,2-dichloropropane is used as the compound represented by the above formula (1), at least selected from the group consisting of 1-chloropropene, 2-prolopropene and 3-chloropropene as the dehydrochloride. Through one kind (preferably 3-chloropropene), 1,2,3-trichloropropane can be obtained as its chlorinated product. When 1,1,1,3-tetrachloropropane is used as the compound represented by the above formula (1), 1,1,3-trichloropropene and 3,3,3-trichloropropene are used as dehydrochlorides. Through at least one selected from the group consisting of (preferably 1,1,3-trichloropropene), 1,1,1,2,3-pentachloropropane can be obtained as the chlorinated product. These chloropropanes are industrially important as intermediates of various compounds and are particularly preferable.
Such a dehydrochlorination reaction of the compound represented by the general formula (1) is performed in a gas phase. This gas phase dehydrochlorination reaction is preferably a catalytic reaction or a thermal decomposition reaction. Hereinafter, the dehydrochlorination reaction of the compound represented by the general formula (1) will be described in order by dividing the reaction into a catalytic reaction and a thermal decomposition reaction.

[Dehydrochlorination reaction by catalytic reaction]
As the catalytic reaction, for example, a gas phase in which the compound represented by the general formula (1) is brought into contact with a crystalline phosphate mainly composed of crystalline aluminum phosphate as a catalyst in a non-oxidizing atmosphere. A catalytic reaction is preferred.
The crystalline phosphate mainly composed of crystalline aluminum phosphate can sufficiently exhibit a catalytic effect even if it is composed only of crystalline aluminum phosphate. Is preferably used as a complex in that a crystalline phosphate having a further improved catalytic action can be easily prepared. In this case, the proportion of aluminum ions in the crystalline phosphate with respect to the total number of aluminum ions and rare earth ions is preferably 80 mol% or more. The crystalline phosphate having such a composition can be represented by the following general formula (3).
αAlPO ₄ · (100-α) Ln (PO ₄ ) _x (3)
(In Formula (3), Ln is a rare earth ion, x is y / 3 (where y is the valence of the rare earth ion), and α is a number from 80 to 100.)
Ln in the general formula (3) is a rare earth ion. All rare earth ions generally have a trivalent valence. In exceptional cases, Eu, Yb and Sm can have a trivalent valence, and Ce, Tb and Pr can have a trivalent valence. In addition to the above, a tetravalent valence can be taken. As the crystalline phosphate used in the present invention, Ln in the above general formula (3) may be any of these, but is preferably a rare earth trivalent ion, and Ce or La A trivalent ion is preferable, and a trivalent ion of Ce is particularly preferable.
Α in the general formula (3) is a number of 80 to 100, preferably 80 to 95, and particularly preferably 85 to 95.

The crystalline phosphate preferably used in the present invention has crystallinity. This crystallinity can be confirmed by X-ray diffraction. That is, the crystalline phosphate used in the present invention shows sharp peaks at 2θ = 20.5 °, 21.6 ° and 23.2 ° in X-ray diffraction. Further, when the crystalline phosphate contains a rare earth crystalline phosphate, in addition to the above-mentioned peak in X-ray diffraction, it shows a peak derived from the rare earth crystalline phosphate. When the element is Ce, peaks at 2θ = 26.9 °, 28.8 °, and 31.1 ° are observed independently. From this, when the crystalline phosphate contains a rare earth crystalline phosphate, the crystalline phosphate has a portion of AlPO _{4 and} a portion of Ln (PO ₄ ) _x separately. It is inferred that they are mixed as crystals.
The preferred crystalline phosphoric acid used in the present invention, BET specific surface area measured by (Brunauer-Emmett-Teller) method as adsorbate nitrogen is preferably 10~400m ² / g, 20~400m ² / More preferably, it is g. By using a crystalline phosphate having a specific surface area in such a range of the catalyst, higher catalytic activity can be obtained, which is preferable.

A method for preparing such a crystalline phosphate is not particularly limited. For example, an aqueous solution containing aluminum nitrate and optionally a rare earth nitrate and phosphoric acid is prepared, and an appropriate alkali such as aqueous ammonia is added thereto. It is possible to use a method in which the precipitate formed by dripping and adjusting the pH of the aqueous solution to about 4 to 9 is recovered and thoroughly washed, and preferably dried and then fired. As the phosphoric acid content in the aqueous solution, it is preferable to add reaction equivalents to the aluminum atoms and rare earth atoms in the aqueous solution.
In the aqueous solution, the ratio of the total weight of components other than water to the total weight of the aqueous solution is preferably about 5 to 40% by weight. The drying can be performed, for example, by a heat treatment at a temperature of 80 to 150 ° C., preferably 100 to 130 ° C., for example, for 1 to 48 hours, preferably 4 to 24 hours. The ambient atmosphere during drying may be in the air. The dried body obtained after drying is preferably pulverized, classified or molded and then subjected to firing. The firing conditions are, for example, 500 to 1,500 ° C., preferably 600 to 1,400 ° C., more preferably 700 to 1,200 ° C., for example, 1 to 50 hours, preferably 2 to 24 hours. Can do. The ambient atmosphere during firing is preferably in the air.
Among the methods of the present invention, the shape of the crystalline phosphate preferably used for the dehydrochlorination reaction may be any shape, for example, powder, plate, column, cylinder, network, lump. Or any other shape.

In carrying out the dehydrochlorination reaction of the compound represented by the general formula (1), the compound represented by the general formula (1) is contacted with the crystalline phosphate as described above in a non-oxidizing atmosphere. Let
As long as this dehydrochlorination method reaction is carried out in the gas phase, any of a fixed bed flow method, a fluidized bed flow method, a fixed bed batch method, and a fluidized bed batch method may be used. When a salt is used, the reaction rate is excellent, and a high reaction conversion rate can be achieved in a short reaction time. Therefore, the fixed bed flow method or the fluidized bed flow method is preferable from the viewpoint of reaction efficiency.

As the feed gas supplied to the reactor in the dehydrochlorination reaction in the present invention, only the compound represented by the general formula (1) may be used, or together with the compound represented by the general formula (1). A dilution gas may be used.
In the dehydrochlorination method for the compound represented by the general formula (1), the concentration of the compound represented by the formula (1) in the supply gas supplied to the reactor is based on the total amount of the supply gas. It is preferably 10 mol% or more, more preferably 20 to 100 mol% or more, and further preferably 50 to 100 mol%. If this ratio is less than 10 mol%, it is economically disadvantageous. In general gas phase reactions, if the concentration of reactants in the supply gas is too high, the amount of unreacted substances will increase and the reaction efficiency will deteriorate, or the catalyst will deteriorate prematurely. Since the method using the crystalline phosphate in the present invention is excellent in reaction efficiency and the lifetime of the crystalline phosphate as a catalyst is extremely long, it is represented by the above formula (1) in the supply gas. It is possible to increase the concentration of the compound, for example without using any dilution gas.

As the diluent gas (component other than the compound represented by the above formula (1)) contained in the supply gas, it is preferable to use an inert gas, for example, nitrogen, argon, helium, etc. can be preferably used. However, it is particularly preferable to use nitrogen from the viewpoint of economical efficiency of the dilution gas. Since the gas phase dehydrochlorination reaction in the method of the present invention is performed in a non-oxidizing atmosphere, the oxygen concentration in the dilution gas is preferably adjusted to 1% or less. Further, if the product obtained by this dehydrochlorination reaction contains water, it is necessary to consider an extra purification step for the removal. In order to avoid this, it is preferable to adjust the water concentration in the dilution gas to 1,000 ppm or less.
Making the surrounding atmosphere in the contact of the compound represented by the general formula (1) and the crystalline phosphate non-oxidizing atmosphere does not use a dilution gas as a supply gas, or uses a dilution gas. Can be realized by using an inert gas having a low oxygen concentration as described above.
The feed gas is preferably preheated to a suitable temperature before being fed to the reactor. The preheating temperature is preferably 100 ° C. or higher, and more preferably 200 ° C. or higher. The upper limit of the preheating temperature is preferably (T + 100) ° C., more preferably (T + 50) ° C. when the reaction temperature described below is T ° C.
The reaction temperature of the dehydrochlorination method is preferably 200 to 500 ° C, more preferably 200 to 400 ° C. The residence time is preferably 0.5 to 10 seconds, and more preferably 0.5 to 5 seconds.
Furthermore, the space velocity (SV value, space velocity) in the dehydrochlorination method, that is, the amount of gas supplied per unit volume of the catalyst is preferably 300 to 10,000 hr ^−1, and preferably 700 to 10,000 hr ^−1. More preferably.

[When dehydrochlorination reaction is by thermal decomposition reaction]
On the other hand, in order to perform the dehydrochlorination reaction of the compound represented by the general formula (1) by a pyrolysis reaction, the compound represented by the formula (1) is heated at a temperature equal to or higher than the pyrolysis temperature. Can depend on the method.
As long as this pyrolysis reaction is carried out in the gas phase, any of a fixed bed flow method, a fluidized bed flow method, a fixed bed batch method, and a fluidized bed batch method may be used, but the method in the present invention is a high reaction with a short reaction time. Since the conversion rate can be achieved, the fixed bed flow method or the fluidized bed flow method is preferable from the viewpoint of reaction efficiency.
The heating temperature is preferably 300 to 600 ° C, more preferably 350 to 550 ° C. The heating time (residence time) should be appropriately selected depending on the kind of the compound represented by the general formula (1) and the heating temperature, and is preferably 1 to 10 seconds, for example, 1 to 5 seconds. It is more preferable to set it as 1 to 3 seconds. Here, if the heating temperature is less than 300 ° C. or the heating time is less than 1 second, thermal decomposition becomes difficult. On the other hand, if the heating temperature exceeds 600 ° C. or the heating time exceeds 10 seconds, the reaction selectivity May be low, both of which are not preferred. The dehydrochlorination reaction of 1,2-dichloroethane is generally carried out by a thermal decomposition method. In this case, a long heating time of about 70 seconds is generally required. However, in the present invention, the dehydrochlorination reaction can be carried out with an extremely short heating time as described above. This makes it possible to increase the selectivity of the target dehydrochloride.

As the supply gas supplied to the reactor in the thermal decomposition reaction, only the compound represented by the general formula (1) may be used, or a dilution gas may be used together with the compound represented by the general formula (1). May be used. The diluent gas that can be used here is the same as that described above as the diluent gas that can be used when the dehydrochlorination reaction is performed as a catalytic reaction. The concentration of the compound represented by the above formula (1) in the supply gas supplied to the reactor is preferably 20 mol% or more, more preferably 50 mol% or more, based on the total amount of the supply gas. Is more preferable. It is also possible to use no dilution gas at all.
It is preferable to cool the gas after the pyrolysis reaction promptly from the viewpoint of reducing by-products. Here, it is advantageous to cool the gas discharged from the pyrolysis reactor at the above pyrolysis temperature, preferably to a temperature below 350 ° C., more preferably below 300 ° C., preferably within 2 seconds. This cooling can be performed by a known method, for example, a heat exchange method with a supply gas, a method of spraying droplets of a dehydrochlorinated body and cooling with the latent heat of vaporization, or the like.

<Chlorination reaction of reaction product of dehydrochlorination>
The reaction mixture (exhaust gas from the reactor) of the dehydrochlorination reaction obtained as described above is directly used for the chlorination reaction in the next step. Here, it is one of the features of the method of the present invention that it is not particularly necessary to remove hydrogen chloride (HCl) from the exhaust gas as the reaction mixture. This eliminates the need to provide a distillation column and an intermediate tank between the dehydrochlorination reactor and the chlorination reactor, making it possible to design a chloroalkane production facility in a compact manner. .
Conventionally, when a chlorination reaction is carried out following a dehydrochlorination reaction of a chloroalkane, it has been usual to carry out the chlorination reaction after removing the hydrogen chloride produced by the dechlorination reaction by some method (for example, distillation). . This is because it was believed that if hydrogen chloride coexists during the chlorination reaction, it re-adds to the dehydrochloride and adversely affects the selectivity of the chlorination reaction. However, according to the study by the present inventors, even if hydrogen chloride coexists during the chlorination reaction, the chlorination reaction takes place preferentially by selecting certain reaction conditions, and the above-mentioned at a very high selectivity. The inventors have found that a chlorinated product represented by the general formula (2) can be obtained, and have reached the present invention.
Here, “the reaction mixture (exhaust gas) is subjected to the chlorination reaction as it is” means that the exhaust gas from the reactor of the dehydrochlorination reaction does not undergo any special purification (especially removal of hydrogen chloride) and has an outlet composition. This refers to the transfer to the reactor for the chlorination reaction in the next step, and it does not exclude the adjustment of the gas temperature after discharge or the addition of chlorine gas necessary for the chlorination reaction.

The chlorination reaction in the method of the present invention is carried out as a gas phase reaction. As long as this chlorination reaction is carried out in the gas phase, any of a fixed bed flow method, a fluid bed flow method, a fixed bed batch method, and a fluid bed batch method may be used, but the method in the present invention is a high reaction with a short reaction time. Since the conversion rate can be achieved, the fixed bed flow method or the fluidized bed flow method is preferable from the viewpoint of reaction efficiency.
The chlorination reaction in the method of the present invention can be carried out by heating a mixed gas of the exhaust gas of the dehydrochlorination reaction and the chlorine gas as described above at a predetermined temperature for a predetermined time.
The use ratio of the chlorine gas is preferably 0.9 to 2.0 mol, more preferably 1.0 to 1 mol with respect to 1 mol of the dehydrochloride contained in the reaction mixture of the dehydrochlorination reaction. 1.5 moles. If this value is less than 0.9 mol, the reaction conversion rate of the chlorination reaction may be impaired. On the other hand, if it exceeds 2.0 mol, there may be a disadvantage that the production of by-products increases. It is not preferable.
The reaction temperature of the chlorination reaction is preferably not less than the boiling point of the dehydrochloride and not more than 300 ° C., from the viewpoint of maintaining a gas phase state and suppressing the formation of by-products, and not less than the boiling point to 280 ° C. More preferably. The reaction time is preferably 1 to 60 seconds, more preferably 1 to 40 seconds.
This chlorination reaction is an exothermic reaction, and heat of reaction is generated as the reaction proceeds. Therefore, it is advantageous in terms of energy efficiency to perform heat exchange between the chlorination reaction system and the dehydrochlorination reaction system. That is, the dehydrochlorination reaction is preferably performed while supplying heat generated by the chlorination reaction.

<Chloroalkanes obtained by the method of the present invention>
The product obtained from the chlorination reactor as described above by the method of the present invention is a chloroalkane represented by the above general formula (2).
As the chloroalkane represented by the general formula (2), a compound obtained by dehydrochlorinating and then chlorinating the compound represented by the general formula (1) as a starting material can be obtained. Illustrative of typical products, when 1,1,1,3-tetrachloropropane, 1,1,1,2-tetrachloropropane or 1,2-dichloropropane is used as the starting material, 1,2,3-pentachloropropane, 1,1,1,2,2-pentachloropropane or 1,2,3-trichloropropane can be obtained, respectively.
In the examples described later, a method for producing 1,1,1,2,3-pentachloropropane using 1,1,1,3-tetrachloropropane as a starting material and 1,2-dibenzene as a starting material. Although only the method for producing 1,2,3-trichloropropane using chloropropane has been described, these methods can be similarly applied to other compounds as starting materials and exhibit the same effects. can do.
In addition to the hydrogen chloride produced by the dehydrochlorination reaction, the unreacted chlorine in the chlorination reaction and the dilution gas (when used), the gas discharged from the chlorination reactor is high in conversion and high in selection. Containing chloroalkanes converted to the desired product at a high rate. Therefore, the exhaust gas from the chlorination reactor according to the method of the present invention can be used as a product as it is if the hydrogen chloride, chlorine and diluent gas contained therein are separated. If desired, purification can be carried out thereafter. However, the purification method may be very simple. For example, a simple product having about 2 to 10 theoretical plates can be used to obtain a high-purity product.
The hydrogen chloride and chlorine separated as described above can be reused for other purposes after being purified by a conventional method.

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples.
<Preparation example of crystalline phosphate>
Preparation Example ₁ (Preparation of 90AlPO ₄ · 10CePO 4)
400 mL of pure water containing 55.4 g of Al (NO ₃ ) ₃ .9H ₂ O, 7.1 g of Ce (NO ₃ ) ₃ .6H ₂ O, and 18.9 g of 85 wt% phosphoric acid aqueous solution as the raw material aqueous solution Dissolved in. While stirring this with a mixer, 10% by weight aqueous ammonia was added dropwise over 2 hours until the pH of the solution reached 4.5. The precipitated 90AlPO ₄ · 10CePO ₄ was collected by filtration and repeatedly washed with water. The 90AlPO ₄ · 10CePO ₄ after washed with water, dried for 12 hours in a dryer controlled at 120 ° C., in air in an electric furnace at 1,000 ° C., was fired for 5 hours.
When X-ray diffraction analysis was performed on 90AlPO ₄ · 10CePO ₄ after firing, sharp peaks at 2θ = 20.5 °, 21.6 ° and 23.2 ° were confirmed, and this was crystalline. I understood. Further, sharp peaks derived from CePO ₄ crystals at 2θ = 26.9 °, 28.8 ° and 31.1 ° were also independently confirmed. Further, the specific surface area of this 90AlPO ₄ · 10CePO ₄ measured by BET method using nitrogen as an adsorbate was 73 m ² / g.

<Production example of chloroalkane>
In the following examples and reference examples, chloroalkane production tests were conducted using two reactors in which a dehydrochlorination reactor and a chlorination reactor were connected in series as described below.
(1) Dehydrochlorination step As a dehydrochlorination reactor, a SUS316 reaction tube having an inner diameter of 4.35 mm and a length of 300 mm was used. The inside of the reaction tube was used in a hollow state (Examples 1, 3 to 5 and Reference Example 1) or filled with a catalyst (Example 2). An electric furnace is disposed outside the reaction tube, and the reaction tube can be heated to a predetermined temperature.
The raw material compound whose flow rate is adjusted by the flow rate regulator so as to have a predetermined residence time is configured to be supplied as a gas to the reaction tube via a preheater set to a temperature of 200 ° C.
The dehydrochlorination reaction was performed at normal pressure.
The analysis of the exhaust gas from the reactor was performed by gas chromatography using a part of the exhaust gas taken 60 minutes after the start of the reaction, cooled to 0 ° C. and liquefied, as a sample.
(2) Chlorination step As the chlorination reactor, an SUS reaction tube having an inner diameter of 4.35 mm and a length of 300 mm was used. The inside of the reaction tube was used as it was hollow.
The exhaust gas from the dehydrochlorination reactor is adjusted by a cooler so that a temperature sensor inserted therein becomes a predetermined temperature, mixed with chlorine gas supplied through a flow controller, Fed to the reactor. The residence time in the chlorination reaction was set by adjusting the flow rate of chlorine gas.
The dechlorination reaction was performed at normal pressure.
The analysis of the exhaust gas from the reactor was performed by gas chromatography using a part of the exhaust gas taken 60 minutes after the start of the reaction, cooled to 0 ° C. and liquefied, as a sample. The selectivity at this stage shown in Table 1 is a value based on the intermediate trichloropropene.

Example 1
(1) Dehydrochlorination step 1,1,1,3-tetrachloropropane was used as a raw material compound, and a dehydrochlorination reaction was performed under the conditions of a residence time of 2.5 seconds and a reaction temperature of 500 ° C.
In this dehydrochlorination reaction, the reaction conversion rate was 99.7%, and the selectivity for 1,1,3-trichloropropene as the target compound was 99.0%.
(2) Chlorination process The exhaust gas from the above dehydrochlorination process is cooled to 150 ° C, mixed with the chlorine gas whose flow rate has been adjusted, supplied to the reactor, and subjected to a chlorination reaction under the condition of a residence time of 1.24 seconds. went.
In this chlorination reaction, the reaction conversion rate was 99.0%, and the selectivity for 1,1,1,2,3-pentachloropropane as the target compound was 95.0%.
Example 2
In the (1) dehydrochlorination step of Example 1 above, the reaction tube was prepared in Preparation Example 1 above, and then 1 g of 90AlPO ₄ · 10CePO ₄ was filled and dried at 400 ° C. for 2 hours under nitrogen flow. Thereafter, the reaction temperature was set to 300 ° C. and the residence time was set to 0.5 seconds. Otherwise, the dehydrochlorination reaction of 1,1,1,3-tetrachloropropane and the chlorination reaction in the same manner as in Example 1. Went.
The reaction results are shown in Table 1.

Example 3
In Example 1, except that 1,2-dichloropropane was used as the starting compound, a dehydrochlorination reaction and a chlorination reaction were performed in the same manner as in Example 1.
The reaction results are shown in Table 1. Here, (1) the target product in the dehydrochlorination step is 3-chloropropene, and (2) the target product in the chlorination step is 1,2,3-trichloropropane.
Example 4
In the (2) chlorination step of Example 1 above, the dehydrochlorination reaction of 1,1,1,3-tetrachloropropane was performed in the same manner as in Example 1 except that the residence time was 4.24 seconds, and Subsequently, a chlorination reaction was performed.
The reaction results are shown in Table 1.

Example 5
In the (2) chlorination step of Example 1, the reaction temperature (that is, the temperature after adjusting the temperature of the exhaust gas in (1) dehydrochlorination step) was set to 200 ° C., The dehydrochlorination reaction of 1,1,3-tetrachloropropane, followed by the chlorination reaction.
The reaction results are shown in Table 1.
Reference Example In Example 1 above, (1) The exhaust gas after the dehydrochlorination step was once cooled to the liquefaction temperature of 1,1,3-trichloropropene to separate and remove hydrogen chloride, and then (2) chlorination The same as in Example 1 except that the supply rate of chlorine gas was 360 NmL / min (0 ° C., 1 atm converted value), and the analysis of the exhaust gas from each reactor was performed 270 minutes after the start of the reaction. The dehydrochlorination reaction of 1,1,1,3-tetrachloropropane and the subsequent chlorination reaction are shown in Table 1. The residence time in this reference example was 2.5 seconds for the dehydrogenation reaction and 1.24 seconds for the chlorination reaction.
As can be easily understood from the results shown in Table 1, the method of the present invention in which the chlorination reaction is carried out as it is without removing the hydrogen chloride after the dehydrochlorination reaction is the conventional method for removing hydrogen chloride (the present method). Conversion and selectivity comparable to those of the Reference Example can be achieved at a lower cost in a shorter process time using a more compact production facility.

In addition, the abbreviation of the raw material compound in Table 1 has the following meaning, respectively.
PTC: 1,1,1,3-tetrachloropropane PDC: 1,2-dichloropropane

Claims (6)

The following general formula (1)
C _a H _b Cl _c (1)
(In formula (1), a is an integer of 3 to 5, b and c are each independently an integer of 1 to 2a + 1, provided that b + c = 2a + 2 and the chain of carbon molecules is linear. is there.)
A dehydrochlorination reaction of the compound represented by the formula (2), followed by a chlorination reaction of the reaction product, the following general formula (2)
C _a H _b-1 Cl _{c + 1} (2)
(In the formula (1), a, b and c have the same meanings as a, b and c in the general formula (1), respectively.)
In the method for producing a chloroalkane as a compound represented by
A method for producing a chloroalkane, characterized in that both the dehydrochlorination reaction and the chlorination reaction are carried out in the gas phase, and the reaction mixture after the dehydrochlorination reaction is directly subjected to the chlorination reaction.   The method for producing a chloroalkane according to claim 1, wherein the dehydrochlorination reaction is performed while supplying heat generated by the chlorination reaction.   The method for producing a chloroalkane according to claim 1 or 2, wherein a in the general formula (1) is 3.   The method for producing a chloroalkane according to claim 3, wherein the compound represented by the general formula (1) is 1,2-dichloropropane or 1,1,1,3-tetrachloropropane.   The dehydrochlorination reaction is performed by bringing the compound represented by the general formula (1) into contact with a crystalline phosphate mainly composed of crystalline aluminum phosphate in a non-oxidizing atmosphere. The manufacturing method of the chloroalkane as described in any one of Claims 1-4 which exists.   The method for producing a chloroalkane according to any one of claims 1 to 4, wherein the dehydrochlorination reaction is carried out by thermally decomposing the compound represented by the general formula (1).