JPH023774B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for producing cumene and/or polyisopropylbenzene, more specifically, an alkylation reaction and a transalkylation reaction using benzene and propylene as starting materials in the presence of a Friedel-Crafts catalyst containing aluminum chloride as an essential component. The present invention relates to a method for producing cumene and/or polyisopropylbenzene. Benzene and propylene are reacted in the alkylation reaction step () in the presence of a Friedel-Crafts catalyst containing aluminum chloride as an essential component,
The reaction products mainly composed of cumene, diisopropylbenzene, triisopropylbenzene and unreacted benzene produced in this alkylation reaction step () are recycled from the distillation process to polyisopropylbenzenes such as diisopropylbenzene and triisopropylbenzene. At the same time, transalkylation is carried out in the transalkylation reaction step () in the presence of a Friedel-Crafts catalyst containing aluminum chloride as an essential component, and the product of the transalkylation reaction step is then distilled into a cumene fraction and other distillates. fraction to obtain, for example, cumene and/or the desired polyisopropylbenzene as a product, while other fractions, such as the benzene fraction, which are not obtained as a product, are subjected to an alkylation reaction step () and/or transalkylation. to the reaction step (), and diisopropylbenzene,
Transalkylation reaction process of polyisopropylbenzene such as triisopropylbenzene ()
The method for producing cumene and/or polyisopropylbenzene that is recycled to the plant is well known and can produce the desired products in good yields. For example, such a manufacturing method is specifically described in Japanese Patent Publication No. 32-7069. This method uses m-diisopropylbenzene, p-diisopropylbenzene,
It can be suitably used when polyisopropylbenzene such as triisopropylbenzene is produced alone or in combination. When cumene and/or polyisopropylbenzene is produced industrially by combining such an alkylation reaction step and a transalkylation reaction step and using aluminum chloride as a catalyst, the alkylation reaction step and the transalkylation reaction step are combined. A generally adopted method is to recover the Friedel-Crafts catalyst used in the reaction step and reuse it in both of the above steps. This is because we want to keep the cost of the catalyst as low as possible, and furthermore, when aluminum chloride is used as a catalyst in the above reaction, aluminum chloride reacts with aromatic hydrocarbons to form a complex oily complex. Since this complex has a high specific gravity and forms a phase separate from the starting material benzene and the product aromatic hydrocarbon phase such as cumene and polyisopropylbenzene, the complex having catalytic activity can be separated from the reaction products. It is used for various purposes. It is generally known that the catalytic activity of the complex decreases over time, and the present inventor also conducted the transalkylation reaction step by directly using the complex used in the alkylation reaction step together with the alkylation reaction product. Attempts have been made to repeatedly use the complex by separating the complex from the reaction product of the transalkylation reaction step and circulating it again to the alkylation reaction step, but the alkylation reaction and transalkylation reaction In both cases, it was confirmed that repeated use of the catalyst decreased the catalytic activity. On the other hand, it is generally known that when producing cumene and/or polyisopropylbenzene by combining the alkylation reaction step and the transalkylation reaction step, there is a problem in that ethylbenzene and trimethylindane are produced as by-products. It is as it is. A large amount of ethylbenzene by-product has a boiling point relatively close to that of cumene, so a special distillation column is required to remove ethylbenzene in order to obtain high purity cumene. In addition, since the boiling point of m-diisopropylbenzene and trimethylindane as a by-product are very close to each other, it is industrially impossible to separate the two by distillation.If you want to co-produce m-diisopropylbenzene, The purity of m-diisopropylbenzene decreases. The present inventors have carried out intensive research to solve the problems of the conventional method of producing cumene and/or polyisopropylbenzene from benzene and propylene as described above, and as a result, they have discovered that the by-product isopropyl trimethyl indane and the higher boiling point By separating the by-products from the triisopropylbenzene fraction by distillation and removing them from the system, the polyisopropylbenzene that is not desired to be obtained as a product is recycled to the transalkylation reaction process, thereby reducing the catalyst used. The present invention has been made based on the discovery that the degree of decrease in the activity of cumene and/or polyisopropylbenzene can be produced with high purity at a relatively low reaction temperature and a relatively high reaction rate. I've reached it. According to the present invention, () an alkylation reaction step of reacting benzene and propylene in the presence of a Friedel-Crafts catalyst containing aluminum chloride as an essential component; () a Friedel-Crafts catalyst containing aluminum chloride as an essential component; Production of cumene and/or polyisopropylbenzene, comprising a reaction step of transalkylating the product of the above-mentioned alkylation reaction step () in the presence of The method includes separating isopropyl trimethyl indane by-produced in the trans-alkylation step from polyisopropylbenzene by distillation, and then converting the polyisopropylbenzene that is not obtained as a product from the polyisopropylbenzene into the alkylation reaction step () and/or the trans-alkylation step. A method is provided for producing cumene and/or polyisopropylbenzene with circulation to the alkylation reaction step (). Hereinafter, the method of the present invention will be explained in more detail with reference to the accompanying drawings. Figure 1 shows cumene and p-diisopropylbenzene (hereinafter simply P) in the method for producing cumene and/or polyisopropylbenzene according to the present invention.
- DIPB) is a float chart for co-production. Hereinafter, the method of the present invention will be specifically explained with reference to FIG. 1, but it goes without saying that the scope of the present invention is not limited to the embodiment shown in FIG. It goes without saying that any polyisopropylbenzene can also be produced. According to the present invention, the catalyst containing aluminum chloride as an essential component used in the alkylation reaction step () and the transalkylation reaction step () is a common catalyst conventionally used in such reactions, such as Approximately 0.3 to 2 parts of hydrogen chloride as cocatalyst per 1 mole part of aluminum trichloride
Catalysts produced from molar parts and aromatic hydrocarbons such as benzene and cumene can be suitably used. When aluminum trichloride, hydrogen chloride, and aromatic hydrocarbons come into contact, they react with each other to form a high-density, oily complex with a complex structure, which is distinct from the low-density aromatic hydrocarbon phase. form another phase. This complex then acts as a Friedel-Crafts catalyst for the alkylation reaction. Therefore, in the alkylation reaction step () and the transalkylation reaction step (), the above-mentioned composite phase and the aromatic hydrocarbon phase come into contact and the alkylation reaction and the transalkylation reaction proceed. In the industrial implementation of steps () and (), a method of recycling the composite catalyst as described below is generally adopted. For example, a high specific gravity complex phase is separated from the reaction mixture of each of steps () and (), and the separated complex phase is recycled to steps () and (). In addition, the complex phase is directly supplied to the step () without being separated from the reaction mixture in the step (), a separation operation is performed on the reaction mixture from the step (), and the complex phase thus separated is transferred to the step (). ) and/or a method of recycling to step () can also be suitably used. When the composite is circulated and used in this way, the degree of decrease in catalyst activity is significantly smaller than in conventional methods, but it still decreases slightly, so some of the circulating composite is extracted from the system and a new one is used. It is necessary to carry out the operation with the addition of, for example, aluminum trichloride and hydrogen chloride as a co-catalyst. Additional addition of these compounds can be done, for example, in steps () and ().
or added to the reaction tank or circulation line of the complex,
Separately, a composite may be produced from an aromatic hydrocarbon such as benzene, cumene, diisopropylbenzene, triisopropylbenzene, etc. and the above compound and supplied to the reaction tank, circulation line, etc. In the alkylation reaction step () according to the present invention, benzene and propylene are reacted in the presence of the Friedel-Crafts catalyst described above. Benzene 11 supplied from outside the system and benzene fraction 12 recycled from within the system are first dehydrated in a dehydration tower 1, and the dehydrated benzene 13 is supplied to an alkyrator 2. On the other hand, propylene 14 and a composite catalyst 15 which is circulated within the system are also supplied to the alkyrator 2, and an alkylation reaction is carried out. In the alkylation reaction step (), the composite catalyst is generally supplied in an amount of about 0.1 to 30 parts by weight, preferably 0.3 to 5 parts by weight, based on 100 parts by weight of benzene. On the other hand, the amount of propylene supplied to step () varies depending on the target product to be manufactured, but generally the molar ratio of propylene to benzene (propylene/benzene) is approximately 0.05 to 1.5.
Preferably it is about 0.2 to 1.2. The reactions in the alkylation reaction step are mainly as shown below. That is, in the alkylation reaction step, benzene and propylene first react to produce cumene, and this cumene further reacts with propylene according to the above reaction formula (2) to form m-diisopropylbenzene (m-DIPB). Or generate p-DIPB. Furthermore,
For example, m-DIPB reacts with propylene to produce 1,3,5-TIPB (triisopropylbenzene) or 1,2,4-TIPB, as shown in formula (3) above.
generate. The alkylation reaction step () is generally about 40~
The reaction is carried out at a reaction temperature of 100 DEG C., preferably from about 40 DEG to 80 DEG C., and generally at a reaction pressure of from atmospheric pressure to about 20 Kg/ ^cm.sup.2 G. Further, the alkylation reaction step () according to the present invention is preferably carried out in a continuous manner from an industrial perspective, and the residence time at that time is generally about 1 minute to about 3 hours, preferably about 5 minutes to about 3 hours. Approximately 1 hour. If the reaction temperature in the alkylation reaction step () is too low, there will be a problem that the reaction rate will decrease.Furthermore, since the reaction in which propylene is added to the benzene nucleus is exothermic, a large amount of A problem arises in that a refrigerant is required. On the other hand, if the reaction temperature is too high, the amount of by-products such as trimethylindane and ethylbenzene will increase, and side reactions such as dimerization and trimerization of propylene will occur, producing by-products such as nonane and nonene that are difficult to separate from cumene. This is not preferable because it causes the problem of In the embodiment shown in FIG. 1, the polyisopropylbenzene fraction 16 such as diisopropylbenzene and triisopropylbenzene is recycled to the transalkyrator 3, but this polyisopropylbenzene fraction 16 is transferred to the alkylation reaction step (). It can also be cycled. Next, the reaction product of alkyrator 2 is fed to transalkyrator 3, where a transalkylation reaction is carried out. The reaction product of the alkylation reaction step may be separated from the composite catalyst contained therein before being supplied to the step (), but the entire reaction mixture is directly supplied to the step () without separation. The latter method is recommended industrially. As shown in FIG. 1, this transalkyrator 3 is also supplied with a circulating composite catalyst 15 and a polyisopropylbenzene fraction 16, where the following transalkylation reaction is carried out. Note that 17 is a new catalyst supply line. The amount of the composite catalyst used in the transalkylation reaction step () is generally about 0.2 to 100 parts by weight, preferably about 5 to 85 parts by weight, based on 100 parts by weight of the oil phase supplied to the step (). Department. In the transalkyrator 3, the following reactions (4) to (6) mainly occur. Although more complicated side reactions occur in the transalkyrator 3, the main reactions are as shown in reactions (7) to (9) below. In the above reaction formula, TMI is 1,1,3
- indicates trimethylindane, and IPTMI indicates isopropyltrimethylindane. The transalkylation reaction step () is generally carried out at a reaction temperature of about 30 to 100°C, preferably 40 to 80°C, and a pressure of atmospheric pressure to about 10 Kg/cm ² G, and is industrially carried out in a continuous manner. The residence time is generally from about 10 minutes to about 5 hours, preferably from about 20 minutes to about 4 hours. The composition of the reaction product of step () is
Although it depends on the reaction conditions and other conditions, in general, benzene is about 2 to 60% by weight, cumene is about 25 to 50% by weight, m-
DIPB about 2-40% by weight, p-DIPB about 1-22% by weight, triisopropylbenzene about 0.2-25% by weight
and other high boiling point compounds at about 3% by weight or less. The reaction product 18 thus generated is separated from the composite catalyst 15 in the catalyst separation tank 4,
After completely removing the catalyst components by alkali washing and water washing in the alkali washing tank 5, the catalyst is supplied to the distillation process (). The composite catalyst 15 separated in the catalyst separation tank 4 is recycled in the alkylation reaction step () and the transalkylation reaction step () as described above. In the distillation (fractional distillation) step ( ) in the method of the present invention, the reaction mixture from which the coexisting composite catalyst has been removed in the catalyst separation tank 4 and the alkali cleaning tank 5 is fractionated to separate it into each component. That is, the reaction mixture is first separated from the top of the benzene fraction 12 in the benzene fractionating column 6, and is recycled as a raw material for, for example, the alkylation reaction step (2) as described above. The bottom fraction 19 of the benzene fractionating column 6 is converted into the product cumene 20 and the bottom fraction 21 in the cumene fractionating column 7.
It is separated into This bottom fraction 21 is then m-
In the DIPB fractionating column 8, the top m-DIPB fraction 22
and a column bottom component 23. As described above, the overhead fraction 22 is recycled to the transalkyrator 3 as the polyisopropylbenzene fraction 16 in the illustrated embodiment. On the other hand, the bottom fraction 23 is p
-Product p-DIPB fraction 2 in DIPB fractionator 9
4 and a bottom fraction 25. This bottom fraction 2
5 separates isopropyltrimethylindane and other high-boiling substances 26 in a TIPB fractionation column 10, and collects a triisopropylbenzene fraction 27 from which isopropyltrimethylindane and other high-boiling substances have been removed from the top of the column. As mentioned above, it is recycled to the transalkyrator 3 together with the m-DIPB fraction. Distillation in the fractionating columns 6, 7, 8 and 9 can be carried out in the same manner as in conventional methods. However, according to the present invention, the TIPB fractionation column 10 is provided to remove isopropyltrimethylindane and other high-boiling substances from the triisopropylbenzene fraction to the transalkylation reaction step. Use cyclically in ().
The distillation method in this TIPB fractionation column 10 is such that the boiling point of triisopropylbenzene is 131°C/30mmHg, and the boiling point of isopropyltrimethylindane is 131°C/30mmHg.
137℃/30mmHg, and the vapor-liquid equilibrium relationship does not exhibit any special behavior.Thus, those skilled in the art will be able to determine the required number of distillation stages according to the desired degree of fractionation based on general distillation calculations. It can be fractionated. Generally speaking, in this fractional distillation step, at least 50% or more, preferably 60% or more of the isopropyltrimethylindane contained in the supplied raw material fraction 25 is removed from the system as the bottom fraction 26. Preferably, the distillation is carried out so that the In the embodiment of FIG. 1, cumene and p-DIPB
Although the embodiment of obtaining the above as a product has been described, it goes without saying that any other fraction can be obtained as a product. In addition, fractionator 6
It is not necessary to provide all of 10 to 10; for example, if the purpose is only to produce cumene, m
-DIPB fractionating column 8, p-DIPB fractionating column 9 and fractionating column 10 can be carried out in one column, and m
- If you want to produce only DIPB, m-DIPB can be obtained as a product in the fractionator 8, and the benzene fractionator 6, the cumene fractionator 7, and the fractionators 9 and 10 can be combined. . In any case, what is important in the present invention is to separate isopropyltrimethylindane and other high-boiling substances in the TIPB fractionation column 10 and remove them from the system to avoid recycling isopropyltrimethylindane. It is. As explained above, according to the method of the present invention, isopropyltrimethylindane (see reaction formula (8) above) produced as a by-product in the above-mentioned transalkylation reaction step () is removed from the system in the TIPB fractionation column 10. Therefore, a decrease in the activity of the composite catalyst due to isopropyltrimethylindane is avoided, and moreover, the trimethylindane produced in reaction formula (7) above shifts the equilibrium relationship in reaction formula (8) to the right, which is also a cause of catalyst activity decrease. The concentration of trimethylindane, which is a substance, decreases and indacene is produced by the reaction formula (9) (this is also a substance that causes a decrease in catalytic activity).
Since the amount of produced is reduced, a decrease in catalyst activity is further prevented. As described above, according to the present invention, the degree of decrease in catalyst activity is effectively reduced, making it possible to perform alkylation and transalkylation reactions at lower reaction temperatures than in conventional methods. By lowering the reaction temperature in this way, side reactions in each step are less likely to occur, and in particular, the amount of by-product ethylbenzene, an impurity during the production of cumene, is reduced, and p-DIPB and/or m-DIPB At the same time, the amount of by-product of the impurity trimethylindane during the production of is reduced, and at the same time, the degree of decrease in activity is further reduced. In this way, it is possible to produce highly pure cumene and/or diisopropylbenzene at a lower reaction temperature than in the conventional method, and to achieve the desired goal at a rather high reaction rate despite the lower reaction temperature compared to the conventional method. cumene and/
Alternatively, diisopropylbenzene can be produced. Hereinafter, the method of the present invention will be explained in more detail with reference to Examples, but it goes without saying that the scope of the present invention is not limited to these Examples. In addition, in the following examples, "%" indicates weight % unless otherwise specified. Example 1 and Comparative Example 1 In Example 1, cumene and p
- Operation was carried out to continuously produce DIPB. That is, benzene and a recycled benzene fraction are supplied to the dehydration tower 1 for dehydration, and the dehydrated benzene and propylene are supplied to the alkyrator 2 while circulating the catalyst (the amount of catalyst used is 100 parts by weight of benzene). The alkylation reaction was carried out using 2 parts by weight of the composite catalyst (aluminum trichloride and hydrogen chloride were replenished by the amount lost while being recycled according to the flow shown in FIG. 1). The alkylation reaction temperature was 70°C, and the reaction pressure was approximately normal pressure. The alkylation reaction product is recycled polyisopropyl fraction 16 (m-DIPB fractionation tower 8 and
It was supplied to the transalkyrator 3 together with the top fraction of the TIPB fractionating column 10, and transalkylated at a reaction temperature of 55° C. and a reaction pressure of approximately normal pressure. After removing the catalyst in a catalyst separation layer 4 and an alkali washing tank 5, the transalkylation reaction product is transferred to a benzene fractionation column 6, a cumene fractionation column 7, an m-DIPB fractionation column 8, and a p-DIPB fractionation column. 9 and TIPB fractionating column 10 in this order to obtain the product cumene (top fraction of cumene fractionating column 7) and the product p-diisopropylbenzene (top fraction of p-DIPB fractionating column 9). At the same time, the benzene fraction (the top fraction of the benzene fraction column 6) is circulated to the dehydration column 1, and the m-DIPB fraction (m-DIPB fraction) is recycled to the dehydration column 1.
The TIPB fraction (the top fraction of the TIPB fractionation column 10) was circulated in the transalkyrator 3 as the above-mentioned recycled polyisopropyl fraction. Column number Top pressure Bottom temperature 6 Normal pressure 168℃ 7 Normal pressure 220℃ 8 390mmHg 213℃ 9 250mmHg 213℃ As the TIPB fractionation column 10, a packed column with 45 theoretical plates was used, and the top pressure was 100mmHg, Tower bottom temperature 200
℃ and reflux ratio of 9 to obtain TIPB fraction 2 from the top of the column.
At the same time as 7 is distilled off, isopropyl trimethyl indane and other high boiling point substances 26 are distilled from the bottom of the column.
was taken out of the system. The system was operated continuously in this manner, and the material balance after 8 days from the start of operation is shown in Table 1. The purity of cumene is 99.9
% (ethylbenzene content 0.05%), p-DIPB purity was 99.1%.

[Table] On the other hand, in Comparative Example 1, the transalkyrator temperature was 65°C, the TIPB fractionating column 10 was operated using a 20-stage ripple tray, the top pressure was 50 mmHg, and the bottom temperature was 185°C. Continuous operation was carried out in the same manner as in Example 1 above, except that the operation was carried out at a temperature of 3° C. and a reflux ratio of 3. Table 2 shows the material balance 8 days after the start of operation. The purity of cumene was 99.8% (ethylbenzene content 0.15%), and the purity of p-DIPB was 97.5%.

【table】

[Table] As is clear from comparing the results of Example 1 and Comparative Example 1 above, in the method of the present invention,
In the TIPB fractionation column 10, isopropyltrimethylindane is substantially completely removed and discharged from the system, and the transalkylation reaction temperature is lowered to 55°C by removing isopropyltrimethylindane.
(compared to 65°C in the conventional example), the following practical effects can be obtained. 1. The purity of the product cumene is high. Example 1 Comparative Example 1 Cumene Purity (%) 99.9 99.8 Ethylbenzene Content (%) 0.05 0.15 2 The purity of the product p-diisopropylbenzene is high. Example 1 Comparative Example 1 Purity (%) 99.1 97.5 3 It is an energy-saving method because not only the production amount per unit time is large, but the amount of circulation from the distillation step to the alkylation and transalkylation steps is small. Example 1 Comparative Example 1 Cumene production (parts by weight/hour) 45.5 37.9 p-DIPB production (parts by weight/hour) 4.0 3.6 Circulating flow rate (1) (parts by weight/hour) 50 57.9 (1) Benzene fraction + m -DIPB fraction + TIPB fraction Furthermore, by referring to FIG. 2, the superiority of Example 1 over the comparative example will become clear.
In other words, the curve in Figure 2 is for benzene, cumene, m
The equilibrium composition (vertical axis) of -DIPB, p-DIPB and TIPB at about 50 to 80°C is plotted against the molar ratio of isopropyl group to benzene ring,
On the other hand, the composition in line 18 (that is, the outlet composition of transalkyrator 3) is shown at the base of the arrow in the case of the comparative example, and at the tip of the arrow in the case of the example. According to this, the composition in Example 1 is closer to the equilibrium composition, and the activity of the catalyst is higher than that of the comparative example. −DIPB,
It is clear that the concentration of TIPB is reduced and the energy required for their separation and circulation is considerably reduced. Example 2 From benzene and propylene to cumene and m-DIPB following a flow similar to that shown in Figure 1.
An operation was carried out to continuously co-produce p-DIPB and p-DIPB. That is, benzene and a recycled benzene fraction are supplied to the dehydration tower 1 for dehydration, and the dehydrated benzene and propylene are supplied to the alkyrator 2 while circulating the catalyst (the amount of catalyst used is 100 parts by weight of benzene). The alkylation reaction was carried out using 2 parts by weight of the composite catalyst (aluminum trichloride and hydrogen chloride were replenished by the amount lost while being recycled according to the flow shown in FIG. 1). The alkylation reaction temperature was 70°C, and the reaction pressure was approximately normal pressure. The alkylation reaction product, together with the circulating polyisopropyl fraction described below, is transferred to the transalkylation reactor 3.
The transalkylated reaction product was supplied to the reactor and transalkylated at a reaction temperature of 55°C and a reaction pressure of approximately normal pressure. , cumene fractionating column 7, m-DIPB fractionating column 8, p-DIPB fractionating column 9, a new fractionating column installed between fractionating column 8 and fractionating column 9 in FIG. (referred to as TMI fractionator)
And in the TIPB fractionating tower 10, fractional distillation is carried out in this order to produce product cumene (top fraction of cumene fractionating tower 7),
In addition to obtaining the product m-diisopropylbenzene (top fraction of m-DIPB fractionation column 8) and the product p-diisopropylbenzene (top fraction of p-DIPB fractionation column 9), a benzene fraction (benzene fractionation The top fraction of column 6) is circulated to dehydration column 1, and the top fraction of a new TMI fractionation column and the TIPB fraction (TIPB fractionation column 10) are recycled to dehydration column 1.
(top fraction) was recycled to the transalkyrator 3 as the above-mentioned recycled polyisopropyl fraction. The operation of each fractionating column was almost the same as in Example 1, except that the top pressure , bottom temperature, fractionating column 8, 250 mmHg, 190°C, TMI fractionating column, 390 mmHg, 207°C. As the TIPB separation column 10, a packed column with 45 theoretical plates was used, the top pressure was 100 mmHg, and the bottom temperature was 200 mmHg.
℃ and reflux ratio of 9 to obtain TIPB fraction 2 from the top of the column.
At the same time as 7 is distilled off, isopropyl trimethyl indane and other high boiling point substances 26 are distilled out from the bottom of the column.
was taken out of the system. The system was operated continuously in this manner, and the material balance after 8 days from the start of operation is shown in Table 3.

【table】

【table】 [Brief explanation of drawings]

FIG. 1 is a float chart for the co-production of cumene and p-diisopropylbenzene according to one embodiment of the process of the present invention, and FIG. 2 is a float chart of benzene, cumene, m-diisopropylbenzene, and 2 is a diagram showing the equilibrium compositions of p-diisopropylbenzene and triisopropylbenzene, and plots the transalkyrator outlet compositions of Example 1 and Comparative Example. 2... Alkyrator, 3... Transalkyrator, 4... Catalyst separation tank, 5... Alkali cleaning tank, 6... Benzene fractionator, 7... Cumene fractionator, 8... m-DIPB fraction Tower, 9...p-DIPB
Fractionating column, 10... TIPB fractionating column, 11... Benzene, 12... Circulating benzene fraction, 14... Propylene, 15... Composite catalyst, 16... Circulating polyisopropylbenzene, 20... Product cumene , 24
...Product p-diisopropylbenzene, 25...
Isopropyltrimethylindane and other high boilers.

Claims (1)

[Claims] 1 () An alkylation reaction step in which benzene and propylene are reacted in the presence of a Friedel-Crafts catalyst containing aluminum chloride as an essential component; () A Friedel-Crafts catalyst containing aluminum chloride as an essential component a reaction step of transalkylating the product of the above alkylation reaction step () in the presence of cumene and/or polyisopropylbenzene, and a step of fractionating the product of the transalkylation reaction step (). In the production method, after isopropyl trimethyl indane produced as a by-product in the transalkylation step is separated from polyisopropylbenzene by distillation, the polyisopropylbenzene that is not obtained as a product from the polyisopropylbenzene is separated from the polyisopropylbenzene that is not obtained as a product in the alkylation reaction step () and/or A method characterized in that cumene and/or polyisopropylbenzene is produced while being recycled to the transalkylation reaction step ().