JPH0326791A - Production of hydrocarbon - Google Patents

Abstract

PURPOSE:To efficiently obtain a hydrocarbon rich in benzene, toluene and xylene by blending a light hydrocarbon with a hydrocarbon containing a polycyclic and a monocyclic hydrocarbons and reacting in the presence of a zeolite- containing catalyst. CONSTITUTION:(A) 2-8C light hydrocarbon is blended with (B) 1-50wt.% (1-30wt.%) based on the total amounts of hydrocarbons of >=9C hydrocarbon containing 140wt.% aromatic hydrocarbon and >=3wt.% polycyclic aromatic hydrocarbon. Then the hydrocarbons are reacted in the presence of a catalyst containing a zeolite having >=1 CI value to give the aimed hydrocarbon. A catalyst containing a metal such as Cu, Ag, Zn, Cd, Ga, Cr, W, Se, Te, Re, Co, Ni, Pd, Ir and Pt may be cited as the catalyst.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a method for producing hydrocarbons enriched in BTX, and more specifically, the present invention relates to a method for producing hydrocarbons enriched in BTX, and more specifically, from light hydrocarbons having 2 to 8 carbon atoms to base materials for high octane gasoline and B is useful as a petrochemical raw material, etc.
TX, that is, a method for efficiently producing hydrocarbons rich in benzene, toluene, and xylene. [Prior Art] Naphtha containing light hydrocarbons, especially light naphtha, has few uses and is in surplus, so there is a need for efficient conversion technology to higher value-added BTX-containing hydrocarbons.
On the other hand, FCC (Fluid Catalytic Crafting) circulating oils such as LC○ (Light Cycle Oil), HCO (Heavy Cycle Oil), and CLO (Thalarified Oil), coal liquefied oil, heavy oil pyrolysis process raw oil, heavy oil Similarly, high added value is required for hydrocarbon fractions having 9 or more carbon atoms, such as oil hydrocracked products or oils.

As a conventional technique for producing BTX-containing hydrocarbons using light hydrocarbons having 2 to 8 carbon atoms and heavy hydrocarbons as reaction raw materials, (Japanese Patent Publication No. 56-42639), ■ A method using a mixture of naphtha and light oil as a reaction raw material and aiming at increasing the octane number of naphtha and lowering the pour point of light oil (US Patent No. 3893).
906 specification) and (2) a method using a mixture of an olefin having 2 or more carbon atoms and light oil as a reaction raw material (Japanese Unexamined Patent Publication No. 57
-144791) is known. However, in method (1) above, reaction heat (
There are problems such as a large amount of heat (endotherm) and it is relatively difficult to maintain the reaction temperature. Note that the publication (■) does not mention that a fraction with a high content of polycyclic aromatic hydrocarbons such as LCO is used as a reaction raw material component, and aromatic hydrocarbons do not substantially participate in the reaction under the conditions described in the publication. It is said that it is better to use less raw material because it does not have a negative impact on the raw material content. In the method (2) above, since light oil is used as the heavy hydrocarbon source, the aromatic hydrocarbon content in the raw bottom material is as low as about 15 to 30% by volume, and the heat of reaction (endotherm) is sufficiently reduced. There are problems such as it is difficult to say. Also, in the statement of ■, LCO
There is no mention of using a fraction with a high aromatic content having 9 or more carbon atoms as a raw material for the reaction.

In the method (2) above, by using an olefin, BT
Although the yield of X has been improved, since general light oil is used as the heavy hydrocarbon source, there are still problems such as the reduction of reaction heat (endotherm) is still not sufficient.

That is, the conventional techniques have various problems as described above, and it has been desired to develop a method for efficiently obtaining BTX-rich hydrocarbons from light hydrocarbons having 2 to 8 carbon atoms.

[Problem to be solved by the invention]

The present invention has been made in view of the above circumstances. An object of the present invention is to solve the above problems and provide a method for efficiently producing BTX-rich hydrocarbons from light hydrocarbons having 2 to 8 carbon atoms.

[Means for solving intelligence problems]

As a result of extensive research to solve the above-mentioned problems, the present inventors have succeeded in producing BT from light hydrocarbons having 2 to 8 carbon atoms using a catalyst containing a specific zeolite with a CI value of 1 or more.
In producing X-containing hydrocarbons, a reaction is carried out by adding a specific proportion of hydrocarbons having 9 or more carbon atoms each containing specific amounts of aromatic hydrocarbons and polycyclic aromatic hydrocarbons as reaction raw material components. It has been discovered that the above object can be satisfied, and based on this knowledge, the present invention has been completed.

That is, the present invention provides light hydrocarbons having 2 to 8 carbon atoms,
Hydrocarbons having 9 or more carbon atoms containing 40% by weight or more of aromatic hydrocarbons and 3% by weight or more of polycyclic aromatic hydrocarbons are added so that the addition ratio is 1 to 50% by weight of the total hydrocarbons. The present invention provides a method for producing BTX-rich hydrocarbons, characterized in that the reaction is carried out in the presence of a catalyst containing zeolite having a CI value of 1 or more. In the present invention, the hydrocarbons having 2 to 8 carbon atoms used as reaction raw materials include hydrocarbons having 2 to 8 carbon atoms (linear, branched or cyclic paraffins, olefins, dienes, etc.). and acetylenes, etc.), or a light hydrocarbon fraction containing them as a main component.

Note that this light hydrocarbon having 2 to 8 carbon atoms may contain a small amount of impurities such as monocyclic aromatics and methane within a range that does not interfere with the purpose of the present invention.

In the present invention, the specific hydrocarbon having 9 or more carbon atoms is supplied to the reaction system together with the light hydrocarbon having 2 to 8 carbon atoms and used as a reaction raw material.

This hydrocarbon having 9 or more carbon atoms contains 40% by weight or more of an aromatic hydrocarbon having 9 or more carbon atoms (monocyclic aromatic hydrocarbons and polycyclic aromatic hydrocarbons having 2 or more rings), and contains 2 or more rings. It contains 3% by weight or more of polycyclic aromatic hydrocarbons.

Specific examples of the monocyclic aromatic hydrocarbon having 9 or more carbon atoms include alkylbenzenes such as trimethylbenzene, tetramethylbenzene, pentamethylbenzene, hexamethylbenzene, ethylmethylbenzene, diethylbenzene, probylbenzene, and butylbenzene. , alkenylbenzenes such as methylvinylbenzene, propenylbenzene, butenylbenzene, and other benzene compounds having various hydrocarbon substituents. These may be contained singly or as a mixture of two or more.

In the present invention, the polycyclic aromatic hydrocarbon ring having two or more rings is an aromatic hydrocarbon ring having at least one ring and having at least one aromatic nucleus, even if these have no substituents. However, it is possible to have any of the following. Examples of the polycyclic aromatic hydrocarbon include substituted naphthalenes having one or more acyclic hydrocarbon groups as a substituent such as naphthalene, alkyl or alkenylnaphthalene, phenyls such as biphenyls, diphenylalkanes, and alkenes. benzenes having as a substituent a hydrocarbon group containing one non-aromatic cyclic hydrocarbon group such as an aromatic bicyclic hydrocarbon group having two groups or substituted phenyl groups, a cycloalkyl group, a cycloalkenyl group, etc. , or various 2-rings such as bicyclic aromatic hydrocarbons containing one benzene nucleus or substituted benzene nucleus and one non-aromatic hydrocarbon ring such as indenes, dihydronaphthalenes, and tetrahydronaphthalenes. Aromatic hydrocarbons, anthracene, substituted anthracenes having one or more acyclic hydrocarbon groups as a substituent, phenanthrene, 1 as a substituent
Substituted phenanthrenes having 1 or more acyclic hydrocarbon groups, tricyclic aromatic hydrocarbons having 1 or 2 benzene rings or substituted hanzene rings (including fluorene, substituted fluorene, etc.), or 1 or more acyclic hydrocarbon groups; Examples include various 3-ring aromatic hydrocarbons such as 3-ring aromatic hydrocarbons having a naphthalene ring or a substituted naphthalene ring. Among these, polycyclic aromatic hydrocarbons having two or more rings which are usually suitably used in the method of the present invention include naphthalene, alkylnaphthalenes such as methylnaphthalene, dimethylnaphthalene, trimethylnaphthalene, and ethylnaphthalenes, anthracene and methyl anthracene,
Alkylanthracenes such as dimethylanthracene,
Examples include alkylphenanthrenes such as phenanthrene and methylphenanthrene.

The polycyclic aromatic hydrocarbon having two or more rings may be contained alone or in a mixture of two or more.

In the method of the present invention, the content of the aromatic hydrocarbon having 9 or more carbon atoms in the hydrocarbon fraction having 9 or more carbon atoms used as a reaction raw material is less than 40% by weight, or The content of polycyclic aromatic hydrocarbons is 3
If it is less than % by weight, the exothermic effect in the reaction will be insufficient, and the endothermic amount of the endothermic reaction of the light hydrocarbon having 2 to 8 carbon atoms to be used will not be sufficiently compensated for, and the endothermic amount of the entire reaction system will be reduced. cannot be reduced. In the present invention, a mixture of at least the light hydrocarbon having 2 to 8 carbon atoms and the specific hydrocarbon having 9 or more carbon atoms is used as a reaction raw material, and this is supplied to the reaction system in the presence of the catalyst, The reaction produces hydrocarbons enriched in BTX. The proportion of the hydrocarbon fraction having 9 or more carbon atoms used at this time is 100% by weight of the total hydrocarbons (sometimes abbreviated as HC) supplied to the reaction system.
It is set within the range of 1 to 50% by weight, preferably within the range of 1 to 30% by weight. If this proportion is less than 1% by weight, the effect of reducing the amount of heat absorbed by the endothermic reaction cannot be obtained as described above,
On the other hand, if it exceeds 50% by weight, the endothermic amount of light hydrocarbons having 2 to 8 carbon atoms will decrease, but the process efficiency for the desired conversion reaction from light hydrocarbons having 2 to 8 carbon atoms to BTX etc. will be low. At the same time, the amount of BTX consumed decreases significantly, making it impossible to achieve the purpose of the present invention. In the method of the present invention, hydrocarbons having 9 or more carbon atoms that can be preferably used include, for example, FCCWI ring oils such as LCO, HCO, and CLO, coal liquefied oils, and heavy oil pyrolysis process oils. , heavy oil hydrocracked oil, etc. These can be used by mixing two types or adjusting the precepts and groups as desired. In addition, the hydrocarbons having 9 or more carbon atoms are those containing heteroatom-containing hydrocarbons containing sulfur, oxygen, nitrogen, etc., within a range that does not interfere with the purpose of the present invention. It's okay. In the method of the present invention, the reaction can be carried out in the presence of hydrogen (H.) or in its absence. Hydrogen (
H! ) is preferably within the range of O≦(H./HC)≦1 when expressed as a molar ratio to the total hydrocarbons (HC) to be supplied. If this ratio (molar ratio) exceeds 1, excessive hydrogenolysis is likely to occur, lower paraffins may grow, and the yield of BTX may decrease. Further, the reaction can be carried out in the presence of other gas components such as inert gas such as nitrogen gas, argon, and helium, or steam, within a range that does not interfere with the purpose of the present invention.

In the method of the present invention, the reaction raw material obtained by mixing the light hydrocarbon having 2 to 8 carbon atoms and the hydrocarbon having 9 or more carbon atoms of the specific combination in the specific ratio, or containing hydrogen therein. The resulting mixed raw material is brought into contact with the catalyst (that is, a catalyst containing zeolite having a CI value of 1 or more) and reacted to produce a hydrocarbon rich in BTχ.

By the way, the CI value is an index that indicates whether the zeolite pores have the necessary characteristics to control the entry of molecules with a cross section larger than that of n-paraffin, and is a control index that gives the definition of this CI value. The method of determining the value is fully described in US Pat. No. 4,016,218. The definition and measurement method of the CI value according to the present invention is in accordance with that described in US Pat. No. 4,016,218.

Specifically, the change in each of the two hydrocarbon hydrogens when a mixture of equal weights of n-hexane and 3-methylpentane is passed over a zeolite at 90-510"C and atmospheric pressure. Measure the amount remaining without

In the method of the present invention, various known zeolites can be used as the zeolite having a CI value of 1 or more to be used as the catalyst or its component, and specific examples thereof include, for example, ZSM- 5, ZSM-8, ZSM
ZSM-5 type zeolite such as -11, ZSM-23, Z
Examples include SM-35, clinoptilolite, and TMA offretite. Among these, ZSM-
ZSM-5 type zeolites such as 5, ZSM-8 and ZSM-11 are preferred.

In the method of the present invention, even if zeolite is used as a catalyst or its component, if a zeolite with a CI value of 1 or more is not used, the amount of BTXO produced will decrease and the object of the present invention cannot be achieved. .

The catalyst used in the method for producing BTX-rich hydrocarbons of the present invention contains at least one zeolite having the CI value of 1 or more, and this catalyst also has hydrogenation and dehydrogenation abilities. A certain amount of metal. Those containing these substances can be suitably used. Examples of metal elements serving as this metal component include Cu, Ag, Zn, Cd, and Ga.
, Cr, W, Se, Te, Re, Co, Ni, Pd, I
Mention may be made of r and Pt. Note that these metal elements can be used alone or in combination of two or more.

These metal components include, for example, metals, carbonates, sulfates,
It is added in various forms such as nitrates, oxides, sulfides, and chlorides. It is preferably used as an oxide or sulfide by processing such as calcination.

In constructing the catalyst or its components used in the method of the present invention, the various metal components can be used in various combinations with the zeolite. These various metals may be present, for example, in the structure of the zeolite (e.g., ion-exchangeable cations, substituted atoms in the framework, or if these metals are present during the preparation of the catalyst).
It may be contained in various forms resulting from denaturation during pretreatment, reaction, regeneration, etc.),
Alternatively, for example, an ion exchange method,
It may be contained in the form of being supported by an impregnation method or the like, or it may be contained in the form of a physical mixture with those zeolites, and it may be contained in any form.

In the method of the present invention, as the zeolite used as the catalyst or a part thereof, galloaluminosilicate and its modified zeolite are particularly preferably used among the various zeolites. In the galoaluminosilicate and its modified zeolite, the state of Ga may be an ionic state, a lattice substituted atom state, an oxide state, or a mixed state thereof. After synthesis, galloaluminosilicate is not necessarily in a four-coordinated state in which all Ga is incorporated into its lattice, but it is thought that six-coordinated gallium oxide exists. Also,
By subjecting galoaluminosilicate to a modification treatment such as high-temperature treatment or steam treatment, Ga can be removed from the lattice to form 6-coordinated Ga, resulting in a zeolite that provides more favorable catalytic properties such as activity. Can be done. Further, the high temperature treatment can be performed in any atmosphere such as air, inert gas, or hydrogen.

The shape of the catalyst used in the method of the present invention is not particularly limited, and it can be molded into various shapes as desired. For this purpose, a binder can be used as appropriate. Any binder can be used as long as it does not interfere with the purpose of the present invention, and specific examples include alumina, silica, silica/alumina, various clay minerals, etc. can be mentioned. Further, the catalyst may contain other additives within a range that does not interfere with the purpose of the present invention.

The method for preparing the catalyst used in the method of the present invention is not particularly limited, and can be prepared by applying various methods such as known methods.

For example, compounds containing the various metal components may be used in the various zeolites and prepared by an ion exchange method, an incorporation method, a physical mixing method, etc., or when synthesizing zeolite, the various types of zeolites may be added to the gel. A method may also be used in which a compound containing a certain amount of metal is included. Further, a certain amount of the various metals may be added before or after bonding with the binder. After the binder is impregnated or kneaded with a certain metal compound, this may be mixed with the zeolite.

The catalysts in various shapes thus prepared can be used as they are as catalysts in the method of the present invention, but they are usually subjected to air calcination as appropriate, and further subjected to various activation treatments and treatments as desired. It is preferable to perform pretreatment such as denaturation treatment before use. Examples of this modification treatment include the above-mentioned steam treatment, acid treatment, and other dealumination treatments, and activation treatments include, for example, dehydration by heat treatment in an inert gas or under vacuum exhaust. treatment, or reduction treatment using a reducing gas such as hydrogen gas. The catalytic activity can be further improved by these activation treatments and modification treatments, and the catalytic properties can also be adjusted as appropriate depending on the composition and properties of the reaction raw materials used. In the method of the present invention, the reaction can be carried out using various reaction methods and various reaction apparatuses suitable therefor, for example, it can be carried out using any of fixed bed, moving bed, fluidized bed, etc. Usually, it is preferable to use a fluidized bed. In particular, a system consisting of a fluidized bed reactor and a fluidized bed regenerator is used to carry out both the reaction and catalyst regeneration in a fluidized bed system, and the catalyst is circulated between the reactor and the catalyst regenerator, that is, the reaction-regeneration catalyst circulation fluidized bed. It is preferable to use a method. According to the fluidized bed, sufficient mixing and stirring of the catalyst particles can be achieved, and a relatively uniform temperature distribution can be obtained even when the reaction heat (endotherm) is large. Further, the supply and discharge of the catalyst are easy and can be carried out continuously during the reaction, and the reaction-catalyst regeneration can be carried out in a short cycle. Therefore, even if the catalyst is significantly deteriorated, the initially highly active regenerated catalyst can be used for the reaction at all times, and a highly active state can be maintained. In addition, when using the reaction-regenerated catalyst circulation fluidized bed system, the carbon number 2
If only the light hydrocarbons of ~8 are used as reaction raw materials, the amount of coke produced on the catalyst will be small, and therefore it will be difficult to maintain the regenerator temperature sufficiently using the combustion heat of this coke. It requires a large amount of fuel to maintain. However, in the method of the present invention, a reaction material having 9 or more carbon atoms containing the aromatic hydrocarbon is used as the reaction raw material. Since the reaction is carried out by adding hydrocarbons, the yield of coke is increased mainly due to its aromatic hydrocarbons, so the temperature of the regenerator can be effectively maintained by the calcination heat of this coke, which can be used separately. The amount of fuel used in the regenerator can be significantly reduced. In addition, since the amount of gas or liquid fuel with a high hydrogen content that is burned in the regenerator for heat replenishment can be significantly reduced, the amount of water in the regenerator is significantly reduced, ensuring the effect of preventing destruction of the zeolite catalyst. Can be done. Furthermore, by returning the sensible heat of the regenerated catalyst, which has been effectively increased by coke combustion in the regenerator, to the fluidized bed reactor, the main reaction (for example, from C2 to C8 hydrocarbons to B
It is possible to replenish the reaction heat (endotherm) of the reaction (reaction to TX).

In the method of the present invention, the reaction is usually carried out at a reaction temperature of 350 to 700°C and a reaction pressure of 0 to 10°C.
Within the range of kg/ciG, space velocity (WHS■) is 0.
It is appropriate to carry out within the range of 1 to 15 hr-'. For example, when carrying out the reaction using a fixed bed method, the above reaction conditions can be employed.

When using a fluidized bed method, the reaction temperature (reactor temperature) is usually 350 to 700°C, preferably 450 to 700°C.
The temperature is within the range of 600″C, and the reaction pressure is usually O~10k.
g/cdG, preferably within the range of O to 5 kg/ClllG, and the space velocity (WHSV) is 0. 1-1 5
h r-', while the temperature of the catalyst regenerator is usually 400-800°C, preferably 500-75°C.
within the range of 0°C, and the catalyst regeneration pressure is usually O~10k.
g/c1iG, preferably within the range of 0 to 5 kg/cIING.

If the reaction temperature is too high, undesirable decomposition reactions will occur, resulting in a decrease in the yield of BTX and the deterioration or destruction of the catalyst. On the other hand, if the reaction temperature is too low, sufficient reaction rate may not be achieved. Sometimes I can't.

In addition, if the catalyst regeneration temperature is too high, the catalyst may be easily destroyed, which may be disadvantageous in terms of energy costs and balance. On the other hand, if the catalyst regeneration temperature is too low, catalyst regeneration may be insufficient. .

In the above manner, the light hydrocarbons having 2 to 8 carbon atoms can be converted into BTX (benzene, toluene, xylene) with high yield.
can be converted into. In addition, the number of carbon atoms added is 9.
The above hydrocarbons can also be efficiently converted to BTX at the same time.

The reaction raw bottom obtained in this way contains a large amount of BTX, but it usually contains two-ring aromatic hydrocarbons such as naphthalene, hydrogen, and light hydrocarbons (baraffins and olefins with about 1 to 5 carbon atoms). ) etc. are also included.

The reaction product containing a high concentration of BTX thus obtained is separated into light hydrocarbons, gases such as hydrogen gas, and heavy hydrocarbon distillates by conventional separation means such as gas-liquid separation and distillation. By appropriately separating and removing the fractions, etc., it is possible to recover hydrocarbons (such as high-octane gasoline fractions) rich in BTX in a desired fraction range. At this time, the aromatic hydrocarbons that escaped to the gas side due to gas-liquid separation or the like can be recovered, for example, by countercurrent contact treatment with heavy aromatic hydrocarbons. The liquid after gas-liquid separation is usually separated and purified by distillation, but the distillation column bottom liquid (hydrocarbons heavier than the boiling point of gasoline) can be appropriately recycled to a reactor and used effectively if desired. Furthermore, if the catalyst discharged from the reactor together with the reactants is deposited at the bottom of the gas-liquid separator or distillation column, it can be appropriately returned to the reactor together with the recycled oil. Furthermore, hydrocarbon gases lighter than gasoline fractions (usually hydrocarbons with about 1 to 5 carbon atoms) and hydrogen gas can be recycled to the reactor as needed to further improve the aromatic conversion rate. can.

In the manner described above, hydrocarbons enriched in desired BTX can be efficiently produced.

The hydrocarbons enriched in the BTX obtained as described above can be suitably used as a mixed liquid as is, or by adjusting the composition as appropriate, for example, as a base material for livestock octanized gasoline, or It is also possible to appropriately separate useful components such as monocyclic aromatic hydrocarbons such as benzene, toluene, and xylene, and utilize them as petrochemical raw materials, high-quality solvents, and the like.

〔Example〕

Next, the present invention will be explained in more detail with reference to Examples and Comparative Examples, but the present invention is not limited thereto.

(Catalyst Preparation Example) 7.6 g of aluminum sulfate, 6.9 g of gallium nitrate, 2 grams of tetrapyrammonium bromide 6. 4 g
, a solution consisting of 15.0 g of sulfuric acid (97%) and 250 d of water was mixed with liquid (a), water glass (SiOz 2 8.4%, N
az09.5%) 214g, water 2 1 211Zi! A solution consisting of (b) consisting of 80 g of sodium chloride and 122 d of water is referred to as (C) liquid. (a) liquid, (b) liquid (
C) They were mixed while gradually dropping the mixture into the liquid at the same time. The reaction mixture was adjusted to pH 9.0 with sulfuric acid. After adjusting to
The mixture was maintained at 300 rpm+ for 20 hours with stirring.

After cooling, the mixture was filtered and thoroughly washed with excess pure water. After that, Z
We have synthesized a galloaluminosilicate zeolite with an SM-5 structure. This was then incinerated at 540°C for 3 hours in an air stream. After that, ion exchange was performed with IN aqueous solution of NH4NO3 at 80°C for 2 hours, followed by filtration,
After washing with water and drying at 120'C, in a stream of air 54
Burn it at 0'C, then heat the fired product to IN N84NO.
After ion exchange with water, filtration, washing with water, and repeated drying at 120°C, it was incinerated at 720°C in an air stream for 3 hours. The element m precept of this Galoal karma silicate is St.
yx : Alz (h : Gates (molar ratio) = 80:1:0.7, and its CI value was 8.1. Then, this galloaluminosilicate and alumina binder were kneaded to obtain a binder containing 135 wt%. year,
The mixture was granulated using a spray dryer and fired at 600°C for 3 hours to obtain a catalyst.

Examples 1 and 2 and Comparative Examples 1 and 2 Using the catalysts obtained in the above preparation examples, a reaction was carried out using a fluidized bed catalyst circulation regeneration type reactor in which the amount of catalyst in each reactor/regenerator was 200 cc.

The raw material is ■DLN (desulfide light naphtha) 10
0wt%,■DLN/LC○-75wt%/2 5
wt%, ■DLN/LCO=50wt%/5 0
wt%, ■DLN/light oil=50wt. %/50wt was used, and the total raw material supply amount was kept constant at 100 g/h. The general properties of the DLN, LCO, and light oil used are shown in Tables 1, 2, and 3.

The temperature of the reactor and the regenerator were heated by adjusting the output of the electric heater so that the temperature of the reactor and the regenerator were 530° C. and 650° C., respectively, in the case of feedstock oil and (2). In addition, the heater output of the reactor was the same as that when the raw material oil was ①, ②, or ②. The outputs of the regenerator heaters for feedstock oils (1), (2), and (2) were adjusted so that the regenerator temperature was constant at 650°C. Although efforts were made to prevent as much heat from escaping from the outer surface of the reactor and regenerator by wrapping heat insulating material around them, complete insulation was not achieved.

The circulation rate of the catalyst was adjusted to be about 1.8 kg/h when using raw oil (3). In the case of feedstock oils ①, ②, and ③, the circulation rate was adjusted so that the temperature of the reactor was 530'C.

Further, the pressure of the entire system was adjusted to be approximately 0.7 kg/cnG.

The products obtained in the reaction were analyzed using a gas chromatograph.

Table 4 shows the amount of catalyst circulation and the analysis results of raw materials (after 0.5 hr). The catalyst circulation amount in this result shows that the heat of reaction (endotherm) is reduced by adding LCO. This is dealkylation of monocyclic aromatic hydrocarbons contained in LCO,
Alternatively, this may be due to the reaction (heat generation) of polycyclic aromatic hydrocarbons to monocyclic aromatic hydrocarbons.

Comparison of the results for feedstock oil ■ and feedstock oil with LC○ added shows that the amount of BTX in the raw material hydrocarbons hardly changes, and at least when the LCO amount is 25 wt% or less, the reaction heat is reduced without changing the BTX yield. It can be seen that (endotherm) is reduced.

In addition, feedstock oil (■) with LCO added has a higher BTX per light hydrocarbon having 2 to 8 carbon atoms than feedstock (■).
It can be seen that the amount of production is increasing. Also,■
From the comparison between and (2), it can be seen that the amount of coke increases with LCO addition (2) than with light oil addition (2), which makes it possible to reduce the external heat supply required to maintain the temperature of the regenerator.

Table 1 Raw material DLN composition DMB: Dimethylbutane MP; Methylpentane MCP: Methylcyclobentane Since the reaction is carried out by adding a specified amount or more of a hydrocarbon having 9 or more carbon atoms, the following effects can be achieved.

(1) Since the hydrogenolysis of polycyclic aromatics in the added hydrocarbons having 9 or more carbon atoms and the dealkylation of monocyclic and polycyclic aromatic hydrocarbons are exothermic, due to the simultaneous occurrence of these reactions, etc. The heat of reaction (endotherm 31) in the reactor can be reduced.

(2) By using a fluidized bed reactor equipped with a catalyst regenerator, the reaction and catalyst regeneration can be repeated in a short time, and the high activity of the catalyst with little initial deterioration can be constantly utilized. Due to the action of aromatic hydrocarbons such as polycyclic aromatic hydrocarbons in the hydrocarbon fraction of number 9 or more, the amount of coke produced on the catalyst increases moderately, and this becomes effective as a heat source during catalyst regeneration. This makes it possible to significantly reduce the amount of heat required from outside to maintain the temperature of the catalyst regenerator, that is, the energy cost. In addition, the sensible heat of the regenerated catalyst can be effectively used in the fluidized bed reactor.
The effect of (1) above can be further improved. As described above, according to the present invention, a certain amount of raw material hydrocarbons including light hydrocarbons having 2 to 8 carbon atoms can be converted into BT with high yield.
It is possible to provide a method for producing BTX-rich hydrocarbons that can be converted to X and efficiently produce BTX-rich hydrocarbons, which is extremely advantageous in practice.

Claims (1)

[Scope of Claims] 1. A hydrocarbon having 9 or more carbon atoms containing 40% by weight or more of an aromatic hydrocarbon and 3% or more by weight of a polycyclic aromatic hydrocarbon in a light hydrocarbon having 2 to 8 carbon atoms. is added in an amount of 1 to 50% by weight of the total hydrocarbons, and the reaction is carried out in the presence of a catalyst containing zeolite having a CI value of 1 or more. Production method. 2. The method for producing a BTX-rich hydrocarbon according to claim 1, wherein the addition ratio of the hydrocarbon having 9 or more carbon atoms is 1 to 30% by weight of the total hydrocarbon. 3. The catalyst is Cu, Ag, Zn, Cd, Ga, Cr, W,
The method for producing a BTX-rich hydrocarbon according to claim 1 or 2, which contains one or more metal elements selected from Se, Te, Re, Co, Ni, Pd, Ir, and Pt. 4. The molar ratio (H_2/HC) of hydrogen (H_2) and total hydrocarbons (HC) supplied to the reaction system is 0 or more and 1
BT according to claim 1, 2 or 3, which is carried out within the following range:
A method for producing an X-rich hydrocarbon. 5. BTX according to any one of claims 1 to 4, wherein the reaction is carried out using a device consisting of a fluidized bed reactor and a fluidized bed regenerator.
A method for producing hydrocarbons rich in 6. Claims 1 to 5 wherein the hydrocarbon having 9 or more carbon atoms is from FCC (fluid catalytic cracking) circulating oil, coal liquefied oil, heavy oil pyrolysis process oil, or heavy oil hydrocracking oil. A method for producing a BTX-rich hydrocarbon according to any one of the above.