RU2246474C1 - Method for preparing alkylated polycyclic aromatic hydrocarbons - Google Patents

Abstract

FIELD: petroleum chemistry, organic chemistry, chemical technology.

SUBSTANCE: method involves carrying out the interaction condensed and polynuclear aromatic hydrocarbons, in particular, naphthalene and biphenyl with polyalkylaromatic hydrocarbons, in particular, with diisopropyl benzene under transalkylation conditions with aim to prepare dialkylated condensed and polynuclear aromatic hydrocarbons. Transalkylation reaction is carried out in the presence of zeolite catalysts comprising 12-membered oxygen rings with diameter of zeolite channels from 5.6 to 7.7

. Invention provides the development of new method for preparing dialkylated polycyclic hydrocarbons.

EFFECT: improved preparing method.

10 cl, 2 tbl, 31 ex

Description

The invention relates to petrochemical processes, and more specifically to methods for producing alkylated polycyclic aromatic hydrocarbons, which are widely used in various fields of science and technology, namely as drugs, as agrochemical compounds, as solvents and as liquid crystals.

At present, transalkylation processes are widely used in industrial processes to produce monoalkylated aromatic hydrocarbons, mainly for the production of cumene and ethylbenzene. Transalkylation is also often used in conjunction with the alkylation process to convert the resulting polyalkylated compounds to increase the selectivity of formation and yield of the desired monoalkylated product. In this case, transalkylation can be carried out either in a separate transalkylation zone or by recycling the resulting polyalkylbenzenes in the alkylation zone. Of the obtained alkylated polycyclic aromatic hydrocarbons, the most interesting are disubstituted alkyl derivatives of biphenyl having alkyl substituents in the para, para'-positions and β, β'-dialkylnaphthalenes. Such compounds by oxidation can be converted into monomers for the production of liquid crystalline polymers.

In the methods for transalkylation of aromatic hydrocarbons, Friedel-Crafts catalysts are widely used, such as aluminum chloride, boron fluoride, hydrogen fluoride, phosphoric acid in liquid and solid state, sulfuric acid, and the like. However, these catalysts have several disadvantages: low selectivity, equipment corrosion, environmental pollution, the allocation of used catalyst. Solid acid catalysts such as zeolites are devoid of these disadvantages.

A known method of producing monoalkylated hydrocarbons by transalkylation of polyalkylated aromatic hydrocarbons on ultrastable zeolite Y (US patent 4169111), narrow pore zeolites, preferably ZSM-5 and ZSM-11 with a molar ratio of SiO ₂ / Al ₂ About ₃ less than 40 (EP 308097). ZSM-5, ZSM-11, ZSM-12, ZSM-23, ZSM-35, ZSM-38, ZSM-48 with a molar ratio of SiO ₂ / Al ₂ O ₃ not less than 100: 1, modified with aluminum fluoride (US 4577048) .

A liquid-phase process of transalkylation of an aromatic or alkylaromatic hydrocarbon, for example benzene, toluene, xylene or a mixture thereof with a polyalkyl aromatic hydrocarbon, for example diisopropylbenzene, in the presence of a Beta catalyst with Si / Al from 5: 1 to 100: 1 (EP 439632 and US 4,891,458), mordenite ( US 5,243,116), phosphoric acid modified Y-zeolite (US 5650547) or ERS-10 (US 6005152), as well as a gas-phase process in the presence of hydrogen on SSZ-26, Al-SSZ-33, CIT-1, SSZ-35, SSZ-44, preferably containing nickel or palladium. The catalyst can be used in pure form, or with a binder, for example Al ₂ About ₃ .

US Pat. No. 5,723,710 for transalkylation of an aromatic compound, including naphthalene, with a polyalkylated aromatic compound with alkyl groups containing from 2 to 20 carbon atoms, proposes a new modified form of Beta zeolite, calcined, and etched, modified on the surface, characterized in that it has energy binding of 2p aluminum on the surface, measured by X-ray spectroscopy of at least 74.8 eV, which can significantly increase stability and runtime catalyst.

An effective method for transalkylation of an aromatic hydrocarbon with a polyalkyl aromatic compound on a catalyst is known, which is a zeolite bound zeolite catalyst comprising first crystals of the first zeolite and a binder containing second crystals of the second zeolite, the average particle size of which is smaller than the first crystals, the second crystals being in spliced state with the first crystals and form from them a coating or partial coating (RU 2177468, US 5993642, US 6039864, US 6111157, US 6458736).

It is known that the transalkylation reaction of polyalkylaromatic hydrocarbons is often used in combination with an alkylation reaction to increase the yield of monoalkylated compounds.

It is known that the transalkylation of polyalkylated aromatic hydrocarbons formed in the alkylation reaction proceeds efficiently on ultrastable Y zeolite, pure or molded with aluminum oxides, metal oxides of IA and IIA groups in a ratio of 50:50 to 95: 5 (US patent 4459426), mordenite (US 4774377), Zeolite Beta (EP 439632, US 4891458), ERS-10 (US 6005152).

All of the above patents relate to transalkylation of monoalkylated aromatic hydrocarbons, mainly ethylbenzene and cumene.

The closest in technical essence in relation to the proposed method for producing dialkylated aromatic binuclear and condensed hydrocarbons is the method described in patent US 5302769.

In this method, alkyl substituted aromatic compounds such as toluene, o-, m-, p-xylene, mesitylene react with polycyclic aromatic hydrocarbons such as naphthalene, phenanthrene, biphenyl, benzothiophene and dibenzothiophene on zeolite catalysts such as Beta, USY, ZSM-5. The reaction proceeds in a flow reactor at temperatures of 370-600 ° C, pressure 1-60 atm, WHSV 0.5-15 h ^-1 , the molar ratio of polycyclic aromatic hydrocarbon to alkylated aromatic hydrocarbon from 1:10 to 10: 1. The reaction can be carried out in a stream of hydrogen to increase the operating time of the catalyst. However, only methylated polycyclic aromatic compounds can be obtained by this method.

The basis of the invention is the task of developing a new method for producing dialkylated polycyclic hydrocarbons, in particular 4,4 'diisopropylbenzenes and β, β'-diisopropylnaphthalenes by transalkylation of condensed and polynuclear aromatic hydrocarbons with polyalkylaromatic hydrocarbons.

. Также согласно изобретению полиядерное ароматическое соединение взято из группы, включающей бифенил, 1,4-дифенилбензол; конденсированный ароматический углеводород взят из группы, включающей нафталин, фенантрен, антрацен; диалкилбензол взят из группы, включающей диэтилбензол, диизопропилбензол, диизобутилбензол. Взаимодействие полиядерных и конденсированных соединений осуществляют в условиях непрерывного потока в реакторе с неподвижным слоем катализатора в условиях жидкофазного или газожидкофазного трансалкилирования в интервале Т от 150 до 400°С, Р от 1 до 30 атм, массовой скорости подачи сырья от 1,3 до 30 ч^-1 и мольном отношении полициклического углеводорода к полиалкилароматическому углеводороду от 1:5 до 1:20. При газожидкофазном трансалкилировании реакцию проводят в присутствии инертного газа, например азота, что способствует улучшению показателей процесса. Мольное отношение газ-разбавитель : полициклический углеводород берут равным 10:1. В качестве цеолита с 12-членными кольцами используют морденит. Бета, ZSM-12 или фожазит. Исходный морденит может быть деалюминирован щавелевой или метансульфоновой кислотами либо перед обработкой щавелевой или метансульфоновой кислотами прокален при температурах 700-900°С.The problem is solved in that in the method for producing alkylated polycyclic aromatic hydrocarbons, comprising reacting a polycyclic aromatic hydrocarbon with a polyalkyl aromatic compound in the presence of a catalyst, according to the invention, the interaction of these reagents is carried out by transalkylation and a polynuclear or condensed aromatic hydrocarbon is taken as a polycyclic aromatic hydrocarbon as a polyalkyl aromatic compound dialkylb taken nzol, wherein the reaction is carried out in the presence of a catalyst comprising a zeolite having the structure of 12-membered oxygen ring channels with a diameter zeolite from 5.6 to 7.7

. Also according to the invention, the polynuclear aromatic compound is taken from the group consisting of biphenyl, 1,4-diphenylbenzene; a condensed aromatic hydrocarbon is taken from the group comprising naphthalene, phenanthrene, anthracene; dialkylbenzene is taken from the group consisting of diethylbenzene, diisopropylbenzene, diisobutylbenzene. The interaction of polynuclear and condensed compounds is carried out under continuous flow in a reactor with a fixed catalyst bed under liquid-phase or gas-liquid-phase transalkylation in the range T from 150 to 400 ° C, P from 1 to 30 atm, mass feed rate from 1.3 to 30 hours ^-1 and a molar ratio of polycyclic hydrocarbon to polyalkylaromatic hydrocarbon from 1: 5 to 1:20. In gas-liquid phase transalkylation, the reaction is carried out in the presence of an inert gas, for example nitrogen, which improves process performance. The molar ratio of gas diluent: polycyclic hydrocarbon is taken equal to 10: 1. Mordenite is used as a zeolite with 12 membered rings. Beta, ZSM-12 or Fojazit. The starting mordenite can be dealuminated with oxalic or methanesulfonic acids or calcined at temperatures of 700-900 ° C before treatment with oxalic or methanesulfonic acids.

The proposed method for transalkylation of condensed and binuclear aromatic hydrocarbons is as follows.

Preliminary preparation of the catalyst before the experiment consists in the fact that a sample of a catalyst weighing 700 mg of a fraction of 0.5-1 mm is placed in a reactor between two layers of quartz. The standard processing of all catalysts before the experiment consists in calcining them in a stream of dry air at 550 ° C for 6 hours. Before the experiment, the catalyst is preheated in a stream of inert gas (nitrogen, helium) to 300 ° C for 1 hour and calcined at this temperature for 30 minutes, then the reactor is cooled to the temperature of the experiment. A mixture of a polycyclic hydrocarbon (biphenyl or naphthalene) with diisopropylbenzene is fed to a flow-type reactor with a fixed catalyst bed. The reaction is carried out under a pressure of 1-30 atm, in the temperature range of 150-400 ° C, the molar ratio of polycyclic hydrocarbon to polyalkyl aromatic hydrocarbon is from 1: 5 to 1:20, the feed rate is selected in the range of 1.3-30 h ^-1 . When carrying out transalkylation in the presence of a nitrogen diluent gas, the molar ratio of the diluent gas to the polycyclic hydrocarbon is taken to be 10: 1. At the outlet of the reactor, the resulting products are separated into liquid and gaseous, the component composition is determined by chromatographic method.

The method uses zeolite mordenite catalysts. Beta, ZSM-12, Faujasite.

The known mordenite with the ratio SiO ₂ / Al ₂ O ₃ = 10 (MOR), Beta with SiO ₂ / Al ₂ O ₃ = 300, faujasite with SiO ₂ / Al ₂ O ₃ = 30 (Y), ZSM -12 with SiO ₂ / Al ₂ O ₃ = 140. Zeolites Beta and faujasite are a hydrogen form. To obtain the proton form of mordenite and ZSM-12, ion exchange is used in a solution of ammonium nitrate, followed by calcination at 550 ° C. The dealuminated form of mordenite is obtained from the H-form either by treatment with oxalic or methanesulfonic acid, or by calcination in the temperature range from 700 to 900 ° C for 6 hours, followed by treatment with oxalic or methanesulfonic acid. To determine the composition of the catalyst, elemental analysis data were used; the type of crystal structure was confirmed by x-ray phase analysis.

Below, specific examples of the implementation of the proposed method will be considered, while examples 1-13 describe a method for transalkylation of biphenyl with diisopropylbenzene, and in examples 14-31, naphthalene with diisopropylbenzene.

Example 1

In accordance with the above technology, the transalkylation of biphenyl (BP) with diisopropylbenzene (DIPB) is carried out as follows.

The MOR catalyst is placed in a flow reactor, purged with nitrogen at a temperature of 300 ° C, then the temperature is reduced to 220 ° C and at a pressure of 10 atm a mixture of biphenyl with diisopropylbenzene is fed in a ratio of 1: 5 at a mass feed rate of 3.2 h ^-1 . The ratio of nitrogen to biphenyl is 10: 1. The results are presented in table 1.

Example 2

Transalkylation of biphenyl is carried out analogously to example 1, using dealuminated mordenite obtained by calcining MOR at a temperature of 750 ° C, followed by boiling for 2 hours with stirring in a 2M solution of oxalic acid. As a result, a MOR-750-Ox zeolite with a ratio of SiO ₂ / Al ₂ O ₃ = 480 was obtained. The results are presented in table 1.

Example 3

Transalkylation of biphenyl is carried out analogously to example 1, using dealuminated mordenite obtained by calcining MOR at a temperature of 750 ° C, followed by boiling for 2 hours with stirring in a 6M solution of methanesulfonic acid. The result is a zeolite MOR-750-MS with a ratio of SiO ₂ / Al ₂ O ₃ = 160. The results are presented in table 1.

Examples 4-11.

Transalkylation of biphenyl is carried out analogously to example 2, while changing the temperature, pressure of the reaction, the feed rate of the reagents, as well as the ratio of biphenyl: DIPB: nitrogen. The experimental conditions and results are presented in table 1.

Example 12

Transalkylation of biphenyl is carried out analogously to example 1, using the catalyst ZSM-12.

Example 13

Transalkylation of biphenyl is carried out analogously to example 1, using a Beta catalyst. The results are presented in table 1.

Example 14

In accordance with the above technology, the transalkylation of naphthalene (H) with diisopropylbenzene (DIPB) is carried out as follows. The MOR catalyst is placed in a flow reactor, purged with nitrogen at a temperature of 300 ° C, then the temperature is reduced to 250 ° C and at a pressure of 1 atm a mixture of naphthalene with diisopropylbenzene is fed in a ratio of 1: 5 at a mass feed rate of 1.3 h ^-1 . The results are presented in table 2.

Example 15

Transalkylation of naphthalene is carried out analogously to example 14, using dealuminated mordenite obtained by boiling MOR for 2 hours with stirring in a 2M solution of oxalic acid. As a result, a MOR-Ox zeolite with a ratio of SiO ₂ / Al ₂ O ₃ = 150 was obtained. The results are presented in table 2.

Example 16

Transalkylation of naphthalene is carried out analogously to example 14, using dealuminated mordenite obtained by boiling MOR for 2 hours with stirring in a 6M solution of methanesulfonic acid. As a result, a MOR-MS zeolite with a ratio of SiO ₂ / Al ₂ O ₃ = 100 was obtained. The results are presented in table 2.

Example 17

Transalkylation of naphthalene is carried out analogously to example 15, while when performing dealumination before treatment with acid, the catalyst is calcined at 700 ° C. As a result, a zeolite MOR-700-Ox with a ratio of SiO ₂ / Al ₂ O ₃ = 320 was obtained. The results are presented in table 2.

Example 18

Transalkylation of naphthalene is carried out analogously to example 15, while when performing dealumination before treatment with acid, the catalyst is calcined at 750 ° C. As a result, a MOR-750-Ox zeolite with a ratio of SiO ₂ / Al ₂ O ₃ = 480 was obtained. The results are presented in table 2.

Example 19

Transalkylation of naphthalene is carried out analogously to example 15, while when performing dealumination before treatment with acid, the catalyst is calcined at 900 ° C. The result is a zeolite MOR-900-Ox with a ratio of SiO ₂ / Al ₂ O ₃ = 180. The results are presented in table 2.

Example 20

Transalkylation of naphthalene is carried out analogously to example 16, while when performing dealumination before treatment with acid, the catalyst is calcined at 750 ° C. The result is a zeolite MOR-750-MS with a ratio of SiO ₂ / Al ₂ O ₃ = 160. The results are presented in table 2.

Examples 21-24.

Similar to example 14, the difference is that the temperature of the reaction was changed. The experimental conditions and results are presented in table 2.

Examples 25-28.

Similar to example 18, the difference is that they changed the feed rate. The experimental conditions and results are presented in table 2.

Example 29

Similar to example 18, the difference lies in the fact that serves a mixture of naphthalene to DIPB in a molar ratio of 1:20. The results are presented in table 2.

Example 30

Similar to example 14, the difference is that they use a Beta catalyst. The results are presented in table 2.

Example 31

Similar to example 14, the difference is that they use catalyst Y. The results obtained are presented in table 2.

Claims (10)

1. A method of producing alkylated polycyclic aromatic hydrocarbons, comprising reacting a polycyclic aromatic hydrocarbon with a polyalkyl aromatic compound in the presence of a catalyst, characterized in that the interaction of these reagents is carried out by transalkylation and a poly nuclear or condensed aromatic hydrocarbon is taken as a polycyclic aromatic hydrocarbon, dialkylbenzene is taken as the polyalkyl aromatic compound , while the interaction is about odyat in the presence of a catalyst comprising a zeolite having the structure of 12-membered oxygen ring having a diameter zeolite channels 5.6 - 7.7

. 2. The method according to claim 1, characterized in that the polynuclear aromatic compound is taken from the group comprising biphenyl, 1,4-diphenylbenzene. 3. The method according to claim 1, characterized in that the condensed aromatic hydrocarbon is taken from the group comprising naphthalene, phenanthrene, anthracene. 4. The method according to claim 1, characterized in that the dialkylbenzene is taken from the group comprising diethylbenzene, diisopropylbenzene, diisobutylbenzene. 5. The method according to claim 1, characterized in that the interaction of polynuclear and condensed compounds is carried out under continuous flow in a reactor with a fixed catalyst bed under liquid-phase or gas-liquid phase transalkylation. 6. The method according to claim 5, characterized in that the liquid-phase transalkylation is carried out in the range of T from 150 to 400 ° C, P from 1 to 30 atm, a mass feed rate of from 1.3 to 30 h ^-1 and a molar ratio of polycyclic hydrocarbon to polyalkyl aromatic hydrocarbon from 1: 5 to 1:20. 7. The method according to claim 5, characterized in that the gas-liquid phase transalkylation is carried out in the range of T from 150 to 400 ° C, P from 1 to 30 atm, a mass feed rate of 0.5 to 30 h ^-1 and a molar ratio of polycyclic hydrocarbon to a polyalkyl aromatic hydrocarbon from 1: 5 to 1:20 in the presence of an inert gas, for example nitrogen. 8. The method according to claim 1, characterized in that mordenite, Beta, ZSM-12 or faujasite are taken as zeolite with 12-membered rings. 9. The method according to claim 8, characterized in that the starting mordenite is dealuminated with oxalic or methanesulfonic acids. 10. The method according to claim 9, characterized in that before treatment with oxalic or methanesulfonic acids, mordenite is calcined in the temperature range of 700 - 900 ° C.