Method of extracting benzene from mixtures with non-aromatic hydrocarbons

FIELD: chemistry.

SUBSTANCE: invention relates to a method of extracting benzene from mixtures with non-aromatic hydrocarbons, simultaneously obtaining distillate through extractive rectification, characterised by that the selective solvent used is in form of mixtures containing 14.7-48.5 wt % sulfolane or N-formylmorpholine and 48.5-83.3 wt % methylpyrrolidone, containing 2-3 wt % water.

EFFECT: use of given method allows for obtaining benzene, toluene and distillate containing not more than 1-1,5 vol. % benzene, which can be used as a component of motor car fuel or as raw material for pyrolysis process.

1 cl, 1 ex, 4 tbl, 2 dwg

 

The invention relates to the refining and petrochemical industries and can be used for separation of benzene and toluene from benzene fraction of the reformate and the simultaneous achievement of a component of gasoline.

In accordance with European specifications for motor gasoline Euro-4, applicable from 2005, benzene content must not exceed 1% (vol.) [1]. At the same time, the main component of the Russian automotive gasoline is catalysate reforming of gasoline fractions NK - 180°C with the concentration of benzene 3-5% (by vol.).

For large refineries with resources reformative more than 1.5 million tons/year the most cost-effective strategy for reducing the benzene content in motor gasoline - postvaccinial of reformate gasoline fraction, followed by separation of benzene from the benzene fraction by extractive distillation [2]. As selective solvents of the process of extractive distillation in the industry are the N-organic [3], N-formylmorpholine [4], a mixed solvent "Aktiv-100" [5].

The main disadvantage of the selective solvent (sulfolane, N-formylmorpholine and others) is not sufficiently high solvent capacity with regard to hydrocarbons, leading to delamination of the liquid on the plates of the column extractive powder, sweet potato is th rectification and reduce the effectiveness of the selection process benzene. To prevent delamination of the system hydrocarbon - selective solvent patented method of allocation arenes from hydrocarbon mixtures by extractive distillation with N-formylmorpholine, wherein the process is conducted at elevated pressures up to 0.5 MPa [6]. High blood pressure increases the temperature in the column and increase the solubility of saturated hydrocarbons in the N-formylmorpholine. However, the drawback of the proposed method lies in the fact that with increasing temperature decreases the stability of the π-complexes of arenes with polar solvents, which reduces the selectivity of the separation.

N-Organic has a very high dissolving ability, which leads to the homogeneity of the system on the plates of the column extractive distillation, however, this solvent is less selective with respect to the arenas than sulfolane and N-formylmorpholine.

The composition of the mixed solvent "Aktiv-100" is not indicated, however, judging by the use of vacuum and high-pressure steam in the Stripping column distillation arenes, composed of high boiling selective solvent type sulfolane, the regeneration of which is carried out in a similar way [7].

Closest to the technical essence and the achieved effect of the present invention, the method of selection arenes the C hydrocarbon fraction by extractive distillation using a mixture of sulfolane with the co-solvent is alkylsulfonyl containing up to 8 atoms in molecules (proc. Pat. 0183642, 2001; S.A., V.135, 346146). The disadvantages of this method, adopted as a prototype, the following:

- use vysokosidyaschih selective solvents (boiling point of sulfolane 28°C, alkylsulfonate - even higher) leads to high temperatures in the extractive distillation column and the reboiler and decrease the selectivity of the separation process;

the high viscosity of the mixed solvent reduces the efficiency of the plates and the number of theoretical plates of the column extractive distillation;

- difficulties in the regeneration of solvents: the need to use water vapor generator high pressure and vacuum Stripping column;

to use a vacuum system and vacuum columns increased diameter compared to the atmospheric Stripping column leads to increased capital expenditures.

The purpose of this invention is to eliminate the above disadvantages. This goal is achieved by adding to a highly selective solvent of relatively low-boiling and low-viscosity solvent having a higher solubility with respect to hydrocarbons. As the latter is suggested to use N-organic, and as vysokomolek the main solvents - sulfolane and N-formylmorpholine.

Physico-chemical and selective properties of these solvents are listed in table 1. As follows from the presented data, sulfolane and N-formylmorpholine significantly selektivnoe N-methylpyrrolidone in relation to the model system hexane-benzene, as evidenced by the ratio of the limiting activity coefficients of these hydrocarbon solvents.

At the same time, N-organic has higher solvent capacity, characterized by the reciprocal of the limiting activity coefficient of benzene. Integrated criterion of efficiency, taking into account both selectivity and solvent power, sulfolane and N-organic differ slightly. Advantages N-methylpyrrolidone - smaller values of viscosity, enthalpy of vaporization and freezing temperature.

The raw material used industrial benzene fraction 55-85°C, isolated by distillation from the reformate gasoline fraction NK - 180°C, containing 30.48% of the mass. benzene and 0.46% of the mass. of toluene.

Experiments extractive distillation was carried out at the Packed distillation column efficiency 15 theoretical plates. Conditions and results of experiments extractive distillation with sulfolane, N-methylpyrrolidone and mixtures of these solvents are given in table 2. Figure 1 presents the dependence of the degree of extraction of arenes by the composition of the extractants in their mass with respect to raw materials 2:1.

As follows from table 2 and figure 1, the use of a mixed solvent sulfolan - N-methylpyrrolidone containing 2% of the mass. water to reduce the temperature in the reboiler, is more effective than individual solvents. Thus, the use of mixed solvent sulfolan - N-organic characterized by the manifestation of a synergistic effect. In the optimal solvent composition contains 14.7% of the mass. sulfolane, 83.3% of the mass. N-methylpyrrolidone and 2% of the mass. water. When the composition of the mixed solvent to reduce the concentration of benzene in the distillate to less than 1% (vol.) just use the mass ratio of solvent to raw materials 1.5:1, and the degree of extraction of benzene is about 98% of the mass. The higher efficiency of the mixed solvent compared to sulfolane can be explained by the transition from two-phase to a homogeneous system in the column and decrease the process temperature, as compared with the N-organic - enhanced selectivity of the mixed solvent.

Conditions and results of experiments extractive distillation with N-formylmorpholine, N-organic and mixtures of these solvents is given in table 3. Figure 2 presents addicted is here the degree of extraction of arenes by the composition of the extractants in their mass with respect to the raw material of 1.5:1. As follows from table 3 and figure 2, the use of a mixed solvent of N-formylmorpholine - N-organic containing 3% of the mass. water, leads to a synergistic effect more effectively than the use of individual solvents. In the optimal solvent composition contains 29% of the mass. N-formylmorpholine, 68% of the mass. N-methylpyrrolidone and 3% of the mass. water. When the mass ratio of solvent to raw materials 1.5:1 benzene content in the distillate is reduced to 2.13% of the mass. or about 1.7% (vol.). Due to the fact that the distillate in the production of gasoline mixed with the reformate fraction 85-180°C, isomerizate, alkylates, octane additives that do not contain benzene, the degree of extraction of benzene at 95% of the mass. can be considered sufficient. By reducing the water content in the mixed solvent to 2% of the mass. and increasing the ratio of solvent to raw materials up to 2.5:1, the concentration of benzene in the distillate is reduced to less than 1% (by vol.).

Higher efficiency of mixed solvents containing 14.7-48.5% of the mass. sulfolane or N-formylmorpholine and 48.5-83.3% of the mass. N-methylpyrrolidone and 2-3% of the mass. water compared to individual solvents is also confirmed by experimental data on the coefficients of relative volatility model system heptane-benzene (table 4). The content of benzene in a hydrocarbon mixture 30% of the mass. m is sawoe the ratio of solvent to hydrocarbon of 2:1, the total pressure is 760 mm Hg

In table 4 summarizes the constants of the phase equilibrium heptane (Kaboutse) and benzene (Kb) and the coefficients of relative volatility {a) system heptane-benzene.

According to [5] the coefficients of the relative volatility of the system heptane-benzene in the presence of N-formylmorpholine and sulfolane equal to 1.89 and 2.00, respectively, lower than when using the proposed mixed solvents.

Example.

In the cube column extractive distillation efficiency 15 theoretical plates load of 100 g of benzene fraction 55-85°C reformate containing 30.48% of the mass. benzene, 0.46% of the mass. toluene and 69.06% of the mass. nah6-C7. The cube contents are heated to boiling in the upper part of the column serves a mixed solvent of N-formylmorpholine - N organic - water composition 29.4/68.6/2.0% wt. when the volume ratio of the distillate of about 1.9:1. Take a few fractions of distillate and analyze their composition by gas chromatography. Experience stop when the estimated content of arenes in the hydrocarbon part of the VAT residue reaches 99.9% wt. Thus the temperature of the bottom liquid is 160°C, and the mass ratio of the selective solvent to the raw material 2:1. The composition of the distillate and of the cubic residue is analyzed by gas chromatography and SOS is ablaut material balance of experience extractive distillation.

Aromatic hydrocarbons distilled from VAT residue with acute water vapor, while the regeneration of mixed selective solvent. Nonaromatic hydrocarbons remaining in an admixture 0.1% max., presents isomers of dimethylcyclopentane and n-heptane with a boiling point above 90°C.

Sources of information

1. Kaminsky ET, Khavkin VA Deep oil processing: technological and economic aspects. - M.: Publishing house "Technika". LLC "TOMOGRAPH", 2001, 384 S.

2. Sirimanna A.A., vihman A.G., Maryshev IB and other Analysis options for reducing the benzene content in reformate // World petroleum products. 2006. N 5, p.26-27.

3. Gail A.A., Zalishevskiy GD N-Organic. Production, properties and use as a selective solvent. SPb.: Hemostat, 2005. 704 S.

4. Gail A.A., Som V.E., Zalishevskiy HD Morpholine and its derivatives. Production, properties and application as selective solvents. - SPb.: Hemostat, 2007. - 336 S.

5. Gentry JK, Kumar, K.S., Lee, oil on canvas, Whether IH the Production of aromatic hydrocarbons technology GT-BTXSM// Chemistry and technology of fuels and oils. 2003. N 1-2. P.12-17.

6. Preusser G., Richter, K., Schulze M. Separation of aromatics from hydrocarbon mixtures: U.S. Pat. 2005648 Germany, 1971.

7. Gail A.A., Som V.E., Warsaw O.M., Semenov L.V. Sulfolan: Properties and application as a selective solvent. SPb: Hemostat, 1998.144 C.

Table 1
Physico-chemical and selective properties of the solvents in the allocation of benzene mixtures of saturated hydrocarbons
NameSulfo LAN [7]N-Formular Foligno [4]N-Organic [3]
Boiling point, °C285244202-204
Pour point, °C28,420-23-24
Density at 30°C, g/cm3Absorbance 1.2621.1421.0217
Dynamic viscosity, centipoise
at 30°C10.2866.681.54
75°C3.852.40.88
at 30°Cof 1.341.641.80
100°C1.462.012.03
The enthalpy of vaporization at the normal boiling point, kJ/mol54.546.144
Limiting activity coefficients in
the solvents at 30°C:
71.942.014.1
2.432.281.08
Selectivity29.618.413.1
Dissolving ability0.4120.4390.926
The criterion of effectiveness12.28.0812.1

Table 2
The results of the allocation of benzene from the benzene fraction of the reformate extractive rectification with sulfolane, N-organic and mixed solvents
The composition of the solvent, wt.%The mass ratio of solvent:
raw materials
The temperature in the reboiler, °CThe yield of distillate,
wt.%.
The selection of non-aromatic hydrocarbons with distilled water, % wt.The content of arenes, % wt.The degree of extraction, % wt.
sulfolanN-MPwaterdis is illat VAT residuethe amount arenesbenzene
29.2568.252.52: 115070.2399.941.7699.8796.095.94
29.468.62.02: 114869.5799.940.7799.8798.2598.23
14.783.32.02: 115069.3299.620.6399.2798.5898.56
-98.02.02: 114570.05 99.971.4499.995.2595.2
98.0-2.02: 116573.9999.976.6799.983.9983.64
14.783.32.01.5:114069.6599.940.8999.8798.097.97
"""1:114570.2599.941.8299.8795.8795.81

Table 4
Constants f the new equilibrium heptane and benzene (Kb) and the coefficients of relative volatility (α)
system heptane - benzene
The composition of the extractant, % wt.T-RA, °CThe concentration of benzene mol%.Kbα
in the vapor phase, Inbin the liquid phase,
Xb
N-Organic - 989829.244.81.280.651.97
Water - 2
N-Organic - 83.310326.745.681.350.582.33
Sulfolan - 14.7
Water - 2
N-Organic - 68.610327.6At 46.271.350.602.25
N-Formylmorpholine - 29.4
Water - 2

Method of extraction of benzene from mixtures with non-aromatic hydrocarbons and the simultaneous achievement of distillate of the extractive rectification, characterized in that as the selective solvent mixtures are used which contain 14,7-to 48.5 wt.% sulfolane or N-formylmorpholine and 48,5-83,3 wt.% methylpyrrolidone containing 2-Mas.% water.



 

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21 cl, 4 dwg

FIELD: chemistry.

SUBSTANCE: invention relates to a continuous stepped counterflow method of catalytic oxidation in a solvent of at least one benzene compound, containing two substituting groups, which are selected from alkyl, hydroxyalkyl, aldehyde, carboxyl groups and their mixtures, which can be oxidised to the corresponding acid derivative, involving the following steps: (a) introducing a mixture of material into the first oxidation step, containing at least part of the total amount of each of: (i) solvent, which is an organic acid, (ii) at least one catalytically active metal, selected from manganese, cobalt, nickel, zirconium, hafnium, cerium and their mixtures, and (iii) bromine in molar ratio, in terms of all catalytically active metals, in the interval from 1:20 to 5:1 and from 7 to 60 wt % of the total amount of at least one disubstituted benzene, introduced at steps (a) and (d); (b) partial oxidation of at least one disubstituted benzene at the first oxidation step in the presence of a gas, containing molecular oxygen initially in amount of 3 to 20 vol. %, at temperature ranging from 121°C to 205°C and relative quantities of disubstituted benzene, catalytic metal, solvent and bromine, introduced at step (a), so that from 25 to 99.95 wt % disubstituted benzene, added at the first oxidation step, is oxidised with formation of a gaseous mixture, containing unreacted molecular oxygen, evaporated solvent and a first mixture of products, containing acid derivative, partially oxidised disubstituted benzene, unreacted disubstituted benzene and solvent, and at pressure from 8.96·105 to 14.8·105 Pa, sufficient for keeping disubstituted benzene, partially oxidised disubstituted benzene, acid derivative and solvent in liquid state or in form of a suspension of solid substance in a liquid, so that concentration of residual molecular oxygen in the remaining gaseous mixture ranges from 0.3 to 2 vol. %; (c) extraction of the obtained first product mixture after the first oxidation step and supplying at least part of the extracted first product mixture to the second oxidation step; (d) supplying gas to the second oxidation step, containing molecular oxygen and residue form total amount of disubstituted benzene, catalytic metal, solvent and bromine; (e) oxidation at the second oxidation step of partially oxidised disubstituted benzene and unreacted disubstituted benzene, supplied to the second oxidation step, with a gas containing molecular oxygen in amount of 15 to 50 vol. %, at temperature ranging from 175°C to 216°C and relative quantities of disubstituted benzene, partially oxidised disubstituted benzene, catalytic metal, solvent and bromine, introduced at step (a), so that from 96 to 100 wt % disubstituted benzene and partially oxidised disubstituted benzene is oxidised with formation of a gaseous mixture, which contains unreacted molecular oxygen, evaporated solvent and a second product mixture, containing acid derivative and solvent, and at pressure from 11.7·105 to 16.2·105 Pa so as to keep the acid derivative, partially oxidised disubstituted benzene and unreacted disubstituted benzene mainly in liquid state or in form of a suspension of solid substance in a liquid, so that concentration of residual molecular oxygen in the remaining gaseous mixture ranges from 3 to 15 vol. %; (f) extraction after the second oxidation step of the second product mixture, containing acid derivative; and (g) tapping gas which contains residual molecular oxygen after the second oxidation step and returning it to the first oxidation step.

EFFECT: method allows for maximum use of oxygen without reducing quality of the desired carboxylic acid using a stepped counterflow oxidation system.

25 cl, 11 tbl, 29 ex, 3 dwg

FIELD: chemistry.

SUBSTANCE: invention relates to a continuous stepped counterflow method of catalytic oxidation in a solvent of at least one benzene compound, containing two substituting groups, which are selected from alkyl, hydroxyalkyl, aldehyde, carboxyl groups and their mixtures, which can be oxidised to the corresponding acid derivative, involving the following steps: (a) introducing a mixture of material into the first oxidation step, containing at least part of the total amount of each of: (i) solvent, which is an organic acid, (ii) at least one catalytically active metal, selected from manganese, cobalt, nickel, zirconium, hafnium, cerium and their mixtures, and (iii) bromine in molar ratio, in terms of all catalytically active metals, in the interval from 1:20 to 5:1 and from 7 to 60 wt % of the total amount of at least one disubstituted benzene, introduced at steps (a) and (d); (b) partial oxidation of at least one disubstituted benzene at the first oxidation step in the presence of a gas, containing molecular oxygen initially in amount of 3 to 20 vol. %, at temperature ranging from 121°C to 205°C and relative quantities of disubstituted benzene, catalytic metal, solvent and bromine, introduced at step (a), so that from 25 to 99.95 wt % disubstituted benzene, added at the first oxidation step, is oxidised with formation of a gaseous mixture, containing unreacted molecular oxygen, evaporated solvent and a first mixture of products, containing acid derivative, partially oxidised disubstituted benzene, unreacted disubstituted benzene and solvent, and at pressure from 8.96·105 to 14.8·105 Pa, sufficient for keeping disubstituted benzene, partially oxidised disubstituted benzene, acid derivative and solvent in liquid state or in form of a suspension of solid substance in a liquid, so that concentration of residual molecular oxygen in the remaining gaseous mixture ranges from 0.3 to 2 vol. %; (c) extraction of the obtained first product mixture after the first oxidation step and supplying at least part of the extracted first product mixture to the second oxidation step; (d) supplying gas to the second oxidation step, containing molecular oxygen and residue form total amount of disubstituted benzene, catalytic metal, solvent and bromine; (e) oxidation at the second oxidation step of partially oxidised disubstituted benzene and unreacted disubstituted benzene, supplied to the second oxidation step, with a gas containing molecular oxygen in amount of 15 to 50 vol. %, at temperature ranging from 175°C to 216°C and relative quantities of disubstituted benzene, partially oxidised disubstituted benzene, catalytic metal, solvent and bromine, introduced at step (a), so that from 96 to 100 wt % disubstituted benzene and partially oxidised disubstituted benzene is oxidised with formation of a gaseous mixture, which contains unreacted molecular oxygen, evaporated solvent and a second product mixture, containing acid derivative and solvent, and at pressure from 11.7·105 to 16.2·105 Pa so as to keep the acid derivative, partially oxidised disubstituted benzene and unreacted disubstituted benzene mainly in liquid state or in form of a suspension of solid substance in a liquid, so that concentration of residual molecular oxygen in the remaining gaseous mixture ranges from 3 to 15 vol. %; (f) extraction after the second oxidation step of the second product mixture, containing acid derivative; and (g) tapping gas which contains residual molecular oxygen after the second oxidation step and returning it to the first oxidation step.

EFFECT: method allows for maximum use of oxygen without reducing quality of the desired carboxylic acid using a stepped counterflow oxidation system.

25 cl, 11 tbl, 29 ex, 3 dwg

FIELD: chemistry.

SUBSTANCE: invention relates to an improved method of producing basic phthalate of iron (III), which is used in chemical practice, analytical control and scientific research, through direct reaction of iron with atmospheric oxygen and phthalic acid in the presence of organic solvent, where the stimulating additive used is hydrochloric acid and inorganic chlorides in amount ranging from 0.013 to 0.062 mol/kg of the load. The liquid phase solvent is n-butyl alcohol iron which is crushed and moved in the reaction zone in form of steel balls with diametre ranging from 2.2 to 3.7 mm, alone or in combination with crushed cast iron in any mass ratio. Initial content of phthalic acid is varied from 1.0 to 1.5 mol/kg of the load. The reactor used is a vertical type bead mill with the grinding agent in form of steel balls and crushed alloy of iron together with glass beads in mass ratio of iron-containing reagent, beads and the rest of the load equal to 1:1:0.6 with a spill pipe as a bubbler during the process. Loading is done in the following sequence: grinding agent and moved metal, liquid phase solvent, phthalic acid, chlorine-containing stimulating agent, and the process itself starts with heating contents of the reactor to 35°, is carried out with self-heating in the range 35 to 50°C while stirring continuously, bubbling air at a rate of 2.3 to 3.1 l/(min kg of load), while maintaining temperature using a cooling liquid bath and controlling the process using a sampling method until exhaustion of all loaded acid, after which bubbling is stopped. Suspension of the reaction mixture is let to flow under gravity through a net lying in the field of a permanent magnet into the receiving tank of a vacuum filter, after which it is filtered. The residue is washed with the liquid phase solvent and taken for purification, and the primary filtrate and washing solvent are returned to the repeated process.

EFFECT: non-waste method at low temperature; wastes from other industries can be used as reagents; desired products can be separated by simple filtration.

2 cl, 8 ex

FIELD: chemistry.

SUBSTANCE: sodium hydroxide solution is added to a technical mixture of benzoic and cinnamylic acid, obtaining a precipitate. Water is added to obtain a homogeneous solution. The obtained technical mixture of sodium salts of benzoic and cinnamylic acid with composition ranging from 2:1 to 1:2 and overall concentration ranging from 3 to 5 M is then mixed with sulphuric acid with concentration ranging from 3 to 5 M. Addition of sulphuric acid is stopped at pH of the medium between 8 and 9, and the precipitated complex of cinnamylic acid with its sodium salt is filtered from the reaction mixture, dissolved in excess amount of water to dissolve sodium salt of cinnamylic acid. Cinnamylic acid precipitates, and is further treated with sulphuric acid with concentration ranging from 3 to 5 M to pH between 1 and 2. The precipitated crystals of cinnamylic acid are separated; the reaction mixture remaining after separation of the complex is mixed with a solution of sulphuric acid with concentration ranging from 3 to 5 M until pH between 1 and 2. As a result, crystalline benzoic acid forms.

EFFECT: formation of complexes of carboxylic acids with their sodium salts for separating components of a mixture of carboxylic acids with similar chemical and physico-chemical properties.

2 ex

FIELD: chemistry.

SUBSTANCE: invention refers to the improved method for oxidising of aromatic hydrocarbon such as para-xylol, meta-xylol, 2,6-dimethylnaphthalene or pseudocumene with forming of corresponding organic acid. The oxidation is implemented by the source of molecular oxygen in liquid phase at temperature range from 50°C to 250°C in the presence of catalyst being a) oxidation catalyst based on at least one heavy metal representing cobalt and one or more additive metals being selected from manganese, cerium, zirconium, titanium, vanadium, molybdenum, nickel and hafnium; b) bromine source; and c) unsubstituted polycyclic aromatic hydrocarbon. The invention refers also to the catalytic system for obtaining of organic acid by the liquid-phase oxidation of aromatic hydrocarbons representing: a) oxidation catalyst based on at least one heavy metal representing cobalt and one or more additive metals being selected from manganese, cerium, zirconium, titanium, vanadium, molybdenum, nickel and hafnium; b) bromine source; and c) unsubstituted polycyclic aromatic hydrocarbon.

EFFECT: activation of the aromatic hydrocarbons oxidation increasing the yield of target products and allowing to decrease the catalyst concentration and the temperature of the process.

45 cl, 4 tbl, 16 ex

FIELD: chemistry.

SUBSTANCE: invention refers to the improved method for oxidising of aromatic hydrocarbon such as para-xylol, meta-xylol, 2,6-dimethylnaphthalene or pseudocumene with forming of corresponding organic acid. The oxidation is implemented by the source of molecular oxygen in liquid phase at temperature range from 50°C to 250°C in the presence of catalyst being a) oxidation catalyst based on at least one heavy metal representing cobalt and one or more additive metals being selected from manganese, cerium, zirconium, titanium, vanadium, molybdenum, nickel and hafnium; b) bromine source; and c) unsubstituted polycyclic aromatic hydrocarbon. The invention refers also to the catalytic system for obtaining of organic acid by the liquid-phase oxidation of aromatic hydrocarbons representing: a) oxidation catalyst based on at least one heavy metal representing cobalt and one or more additive metals being selected from manganese, cerium, zirconium, titanium, vanadium, molybdenum, nickel and hafnium; b) bromine source; and c) unsubstituted polycyclic aromatic hydrocarbon.

EFFECT: activation of the aromatic hydrocarbons oxidation increasing the yield of target products and allowing to decrease the catalyst concentration and the temperature of the process.

45 cl, 4 tbl, 16 ex

FIELD: chemistry.

SUBSTANCE: claimed is group of inventions related to method of purification of flows of initial substances, containing aromatic compounds, in processes of polymerisation or alkylation by contact of flows of initial substances with zeolites, characterised by the fact that flow of initial substances is passed through, at least, two zeolites 1 and 2, average size of zeolite 1 pores being from 0.3 to 0.5 nm, and of zeolite 2 - from 0.6 to 0.8 nm, as well as to method of obtaining alkylated aromatic compounds by interaction of aromatic compounds with olefins on catalyst, which is characterised by the fact that flow of initial substances, containing aromatic compounds, is subjected to preliminary processing by described above method. Claimed method of purification of flows of initial substances, containing aromatic compounds, allows to prolong catalyst service life in processes of polymerisation and alkylation.

EFFECT: prolonging catalyst service life in processes of polymerisation and alkylation.

9 cl, 2 ex, 1 tbl

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