RU2264256C1 - Catalyst, method of preparation thereof and a method of isomerization of n-paraffins using this catalyst - Google Patents

Abstract

FIELD: petrochemical process catalysts.

SUBSTANCE: invention relates to catalytic methods of isomerizing n-paraffins and provides catalyst constituted by catalytic complex of general formula Me_xO_y*aAn^-*bC_nX_mH_2n+2-m, where Me represents group III and IV metal, x=1-2, y=2-3, An^- oxygen-containing acid anion, a=0.01-0.2, b=0.01-0.1; C_nX_mH_2n+2-m is polyhalogenated hydrocarbon wherein X is halogen selected from a series including F, Cl, Br, I, or any combination thereof, n=1-10, m=1-22, dispersed on porous carrier with average pore radius at least 500 nm and containing hydrogenation component. Method of preparing this catalyst is also disclosed wherein above-indicated catalytic complex is synthesized from polyhalogenated hydrocarbon C_nX_mH_2n+2-m wherein X, n, and m are defined above, group III and IV metal oxide, and oxygen-containing acid anion, and dispersed on porous carrier with average pore radius at least 500 nm, hydrogenation component being introduced either preliminarily into carrier or together with catalytic complex. Process of isomerizing n-paraffins utilizing above-defined catalyst is also described.

EFFECT: lowered isomerization process temperature and pressure and increased productivity of catalyst.

17 cl, 3 tbl, 25 ex

Description

The invention relates to the field of petrochemistry, and in particular to catalytic methods for the isomerization of normal paraffins.

The isomerization of normal paraffins contained in various hydrocarbon fractions of petrochemical industries is one of the most important processes ensuring the improvement of the quality of motor fuels in terms of energy and environmental indicators.

As a result of the isomerization reaction, normal C ₄ -C ₈ paraffins are converted, which, as a rule, have low indicators of the octane index, into iso-paraffins with a significant increase in the octane index.

The process of isomerization of n-butane provides an increase in the resource of oil refineries for isobutane - raw materials for the production of alkylate and methyl tert-butyl ether - environmentally friendly high-octane additives.

The process is carried out in the presence of various types of acid catalysts: aluminum chloride, chlorinated alumina, zeolites, sulfated metal oxides.

The stability of the action of the catalyst and the process is provided by introducing into the catalyst a hydrogenating additive, usually a Group VIII metal, and carrying out the process in the presence of hydrogen.

The process of isomerization of n-paraffins may be accompanied by the opening or narrowing of the cycle of naphthenic components, as well as the hydrogenation of aromatic hydrocarbons that may be present in the feedstock.

It is known that the value of the octane index is associated with the structure of the hydrocarbon skeleton of a hydrocarbon molecule. So, the value of the octane index for n-octane is 0, and for 2,2,4-trimethylpentane (isooctane) - 100.

Thermodynamic parameters of the paraffin isomerization process determine the predominant formation of the most branched paraffins at low temperatures, the most thermodynamically favorable temperature range of the isomerization process is in the range of 0-200 ° C. Therefore, the main studies are aimed at searching for catalysts for the isomerization of n-paraffins, which have high activity and selectivity for branched isomers in the indicated temperature range.

A known process for the isomerization of paraffins in the presence of chlorinated alumina (US Pat. US No. 4004859, F 01 D 25/00, 01/25/1977; US Pat. No. 4149993, C 07 C 5/30, 09/12/1978; US Pat. No. 6133496, C 07 C 5/22, 10/17/2000). In the presence of chlorinated alumina, high conversions of n-paraffins C ₄ -C _{6 are} achieved in the temperature range of the process 100-160 ° C. The conversion of n-butane at 142 ° С, a pressure of 31 atm, a ratio of Н ₂ / С ₄ equal to 0.05, a feed rate of n-butane of 4 g / g _cat * h, a concentration of chlorine-containing promoter of 170 ppm by weight of raw materials is 59- 62% with an isobutane selectivity of 99%, under similar conditions, the conversion of pentane and hexane is 75 and 88%, respectively. The selectivity for isopentane is 98.5%, for isohexanes - 98%. The total content of the most branched isomers of hexane - dimethylbutanes in the reaction products is 42-43 wt.%.

The disadvantages of this method of isomerization of n-paraffins in the presence of a catalyst based on chlorinated alumina is the sensitivity of the catalyst to impurities of sulfur, fluorine, alkaline compounds and water, which irreversibly deactivate the catalyst. As a consequence of this, there are increased requirements for the content of microimpurities in raw materials with respect to the concentrations of water, sulfur, fluorine and alkaline compounds, which should be 2-5 ppm.

A known method using zeolite catalysts for the process of isomerization of pentane-hexane hydrocarbon fractions (US Pat. US No. 5639933, C 07 5/22, 06/17/1997).

Medium-pore and wide-pore zeolites of the following structural types are usually used as catalysts: ZSM-5, mordenite, or Beta, which modify 0.3-0.5 wt.% Of platinum or palladium. The optimal temperature range of the isomerization process in the presence of mordenite or Beta zeolite is 200-270 ° C, ZSM-5 zeolite is 320-380 ° C. The isomerization process is carried out in the presence of 0.5-1 mol N ₂ / mol of raw materials. When carrying out isomerization of the pentane-hexane fraction on mordenite, the conversion of n-pentane is 72%, the conversion of n-hexane is 83%. The selectivity for isopentane is 97%, for isohexanes - 96%. The total content of the most branched isomers of hexane - dimethylbutanes in the reaction products is 39-40 wt.%. The catalyst is not sensitive to high concentrations of sulfur and water in the feed.

The disadvantage of these methods for the isomerization of n-paraffins in the presence of zeolite-based catalysts is the need to work in the high-temperature region, which is not thermodynamically favorable with respect to the formation of the most branched isomers having high values of the octane index.

The processes of isomerization of hydrocarbon fractions in the presence of catalysts based on sulfated metal oxides, mainly based on sulfated zirconium oxide modified with platinum, palladium, nickel, iron or manganese, are also known.

According to the method described in US Pat. US No. 5382731, С 07 С 1/00, 01/17/1995, it is known to use halogen-containing promoters, in particular carbon tetrachloride, for the process of isomerization of hydrocarbon mixtures containing cycloparaffins in order to increase the activity of the catalyst in the ring opening reaction using oxide-based catalyst systems zirconium modified with tungsten or molybdenum oxide.

In accordance with this method, the preparation of the catalyst consists of the following steps:

- precipitation of zirconium hydroxide from a solution of zirconium oxychloride with 10 N ammonia solution, followed by washing and drying the hydroxide at 140 ° C;

- application of tungsten oxide from a solution of ammonium metatungstate by moisture capacity in an amount of 11 wt.% with subsequent calcination of the sample at 800 ° C;

- application of platinum from a solution of chloroplatinic acid by moisture capacity, followed by drying and calcination at 300 ° C.

The resulting catalyst is used to convert a feedstock consisting of, wt.%: 50 - hexane, 14.5 - methylcyclopentane, 31.7 - cyclohexane, 3.9 - benzene at 260 ° C, pressure 30 atm, weight load of hydrocarbon feedstock on the catalyst 0.6 g / g _cat * hour, the ratio of H ₂ / feed = 2. The patent shows that the introduction of 700 weight ppm carbon tetrachloride into the reaction mixture leads to an increase in catalyst activity in the ring opening reaction of cycloparaffins by 10% from 38 to 48 wt.%.

The closest in technical essence and the achieved effect is a method for producing and using a solid acid catalyst (US Pat. US No. 6448198, B 01 J 27/053, 09/10/2002).

The preparation of the catalyst according to this method consists of several stages:

- two-fold application of zirconium oxychloride on alumina from an aqueous solution of zirconium oxychloride with intermediate calcination at 500 ° C;

- calcination of the obtained sample at 800 ° C;

- sulfation of the resulting material with a solution of 5N sulfuric acid;

- calcination of the obtained material at 500 ° C;

- modification of 0.3 wt.% platinum by impregnating the sample with a solution of hexachloroplatinic acid;

- calcination of the obtained material at 500 ° C.

The activity indicators of the catalyst are determined in the process of isomerization of n-hexane at 145 ° C, a pressure of 30 atm, a weight load on the catalyst of hexane of 4 g / g _cat * hour, the ratio of H ₂ / hexane = 3. The activity of the catalyst is evaluated by the content of 2.2 dimethylbutane in the reaction products, which under these conditions is 27-28 wt.%. The patent concludes that the activity of the catalyst is approximately consistent with industrial samples of chlorinated alumina isomerization catalysts.

Information on the conversion of hexane and the selectivity of the process in the patent is not given.

The disadvantage of this method is the complexity of the preparation of the catalyst, as well as the high consumption of hydrogen in the process of conversion of hydrocarbons.

The present invention solves the problem of creating an improved method for the process of isomerization of n-paraffins into isoparaffin fractions by lowering the temperature and pressure of the process, increasing the productivity of the catalyst prepared on the basis of sulfated metal oxides.

Improved compared with the prototype performance is achieved by:

- optimization of the porous structure of the carrier;

- optimization of the composition and distribution of the active component over the grain of the carrier;

- optimization of the nature and distribution of the hydrogenating component over the carrier grain;

- increasing the activity of the catalyst due to the synthesis of the catalytic complex of the active component and polyhalogenated on the surface of the catalyst.

In a number of works on the isomerization of n-paraffins (Adv. In Catalysis, 1969, v.23, 1969 pp. 369-372), it is noted that the activity of isomerization catalysts based on chlorinated alumina is significantly affected by the porous structure of the support, the preferred average pore radius The carrier must be at least 150 nm. As a result of chlorination of aluminum oxide, the average radius and total pore volume decrease, which leads to a decrease in the fraction of the active volume of the catalyst grain. Apparently, as a result of the deposition of the active component on the carrier in the case of dispersed sulfated metal oxides, a similar phenomenon of a decrease in the average radius and total pore volume is observed. So, after sulfation of zirconium oxide, a decrease in the fraction of wide pores of zirconium oxide and the formation of mesopores with an average radius of less than 100 nm are observed. This phenomenon is associated with the re-dissolution of the oxide in sulfuric acid and the formation of massive sulfate on the surface of the oxide.

In the present invention, metal oxides of groups III-IV, having a branched system of transport pores with an average diameter of about 500 nm, obtained by granulation of a microspherical amorphous oxide with an average particle diameter of 50-150 microns are used as an optimal carrier. The use of biporous metal oxides of groups III-IV with wide transport pores as a support or component of the catalyst allows to increase the fraction of the active volume of the grain of the catalyst and, therefore, increase its activity, especially in the process of isomerization of hydrocarbons with the number of carbon atoms greater than 5.

Typically, the distribution of the sulfate ion over the catalyst grain upon sulfation corresponds to the radial distribution of sulfate over the catalyst grain with a decrease in the concentration of sulfate towards the center of the grain. This leads to a non-optimal composition of the active component in the catalyst grain and impairs its activity.

In the present invention, a method for uniformly applying the active component to an alumina grain due to competitive sorption of sulfate from a solution of sulfuric acid on a carrier pre-treated with components whose sorption exchange capacity (SOE) is lower than that of a SOE of a sulfate ion, as well as a method for producing a catalyst by mixing and subsequent granulation of the active component and microspherical alumina, providing the formation of both the necessary porous structure of the catalyst, and uniform aspredelenie active component of the catalyst grain.

The uniform distribution of the hydrogenating component on the catalyst ensures the stability of the active component in the entire grain volume of the catalyst. To ensure a uniform distribution of the hydrogenating component, the method of competitive sorption of palladium and platinum on a support was used, followed by the synthesis of a sulfated oxide component on its surface.

The increased activity of the catalyst proposed in the present invention is the result of the formation of a catalytic complex, including sulfated metal oxide and polyhalogenated hydrocarbons, which can be various halogen-containing compounds, preferably carbon tetrachloride, perchlorethylene, chloroform. The formation of the complex occurs at low temperatures of 0-160 ° C; therefore, an increase in the activity of the catalyst as a result of processing it with 0.1-3 wt.% Halogenated hydrocarbons cannot be explained by chlorination processes occurring according to published data in the temperature range above 200 ° C. The activity of the obtained catalytic complex is comparable to the activity of aluminum chloride sublimated on chlorinated alumina.

Thus, the task is solved by the proposed catalyst composition for the process of isomerization of n-paraffins into isoparaffin fractions. The catalyst is a catalytic complex of the general formula: Me _x O _y · aAn ^- · b C _n X _m H _{2n + 2-m} , where Me is a metal of group III-IV, x = 1-2, y = 2-3, An ^{- the} anion of an oxygen-containing acid selected from the series: sulfuric, phosphoric, molybdenum, tungsten, or a mixture thereof in any combination, a = 0.01-0.2, b = 0.01-0.1; C _n X _m H _{2n + 2-m} - polyhalogenated hydrocarbon, where X-halogen selected from the series: F, Cl, Br, I or any combination thereof, n = 1-10; m = 2-22, dispersed on a porous carrier with an average pore radius of at least 500 nanometers and containing a hydrogenating component.

The porous carrier is an oxide of an element of groups III-IV, preferably Al; Si; Zr taken in an amount of 50-95 wt.% In relation to the catalytic complex.

The catalyst as a hydrogenating component may contain not more than 3.0 wt.%. Group VIII metal, preferably palladium or platinum, or any combination thereof.

The problem is also solved by the method of preparation of the catalyst, according to which the catalytic complex of the general formula: Me _x O _y · aAn ^- · b C _n X _m H _{2n + 2-m} , where Me is a metal of III-IV groups, x = 1-2, y = 2-3, An ^is an oxygen-containing acid anion selected from the series: sulfuric, phosphoric, molybdenum, tungsten, or a mixture thereof in any combination, a = 0.01-0.2, b = 0.01-0.1, C _n X _m H _{2n + 2-m} - polyhalogenated hydrocarbon, where X-halogen selected from the series: F, Cl, Br, I or any combination thereof, n = 1-10; m = 2-22, synthesized from an oxide or acidic, basic or neutral metal salt of groups III-IV and an oxygen-containing acid selected from the series: sulfuric, phosphoric, molybdenum, tungsten, or a mixture thereof in any combination, by impregnation or adsorption, or by mixing or their combination with a porous carrier with an average pore radius of at least 500 nanometers together with the hydrogenating component or the hydrogenating component is preliminarily introduced into the carrier, and the carrier thus obtained is heat treated at a temperature of not more than 800 ° C after uyuschim reduction of the hydrogenating component and introducing a polyhalo hydrocarbon at a temperature not exceeding 200 ° C.

The carrier is heat treated for no more than 15 hours. A porous carrier having a particle size of not more than 200 microns is used. The catalytic complex contains not more than 10 wt.% Polyhalogenated hydrocarbon synthesized by adsorption at a temperature of not more than 200 ° C for no more than 5 hours

An acidic, basic or neutral salt of a metal of group III-IV and an oxygen-containing acid selected from the series sulfuric, phosphoric, molybdenum, tungsten, or a mixture thereof in any combination, is introduced into the porous support in an amount of 2-30 wt.% With respect to the catalytic complex.

A porous support is used, which is an oxide of an element of groups III-IV, preferably Al; Si; Zr taken in an amount of 50-95 wt.% In relation to the catalytic complex.

Not more than 3.0 wt.% Group VIII metal, preferably palladium or platinum, or any combination thereof, is introduced into the catalyst as a hydrogenation component.

The problem is solved by the method of processing paraffin-containing oil fractions into isoparaffin fractions with an octane number of at least 84 by the motor method and a boiling end of not higher than 200 ° C, which consists in the conversion of normal structure C ₅ -C ₈ paraffins at a temperature of 30-200 ° C, mass load the initial mixture is 0.1-10 kg / kg _cat * hour, pressure 1-50 atm, in the presence of 0.2-10 wt.%. hydrogen and not more than 0.1 wt.% halogen-containing promoter, and as the catalyst using the catalyst described above, prepared according to the method described above.

The main distinguishing feature of the proposed method is that the isomerization of n-paraffins C ₅ -C _{8 is} carried out in the presence of a catalyst, which is a complex consisting of a polyhalogenated hydrocarbon of the general formula C _n X _m H _{2n + 2-m} , an acidic, basic or neutral salt a metal of group III-IV, an oxygen-containing acid selected from the series: sulfuric, phosphoric, molybdenum, tungsten, which are pre-heat treated at a temperature of 450-800 ° C for 0.5-15 hours, and a metal of group VIII.

The technical effect of the proposed method is that during the conversion of n-paraffins C ₅ -C _{8 of} normal structure at a temperature of 30-200 ° C, the mass load of the initial mixture is 0.1-10 kg / kg _cat * hour, pressure 1-50 atm., in the presence of 0.02-80 wt%. hydrogen and additionally a halogen-containing promoter in an amount of not more than 0.1 wt.% and in the presence of said catalyst isoparaffin fractions with an octane number of at least 84 are formed by the motor method and the boiling end is not higher than 180 ° C.

There are two options for implementing the method of preparation of the catalyst.

According to the first embodiment, an oxide, an acidic, basic or neutral metal salt of group III-IV groups, which are dispersed on a porous support by impregnation, are used as starting material for preparing the catalyst according to the proposed method. Next, the source material is heat treated at a temperature of 450-800 ° C. Acid anions — sulfate, phosphate, tungstate or molybdate, or a mixture thereof — are introduced into the material obtained by impregnation with a solution containing the corresponding acids or salts. The hydrogenating component (palladium or platinum, or a mixture thereof) is introduced either preliminarily onto a porous support or after heat treatment of the catalyst.

According to the second variant of the method, a solution containing a metal of group III-IV, a hydrogenating component — platinum or palladium, or a mixture thereof, an oxygen-containing acid anion is homogenized with a porous carrier having a particle size of 50-150 microns and granulated. The resulting catalyst is heat treated at a temperature of 450-800 ° C.

The catalyst prepared according to any of the options is placed in a flow reactor, purged with either nitrogen or hydrogen or an inert gas, after which hydrogen halide is fed at a temperature of 0-200 ° C at a rate of 10-1000 μl / g _cat * h. in a stream of hydrogen, nitrogen or inert gas at a speed of 50-1000 h ^-1 . Then hydrogen, a promoter and hydrocarbon feed at a flow rate of 0.1-10.0 h ⁻¹ , a molar ratio hydrogen / hydrocarbon feed of 0.1-10; temperature 20-200 ° С, pressure not more than 50 atm.

The invention is illustrated by the following examples.

Example 1. The preparation of the catalyst according to the first embodiment.

A. Application of palladium on alumina. 100 g of alumina (gamma form, average pore radius of 320 nanometers, nitrogen adsorption surface of 205 m ² / g, alkali metal oxide content of not more than 0.05 wt.%.) Is placed in a 2 liter glass, pour 500 ml of distilled water and with stirring add 1 ml of glacial acetic acid. A solution of palladium chloride obtained by dissolving 0.643 g of palladium chloride with a metal content of 59 wt.% In 3 ml of concentrated hydrochloric acid is diluted to a volume of 18 ml with distilled water and added dropwise to the aluminum oxide suspension with stirring over 1 hour. To complete the adsorption of palladium from The sample solution is stirred for 1 h.

After adsorption is complete, the sample is decanted and dried for 3 hours at a temperature of 130 ° C.

Calcined in a stream of air at a temperature of 750 ° C for 2 hours. Receive 98 g of aluminum oxide containing 0.39 wt.% Pd.

B. Sulphation of alumina modified with palladium. To 89 g of the sample obtained according to item A, 70 ml of a solution containing 19.5 g of 96% sulfuric acid in distilled water are added with stirring. The wet granules are dried in air to a free-flowing state, then at 200 ° C for 1 hour. They are calcined in a stream of air at 500 ° C for 2 hours. 102 g of sample are obtained with a sulfate content of 18.7 wt.%.

3.2 g of catalyst are loaded into an isothermal microreactor, palladium is reduced in a stream of hydrogen 375 h ^-1 at a temperature of 145 ° C, pressure 1 atm for 1 h. The synthesis of the catalytic complex on the surface of the catalyst is carried out by supplying 10 microliters of carbon tetrachloride to the reactor in a hydrogen flow of 375 h ^-1 at a temperature of 145 ° C, a pressure of 1 atm for 15 minutes, after which a mixture of hexane containing 10 ppm carbon tetrachloride and hydrogen taken in a molar ratio of 0.07 to hexane with a mass load of catalyst 4 h ^{- 1} hexane, at a temperature of 145 ° C, a pressure of 15 atm.

Analysis of the reaction products is carried out by gas chromatography on a capillary column DB1. From the gas chromatographic analysis, the conversion of hexane, the selectivity of the formation of dimethylbutanes and methylpentanes are calculated.

Get the following indicators of activity and selectivity of the catalyst.

The conversion of n-hexane,% 88.0 The selectivity of the formation of isomers of C6,% 99.1 The content of dimethylbutanes in the reaction products, wt.%. 41.3 The content of 2.2-dimethylbutane, wt.% 29.3.

From the obtained results it is seen that the process of isomerization of n-hexane in the presence of a catalytic complex composed of sulfated alumina and carbon tetrachloride leads to an increase in the activity of sulfated alumina to the level of activity of sulfated zirconium oxide, shown in the prototype.

Example 2

6.9 g of the catalyst of example 1 is loaded into an isothermal microreactor, palladium is reduced in a hydrogen stream of 375 h ^-1 at a temperature of 145 ° C, a pressure of 1 atm for 1 h, after which a mixture of hexane not containing carbon tetrachloride is fed to the reactor, and hydrogen, taken in a molar ratio of 0.07 with a mass load on the catalyst of 1 h ^-1 hexane, at a temperature of 145 ° C, a pressure of 15 atm. Get the following indicators of activity and selectivity of the catalyst.

The conversion of n-hexane,% 13.0 The selectivity of the formation of isomers of C6,% 99.9 The content of dimethylbutanes in the reaction products, wt.% 2,3 The content of 2.2-dimethylbutane, wt.% 1.1.

The results show that in the absence of a surface catalytic complex of carbon tetrachloride, the activity of the catalyst, expressed in the conversion of n-hexane, is 7 times lower.

Example 3

A. Application of palladium on alumina. 100 g of alumina (gamma form, average pore radius of 320 nanometers, nitrogen adsorption surface of 205 m ² / g, alkali metal oxide content of not more than 0.05 wt.%) Is placed in a 2 liter glass, 500 ml of distilled water are poured and 1 ml of glacial acetic acid is added with stirring. A solution of palladium chloride obtained by dissolving 0.643 g of palladium chloride with a metal content of 59 wt.%. in 3 ml of concentrated hydrochloric acid, diluted to a volume of 18 ml with distilled water and added dropwise with stirring to a suspension of alumina over 1 hour. To complete the adsorption of palladium from the solution, the sample was stirred for 1 hour. After completion of the adsorption, the sample was decanted and dried in for 3 hours at a temperature of 130 ° C. Calcined in a stream of air at a temperature of 750 ° C for 2 hours. Receive 98 g of aluminum oxide containing 0.39 wt.% Pd.

B. Application of zirconium oxide to alumina. A solution of 45.5 g of zirconium oxy nitrate in 70 ml of distilled water is applied in terms of moisture capacity to 89 g of the sample obtained according to item A, the sample is dried at 120 ° C for 2 hours and calcined at 600 ° C for 5 hours. 2 g of a sample with a zirconium oxide content of 11.2 wt.%.

B. Sulphation of Zirconia Supported on Palladium-Modified Alumina To 89 g of the sample obtained according to item B, 70 ml of a solution containing 22 g of 96% sulfuric acid in distilled water is added with stirring. The wet granules are dried in air to a free-flowing state, then at 200 ° C for 1 hour they are calcined in a stream of air at 500 ° C for 2 hours. 119 g of sample is obtained with a sulfate content of 15.9 wt.%.

2.1 g of the catalyst is loaded into an isothermal microreactor, the synthesis of the catalytic complex and the hexane isomerization process are carried out, as in Example 1, with a mass load of the catalyst of 6 h ^-1 on hexane, at a temperature of 135 ° C, a pressure of 12 atm. Get the following indicators of activity and selectivity of the catalyst.

The conversion of n-hexane,% 89.0 The selectivity of the formation of isomers of C6,% 99.0 The content of dimethylbutanes in the reaction products, wt.% 42.3 The content of 2.2-dimethylbutane, wt.% 33.3.

The results show that the isomerization process of n-hexane in the presence of a catalytic complex containing sulfated zirconia dispersed on alumina and carbon tetrachloride leads to an increase in the productivity of the isomerization process and the content of 2.2-dimethylbutane compared to the prototype.

Example 4

2.1 g of the catalyst of example 3 is loaded into an isothermal microreactor, the synthesis of the catalytic complex and the heptane isomerization process are carried out, as in example 1, with a mass load on the catalyst of 6 h ^-1 according to heptane, at a temperature of 110 ° C, a pressure of 12 atm, molar a hydrogen / heptane ratio of 0.5. Get the following indicators of activity and selectivity of the catalyst.

The conversion of n-heptane,% 97.0 The selectivity of the formation of isomers of C7,% 81.0.

Example 5

2.1 g of the catalyst of example 3 is loaded into an isothermal microreactor, the synthesis of the catalytic complex and the process of isomerization of octane are carried out, as in example 1, with a mass load on the catalyst of 6 h ^-1 octane at a temperature of 90 ° C, a pressure of 12 atm, a molar ratio hydrogen / heptane equal to 0.5. Get the following indicators of activity and selectivity of the catalyst.

The conversion of n-octane,% 97.0 The selectivity of the formation of isomers of C8,% 71.3.

Example 6

2.1 g of the catalyst of example 3 is loaded into an isothermal microreactor, the synthesis of the catalytic complex and the process of isomerization of hexadecane are carried out, as in example 1, with a mass load on the catalyst of 6 h ^-1 hexadecane, at a temperature of 90 ° C, a pressure of 12 atm, molar the ratio of hydrogen / hexadecane equal to 2. Get the following indicators of activity and selectivity of the catalyst.

The conversion of n-hexadecane,% 98.0 The selectivity of the formation of isomers With 16,% 12.3.

Example 7

2.1 g of the catalyst of example 3 is loaded into an isothermal microreactor, the synthesis of the catalytic complex and the process of isomerization of cyclohexane are carried out, as in example 1, with a mass load on the catalyst of 6 h ^-1 in cyclohexane, at a temperature of 100 ° C, a pressure of 12 atm and mol a hydrogen / cyclohexane ratio of 0.05. Get the following indicators of activity and selectivity of the catalyst.

The conversion of cyclohexane,% 48.0 The selectivity of the formation of isomers With 16,% 99.7.

Example 8

The preparation of the catalyst is carried out according to example 3, except that the intermediate sample prepared in part B of example 3 is treated with 300 ml of a solution containing 2.5 wt.% Hydrochloric acid for 3 hours, dried at 120 ° C. The result is 121 g of a sample with a sulfate content of 18.1 wt.%.

2.0 g of the catalyst is loaded into an isothermal microreactor, the synthesis of the catalytic complex and the hexane isomerization process are carried out, as in Example 1, with a mass load of the catalyst 6.1 h ^-1 in hexane, at a temperature of 120 ° C, a pressure of 10 atm. Get the following indicators of activity and selectivity of the catalyst.

The conversion of n-hexane,% 88.0 The selectivity of the formation of isomers of C6,% 99.6 The content of dimethylbutanes in the reaction products, wt.% 45.3 The content of 2.2-dimethylbutane, wt.% 34.6.

From the obtained results it is seen that the use of competitive sorption of sulfate in the preparation of the catalyst significantly increases its activity.

Example 9

2.0 g of the catalyst obtained in example 8 is loaded into an isothermal microreactor, the synthesis of the catalytic complex and the isomerization process are carried out as in example 8, except that n-hexane containing 0.008 wt.% Water is used to carry out the process 15 wt.% Thiophene sulfur. The process is carried out for 72 hours, after a drop in activity, the temperature of the reactor is increased to 160 ° C and purged with hydrogen at a speed of 400 h ^-1 for 2 hours, after which the isomerization process is again carried out under the conditions of example 8.

The activity and selectivity of the catalyst are shown in table 1

Table 1 Travel time, hour 10 52 72 10 The amount of feed, g / g cat 63 H ₂ O, g / g catalyst 0.005 0,026 0,036 0.005 The conversion of n-hexane,% 89 86 73 88 Isomerization Selectivity,% 99.8 99.9 99.9 99.7 The content of dimethylbutanes in the reaction products, wt.% 44.8 42.3 26.1 44.1 The content of 2.2-dimethylbutane in the reaction products, wt.% 33.9 30.7 14.2 32.1

From the obtained results it is seen that the catalytic complex is resistant to sulfur-containing impurities and water impurities in the feedstock, the activity of the catalytic complex is restored after heating of the reactor at a temperature of 150-170 ° C.

Example 10. The catalyst is prepared according to the second embodiment.

A. Preparation of a solution of the active component. 31.7 g of zirconium sulfate, 4.9 g of concentrated sulfuric acid are dissolved in 32 g of distilled water at room temperature for 5 hours, after the components are completely dissolved, 0.22 g of palladium chloride is added.

B. Preparation of the isomerization catalyst. The solution obtained in paragraph A is homogenized with 66.9 g of amorphous alumina, which is microspherical granules with an average diameter of 120 microns, an average pore radius of 510 nm, a nitrogen adsorption surface of 270 m ² / g, in the presence of 7.0 ml of a concentrated nitric solution acid and granulated by extrusion into granules with a diameter of 2 mm The granular catalyst was dried at 120 ° C. for 4 hours and calcined at 550 ° C. for 2 hours.

The resulting catalyst contains 11.0 wt.% Zirconium oxide, 21.3 wt.% Sulfate ion, 0.15 wt.% Palladium, the rest is aluminum oxide.

2.9 g of the catalyst are loaded into an isothermal microreactor, the synthesis of the catalytic complex and the isomerization process are carried out, as in example 8, except that the preparation temperature of the catalytic complex is 50 ° C, the process temperature is 70 ° C, the hexane load is 4 hours ^-1 . Get the following indicators of activity and selectivity of the catalyst.

The conversion of n-hexane,% 90.0 The selectivity of the formation of isomers of C6,% 99.8 The content of dimethylbutanes in the reaction products, wt.% 52.1 The content of 2.2-dimethylbutane, wt.% 37.6.

Example 11

The preparation of the catalyst is carried out as in example 10, except that instead of sulfuric acid, 4.23 g of zirconium oxychloride is used in the preparation of the solution of the active component. The resulting catalyst contains 11.0 wt.% Zirconium oxide, 18.3 wt.% Sulfate ion, 0.15 wt.% Palladium, the rest is aluminum oxide.

The isomerization process is carried out, as in example 10. Receive the following indicators of activity and selectivity of the catalyst.

The conversion of n-hexane,% 93.0 The selectivity of the formation of isomers of C6,% 99.3 The content of dimethylbutanes in the reaction products, wt.% 54,2 The content of 2.2-dimethylbutane, wt.% 39.6

Example 12

The isomerization process is carried out according to example 11, except that the process temperature is 120 ° C. Get the following indicators of activity and selectivity of the catalyst.

The conversion of n-hexane,% 96.0 The selectivity of the formation of isomers of C6,% 69.3 The content of dimethylbutanes in the reaction products, wt.% 34.2 The content of 2.2-dimethylbutane, wt.% 9.6

Example 13

The isomerization process is carried out according to example 11, except that the process temperature is 42 ° C. Get the following indicators of activity and selectivity of the catalyst.

The conversion of n-hexane,% 82.0 The selectivity of the formation of isomers of C6,% 99.9 The content of dimethylbutanes in the reaction products, wt.% 39.1 The content of 2.2-dimethylbutane, wt.% 28.3.

Example 14

The isomerization process is carried out according to example 11, except that the mass load of the catalyst on hexane is 6.3 h ^-1 . Get the following indicators of activity and selectivity of the catalyst.

The conversion of n-hexane,% 89.0 The selectivity of the formation of isomers of C6,% 99.7 The content of dimethylbutanes in the reaction products, wt.% 42.7 The content of 2.2-dimethylbutane, wt.% 31.4.

Example 15

The isomerization process is carried out according to example 11, except that the mass load on the catalyst for hexane is 1.0 h ^-1 . Get the following indicators of activity and selectivity of the catalyst.

The conversion of n-hexane,% 97.0 The selectivity of the formation of isomers of C6,% 89.1 The content of dimethylbutanes in the reaction products, wt.% 49.1 The content of 2.2-dimethylbutane, wt.% 29.6.

Example 16

The isomerization process is carried out as in example 11, except that the molar ratio of hydrogen / hexane is 4. Get the following indicators of activity and selectivity of the catalyst.

The conversion of n-hexane,% 81.0 The selectivity of the formation of isomers of C6,% 99.9 The content of dimethylbutanes in the reaction products, wt.% 49.1 The content of 2.2-dimethylbutane, wt.% 32.7.

Example 17

The isomerization process is carried out as in example 11, except that the molar ratio of hydrogen / hexane is 0.01. The following indicators of activity and selectivity of the catalyst are obtained.

The conversion of n-hexane,% 97.0 The selectivity of the formation of isomers of C6,% 65.9 The content of dimethylbutanes in the reaction products, wt.% 33.1. The content of 2.2-dimethylbutane, wt.% 16.7.

Example 18

The preparation of the catalyst is carried out according to example 11, except that instead of sulfuric acid in the preparation of a solution of the active component, 14.23 g of zirconium oxychloride is used. The resulting catalyst contains 11.0 wt.% Zirconium oxide, 5.3 wt.% Sulfate ion, 0.15 wt.% Palladium, the rest is aluminum oxide.

The isomerization process is carried out as in example 10. Receive the following indicators of activity and selectivity of the catalyst.

The conversion of n-hexane,% 74.0 The selectivity of the formation of isomers of C6,% 99.9 The content of dimethylbutanes in the reaction products, wt.% 17.9 The content of 2.2-dimethylbutane, wt.% 7.0.

Example 19

The isomerization process is carried out as in example 10, except that tetrachlorethylene is used to prepare the catalytic complex. Get the following indicators of activity and selectivity of the catalyst.

The conversion of n-hexane,% 91.0 The selectivity of the formation of isomers of C6,% 99.5 The content of dimethylbutanes in the reaction products, wt.% 53.9 The content of 2.2-dimethylbutane, wt.% 38.1.

Example 20

The isomerization process is carried out as in example 10, except that chloroform is used to prepare the catalytic complex. Get the following indicators of activity and selectivity of the catalyst.

The conversion of n-hexane,%, 88.0 The selectivity of the formation of isomers of C6,% 99.8 The content of dimethylbutanes in the reaction products, wt.% 41.3 The content of 2.2-dimethylbutane, wt.% 31.6.

Example 21

The isomerization process is carried out according to example 10, except that n-pentane is used as the raw material, and the process temperature is 80 ° C. Get the following indicators of activity and selectivity of the catalyst.

The conversion of n-pentane,% 83.0 The selectivity of the formation of isopentane,% 99.5.

Example 22

The isomerization process is carried out as in example 12, except that the hydrocarbon fraction of NK 21 ° C-KK 70 ° C is used as raw material.

The results are shown in table 2.

table 2 Raw materials, wt% Product, wt% C1-C4 5.7 6.2 Pentane 22.36 32.69 Isopentane 22.80 12.32 2.2-Dimethylbutane 1.43 6.93 2.3-Dimethylbutane 2.12 3.01 2-methylpentane 8.14 12.09 3-methylpentane 4.44 8.29 Hexane 10.64 6.63 C7 + 22.37 14.85

Example 23

The preparation of the catalyst is carried out according to example 3, except that instead of sulfuric acid, a solution of 14.3 g of phosphoric acid in 70 ml of water is used.

Isomerization of n-hexane is carried out under the conditions of example 3. Receive the following indicators of activity and selectivity of the catalyst.

The conversion of n-hexane,% 22.0 The selectivity of the formation of isomers of C6,% 99.9 The content of dimethylbutanes in the reaction products, wt.% 3.9 The content of 2.2-dimethylbutane, wt.% 1.3.

Example 24

The preparation of the catalyst is carried out according to example 3, except that instead of sulfuric acid, a solution of 14.3 g of ammonium metatungstate in 120 ml of water is used.

Isomerization of n-hexane is carried out under the conditions of example 3. Receive the following indicators of activity and selectivity of the catalyst.

The conversion of n-hexane,% 41.0 The selectivity of the formation of isomers of C6,% 99.9 The content of dimethylbutanes in the reaction products, wt.% 12,4 The content of 2.2-dimethylbutane, wt.% 5.4.

Example 25

The preparation of the catalyst is carried out according to example 3, except that instead of sulfuric acid, a solution of 17.0 g of ammonium metatungstate in 120 ml of water is used.

Isomerization of n-hexane is carried out under the conditions of example 3. Receive the following indicators of activity and selectivity of the catalyst.

The conversion of n-hexane,% 38,0 The selectivity of the formation of isomers of C6,% 99.9 The content of dimethylbutanes in the reaction products, wt.% 10.7 The content of 2.2-dimethylbutane, wt.% 3.1.

Thus, as can be seen from the above examples, the present invention allows to create an improved method for the isomerization of n-paraffins by lowering the temperature and pressure of the process, increasing the productivity of the catalyst.

Table 3 The composition of the catalysts and catalytic complexes of the isomerization process No. at
measure The composition of the catalytic complex, they say Catalytic
cue complex, wt.% The carrier, wt.% Group VII metal, wt.% Me _x Oh _y An ^- C _n X _m H _{2n + 2m} , 1 Al ₂ O ₃ 0.2 * SO ₄ 0.05 * CCl ₄ 24.61 Pd-0.39 Al ₂ O ₃ -75 2 Al ₂ O ₃ 0.2 * SO ₄ 0 24.61 Pd-0.39 Al ₂ O ₃ -75 3 ZrO ₂ 0.16 * SO ₄ 0.05 * CCl ₄ 26.61 Pd-0.31 Al ₂ O ₃ -73 4 ZrO ₂ 0.16 * SO ₄ 0.05 * CCl ₄ 26.61 Pd-0.31 Al ₂ O ₃ -73 5 ZrO ₂ 0.16 * SO ₄ 0.05 * CCl ₄ 26.61 Pd-0.31 Al ₂ O ₃ -73 6 ZrO ₂ 0.16 * SO ₄ 0.05 * CCl ₄ 26.61 Pd-0.31 Al ₂ O ₃ -73 7 ZrO ₂ 0.16 * SO ₄ 0.05 * CCl ₄ 26.61 Pd-0.31 Al ₂ O ₃ -73 8 ZrO ₂ 0.19 * SO ₄ 0.05 * CCl ₄ 34.85 Pd-0.15 Al ₂ O ₃ -65 nine ZrO ₂ 0.18 * SO ₄ 0.05 * CCl ₄ 35.85 Pd-0.15 Al ₂ O ₃ -65 10 ZrO ₂ 0.19 * SO ₄ 0.05 * CCl ₄ 34.85 Pd-0.15 Al ₂ O ₃ -65 eleven ZrO ₂ 0.12 * SO ₄ 0.05 * CCl ₄ 21.85 Pd-0.15 Al ₂ O ₃ -78 12 ZrO ₂ 0.12 * SO ₄ 0.05 * CCl ₄ 21.85 Pd-0.15 Al ₂ O ₃ -78 thirteen ZrO ₂ 0.12 * SO ₄ 0.05 * CCl ₄ 21.85 Pd-0.15 Al ₂ O ₃ -78 14 ZrO ₂ 0.12 * SO ₄ 0.05 * CCl ₄ 21.85 Pd-0.15 Al ₂ O ₃ -78 fifteen ZrO ₂ 0.12 * SO ₄ 0.05 * CCl ₄ 21.85 Pd-0.15 Al ₂ O ₃ -78 16 ZrO ₂ 0.12 * SO ₄ 0.05 * CCl ₄ 21.85 Pd-0.15 Al ₂ O ₃ -78 17 ZrO ₂ 0.12 * SO ₄ 0.05 * CCl ₄ 21.85 Pd-0.15 Al ₂ O ₃ -78 eighteen ZrO ₂ 0.05 * SO ₄ 0.05 * CCl ₄ 24.85 Pd-0.15 Al ₂ O ₃ -75 19 ZrO ₂ 0.19 * SO ₄ 0.05 * C ₂ Cl ₄ 34.85 Pd-0.15 Al ₂ O ₃ -65 twenty ZrO ₂ 0.19 * SO ₄ 0.05 * CHCl ₃ 34.85 Pd-0.15 Al ₂ O ₃ -65 21 ZrO ₂ 0.19 * SO ₄ 0.05 * CCl ₄ 34.85 Pd-0.15 Al ₂ O ₃ -65 22 ZrO ₂ 0.12 * SO ₄ 0.05 * CCl ₄ 21.85 Pd-0.15 Al ₂ O ₃ -78 23 ZrO ₂ 0.16 * PO ₄ 0.05 * CCl ₄ 26.61 Pd-0.31 Al ₂ O ₃ -73 24 ZrO ₂ 0.05 * WO ₄ 0.05 * CCl ₄ 28.85 Pd-0.15 Al ₂ O ₃ -71 25 ZrO ₂ 0.08 * WO ₄ 0.05 * CCl ₄ 31.85 Pd-0.15 Al ₂ O ₃ -68

Claims (17)

1. The catalyst for the process of isomerization of n-butane into isobutane, comprising a metal oxide of groups III-IV, an anion of oxygen-containing acid, characterized in that it is a catalytic complex of the general structure Me _x O _y * aAn ^- * b C _n X _m H _{2n + 2m} , where Me is a metal of groups III-IV, x = 1-2, y = 2-3, An ^- is an anion of an oxygen-containing acid selected from the series: sulfuric, phosphoric, molybdenum, tungsten, or a mixture thereof in any combinations, a = 0.01-0.2, b = 0.01-0.1; C _n X _m H _{2n + 2-m} - polyhalogenated hydrocarbon, where X is a halogen selected from the series: F, Cl, Br, I or any combination thereof, n = 1-10; m = 2-22, dispersed on a porous support with an average pore radius of at least 500 nm and containing a hydrogenating component. 2. The catalyst of claim 1, characterized in that the porous carrier is an oxide of an element of groups III-IV, preferably Al; Si; Zr taken in an amount of 50-95 wt.% In relation to the catalytic complex. 3. The catalyst according to claim 1, characterized in that the catalyst as a hydrogenating component may contain not more than 3.0 wt.% Metal of group VIII, preferably palladium or platinum, or any combination thereof. 4. A method of preparing a catalyst for the process of isomerization of n-paraffins into isoparaffin fractions, comprising metal oxide of groups III-IV, an anion of oxygen-containing acid, characterized in that the catalytic complex of the general formula Me _x O _y * aAn ^- * b C _n X _m H _{2n + 2-m} , where Me is a metal of group III-IV, x = 1-2, y = 2-3, An ^- is an oxygen-containing acid anion selected from the series: sulfuric, phosphoric, molybdenum, tungsten, or a mixture thereof in any combination, a = 0.01-0.2, b = 0.01-0.1, C _n X _m H _{2n + 2-m} is a polyhalogenated hydrocarbon, where X is a halogen selected from the series: F, Cl , Br, I or l bai combination thereof, n = 1-10; m = 2-22, synthesized from an oxide or acidic, basic or neutral metal salt of groups III-IV and an oxygen-containing acid selected from the series: sulfuric, phosphoric, molybdenum, tungsten, or a mixture thereof in any combination, by impregnation or adsorption, or mixing, or a combination thereof with a porous carrier with an average pore radius of at least 500 nm together with the hydrogenating component, or the hydrogenating component is preliminarily introduced into the carrier, heat treatment of the carrier thus obtained is carried out at a temperature of not more than 800 ° C, followed by the restoration of the hydrogenating component and the introduction of polyhalogenated hydrocarbon at a temperature of not more than 200 ° C. 5. The method according to claim 4, characterized in that the heat treatment of the carrier is carried out for no more than 15 hours 6. The method according to claim 4, characterized in that they use a porous carrier having a particle size of not more than 200 microns. 7. The method according to claim 4, characterized in that the catalytic complex contains not more than 10 wt.% Polyhalogenated hydrocarbon synthesized by adsorption at a temperature of not more than 200 ° C for no more than 5 hours 8. The method according to claim 4, characterized in that the acidic, basic or neutral salt of a metal of groups III-IV and an oxygen-containing acid selected from the series: sulfuric, phosphoric, molybdenum, tungsten, or a mixture thereof in any combination, is introduced into the porous carrier in the amount of 2-30 wt.% in relation to the catalytic complex. 9. The method according to claim 4, characterized in that a porous carrier is used, which is an oxide of an element of groups III-IV, preferably Al; Si; Zr taken in an amount of 50-95 wt.% In relation to the catalytic complex. 10. The method according to claim 4, characterized in that not more than 3.0 wt.% Group VIII metal, preferably palladium or platinum, or any combination thereof, is introduced into the catalyst as a hydrogenating component. 11. The method of isomerization of n-paraffins into isoparaffin fractions by contacting a hydrocarbon feed with a catalyst, characterized in that the catalyst according to any one of claims 1 to 10 is used as a catalyst. 12. The method according to claim 11, characterized in that an additional halogen-containing promoter in an amount of not more than 0.1 wt.% Is added to the hydrocarbon feed. 13. The method according to any one of claims 11 and 12, characterized in that fractions of paraffin and / or cycloparaffin hydrocarbons with a number of carbon atoms of at least 5 are used as hydrocarbon feedstock, the isomerization process is carried out at a temperature of not more than 200 ° C, the initial mass load mixtures of not more than 10 kg / kg _cat · h, pressure not more than 50 atm, in the presence of not more than 80 mol.% hydrogen. 14. The method according to any one of claims 11 and 12, characterized in that fractions of paraffinic and / or cycloparaffinic hydrocarbons with a number of carbon atoms of at least 5 and containing not more than 0.01 wt.% Water are used as hydrocarbon feedstocks for the isomerization process oxygen-containing compounds, not more than 0.15 wt.% sulfur compounds, not more than 0.0005 wt.% nitrogen compounds or alkaline compounds. 15. The method according to any one of claims 11 and 12, characterized in that pentane is used as a hydrocarbon feed for the isomerization process at a temperature of not more than 170 ° C, a mass load of the initial mixture of not more than 10 kg / kg _cat · h, pressure not more than 35 atm, in the presence of not more than 5 mol.% Hydrogen. 16. The method according to any one of claims 11 and 12, characterized in that hexane is used as a hydrocarbon feed for the isomerization process at a temperature of not more than 150 ° C, a mass load of the initial mixture of not more than 10 kg / kg _cat · h, pressure not more than 35 atm, in the presence of not more than 5 mol.% Hydrogen. 17. The method according to any one of claims 11 and 12, characterized in that cyclohexane is used as a hydrocarbon feed for the isomerization process at a temperature of not more than 150 ° C, a mass load of the initial mixture of not more than 10 kg / kg _cat · h, pressure not more than 35 atm, in the presence of not more than 5 mol.% Hydrogen.