WO2007091912A1

WO2007091912A1 - Method for producing motor fuel components

Info

Publication number: WO2007091912A1
Application number: PCT/RU2006/000066
Authority: WO
Inventors: Alexandr Sergeevich Bely; Alexandr Gennadievich Proskura; Dmitry Ivanovich Kiryanov; Mikhail Dmitrievich Smolikov; Vladimir Alexandrovich Likholobov
Original assignee: Institut Problem Pererabotki Uglevodorodov Sibirskogo Otdeleniya Rossiiskoi Akademii Nauk
Priority date: 2006-02-09
Filing date: 2006-02-09
Publication date: 2007-08-16

Abstract

The invention relates to producing high-octane motor fuel components and hydrogen from petrol and benzene fractions of gas-condensate and from C1 - C4 hydrocarbon gases. The inventive method consists in jointly processing the C1 - C4 hydrocarbon gases and benzene fractions in a system of reactors with a catalyst into C5+ motor fuel components; separating a water-containing gas from C5+liquid high-octane products; dividing the water-containing gas into hydrogen and C1 - C4 hydrocarbon gases by binding hydrogen in a reaction of catalytically hydrogenation of aromatic hydrocarbons into cyclohexane sequence hydrocarbons; recirculating the separated from hydrogen C1 - C4 hydrocarbon gases in a biforming reaction area for reprocessing them into C5+ liquid hydrocarbons; extracting the dissolved C1 - C4 hydrocarbon gases from C5+liquid products and recirculating them in the biforming reaction area for reprocessing into C5+ liquid hydrocarbons; removing excessive hydrogen from a process in the form of cyclohexane sequence hydrocarbons and/or a mixture thereof with the excessive C1 - C4 hydrocarbon gases and adding the C1 - C4 hydrocarbon gases extracted from the water-containing gas and from C5+liquid high-octane products and C3 - C5 hydrocarbon gases from an external source into the biforming recirculation area. The process is carried out in two stages, wherein the first stage consists in ageing the catalyst by the treatment thereof with C5+hydrocarbons at a temperature equal to or less than 480°C and the second stage consists in processing the mixture of benzene fractions and C1 - C4 hydrocarbon gases into the high-octane C5+ motor fuel components. The process is carried out on the base of a catalyst containing at least 0.5 mass% acidic components and at least 0-5 mass % metallic component , the rest up to 100 mass% being a carrier .

Description

A method of obtaining components of motor fuels.

The invention relates to the production of high-octane components of motor fuels, aromatic hydrocarbons and hydrogen from gasoline fractions of oil and gas condensate origin and C ₁ -C ₄ hydrocarbon gases and can be used in the oil refining and gas processing industries.

Known methods for processing gasoline fractions of oil boiling in the temperature range 62-190 ⁰ C, in high-octane components of motor fuels, aromatic hydrocarbons and hydrogen by catalytic reforming on catalysts containing platinum, chlorine and promoters on oxide carriers (G.P. Aptos, A. M. Aitapi, J.M. Rarera / Satalutis Narhtha Reformip. Sciepse apd Tespologu, Marcel Dekker Where, 1995).

The disadvantage of all known methods of reforming gasolines is the formation along with the target product (high-octane C ₅₊ reformate) of gaseous C ₁ -C ₅ hydrocarbons, the yield of which is 15-20% based on the feedstock.

There is also known a method for producing high-octane components of motor fuels by reforming gasoline fractions with two-stage separation of reaction products (US 4615793, ClOG 35/06, 1986). At the first stage of separation at elevated pressure and low temperature, hydrogen-containing gas (VGS), which is a mixture of hydrogen and C ₁ -C ₄ hydrocarbon gases, is separated from the C ₅₊ liquid reaction products. This gas is partially removed from the process, and part is returned to the process by mixing with the gasoline fraction at the inlet of the reforming reactor. In the second stage separation at a high temperature of C ₅₊ - Liquid product is separated depleted hydrogen-rich and C ₂ -C ₅ - hydrocarbon gas, which is recycled to the reaction zone for mixing with the feedstock. The disadvantage of this method is the low efficiency of the separation of hydrogen and hydrocarbon gases by the separation method, as well as the significant energy intensity of the process, due to the need to compress hydrocarbon gas from the separator of the second stage to the pressure in the reforming zone. In addition, this method does not significantly eliminate the conversion of the original liquid feed to low-value C ₁ -C ₄ hydrocarbon gases. As a result, the yield of the target high-octane liquid hydrocarbons is not more than 80-85 wt.% Calculated on raw materials.

Closest to the proposed is a method for the production of high-octane components of motor fuels - BIFOPMING-1 (RU 2144056, ClOG 63/02, 10.01.2000). The method includes biforming in the presence of a platinum-containing catalyst, followed by separation of liquid high-octane products and recirculation of C ₁ -C ₄ hydrocarbon gases to the biforming zone. The mixture of gases formed in the process (hydrogen and C ₁ -C ₄ hydrocarbon gases) is separated by binding (absorption) of hydrogen upon contact with aromatic hydrocarbons in the catalytic hydrogenation zone, after which the liquid hydrogenation products (cyclohexane hydrocarbons) are separated from C ₁ - C ₄ - hydrocarbon gases. The latter is recycled to the biforming zone. Ci-C ₄ - hydrocarbon gases are continuously recycled in a closed system from the hydrogenation zone to the biforming zone and vice versa without removing them from the process. An additional amount of Ci-C ₄ , a hydrocarbon gas from an external source, is supplied to the recycle gas stream. The hydrogen binding rate in the hydrogenation zone is maintained equal to the hydrogen evolution rate in the biforming zone. The hydrogenation products are divided into liquid (hydrocarbons of the cyclohexane series) and gaseous C ₁ -C ₄ hydrocarbons in a gas-liquid separator. Bound hydrogen in the form of cyclohexane hydrocarbons is removed from the process. Cyclohexane hydrocarbons are sent to the catalytic dehydrogenation zone. In the dehydrogenation zone at a temperature of 300-500 ⁰ C on a catalyst containing group VIII metal (s), cyclohexane-type hydrocarbons are converted to aromatic hydrocarbons and hydrogen. Hydrogen is separated from aromatic hydrocarbons in a separator and removed from the process. Aromatic hydrocarbons are sent to the hydrogenation zone continuously to bind the hydrogen released during the biforming process. Dissolved in liquid high-octane products C ₃ -C ₄ - hydrocarbon gases are released in a distillation column and returned to the reaction bedforming zone for mixing with the feed (gasoline fraction). C ₃ -C ₄ hydrocarbon gases dissolved in liquid cyclohexane hydrocarbons are separated by distillation and continuously recycled to mix with the liquid feed of the BIFOPMINGA-1 process. Thus, all generated in the process of C ₁ -C ₄ - hydrocarbon gases in the known method recycle in the reaction zone of the bioforming for recycling together with the liquid gasoline fraction.

The technical result achieved in the known method for the production of high-octane components of motor fuels, is to increase the yield of the target product and is achieved:

1. Due to the conversion of C ₁ -C ₄ - hydrocarbon gases into C ₅₊ - high-octane components.

2. By reducing the intensity of gas formation (hydrocracking) reactions of high molecular weight components of gasoline fractions.

Together, the implementation of the two above-mentioned effects provides an increase in the output of the high-octane component to 92-98 wt.% Based on the gasoline fraction fed to the processing.

A disadvantage of the known method for the production of components of motor fuels is the rather fast dynamics of a decrease in the activity of the catalyst, especially in the initial period of the reaction cycle with the simultaneous introduction of C ₁ -C ₄ hydrocarbon gases into the reaction zone along with the liquid feed (gasoline). The components of light hydrocarbon gases, co-adsorbing on the surface of the “fresh” catalyst, form strongly adsorbed hydrocarbon fragments that are nucleating agents of coke and cause premature deactivation of the catalyst, thereby reducing the yield of high-octane products.

These disadvantages are eliminated by the proposed method for the production of high-octane components of motor fuels, aromatic hydrocarbons and hydrogen. This problem is solved by conducting the biforming process in two stages. In the first stage, the catalyst is subjected to “storing” (running-in) under typical conditions of catalytic reforming of gasoline fractions in an amount of not less than 75 kg of fraction per kg of catalyst with the production of reformate with an ionic ion fraction of not more than 92 p. In this stage, the formation of hydrocarbon fragments occurs on the catalyst surface, which act as intermediates in the aromatization reactions of components of gasoline fractions. The presence of these hydrocarbons is a necessary condition for the conversion of C ₁ -C ₄ hydrocarbon gases into typical high-octane components in the second stage of the biforming process. Light hydrocarbon gases, co-adsorbing with heavier gasoline hydrocarbons, are part of a single transition complex and are converted into aromatic hydrocarbons and hydrogen. This eliminates the possibility of strong dissociative adsorption of light hydrocarbon gases, which on the surface of the "fresh" (unprocessed) catalyst is the cause of the deactivation and decrease in the efficiency of the biforming process.

In the second stage of the process, a mixture of gasoline fractions and C ₁ -C ₄ hydrocarbon gases is subjected to processing in a mass percentage of C ₁ -C ₄ ZC _{5+ of} at least 3 wt.% In C ₅₊ high-octane components of motor fuels. This achieves the technical result of the proposed method, which manifests itself in an increase in the stability of the catalyst and an increase in the yield of high-octane gasolines. The process in the second stage is carried out at a temperature of not less than 460 ⁰ C and a partial pressure of hydrogen of not more than 1.5 MPa.

Another significant feature of the proposed method for the production of high-octane components of motor fuels is the constant supply of water and an organochlorine compound to the reactor zone in the second stage in such a way that the moisture content of the SHG is in the range from 10 to 25 ppm.

It is known that the deactivation rate of catalysts for dehydrogenation processes depends on the ratio of the rates of formation and regeneration (hydrogenation) of strongly adsorbed hydrocarbon fragments of a high degree of dehydrogenation on the surface of the catalyst (coke precursors). One of the main conditions for good process stability is to ensure the equality of the rates of formation and hydrogenation of coke precursors on the catalyst [V. Durluakm, A. Velui, N. Ostrowski. Nef reformipat satellites of high resistapse to desivatiop // Nev Challepgers ip Catalysis. Serbiap Asademu of Scieps apd Arts. Nivi Sad. 1999. p. 89]. In turn, the rate of coke formation and hydrogenation depends on the amount and activity of hydrogen. By activity we mean the kinetic laws of activation and diffusion of (hydrogen) hydrogen over the surface, on which the rate of the self-regeneration process depends.

Simplified process of hydrogen activation can be represented as follows. The activation of molecular hydrogen occurs on the metal component of the catalyst. This process consists of the stages of adsorption, dissociation, surface diffusion and interaction with hydrocarbons. The rate of chemisorption and dissociation of hydrogen depends on the nature of the metal component. And the diffusion rate is determined by the degree of oxidation of the catalyst surface, which in turn is determined by the presence of oxidizing agents in the reaction zone. As such a substance in the proposed method, water is used in astoichiometric amounts, its content in the WASH from 10 to 25 ppm. Once in the reaction zone, water dissociates into hydrogen and oxygen. The latter oxidizes the surface of the catalyst at elevated temperatures. The degree of oxidation of the surface is determined by the water content in the reaction zone.

Thus, a continuous redox process (redox) is realized on the catalyst surface, the speed of which determines the diffusion rate of activated hydrogen over the surface and, as a result, the hydrogenation rate of coke precursors (catalyst self-regeneration rate).

However, the presence of water in the reaction zone leads to an increase in the rate of leaching of chlorine, which is contained in the acidic component bifunctional catalysts of the proposed method for the production of motor fuels.

In order to avoid the removal of chlorine from the catalyst composition in the proposed method, organochlorine compounds are constantly fed along with water to the reaction zone so that a lower H ₂ CVCl ratio is from 15 to 25. Under these conditions, the optimum hydrogen diffusion rates on the surface are reached and catalyst self-regeneration. This ensures high stability of the process in the second stage and, as a consequence, an increase in the production of high-octane components of motor fuels.

Another significant feature of the proposed method is the joint processing of C ₁ -C ₄ hydrocarbon gases and gasoline fractions on a catalyst containing, wt.%: Acid component of not less than 0.5 metal component, not less than 0.5 carrier, the rest to 100.

As an acid component, the catalyst may contain:

- aluminum hydroxide (SU 1019706, 01/22/1983);

- tin oxychlorides (SU 1210284, 10/08/1985);

- aluminum oxysulfates (RU 2050187, 12.20.1995);

- oxysulfates of metals of group IV of Ti, Zr, Hf.

As a metal component, the catalyst may contain elements of groups VII and VIII in the ionic state in the oxidation state n> 0 [Belui A.S. New Post Office of Surface Comsitiop of Reformipat Satellite. Reast. Lipet. Catal. Lettt, 1996, V.57, JN ° 2, ρ.349].

For example, as a metal component, the catalyst may contain rhenium and platinum in the form of surface sulfides ReS _x and PtS _y , where: x and y = 0.25-0.5.

As is known, elements of group VIII in the oxidation state of zero (metallic state) catalyze the conversion of hydrocarbons going through strongly adsorbed states in the direction of -CC- bond breaking (cracking and hydrogenolysis reactions). In contrast to metal forms, transformations on ionic forms go through less strongly bound intermediates in the directions of dehydrogenation, dehydroisomerization and dehydrocyclization, i.e. in the directions of the formation of typical high-octane components, to olefin and aromatic hydrocarbons (A.S. Bellui. Reformipt Саlаlusts оf tе PR Familu: Sіepіtifiс Foupdаtiops оf Рерарааtiсіпісіпісіпісіпісісіlаsіlаsіlаsіlаsіlаsіlаsіlаsіlаsіlаsіlаsіlаsіlаsіlаsіlаtіslаtісіlаsіlаsіlаsіlаsіlаsіlаt , p.728.)

As a carrier, the catalyst contains: aluminum oxide, aluminosilicates or mixtures thereof with a specific surface area of at least 200 m ² / g.

An essential distinguishing feature of the proposed method for the joint processing of C ₁ -C ₄ hydrocarbon gases and gasoline fractions is the use of a catalyst in which metal and acid components are present together.

The function of the metal component is to carry out dehydrocyclization reactions of alkane molecules. The function of the acid component is to weaken carbon-carbon bonds and to form dehydrogenated intermediates of extremely reactive carbon ions [Sauterfield CN. Neterohepeus Catalysis ip Pristise. McGraw-NS, Ips, 1980]. The function of the catalyst carrier is that it provides close contact between the acid and metal components and creates a developed mesoporous structure with a surface size of more than 200 m ² / g. Together, this structure ensures the availability of active components for reagents and removes diffusion inhibitions of reactions.

The combined supply of a mixture of light C ₁ -C ₄ - and heavy C ₅₊ - hydrocarbons leads to joint chemisorption of light and heavy molecules on active centers, their conjugate activation and, as a result, integration of light molecules into longer ones and their further transformation into isoparaffin and aromatic hydrocarbons. This process is carried out on the surface of the catalyst through a transition complex of light and heavy hydrocarbons, providing an increase in the efficiency of formation of high-octane components.

The effectiveness of the proposed method for the production of high-octane components of motor fuels is achieved by the method preparation of the catalyst, which provides the necessary chemical composition of the catalyst and the state of the components of the active phase.

The catalyst is prepared in two stages. In the first stage, the acid component is introduced into the catalyst by any known method, followed by drying and calcination of the obtained intermediate. The acid component is introduced either by mixing the corresponding compounds with aluminum hydroxide, followed by molding into extrudates, drying and calcining, or treating the formed and calcined support with solutions of the appropriate reagents, followed by drying and calcination. One of the essential conditions for obtaining high activity and selectivity of the catalyst is to obtain a defective crystalline structure of the acid carrier in the first stage of its preparation. This condition is provided by mixing aluminum hydroxide or a mixture of aluminum hydroxide and aluminosilicate clay with organic acids such as formic, acetic, oxalic, etc. In this case, organic aluminum salts are formed, which decompose during high-temperature calcination and form defects in the crystal structure of the acid support. The defect criterion is the true density of the carrier, which should be no more than 3.0-3.1 g / cm ³ . The presence of a defect in the crystal structure of the acid support is the main condition for the formation of ionic metal forms with an oxidation state of n> 0 in the second stage of preparation of the catalyst.

Metal components from among metals of groups VII and VIII of the group are introduced in the second stage of preparation of the catalyst by impregnation of the acid carrier with solutions of the corresponding compounds. A necessary condition for realizing the effects of strong metal-carrier interaction is the use of elevated (at least 80 ⁰ C) temperatures and competitor acids. The catalyst is then dried, calcined, reduced and sulphurized.

The amount of platinum group metals in the ionic state (oxidation state n> 0) is determined by the adsorption method described in [Veli AS, Kiruapov DI, Smolikov MD, et. al. O ₂ -adsorption apd (O ₂ -H ₂ ) -titration on electron deficient platinum in refonning catalysts. Kipet. Catal. Lett., 1994, V.53, M> l, p.l83].

The invention is illustrated by the following examples:

Example 1

Illustrates a known method of biforming C ₁ -C ₄ hydrocarbon gases and gasoline fractions into high-octane components of motor fuels.

The process is carried out at a bioforming unit, the basic technological scheme of which is shown in FIG. 1, where:

1 - biforming reactor;

2 - a separator for separating the WASH (H ₂ + C ₁ -C ₄ ) from C ₅₊ - liquid products;

3 hydrogenation reactor for binding H ₂ and separating it from C] -C ₄ ;

4 - methylcyclohexane dehydrogenation reactor to hydrogen and toluene;

5 - node separation of C ₃ -C ₄ - hydrocarbon gases from methylcyclohexane;

6 - node separation of C ₃ -C ₄ - hydrocarbon gases from C ₅₊ - unstable catalysis;

7 - a separator for the separation of hydrogen and toluene; AU - aromatic hydrocarbons;

TSU - hydrocarbons of the cyclohexane series (methylcyclohexane).

8, the reaction zone of the biforming reactor 1 is used with a reaction zone volume of 100 cm ³ . A polymetallic biforming catalyst of the following composition is loaded into the reactor, wt.%: Platinum - 0.25; rhenium - 0.3; chlorine - 1.0; the carrier (aluminum oxysulfate) - the rest is up to 100. In the hydrogenation reactor 3 and dehydrogenation 4 load the same catalyst in an amount of 25 cm ³ each. Before starting the process, the catalysts in each reactor are reduced with hydrogen at 500 ^° C, a pressure of 1.0 MPa, and a hydrogen feed rate of 10 nl / h. The raw material for the process is a mixture of n-butane (3.0 wt.%) And a gasoline fraction of 105-185 ⁰ C (100 wt.%) With a density of 0.743 g / ml, which are mixed with a hydrogen-containing gas and fed to the reaction bedforming zone at a temperature 495 ⁰ C and a pressure of 2.2 MPa at a rate of 150 ml / h. The reaction products from reactor 1 are cooled and served in the separator 2. Hydrogen (80 vol.%) and light hydrocarbon gases from the separator 2 are fed into the hydrogenation reaction zone 3, which also serves toluene at a rate of 62 ml / h. In a hydrogenation reactor in the presence of a catalyst at a temperature of 250 ⁰ C and a pressure of 2.2 MPa, hydrogen gas is separated from C ₁ -C ₄ gases by entering into the composition of methylcyclohexane formed during hydrogenation. The reaction products are cooled and fed to a separator 5. Here, due to the large difference in the boiling points of methylcyclohexane and C ₁ -C ₄ hydrocarbon gases, they are separated. Hydrocarbon gases and part of the unreacted hydrogen are recycled to the biforming zone to mix with the continuously supplied gasoline fraction 105-185 ⁰ C. Liquid C ₅₊ hydrocarbons are sent for stabilization to distillation column 6, in which products are separated into C ₃ -C ₄ liquefied gases and stable high octane catalysis. The catalyst is continuously withdrawn from the process, and liquefied gases are recycled to the inlet of the bioforming reaction zone.

Methylcyclohexane containing chemically bound hydrogen is subjected to dehydrogenation in reactor 4 at a temperature of 500 ⁰ C, with the formation of toluene and hydrogen in a molar ratio of 1: 3. Dehydrogenation products are separated into hydrogen and toluene in a separator 7. Hydrogen is removed from the process. The purity of hydrogen is above 97 vol.% Liquid toluene is returned to the hydrogenation zone to separate hydrogen from C ₁ -C ₄ hydrocarbon gases from the biforming zone.

Thus, the basic principle of the biforming process is implemented, which consists in the fact that the hydrocarbon C ₁ -C ₄ gases formed in the process are not completely removed from the process as low-value by-products, but are intensively recycled to the reforming reaction zone, where they enter into joint transformations with macromolecular components of gasoline with the formation of high-octane components of motor fuels. At the same time, the main technical result of the biforming process is achieved, consisting in increasing the yield of the high-octane component to 92 wt.% Or more, based on the straight-run gasoline fraction submitted for processing. In FIG. 2 shows the data on the yield of octane-increasing aromatic hydrocarbons in the course of biforming for 100 hours, where:

1. A known method of biforming - example N ° 1;

2. The proposed - example N ° 2;

3. For comparison - an example of JYoZ.

From the data presented in FIG. 2, it follows that when a mixture of hydrocarbon gases and gasoline is fed to the biforming reactor on a fresh catalyst (curve 1) at a temperature of 495 ⁰ C, a rather fast dynamics of a decrease in the activity of the catalyst is observed. The yield of aromatic hydrocarbons during the first day of the process is reduced from 65 wt.%. up to 59 wt.% This indicates that the supply of hydrocarbon gases to the fresh surface of the catalyst leads to intensive deactivation of the catalyst. This disadvantage is eliminated by the proposed method for the joint processing of C ₁ -C ₄ hydrocarbon gases and gasoline fractions.

Example 2. Illustrates the proposed method for the production of high-octane components of motor fuels, a catalyst and a method for its preparation.

In the process, a catalyst of the following composition is used, wt.%: Acid component (ZrOSO ₄ ) - 0.65 metal component - 0.6 including: ionic platinum - 0.24 metal platinum - 0.06 rhenium - 0.3 carrier ( alumina) up to 100.

The catalyst is prepared in two stages.

The acid component is introduced into the catalyst by mixing a solution of a salt of sulfatocirconyl in acetic acid with aluminum hydroxide (modification of pseudoboehmite). The ratio of acetic acid / AUON is 0.02 (calculated on calcined alumina). The mixture is dried with stirring to a moisture content of 58 wt.%, Molded in stiffeners with a diameter of 2 mm, dried to a moisture content of 20 wt.%, calcined to a moisture content of 1.0 wt.%. The true density of the product is 3.1 g / cm ³ .

In the second stage, the carrier is evacuated to a residual pressure of 0.01 VΙPa and moistened with water (80 ml of water per 100 g of carrier). Then the carrier is treated with 60 ml of an aqueous solution containing 0.3 g of platinum in the form of platinum chloride, 0.3 g of rhenium in the form of HReO ₄ , 0.6 g of polar acid. The carrier is treated for 1 h at a temperature of 30 ⁰ C, and then 1 h at 80 ⁰ C. 0.03 g of oxalic acid and 0.15 g of hydrogen peroxide are added to the impregnation solution. Processing is continued for 0.5 hours with stirring. Then the solution is drained, the catalyst is dried at 120 ⁰ C to a moisture content of 12 mass%, calcined to a moisture content of 2.0 mass%, reduced with hydrogen at 500 ⁰ C and grained with hydrogen sulfide at the rate of S / Pt = 0.5 (mol).

The catalyst is loaded into the reactor 1 in an amount of 100 cm ³ . In the hydrogenation reactor 3 and dehydrogenation 4 load the catalyst of example 1.

The process of obtaining components of motor fuels is carried out in two stages.

In the first stage, the catalyst is run-in (aging) by feeding into the reactor 1 a mixture of a gasoline fraction (with a space velocity of 1.5 h ^"1 ) and hydrogen (once the system is filled with hydrogen to a pressure of 1.0 MPa) at a temperature of 400 ⁰ C. In these Under conditions, aromatization reactions of naphthenic hydrocarbons begin to take place.The resulting hydrogen and hydrocarbon gases are removed from the process.The temperature is gradually raised to 460 ⁰ C (in 6 hours), and then to 480-485 ⁰ C in 10-12 hours. surface hydrocarbon fragment nt, which act as intermediates in the formation of isoparaffin and aromatic hydrocarbons. The aging process of the active surface is slow and it takes at least 24-36 hours to complete it, which is equivalent to processing at least 75 kg of raw materials per kg of catalyst. The criterion for completing the aging process of the catalyst is stabilization of parameters the content of aromatic hydrocarbons in liquid products and their octane numbers. The optimal parameters of the aging mode of the catalyst is the reformate production mode with an octane number of IOI not more than 93p., Which is achieved when the content of aromatic hydrocarbons up to 63 wt.% at temperatures of 480-485 ⁰ C. Then they proceed to the second stage of the biforming process, organizing the recirculation of C ₁ -C ₄ hydrocarbon gases from separator 5 and C ₃ - C ₄ liquefied gases from separator 6 (Fig. 1) into the reaction zone of the biforming - into the reactor 1.

The burned-in surface of the catalyst contains hydrocarbon intermediates of the aromatization reaction, which prevent the deep dehydrogenation of C ₃ -C ₄ alkanes and contribute to their conversion under conditions of joint conversion with gasoline into high-octane components of motor fuels. Under these conditions (curve 2, Fig. 1), the process proceeds stably, which ensures the goal of the proposed method is to increase the production of aromatic hydrocarbons, which are the main octane-raising components of motor fuels. Stable operation of the catalyst is also ensured by the fact that water and an organochlorine compound from among dichloroethane, trichlorethylene, carbon tetrachloride are continuously pumped into the feed stream to the inlet of the reactor 1. The water feed rate is maintained such that the moisture content of the WASH from the separator 2 is 10-25 ppm, and the molar ratio of H ₂ CVCl is in the range of 15-25. This operation is necessary to maintain at an optimal level the acid function of the catalyst during continuous operation in the conditions of the bioforming reaction cycle. If the supply of water and chlorine to the reaction zone is absent (examples 1-3), as well as when the moisture content of the WASH is more than 25 ppm (example 5), the efficiency of the biforming process is reduced. The main parameters and results of the proposed method are shown in the table.

The average yield of high-octane component (BOK) under optimal conditions is 95 wt.% Calculated on the gasoline fraction with an octane number of IOC of 99.3 p., Which indicates the achievement of the objectives of the present invention.

Example 3. Illustrates the influence of the conditions of the aging stage of a fresh catalyst.

The aging (running-in) method is carried out as in Example 2, with the difference that the aging time is reduced from 50 hours to 25 hours (from 75 kg to 50 kg of raw material per 1 kg of catalyst) and, in the final stage of aging, the conditions provided a more stringent mode compared with example 2. At a temperature in the reactor of 1,485 ^° C, the octane number was 98 p. with an aromatic hydrocarbon content of 69.5 wt.%. Therefore, the most optimal conditions for the aging of the catalyst is the mode with the production of BOK with an octane number of IOC no more than 93 p. In the amount of not less than 75 kg per 1 kg of catalyst.

Example 4. Illustrates the influence of process temperature on the yield and characteristics of the obtained high-octane product in the joint processing of C ₁ -C ₄ hydrocarbon gases with gasoline.

The processing method is the same as in example 2 with the difference that the processing is carried out in the bioforming reactor 1 (Fig. 1) at a temperature of 460 ⁰ C. In this case, the octane number of the IOC is 91 p. With the content of aromatic hydrocarbons on May 58. % Therefore, the aim of the invention is achieved by carrying out the process at reaction temperatures of more than 460 ⁰ C.

Example 5. The method is carried out as in example 2 with the difference that water is supplied to the biforming zone in an amount of 20 ppm, and chlorine in an amount of 0.5 ppm, based on raw materials. The humidity of the WASH is 30 ppm, and the ratio of H ₂ O / C1 is more than 40. From the table it follows that when carrying out the process in conditions of high humidity (more than 25 ppm) and with insufficient amounts of chlorine supplied to the system, the efficiency of the biforming process decreases. The yield of BOK compared with example 2 is reduced from 95.0 wt.% To 92.8 wt.%, And the octane number of the IOC from 99.3 p. To 97 p.

Example 6. Illustrates the decrease in the efficiency of the bioforming process while reducing the amount of C ₁ -C ₄ hydrocarbon gas fed to the processing from 3 wt.% To 1.5 wt.%.

Processing a mixture of Ci-C ₄ hydrocarbon gases and gasoline fraction is carried out according to example 2 with the difference that the amount of gas supplied to the processing from an external source decreases from 3 wt.% To 1.5 wt.% With respect to the gasoline fraction. In this case, the BOK yield decreases from 95 wt.% To 91.5 wt.% ₅ and the octane number from 99.3 p. To 96.5 p. Example 7. Illustrates the effect of reducing in the composition of the catalyst an acid component of less than 0.5 wt.% And a metal component of less than 0.5 wt.%.

In the process, a catalyst of the following composition is used, wt.%: Acid component (ZrOSO ₄ ) - 0.3; metal component Pt ⁺ - 0.3; carrier (aluminum oxide) - the rest is up to 100.

The catalyst is prepared in two stages. The acid component is introduced by mixing a solution of a zirconyl sulfate salt (0.3 g of salt per 100 g of aluminum oxide) in acetic acid with aluminum hydroxide (modification of pseudoboehmite). The ratio of acetic acid / AlOOH is 0.02. The mixture is dried with stirring to a moisture content of 60 wt.%, Molded into extrudates d = 2.0 mm, dried to a moisture content of May 20. %, calcined to a moisture content of 1.0 wt.%. In the second stage, the acid carrier is evacuated to a residual pressure of 0.01 MPa and moistened with water (80 g of water per 100 g of aluminum oxide). Then the carrier is treated with 60 ml of an aqueous solution containing 0.3 g of platinum in the form of platinum chloride hydrochloric acid and 1.0 g of hydrochloric acid. The carrier is treated with the solution with stirring for 1 h at a temperature of 30 ⁰ C, and then 1 h at 80 ⁰ C. 0.03 g of oxalic acid and 0.15 g of hydrogen peroxide are added to the impregnation solution. Processing is continued for 0.5 hours. After this, the solution is drained, the catalyst is dried at 120 ^° C to a moisture content of 12 mass%, calcined to a moisture content of 2.0 mass%, reduced with hydrogen at 500 ^° C, and sulfonization is carried out at the rate of S / Pt = 0.5 (mol).

The process is carried out as in example 2. The results of the process are shown in the table. From these results it follows that the use in the proposed method of a catalyst with an acid and metal component content of less than 0.5 wt.% Each leads to a decrease in the yield of BOK from 95 wt.% To 92.5 wt.% And the octane number from 99.3 to 95 p.

Example 8. Illustrates the proposed method using a catalyst of the following chemical composition, wt.%: Acid component AlOHCl ₂ - 2,3; metal component - 0.6; including Pt ⁺ - 0.3;

Pd ⁺ - 0.3; the carrier (aluminum oxide) - the rest is up to 100. The catalyst is prepared in two stages.

The acid component is introduced into the catalyst in the first stage in a known manner (SU 1019706, 01/22/1983).

To prepare the acid component, 100 g of aluminum oxide is treated with a solution containing 7 g of hydrogen chloride dissolved in isopropyl alcohol. The interaction of hydrogen chloride with alumina is carried out in the mode of circulation of the solution through the carrier layer at room temperature for 2 hours. Then the solution is separated, the carrier is dried and calcined at 500 ⁰ C to a residual moisture content of 2.0 wt.%. The product contains 7.0 wt.% Chlorine and corresponds to the formula Al ₁₉ O ₂₃ AlOHCl ₂ .

In the second stage, the carrier is evacuated to a residual pressure of 0.01 MPa and moistened with water (80 g of water per 100 g of aluminum oxide). The carrier is then treated with 60 ml of an aqueous solution containing 0.3 g of platinum in the form of platinum chloride, 0.3 g of palladium in the form of palladium chloride and 0.8 g of hydrochloric acid. The carrier is treated for 1 h at a temperature of 25 ⁰ C, and then 1 h at 80 ⁰ C. The solution is drained, the catalyst is dried, calcined, reduced with hydrogen at 500 ⁰ C and grained with hydrogen sulfide at the rate of S / Pt = 0.5 (mol).

The biforming process is carried out under the conditions given in the table. In the experiment 1, water is continuously fed into the reactor 1 to maintain the WAG humidity at 25 ppm and dichloroethane to maintain a water / chlorine molar ratio of 25.

This example illustrates the possibility of reducing the process pressure from 2.2 MPa to 0.5 MPa.

Example 9. Use the catalyst of the following composition, wt.%: Acid component SnOCl ₂ - 1,1; metal component - 0.6, incl. Pt ⁺ - 0.3,

Pd ⁺ - 0.3, carrier (alumina) - the rest is up to 100. The acidic component is introduced into the composition of the catalyst in a known manner (SU 1210284, BOlJ 23/62, 04/23/1984). 27 g of aluminum metal are dissolved in HO ml of a 10% hydrochloric acid solution. The resulting solution is neutralized with a 10% sodium hydroxide solution to pH = 8-9 and mixed with 0.6 g of tin tetrachloride per metal. The precipitate is washed, formed at a moisture content of 60% in May. into extrudates, dried and calcined at 630 ⁰ C.

100 g of the obtained carrier are treated with 350 ml of a solution containing 6.4 g of hydrogen chloride. The carrier is dried and used to prepare the catalyst. The carrier corresponds to the general formula Al ₂₀ O ₂₉ (SnO ₂ Cl ₂ ) _{0) 05} .

The preparation of the catalyst in the second stage is carried out according to example 2. The biforming process is carried out under the conditions shown in the table. Water is continuously fed into the biforming reactor to maintain a Wash moisture content of 10 ppm and trichlorethylene to maintain a water / chlorine molar ratio of 15.

This example illustrates the possibility of obtaining the proposed method a high-octane component with an octane number of IOI more than 100 p.

Example 10. Use the catalyst of the following composition, wt.%: Acid component AlOSO ₄ - 4.3; metal component - 0.6, incl. Pt ⁺ - 0.3,

Re is 0.3; the carrier is the rest up to 100, alumina 80, aluminosilicate clay (montmorillonite) 20. The catalyst is prepared in two stages.

Aluminum oxysulfate is prepared in a known manner (RU 2050187, BOlJ 23/656, 12.20.1095).

In the first stage, aluminum hydroxide (80 g per aluminum oxide) is mixed with 20 g of montmorillonite (in terms of calcined aluminosilicate) and with 3.0 g sulfuric acid at 20 ^° C adding 8.2 ml of acetic acid. The mass is formed into granules, dried and calcined at 580 ^° C. Under these conditions, oxysulfate of the composition Al ₁ C) Oa ₇ (AlOSO ₄ ) _O132 with a sulfate ion content of 3.0 mass% is formed.

The second stage of preparation of the catalyst is carried out according to example 2.

The biforming process is carried out under the conditions given in the table.

The process provides obtaining BOK with an octane number of IOI 103 p. With the release of 98.8 wt.%.

Example 11. The process is carried out in a system of three reactors.

The reactions of formation of high-octane components of motor fuels, including aromatic hydrocarbons, under biforming conditions have a large endothermic effect, which causes the appearance of a temperature gradient along the length of the catalyst bed, as a result of which the catalyst at the reactor outlet is at a lower temperature than at the inlet reactor. This reduces the efficiency of the biforming process. Using the same amount of catalyst 100 cm, but loading in three successively smaller reactors with intermediate heating of the reaction mixture to a predetermined temperature, significantly increases the efficiency of the process. This is manifested in the achievement of high performance at lower temperatures.

Example 12. The process is carried out as in example 11, but with the difference that it is carried out in reactors with a radial flow of the mixture through the catalyst bed in the direction from the center to the periphery of the reactor. In this case, a decrease in temperature along the catalyst bed due to the endothermic effect of the reaction is compensated by a decrease in the space velocity (increase in contact time) as a result of an increase in the catalyst volume as the flow moves from the center of the reactor to the periphery. In this embodiment, the efficiency of the process increases (table). This is manifested in the achievement of high performance at even lower temperatures. Indicators and results of the production process of high-octane components (BOK) of motor fuels

Claims

CLAIM

1. A method of producing components of motor fuels from C ₁ -C ₄ hydrocarbon gases and gasoline fractions in the presence of a platinum-containing catalyst, including:

- joint processing of C ₁ -C ₄ hydrocarbon gases and gasoline fractions in a reactor system with a catalyst in C ₅₊ - components of motor fuels;

- separation of hydrogen-containing gas from liquid high-octane products

- C ₅ +;

- separation of the hydrogen-containing gas into hydrogen and C ₁ -C ₄ hydrocarbon gases by hydrogen bonding by the catalytic hydrogenation of aromatic hydrocarbons into hydrocarbons of the cyclohexane series and by recycling C ₁ -C ₄ hydrocarbon gases separated from hydrogen to the bioforming reaction zone for recycling to C _{5 +} - liquid hydrocarbons;

- the allocation of C ₅₊ - liquid products of dissolved C ₃ -C ₄ - hydrocarbon gases and their recirculation to the reaction zone of the bioforming for recycling in C ₅₊ - liquid hydrocarbons;

- removal from the process of excess hydrogen in the form of hydrocarbons of the cyclohexane series and / or in a mixture with excess amounts of C ₁ -C ₄ hydrocarbon gases;

- the addition of C ₁ -C ₄ - hydrocarbon gases extracted from the hydrogen-containing gas and C ₅₊ - liquid high-octane products to the recirculating to the bi-forming zone, C ₃ -C ₅ - hydrocarbon gases from an external source, characterized in that the process is carried out in two stages where in the first stage the catalyst is aged by treating it with C ₅₊ hydrocarbons in an amount of at least 75 kg per 1 kg of catalyst at a temperature of not more than 48 ⁰ C, and in the second stage, the mixture of gasoline fractions and C ₁ -C ₄ - is processed hydrocarbon gases in mass percent ohm ratio C ₁ -CVC ₅₊ at least 3% in the C ₅₊ - high-octane component of motor fuels.

2. The method according to claim 1, characterized in that the process in the second stage is carried out at a temperature of more than 460 ⁰ C.

3. The method according to claim 1, characterized in that during the second stage of the process, water and an organochlorine compound are constantly supplied to the bioforming reaction zone in such a way as to maintain the moisture content of the hydrogen-containing gas in the range of 10-25 ppm, and the molar ratio of H ₂ O / C1 within 15 - 25.

4. The method according to claim 1, characterized in that the processing of the mixture of C ₁ -C ₄ hydrocarbon gases and the bO-gas fraction is carried out in a system of three or more reactors.

5. The method according to p. 1, characterized in that in the biforming process a reactor with a radial direction of the feed stream is used, mainly in the direction from the center to the periphery of the reactor

6. The method according to p. 1, characterized in that the process is carried out on a catalyst containing, wt.%: Acid component of at least 0.5; a metal component of at least 0.5; carrier rest up to 100.

7. The method according to p. 6, characterized in that as the acid component using aluminum hydroxychlorides of the formula AlOHCl ₂ .

8. The method according to p. 6, characterized in that as the acid component use surface tin oxychlorides of the formula SnOCl ₂ .

9. The method according to p. 6, characterized in that as the acid component of the catalyst using surface aluminum oxysulfates of the formula Al (OS0 ₄ ) ol ₅ -

10. The method according to p. 6, characterized in that as the acid component of the catalyst using surface oxysulfates from among metals titanium, zirconium, hafnium with the general formula MeOSO ₄ , where Me is Ti, Zr, Hf.

11. The method according to p. 6, characterized in that, as a metal component, the catalyst contains elements of VP, VIII groups in the ionic state in the oxidation state n> 0.

12. The method according to p. 6, characterized in that the metal component of the catalyst contains rhenium and platinum in the form of surface sulfides ReS _x and PtSy, where: x and y = 0.25-0.5.

13. The method according to p. 6, characterized in that the metal component of the catalyst contains platinum and palladium in the form of surface sulfides PtS _x and PdS _y , where: x and y = 0.25-0.5.

14. The method according to p. 6, characterized in that as a carrier, the catalyst contains alumina or a mixture of alumina with aluminosilicate clay.

15. The method according to p. 6, characterized in that the catalyst is prepared first by introducing into its composition an acid component, drying, calcining, and then metal components, followed by drying, calcination, reduction and sulphurization.