RU2388794C2 - Method of obtaining motor fuel constituents - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: method involves combined processing of C₁-C₄ - hydrocarbon gases and gasoline fractions with mass ratio C₁-C₄/C₅₊ not less than 3. The method also involves separation of liquid products of hydrogen-containing gas from C₅₊, extraction of liquid products of dissolved C₃-C₄ - hydrocarbon gases from C₅₊ and their re-circulation into the reaction zone of the process for secondary processing to C₅₊ - liquid hydrocarbons. After extraction of the said gases, a high-octane number component of motor fuel is obtained. The hydrogen-containing gas is split into hydrogen and C₁-C₄ - hydrocarbon gases by bonding hydrogen through a reaction of catalytic hydrogenation of aromatic hydrocarbons to cyclohexane hydrocarbons and re-circulating C₁-C₄ - hydrocarbon gases separated from hydrogen into the reaction zone of the process for secondary processing into C₅₊ - liquid hydrocarbons. Excess hydrogen extracted from cyclohexane hydrocarbons is taken to the step for combined processing of C₁-C₄ - hydrocarbon gases and gasoline fractions. C₃-C₄ - hydrocarbon gases from an external source are added for combined processing of C₁-C₄ - hydrocarbon gases and gasoline fractions. The process is carried out in two steps in the presence of a platinum-containing catalyst, where at the first step the catalyst is aged through treatment with C₅₊ hydrocarbons in amount of not less than 75 kg per 1 kg of catalyst at temperature not above 480°C, and at the second step, a mixture of gasoline fractions and C₁-C₄ - hydrocarbon gases is processed into C₅₊ high-octane number components of motor fuel at temperature above 460°C. The catalyst contains an acid component from: aluminium hydroxychloride of formula Al(OH)Cl₂. Surface tin oxychloride of formula SnOCl₂. Surface oxysulphates of metals - aluminium, titanium, zirconium, hafnium - of general formula MeOSO₄, where Me - Al, Ti, Zr, Hf and a metal component - platinum and rhernium or platinum and palladium in form of surface sulphides PtS_0.5, PdS_0.5, ReS_0.5, with the following content of components, in wt %: acid component not less than 0.5; metal component not less than 0.5; support (aluminium oxide or a mixture of aluminium oxide and aluminum silicate) the rest up to 100.

EFFECT: obtaining a high-octane number component of motor fuel with high output, low rate of reduction of aromatic hydrocarbon content of the product.

3 cl, 1 tbl, 2 dwg, 14 ex

Description

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. It can be used in the oil refining and gas processing industries.

Known methods for processing gasoline fractions of oil boiling at temperatures of 62-190 ° C, in high-octane components of motor fuels, aromatic hydrocarbons and hydrogen by catalytic reforming on catalysts containing platinum, chlorine and promoters on oxide supports (GPAntos, AMAitani, JMParera / Catalytic Naphtha Reforming. Science and Technology, Marcel Dekker Inc., 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 a method of producing high-octane components of motor fuels by reforming gasoline fractions with two-stage separation of reaction products (US 4615793, C10G 35/06, 1986). In the first stage of separation at elevated pressure and low temperature, a hydrogen-containing gas (Hash), 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 of separation at a higher temperature, hydrogen-rich and C ₂ -C ₅ hydrocarbon-rich gas is separated from the C ₅₊ liquid products, which is returned to the reaction zone for mixing with the feed. 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 the hydrocarbon gas from the second stage separator 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.

The closest to the achieved result to the proposed one is the method of production of high-octane components of motor fuels - BIFORMING-1 (RU 2144056, C10G 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 resulting mixture of gases (hydrogen and C ₁ -C ₄ hydrocarbon gases) is subjected to separation 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. C ₁ -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 C ₁ -C ₄ hydrocarbon gas is supplied to the recycle gas stream from an external source. The rate of hydrogen binding in the hydrogenation zone is maintained equal to the rate of hydrogen evolution in the biforming zone. Hydrogenation products are separated 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 ° C on a catalyst containing group VIII metal (s), cyclohexane series 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. Hydrocarbon gases dissolved in liquid high-octane C ₃ -C ₄ products are isolated in a distillation column and returned to the bioforming reaction zone for mixing with the feed (gasoline fraction). Hydrocarbon gases dissolved in liquid cyclohexane hydrocarbons C ₁ -C ₄ are separated by distillation and continuously recycled to mix with the liquid feed of the BIFORMING-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 reforming 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 consists in increasing 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 yield 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, while hydrocarbon gases are introduced along with the liquid feed (gasoline) C ₁ -C ₄ into the reaction zone. The components of light hydrocarbon gases, co-adsorbing on the surface of the “fresh” catalyst, form strongly adsorbed hydrocarbon fragments, which 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 carrying out the process in the presence of a catalyst containing an acid component from among - aluminum hydroxychloride of the formula Al (OH) Cl ₂ ; tin surface oxychloride of the formula SnOCl ₂ ; surface metal oxysulfates - aluminum, titanium, zirconium, hafnium - of the general formula MeOSO ₄ , where Me is Al, Ti, Zr, Hf, and the metal component is platinum and rhenium or platinum and palladium in the form of surface sulfides PtS _0.5 , PdS _{0 5} , ReS _0.5 , with the following content of components, wt.%:

acid component, not less 0.5 metal component, not less 0.5 carrier the rest is up to 100

moreover, 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 480 ° C, and in the second stage, the mixture of gasoline fractions and C is processed ₁ -C ₄ hydrocarbon gases in C ₅₊ are high-octane components of motor fuels at a temperature of more than 460 ° C and with constant supply of water and an organochlorine compound to the reaction zone to maintain the moisture content of a hydrogen-containing gas in the range of 10-25 ppm and molar s water / hydrogen chloride ratios between 15-25.

As a carrier, the catalyst contains alumina or a mixture of alumina with aluminosilicate 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 form dehydrogenated intermediates of extremely reactive carbon ions [Satterfield CN Heterogeneous Catalysis in Practice. McGraw-Hill, Inc., 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 best technical result in the proposed method for the production of motor fuels is provided when the process is carried out in two stages.

In the first stage, the catalyst is subjected to “aging” (running in) under typical conditions of catalytic reforming of gasoline fractions in an amount of not less than 75 kg of fraction per 1 kg of catalyst with the production of reformate with an octane according to the research method (IOI) of not more than 92 p. The surface of the catalyst is the formation of hydrocarbon fragments, which act as intermediate intermediates of the aromatization reactions of the 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 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 excludes the possibility of strong dissociative adsorption of light hydrocarbon gases, which on the surface of the "fresh" (unprocessed) catalyst is the cause of deactivation and a decrease in the efficiency of the process.

In the second stage of the process, a mixture of gasoline fractions is subjected to boiling range of 62-190 ° C and C ₁ -C ₄ hydrocarbon gases with a mass ratio of C ₁ -C ₄ / C _{5+ of} at least 0.03 in C ₅₊ high-octane components of motor fuels . This achieves the technical result of the proposed method, which is manifested in increasing the stability of the catalyst and increasing the yield of high-octane gasolines. The process in the second stage is carried out at a temperature of more than 460 ° C.

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 so that the moisture content of the WASH is in the range of 10 to 25 ppm and the molar ratio water / hydrogen chloride (H ₂ O / HCl) in the range of 15-25.

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 catalyst surface (coke precursors). One of the main conditions for good process stability is to ensure equality in the rates of formation and hydrogenation of coke precursors on the catalyst [V. Duplyakin, A. Belyi, N. Ostrovskii. New reforming catalysts of high resistance to deactivation // New Challendgers in Catalysis. Serbian Academy of Sciences and 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 is understood the kinetic laws of activation and diffusion (spillover) of 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 acid component of the 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 the molar ratio of H ₂ O / HCl is from 15 to 25. Under these conditions, the optimum hydrogen diffusion rates are achieved by surface 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.

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 conversion 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 of 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 forms of metals with an oxidation state of n> 1 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 prerequisite for realizing the effects of strong metal-carrier interaction is the use of elevated (at least 80 ° 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 is greater than zero) is determined by the adsorption method described in [Belyi AS, Kiryanov DI, Smolikov MD et. al. O ₂ -adsorption and (O ₂ -H ₂ ) -titration on electron deficient platinum in reforming catalysts. React Kinet. Catal. Lett., 1994, V. 53, No. 1, p. 183; Belyi AS New notion of active surface composition of reforming catalysts. React Linet. Catal. Lett., 1996, V. 57, No. 2, p. 344].

The invention is illustrated by the following examples.

Example 1. Illustrates a known method for the joint processing of C ₁ -C ₄ hydrocarbon gases and gasoline fractions into high-octane components of motor fuels.

The process is carried out on the installation, a flow chart of which is shown in figure 1, where

1 - reactor for the joint processing of C ₁ -C ₄ gases and gasoline fractions;

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

3 - a hydrogenation reactor for binding H ₂ and separating it from C ₁ -C ₄ ;

4 - methylcyclohexane dehydrogenation reactor to hydrogen and toluene;

5 - node separation of C ₁ -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).

In the process, a reactor 1 is used with a reaction zone volume of 100 cm ³ . A polymetallic 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 reactors 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 ° С (100 wt.%) With a density of 0.743 g / ml, which are mixed with a hydrogen-containing gas and fed into the reaction zone of the process at a temperature 495 ° C and a pressure of 2.2 MPa at a rate of 150 ml / h. The reaction products from the reactor 1 are cooled and fed to a separator 2, where the separation of unstable catalysis and a hydrogen-containing gas occurs.

Then, liquid C ₅₊ hydrocarbons (unstable catalysis) 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 entrance to the reaction zone.

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 ° 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 reaction zone for mixing with a continuously supplied gasoline fraction of 105-185 ° C.

Methylcyclohexane containing chemically bound hydrogen is subjected to dehydrogenation in reactor 4 at a temperature of 500 ° 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, and can also partially be recycled to the inlet of reactor 1. 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.

Thus, the basic principle of the process is implemented, which consists in the fact that hydrocarbon C ₁ -C ₄ gases formed in the process are not completely removed from the process as low-value side products, but are intensively recycled to the reaction zone, where they enter into joint transformations with high molecular weight components gasoline with the formation of high-octane components of motor fuels. At the same time, the main technical result of the 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.

Figure 2 shows data on the change in the content of octane-aromatic hydrocarbons during the process for 150 hours, where

1) a known method - example 1;

2) the proposed - example 2;

3) for comparison - example 3.

From the data presented in figure 2, it follows that when a mixture of hydrocarbon gases and gasoline is fed to the reactor on a fresh catalyst (curve 1) at a temperature of 495 ° C, a rather rapid dynamics of a decrease in catalyst activity is observed. The content 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 catalyst surface leads to intensive catalyst deactivation. The average rate of decrease in the content of aromatic hydrocarbons (W) is 9.3 (wt.% / Hour) × 10 ^-2 .

The specified disadvantage is eliminated by the proposed method.

Example 2. Illustrates the proposed method for the production of high-octane components of motor fuels, a catalyst and a method for its preparation. The process uses a catalyst of the following composition, wt.%:

acid component (ZrOSO ₄ ) 0.65 metal component 0.60 including: platinum ion 0.24 platinum metal 0.06 rhenium 0.30 carrier (alumina) up to 100

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 / AlOOH is 0.02 (calculated on calcined alumina). The mixture is dried with stirring to a moisture content of 58 wt.%, Molded into extrudates 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 .

The acidic carrier is evacuated to a residual pressure of 0.01 MPa and moistened with water (80 ml of water per 100 g of carrier), then 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 is} treated 0.6 g of hydrochloric acid. The carrier is treated for 1 hour at a temperature of 30 ° C, and then 1 hour at 80 ° 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 ° C to a moisture content of 12 wt.%, Calcined to a moisture content of 2.0 wt.%, Reduced with hydrogen at 500 ° 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 reactors 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 (fill the system once with hydrogen to a pressure of 1.0 MPa) at a temperature of 400 ° C. Under these conditions, aromatization reactions of naphthenic hydrocarbons begin to occur. The resulting hydrogen and hydrocarbon gases are removed from the process. The temperature is gradually raised to 460 ° C (in 6 hours), and then to 480 ° C in 10-12 hours. This temperature regime promotes the formation of hydrocarbon fragments on the surface, which act as intermediates in the formation of isoparaffin and aromatic hydrocarbons. The aging process of the active surface proceeds slowly, and to complete it requires at least 24-36 hours, which is equivalent to processing at least 75 kg of raw material per 1 kg of catalyst. The criterion for the completion of the aging process of the catalyst is the stabilization of the parameters of 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 IOC of not more than 92 p., Which is achieved when the content of aromatic hydrocarbons is up to 63 wt.% At a temperature of not more than 485 ° C. Then they proceed to the second stage of the process, organizing the recirculation of C ₁ -C ₄ hydrocarbon gases from the separator 5 and C ₃ -C ₄ liquefied gases from the separator 6 (Fig. 1) to the reaction zone to 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 facilitate their conversion under conditions of joint conversion with gasoline into high-octane components of motor fuels. Under these conditions (curve 2, figure 2), 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. The rate of decrease in the content of aromatic hydrocarbons is 1.9 (wt.% / Hour) × 10 ^-2 , which is 5 times less than in example 1. The stable operation of the catalyst is also ensured by the fact that water is continuously pumped into the feed stream at the inlet of reactor 1 and an organochlorine compound from among dichloroethane, trichlorethylene, carbon tetrachloride. The water feed rate is maintained such that the moisture content of the WASH from separator 2 is 10-25 ppm, and the molar ratio of H ₂ O / HCl 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 reaction cycle. If there is no supply of water and chlorine to the reaction zone, as well as when the moisture content of the WASH is more than 25 ppm, the efficiency of the process is reduced. The main parameters and results of the proposed method are shown in the table.

The average yield of the high-octane component (FOC) with IOC = 99.3 p. Under optimal conditions is 95 wt.% Calculated on the gasoline fraction, which indicates the achievement of the objectives of the present invention.

Example 3. Similar to example 2, but the acid component TiOSO ₄ in an amount of 0.6 wt.% Is introduced into the catalyst by mixing a solution of a salt of titanyl sulfate in acetic acid with aluminum hydroxide.

The true density of the product is 3.17 g / cm ³ .

The rate of decrease in the content of aromatic hydrocarbons is 1.7 (wt.% / Hour) × 10 ^-2 , which is 5.5 times less than in example 1.

The average yield of EQA with IOC = 99 p. Under optimal conditions is 94 wt.% Calculated on the gasoline fraction, which indicates the achievement of the objectives of the invention.

Example 4. Similar to example 2. As an acid component, HfOSO _{4 is used} in an amount of 0.65 wt.%, Which is introduced into the catalyst by mixing a solution of hafnium sulfate salt in acetic acid with aluminum hydroxide (modification of pseudoboehmite).

The true density of the product is 3.16 g / cm ³ .

The rate of decrease in the content of aromatic hydrocarbons is 2.1 (wt.% / Hour) × 10 ^-2 , which is 4.4 times less than in example 1. The main parameters and results of the proposed method are shown in the table.

The average yield of EQA with IOC = 98.8 p. Under optimal conditions is 95 wt.% Calculated on the gasoline fraction, which indicates the achievement of the objectives of the present invention.

Example 5. Illustrates the influence of the conditions of the aging stage of a fresh catalyst.

The aging (running-in) method is carried out in the same way as in example 2, with the difference that the aging time is reduced from 50 hours to 25 hours (from 75 kg to 37.5 kg of raw material per 1 kg of catalyst), and in the final stage of aging the conditions provided a more stringent mode in comparison with example 2. At a temperature in the reactor 1 equal to 485 ° C, the ROS of the catalysis is 98 p. with an aromatic hydrocarbon content of 69.5 wt. Data on the results of the process are shown in the table, from which it follows that under the running-in conditions of example 5, the efficiency of the process in the second stage decreases (compared with example 2). The rate of decrease in the content of aromatic hydrocarbons is 6.5 (wt.% / Hour) × 10 ^-2 , which is 3.4 times higher than this figure in example 2. Therefore, the more optimal conditions for aging of the catalyst is the mode with the production of EQA with IOC no more 92 p. In an amount of not less than 75 kg per 1 kg of catalyst.

Example 6. Illustrates the effect 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 reactor 1 (figure 1) at a temperature of 460 ° C. In this case, the ROS of catalysis is 91 p. With an aromatic hydrocarbon content of 58 wt.%. Therefore, the aim of the invention is achieved by carrying out the process at reaction temperatures of more than 460 ° C.

Example 7. The method is carried out as in example 2 with the difference that water is supplied to the reaction zone in an amount of 20 ppm, and chlorine in an amount of 0.5 ppm based on the feed. The humidity of the WASH is 30 ppm, and the ratio of H ₂ O / Cl is more than 40. From the table it follows that when the process is carried out in conditions of high humidity (more than 25 ppm) and when the amount of chlorine supplied to the system is insufficient, the efficiency of the process decreases. The wok output compared with example 2 is reduced from 95.0 to 92.8 wt.%, And IOC from 99.3 to 97 p. The decontamination rate increases from 1.9 to 2.9 (wt.% / Hour) × 10 ^-2 .

Example 8. Illustrates a decrease in the efficiency of the process by reducing the amount of C ₁ -C ₄ hydrocarbon gas supplied to the processing, from 3.0 to 1.5 wt.%.

Processing a mixture of C ₁ -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 is reduced from 3.0 to 1.5 wt.% With respect to the gasoline fraction. At the same time, the yield of the wok decreases from 95.0 to 91.5 wt.%, And the IOC from 99.3 to 96.5 p.

Example 9. 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.%.

The process uses a catalyst of the following composition, wt.%:

acid component (ZrOSO ₄ ) 0.60 Pt ⁺ metal component 0.30 carrier (alumina) the rest is up to 100

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 20 wt.%, Calcined to a moisture content of 1.0 wt.%. 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 and 1.0 g of hydrochloric acid. The carrier is treated with the solution with stirring for 1 h at a temperature of 30 ° C, and then 1 h at 80 ° 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 wt.%, Calcined to a moisture content of 2.0 wt.%, Reduced with hydrogen at 500 ° C, and sulphurization 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 woks from 95.0 to 92.5 wt.% And IOC from 99.3 to 95, 0 p.

Example 10. Illustrates the proposed method using a catalyst of the following chemical composition, wt.%:

acid component AlOHCl ₂ 7.0 metal component 0.6 including Pt ⁺ 0.3 Pd ⁺ 0.3 carrier (alumina) the rest is up to 100

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 aluminum oxide 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 ° C to a residual moisture content of 2.0 wt.%. The product contains 7.0 wt.% Chlorine and meets the formula Al ₁₉ O ₂₃ AlOHCl ₂ .

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, 0.3 g of palladium in the form of palladium chloride and 0.8 g of hydrochloric acid. The carrier is treated for 1 hour at a temperature of 25 ° C, and then 1 hour at 80 ° C. The solution is drained, the catalyst is dried, calcined, reduced with hydrogen at 500 ° C and sulfurized with hydrogen sulfide at the rate of S / Pt = 0.5 (mol).

The 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 of 25 ppm and dichloroethane to maintain the water / hydrogen chloride molar ratio of 25.

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

Example 11. In the process using a catalyst of the following composition, wt.%:

acid component of SnOCl ₂ 1,1 metal component 0.6 including Pt ⁺ 0.3 Pd ⁺ 0.3 carrier (alumina) the rest is up to 100

The acid component is introduced into the composition of the catalyst in a known manner (SU 1210284, B01J 23/62, 04/23/1984). 27 g of aluminum metal are dissolved in 110 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, molded at a moisture content of 60 wt.% Into extrudates, dried and calcined at 630 ° 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 . Further, as in example 2.

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

Water is continuously fed into the reactor to maintain a Wash moisture level of 10 ppm and trichlorethylene to maintain a water / hydrogen chloride molar ratio of 15.

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

Example 12. In the process using a catalyst of the following composition, wt.%:

acid component AlOSO ₄ 4.3 metal component 0.6 including Pt ⁺ 0.3 Re 0.3 carrier the rest is up to 100 of which: aluminum oxide 80 aluminosilicate clay (montmorillonite) twenty

Aluminum oxysulfate is prepared in a known manner (RU 2050187, B01J 23/656, 12.20.1995).

Aluminum hydroxide (80 g per alumina) is mixed with 20 g montmorillonite (in terms of calcined aluminosilicate) and sulfuric acid (3.0 g) at 20 ° C with the addition of 8.2 ml of acetic acid. The mass is formed into granules, dried and calcined at 580 C. Under these conditions, an oxysulfate of the composition Al ₁₉ O ₂₇ (AlOSO ₄ ) _0.32 with a sulfate ion content of 3.0 wt.% Is formed. Further, as in example 2.

The process is carried out under the conditions given in the table. The process provides an EQA with an IOC of 103 p. With a yield of 98.8 wt.%.

Example 13. The process is carried out as in example 12, but with the difference that it proceeds in a system of three reactors.

The formation of high-octane components of motor fuels, including aromatic hydrocarbons, under the process proceeds with 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 process. Using the same amount of catalyst 100 cm ³ , but with 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 14. The process is carried out as in example 13, 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 (see table). This is manifested in the achievement of high performance at even lower temperatures.

Claims (3)

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, comprising in a reactor system:
joint processing of C ₁ -C ₄ hydrocarbon gases and gasoline fractions with a mass ratio of C ₁ -C ₄ / C _{5+ of} at least 3,
then separation from C ₅₊ liquid products of hydrogen-containing gas,
then the allocation of C ₅₊ liquid products of dissolved C ₃ -C ₄ hydrocarbon gases and their recirculation to the reaction zone of the process for recycling into
With ₅₊ liquid products, in this case, after the emission of the above gases, a high-octane component of motor fuels is obtained,
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 recirculation of C ₁ -C ₄ hydrocarbon gases separated from hydrogen into the reaction zone of the process for secondary processing into C ₅₊ - liquid hydrocarbons,
introduction to the stage of joint processing of C ₁ -C ₄ hydrocarbon gases and gasoline fractions of excess hydrogen extracted from hydrocarbons of the cyclohexane series and, possibly, excess hydrogen mixed with C ₁ -C ₄ hydrocarbon gases obtained at the stage of separation of the hydrogen-containing gas,
adding to the joint processing of C ₁ -C ₄ hydrocarbon gases and gasoline fractions of C ₃ -C ₄ hydrocarbon gases from an external source, characterized in that the process is carried out on a catalyst containing: an acid component - aluminum hydroxychloride of the formula Al (OH) Cl ₂ ; tin surface oxychloride of the formula SnOCl ₂ ; surface metal oxysulfates - aluminum, titanium, zirconium, hafnium - of the general formula MeOSO ₄ , where Me is Al, Ti, Zr, Hf, the metal component is platinum and rhenium or platinum and palladium in the form of surface sulfides PtS _0.5 , PdS _{0, 5} , ReS _0.5 , and the carrier is alumina or a mixture of alumina with aluminosilicate in the following components, wt.%:
acid component not less than 0.5 metal component not less than 0.5 carrier the rest is up to 100
moreover, 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 480 ° C, and in the second stage, the mixture of gasoline fractions and C is processed C ₁ -C ₄ hydrocarbyl gases in the C ₅₊ - high octane motor fuel components at a temperature above 460 ° C and at a constant water feed to the reaction zone and organochlorine compounds to maintain hydrogen-containing gas humidity in the range of 10-25 million ^-1 and molnog about the ratio of water / hydrogen chloride in the range of 15-25. 2. The method according to claim 1, characterized in that the catalyst is prepared first by introducing into its composition an acid component, drying, calcining, and then a metal component, followed by drying, calcination, reduction and sulphurization. 3. The method according to claim 1, characterized in that the reactor is used with a radial flow direction, mainly from the center of the reactor to the periphery.

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