RU2620267C1 - Catalyst for vacuum gas oil hydrotreating and method of preparation thereof - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: catalyst comprises the following in wt %: cobalt oxide 5.0-9.0, tungsten oxide 7.0-14.0, molybdenum oxide 7.0-14.0, aluminium oxide in the form of mixture consisting of 30-50 wt % of aluminium axide in the form of boehmite and 50-70 wt % of aluminium oxide obtained by pretreatment of aluminium hydroxide with 4-7% nitric acid solution at a solution temperature of 5-10°C and spray-dried in hot air flow at a temperature of 150-210°C - the rest. Method of catalyst preparation consists in that the carrier is prepared by mixing 30-50 wt % of auminum oxide in the form of boehmite and 50-70 wt % of aluminium oxide obtained by pretreatment of aluminium hydroxide with 4-7% nitric acid solution at a solution temperature of 5-10°C and spray-dried in hot air flow at a temperature of 150-210°C. The resulting mixture is moistened, 7.5% solution of nitric acid is added, stirred until a homogeneous mass is obtained and ammonium heptamolybdate solution is added. Triethylene glycol is added, stirred until a homogeneous mass is obtained, granules are formed by extrusion, dried and calcined. The calcined carrier is impregnated with a combined solution of silicotungstic acid and cobalt nitrate at a weight ratio H₈[Si (W₂O₇)₆]×H₂O: Co (NO₃)2=1:1.12-1:4.04, dried and calcined.

EFFECT: increased catalytic activity, high mechanical strength and porous structure.

2 cl, 1 tbl, 5 ex

Description

The invention relates to catalytic chemistry, in particular to catalysts for hydrofining vacuum gas oils, and can be used in the oil refining industry.

A steady increase in the depth of oil refining due to the development of thermo-destructive and thermocatalytic processes allows to increase the production of light oil products and at the same time requires even greater development of hydrocatalytic processes.

Vacuum gas oils are the raw material for catalytic cracking, hydrocracking, and electrode coke processes. In order to increase the yield and improve the quality of the products obtained in these processes, as well as to reduce environmental pollution by sulfur and nitrogen oxides, an increasing proportion of vacuum gas oils produced is subjected to hydrofining.

Due to the hydrofinishing process of vacuum gas oil, the following decreases: the content of sulfur compounds in the feedstock, which can significantly reduce emissions of sulfur oxides from a catalytic cracking unit and the sulfur content in cracking products; the content of nitrogen compounds and polyaromatic hydrocarbons, which leads to a decrease in the negative effect of basic nitrogen on the acid sites of the cracking catalyst, a decrease in coke deposition, and, as a result, an increase in the activity and selectivity of the catalyst; metal content in raw materials and its coking properties, which significantly reduces catalyst consumption.

Hydrotreated vacuum gas oil is a valuable raw material for catalytic cracking units, since its processing leads to an increase in the yield of cracked gasoline, an increase in its octane number and a decrease in sulfur content.

Therefore, the creation of catalysts with high activity in the reactions of gas oil removal of sulfur compounds, nitrogen-containing compounds and heavy metals from high molecular weight raw materials - vacuum gas oils, is a very important task.

The catalyst for hydrofining vacuum gas oils, in addition to the high catalytic activity in the reactions of hydrodesulfurization and hydrodeazotization, must have a developed porous structure and high mechanical strength.

Various catalysts for hydrofining oil fractions and methods for their preparation are known, but a common disadvantage for them is the high residual sulfur content in the resulting products.

A known catalyst for hydrotreating oil fractions and a method for its preparation. The catalyst contains, wt.%: 14.3-27.5 P [(MoO ₃ ) ₁₂ ], 3.2-8.5 CoO, 0.9-7.5 borophosphate, 56.5-81.6 Al ₂ O ₃ . As a carrier for this catalyst, a mixture of alumina and borophosphate of variable composition formed at the stage of synthesis from H ₃ BO ₃ and H ₃ PO _{4 is used} . A catalyst preparation method involves impregnating a support with a joint impregnating solution of Group VIII and VI metal compounds containing a molybdenum heteropoly compound, cobalt nitrate and a solution stabilizer — an organic dibasic acid selected from citric, tartaric, or ascorbic acids, at a pH of 1.5–5.0 s subsequent heat treatment. RU 2497586 C2, 11/10/2013.

The disadvantage of this catalyst is its multicomponent composition, as well as low activity in the reactions of hydrodesulfurization of diesel fractions (the residual sulfur content in the hydrogenate is 39-50 ppm).

A known catalyst for hydrofining oil fractions and a method for its preparation. The catalyst contains, wt.%: CoO (NiO) - 4.0-8.0, MoO ₃ - 14.0-21.0, P ₂ O ₅ - 2.0-6.0, Al ₂ O ₃ - the rest . The catalyst is prepared as follows: in the first stage, a support is obtained by peptization of aluminum hydroxide with a mixture of nitric and phosphoric acids taken in a ratio of 1: 0.2-1: 0.5 mass fractions, formed as extrudates, dried at a temperature of 100-120 ° C for 3-5 hours at a rate of temperature rise of 20-30 ° C / h and calcined at a temperature of 400-700 ° C for 4 hours, then the carrier is impregnated in two stages with intermediate drying at a temperature of 100-120 ° C for 4 hours at a rate of temperature rise of 20-25 ° C / h, provided that the solution of the molybdenum salt is olzuemy the first impregnation step has a pH of 3-6. RU 2074769 C1, 03/10/1997.

The disadvantage of the proposed catalyst is the low degree of hydrodesulfurization of vacuum gas oil (residual sulfur content is 1000 ppm). The disadvantage of the catalyst preparation method is the high calcination temperature (700 ° C), which negatively affects both the structural and acidic properties of alumina, which is a component of the catalyst.

A known catalyst for the hydrodesulfurization of straight-run gas oil based on aluminum oxide, which contains, in terms of oxide content, wt.%: CoO - 2-10, MoO ₃ - 10-30, P ₂ O ₅ - 4-10, Al ₂ O ₃ - the rest . The catalyst is obtained by impregnating a calcined alumina-based support with a joint solution of cobalt, molybdenum and phosphoric acid salts, followed by drying and calcination in moist air at a temperature of 250-600 ° C. RU 2192923 C2, 11.20.2002.

The disadvantage of this catalyst is the complexity of the technological design stage of calcination in moist air, as well as the difficulties of applying a large amount of molybdenum oxide - 30 wt.% By impregnation.

The closest in its technical essence and the achieved technical result to the proposed invention is a catalyst for hydrotreating oil fractions and a method for its preparation. The catalyst contains, wt.%: CoO (NiO) - 3-5, MoO ₃ - 10-14, silicon-tungsten complex - 1.02-4.08, Al ₂ O ₃ - the rest. A method of producing a catalyst includes preparing a carrier followed by impregnation thereof. At the first stage, the production of an aluminum-molybdenum carrier is carried out: for this, a solution of ammonium molybdenum acid is introduced into aluminum hydroxide peptized with monobasic acid, stirred, evaporated to a residual moisture content of 70 wt.%, Formed as extrudates, dried and calcined with a final calcination temperature of the carrier of 600 ° C. At the second stage, a single impregnation of the calcined extrudates is carried out with an impregnating solution containing silicotungsten acid and cobalt (nickel) nitrate Co (Ni) (NO ₃ ) ₂ ⋅ 6H ₂ O, followed by heat treatment of the finished catalyst at a temperature of no higher than 500 ° C. RU 2147255 C1, 10.04.2000.

The disadvantage of the prototype is the insufficiently high degree of desulfurization in the process of hydrotreating fractions of diesel fuel (94.6-96.5 rel.%).

The technical problem solved by the claimed group of inventions is to create an improved catalyst for the hydrofining of vacuum gas oil and a method for its preparation, characterized by increased activity in the hydrogenolysis of hetero compounds, especially sulfur-containing ones, by the simplicity and adaptability of a catalyst preparation method involving the single-stage introduction of active metal oxides into the catalyst composition.

The technical result from the implementation of the claimed group of inventions is to increase the catalytic activity in the hydrodesulfurization and deazotization reactions occurring during the hydrofining of vacuum gas oil through the use of a carrier with a high internal surface and a large pore volume, while achieving high mechanical strength and a porous structure, providing a total deposition by impregnation from 25 to 35 wt.% of the active components of the catalyst, and the degree of conversion of sulfur is not less than 97.3%, and for nitrogen not less than 80.3 rel.

The technical result from the implementation of the claimed group of inventions is achieved in that the catalyst contains tungsten oxide as a tungsten compound, and the alumina in the aluminum-molybdenum support contains in the form of a mixture consisting of 30-50 wt.% Alumina in the form of boehmite and 50-70 wt. % alumina obtained by pretreatment of aluminum hydroxide with a 4-7% solution of nitric acid at a solution temperature of 5-10 ° C and dried by spraying in a stream of hot air at a temperature of 150-210 ° C, while the ratio of ingredients dressed in the following limits, wt.%:

cobalt oxide 5.0-9.0 tungsten oxide 7.0-14.0 molybdenum oxide 7.0-14.0 aluminum oxide in the form of a mixture consisting, wt.%: from 30-50 alumina in the form of boehmite and 50-70 alumina, obtained by pretreatment of aluminum hydroxide 4-7% nitric acid solution at solution temperature 5-10 ° C and spray dried in a stream of hot air at a temperature of 150-210 ° C rest,

as well as the method of its preparation, according to which the carrier is prepared by mixing 30-50 wt.% alumina in the form of boehmite and 50-70 wt.% alumina obtained by pretreating aluminum hydroxide with a 4-7% nitric acid solution at a solution temperature of -10 ° C and dried by spraying in a stream of hot air at a temperature of 150-210 ° C, the mixture is moistened, a 7.5% solution of nitric acid is added, stirred until a homogeneous mass is added and a solution of ammonium molybdenum acid is added, triethylene glycol is added, mixed until obtained homogeneous mass, formed into granules by extrusion, dried and calcined, the calcined support is impregnated with a joint solution of silicotungsten acid and cobalt nitrate, taken in the mass ratio of H ₈ [Si (W ₂ O ₇ ) ₆ ] × H ₂ O: Co (NO ₃ ) ₂ = 1: 1.12-1: 4.04, dried and calcined

The resulting catalyst has a pore volume of 0.5-0.6 ml / g, a specific surface area of 150-200 m ² / g and an average pore diameter of 10-12 nm, a coefficient of strength of 2.0-3.0 kg / mm

The invention is illustrated by the following examples.

Example 1

An example illustrates a method for preparing an alumina-cobalt-tungsten catalyst based on an alumina-molybdenum granular support. To obtain the carrier, a mixture of aluminum hydroxide - boehmite (40 wt.%) And aluminum hydroxide powder (60 wt.%), Treated with a 5% solution of nitric acid and a solution of ammonium salt of molybdenum acid, consisting of 10.23 g of ammonium molybdenum acid and 27 are used. , 31 ml of distilled water.

Sample catalyst composition, wt.%: Cobalt oxide (CoO) - 5.0, tungsten oxide (WO ₃ ) - 14.0, molybdenum oxide (MoO ₃ ) - 7.0, aluminum oxide (Al ₂ O ₃ ) - the rest cook in the following way.

Preliminarily, 68.35 g of aluminum hydroxide is treated with 51.26 ml of a 5% solution of nitric acid at a solution temperature of 5 ° C and dried for 6 hours by spraying in a stream of hot air at a temperature of 150 ° C.

47.96 g of boehmite and 68.35 g of aluminum hydroxide treated with a 5% solution of nitric acid are mixed and moistened with 104.67 ml of distilled water. Then a peptizing 7.5% nitric acid solution is added, containing 3.61 ml of nitric acid (65%) and 60.57 ml of distilled water, and mixed. To a homogeneous peptized mixture is added a solution of ammonium molybdenum salt, consisting of 10.23 g of ammonium molybdenum and 27.31 ml of distilled water. After thoroughly mixing the mass, add 5.82 ml of pore-forming agent - triethylene glycol and mix until smooth. The resulting mass is extruded through a 1.5 mm diameter die. The extrudates are held in air for 6 hours and placed in a muffle furnace. The drying mode is stepwise: 60 ° C for 2 hours, 80 ° C for 2 hours, 100 ° C for 2 hours, 120 ° C for 2 hours, 140 ° C for 4 hours, 160 ° C for 2 hours. at a rate of 2 ° C / min to a temperature of 550 ° C. At a temperature of 550 ° C incubated for 4 hours

25.86 g of cobalt nitrate is dissolved in 14.48 ml of distilled water and mixed with a solution consisting of 23.01 g of silicotungsten acid and 12.89 ml of distilled water. The volume of the impregnating solution is adjusted to 76.98 ml (the pH of the solution is 7.0) and added to 85.53 g of a calcined carrier. The mass ratio of components in the impregnating solution is H ₈ [Si (W ₂ O ₇ ) ₆ ] * H ₂ O: Co (NO ₃ ) ₂ = 1: 1.12. The carrier is impregnated for 20 minutes with stirring, after which the excess solution is decanted. Then the catalyst sample is placed in a muffle furnace, dried stepwise: 60 ° C - 2 hours, 80 ° C - 2 hours, 100 ° C - 2 hours, 120 ° C - 2 hours, 140 ° C - 4 hours, 160 ° C - 2 hours, after which the catalyst is calcined at a temperature of 500 ° C for 4 hours

Example 2

An example illustrates a method for preparing an alumina-cobalt-tungsten catalyst based on an alumina-molybdenum granular support. To obtain the carrier, a mixture of aluminum hydroxide - boehmite (40 wt.%) And aluminum hydroxide powder (60 wt.%), Treated with 5% nitric acid solution, a solution of ammonium molybdenum acid salt, consisting of 15.68 g of ammonium molybdenum acid and 41 88 ml of distilled water.

Sample catalyst composition, wt.%: Cobalt oxide (CoO) - 7.0, tungsten oxide (WO ₃ ) - 10.0, molybdenum oxide (MoO ₃ ) - 11.0, aluminum oxide (Al ₂ O ₃ ) - the rest cook in the following way.

Previously, 64.90 g of aluminum hydroxide is treated with 48.67 ml of a 5% solution of nitric acid at a solution temperature of 5 ° C and dried for 6 hours by spraying in a stream of hot air at a temperature of 190 ° C.

45.54 g of boehmite and 64.90 g of aluminum hydroxide treated with a 5% solution of nitric acid are mixed and moistened with 99.39 ml of distilled water. Then a peptizing 7.5% solution of nitric acid is added, containing 3.42 ml of nitric acid (65%) and 57.51 ml of distilled water, and mixed. To a homogeneous peptized mixture is added a solution of ammonium salt of molybdenum acid, consisting of 15.68 g of ammonium molybdenum acid and 41.88 ml of distilled water. After thoroughly mixing the mass, 5.52 ml of pore-forming agent, triethylene glycol, is added and mixed until homogeneous. The resulting mass is extruded through a 1.5 mm diameter die. The extrudates are held in air for 6 hours and placed in a muffle furnace. The drying mode is stepwise: 60 ° C for 2 hours, 80 ° C for 2 hours, 100 ° C for 2 hours, 120 ° C for 2 hours, 140 ° C for 4 hours, 160 ° C for 2 hours. at a rate of 2 ° C / min to a temperature of 550 ° C. At a temperature of 550 ° C incubated for 4 hours

36.21 g of cobalt nitrate are dissolved in 20.28 ml of distilled water and mixed with a solution consisting of 16.44 g of silicotungsten acid and 9.20 ml of distilled water. The volume of the impregnating solution is adjusted to 78.88 ml (the pH of the solution is 7.0) and added to 87.65 g of a calcined carrier. The mass ratio of components in the impregnating solution is H ₈ [Si (W ₂ O ₇ ) ₆ ] * H ₂ O: Co (NO ₃ ) ₂ = 1: 2.20. The carrier is impregnated for 20 minutes with stirring, after which the excess solution is decanted. Then the catalyst sample is placed in a muffle furnace, dried stepwise: 60 ° C - 2 hours, 80 ° C - 2 hours, 100 ° C - 2 hours, 120 ° C - 2 hours, 140 ° C - 4 hours, 160 ° C - 2 hours, after which the catalyst is calcined at a temperature of 500 ° C for 4 hours

Example 3

An example illustrates a method for preparing an alumina-cobalt-tungsten catalyst based on an alumina-molybdenum granular support. To obtain the carrier, a mixture of aluminum hydroxide - boehmite (40 wt.%) And aluminum hydroxide powder (60 wt.%) Treated with a 5% solution of nitric acid, a solution of ammonium salt of molybdenum acid, consisting of 19.72 g of ammonium molybdenum acid and 52 , 66 ml of distilled water.

Sample catalyst composition, wt.%: Cobalt oxide (CoO) - 9.0, tungsten oxide (WO ₃ ) - 7.0, molybdenum oxide (MoO ₃ ) - 14.0, aluminum oxide (Al ₂ O ₃ ) - the rest cook in the following way.

Previously, 62.34 g of aluminum hydroxide is treated with 46.76 ml of 5% nitric acid solution at a solution temperature of 7 ° C and dried for 6 hours by spraying in a stream of hot air at a temperature of 190 ° C.

43.74 g of boehmite and 62.34 g of aluminum hydroxide treated with a 5% solution of nitric acid are mixed and moistened with 96.46 ml of distilled water. Then a peptizing 7.5% nitric acid solution is added, containing 3.29 ml of nitric acid (65%) and 55.25 ml of distilled water, and mixed. To a homogeneous peptized mixture add a solution of ammonium salt of molybdenum, consisting of 19.72 g of ammonium molybdenum and 52.66 ml of distilled water. After thoroughly mixing the mass, 5.30 ml of pore-forming agent, triethylene glycol, is added and mixed until homogeneous. The resulting mass is extruded through a 1.5 mm diameter die. The extrudates are held in air for 6 hours and placed in a muffle furnace. The drying mode is stepwise: 60 ° C for 2 hours, 80 ° C for 2 hours, 100 ° C for 2 hours, 120 ° C for 2 hours, 140 ° C for 4 hours, 160 ° C for 2 hours. at a rate of 2 ° C / min to a temperature of 550 ° C. At a temperature of 550 ° C incubated for 4 hours

46.55 g of cobalt nitrate is dissolved in 26.07 ml of distilled water and mixed with a solution consisting of 11.51 g of silicotungsten acid and 6.44 ml of distilled water. The volume of the impregnating solution is adjusted to 79.83 ml (the pH of the solution is 7.0) and added to 88.70 g of a calcined carrier. The mass ratio of the components in the impregnating solution is H ₈ [Si (W ₂ O ₇ ) ₆ ] * H ₂ O: Co (NO ₃ ) ₂ = 1: 4.04. The carrier is impregnated for 20 minutes with stirring, after which the excess solution is decanted. Then the catalyst sample is placed in a muffle furnace, dried stepwise: 60 ° C - 2 hours, 80 ° C - 2 hours, 100 ° C - 2 hours, 120 ° C - 2 hours, 140 ° C - 4 hours, 160 ° C - 2 hours, after which the catalyst is calcined at a temperature of 500 ° C for 4 hours

Example 4

An example illustrates a method for preparing an alumina-cobalt-tungsten catalyst based on an alumina-molybdenum granular support. To obtain the carrier using a mixture of aluminum hydroxide - boehmite (30 wt.%) And powder of aluminum hydroxide (70 wt.%), Treated with 4% nitric acid solution, a solution of ammonium salt of molybdenum acid, consisting of 15.68 g of ammonium molybdenum acid and 41 88 ml of distilled water.

Sample catalyst composition, wt.%: Cobalt oxide (CoO) - 7.0, tungsten oxide (WO ₃ ) - 10.0, molybdenum oxide (MoO ₃ ) - 11.0, aluminum oxide (Al ₂ O ₃ ) - the rest cook in the following way.

Preliminarily, 75.71 g of aluminum hydroxide is treated with 56.79 ml of a 4% solution of nitric acid at a solution temperature of 7 ° C and dried for 6 hours by spraying in a stream of hot air at a temperature of 200 ° C.

34.15 g of boehmite and 75.71 g of aluminum hydroxide treated with a 4% solution of nitric acid are mixed and moistened with 98.88 ml of distilled water. Then a peptizing 7.5% nitric acid solution is added, containing 3.41 ml of nitric acid (65%) and 57.22 ml of distilled water, and mixed. To a homogeneous peptized mixture is added a solution of ammonium salt of molybdenum acid, consisting of 15.68 g of ammonium molybdenum acid and 41.88 ml of distilled water. After thoroughly mixing the mass, add 5.49 ml of pore-forming agent - triethylene glycol and mix until smooth. The resulting mass is extruded through a 1.5 mm diameter die. The extrudates are held in air for 6 hours and placed in a muffle furnace. The drying mode is stepwise: 60 ° C for 2 hours, 80 ° C for 2 hours, 100 ° C for 2 hours, 120 ° C for 2 hours, 140 ° C for 4 hours, 160 ° C for 2 hours. at a rate of 2 ° C / min to a temperature of 550 ° C. At a temperature of 550 ° C incubated for 4 hours

36.21 g of cobalt nitrate are dissolved in 20.28 ml of distilled water and mixed with a solution consisting of 16.44 g of silicotungsten acid and 9.20 ml of distilled water. The volume of the impregnating solution is adjusted to 78.88 ml (the pH of the solution is 7.0) and added to 87.65 g of a calcined carrier. The mass ratio of the components in the impregnating solution is H ₈ [Si (W ₂ O ₇ ) × H ₂ O: Co (NO ₃ ) ₂ = 1: 2.20. The carrier is impregnated for 20 minutes with stirring, after which the excess solution is decanted. Then the catalyst sample is placed in a muffle furnace, dried stepwise: 60 ° C - 2 hours, 80 ° C - 2 hours, 100 ° C - 2 hours, 120 ° C - 2 hours, 140 ° C - 4 hours, 160 ° C - 2 hours, after which the catalyst is calcined at a temperature of 500 ° C for 4 hours

Example 5

The example illustrates a method for producing alumina-cobalt-tungsten catalyst based on alumina-molybdenum granular support. To obtain the carrier using a mixture of aluminum hydroxide - boehmite (50 wt.%) And powder of aluminum hydroxide (50 wt.%), Treated with a 7% solution of nitric acid, a solution of ammonium salt of molybdenum acid, consisting of 19.72 g of ammonium molybdenum acid and 52 , 66 ml of distilled water.

Sample catalyst composition, wt.%: Cobalt oxide (CoO) - 9.0, tungsten oxide (WO ₃ ) - 7.0, molybdenum oxide (MoO ₃ ) - 14.0, aluminum oxide (Al ₂ O ₃ ) - the rest cook in the following way.

Preliminarily, 56.68 g of aluminum hydroxide is treated with 42.51 ml of a 7% solution of nitric acid at a solution temperature of 10 ° C and dried for 6 hours by spraying in a stream of hot air at a temperature of 210 ° C.

59.65 g of boehmite and 56.68 g of aluminum hydroxide treated with a 7% solution of nitric acid are mixed and moistened with 104.70 ml of distilled water. Then a peptizing 7.5% nitric acid solution is added, containing 3.61 ml of nitric acid (65%) and 60.58 ml of distilled water, and mixed. To a homogeneous peptized mixture add a solution of ammonium salt of molybdenum, consisting of 19.72 g of ammonium molybdenum and 52.66 ml of distilled water. After thoroughly mixing the mass, add 5.82 ml of pore-forming agent - triethylene glycol and mix until smooth. The resulting mass is extruded through a 1.5 mm diameter die. The extrudates are held in air for 6 hours and placed in a muffle furnace. The drying mode is stepwise: 60 ° C for 2 hours, 80 ° C for 2 hours, 100 ° C for 2 hours, 120 ° C for 2 hours, 140 ° C for 4 hours, 160 ° C for 2 hours. at a rate of 2 ° C / min to a temperature of 550 ° C. At a temperature of 550 ° C, they stand for 4 hours.

46.55 g of cobalt nitrate is dissolved in 26.07 ml of distilled water and mixed with a solution consisting of 11.51 g of silicotungsten acid and 6.44 ml of distilled water. The volume of the impregnating solution is adjusted to 79.83 ml (the pH of the solution is 7.0) and added to 88.70 g of a calcined carrier. The mass ratio of the components in the impregnating solution is H ₈ [Si (W ₂ O ₇ ) ₆ ] * H ₂ O: Co (NO ₃ ) ₂ = 1: 4.04. The carrier is impregnated for 20 minutes with stirring, after which the excess solution is decanted. Then the catalyst sample is placed in a muffle furnace, dried stepwise: 60 ° C - 2 hours, 80 ° C - 2 hours, 100 ° C - 2 hours, 120 ° C - 2 hours, 140 ° C - 4 hours, 160 ° C - 2 hours, after which the catalyst is calcined at a temperature of 500 ° C for 4 hours

The efficiency of the catalyst was evaluated in the process of hydrofining a vacuum gas oil containing 2.06 wt.% Sulfur and 0.18 wt.% Nitrogen by passing hydrogen-containing gas and feed with a volume ratio of hydrogen to feed 600: 1 through a fixed catalyst layer loaded into a tubular reactor, with a bulk velocity of 0.5-1.0 h ^-1 at a temperature of 400 ° C under a pressure of 5.5 MPa in terms of the content of residual sulfur and nitrogen in a stable hydrogenate.

Before carrying out the hydrofining process, the catalyst is sulfidated with dimethyldisulfide in a stream of hydrogen at a temperature of 300 ° C.

The performance of the hydrofinishing process of vacuum gas oil, carried out using samples of the catalysts corresponding to the invention, are presented in the table.

From the table it follows that the inventive catalyst for hydrofining the raw fractions of vacuum gas oil, prepared by the claimed method, provides a hydrotreated vacuum gas oil with a degree of desulfurization of at least 97.3 rel.% And a degree of dezotization of at least 80.3 rel.%.

Claims (3)

1. The catalyst for hydrofinishing of a vacuum gas oil containing cobalt oxide, a tungsten compound and a carrier consisting of aluminum oxide and molybdenum oxide, characterized in that it contains tungsten oxide as a tungsten compound, and contains aluminum oxide in an aluminum-molybdenum carrier in the form of a mixture consisting of 30-50 wt.% Alumina in the form of boehmite and 50-70 wt.% Alumina obtained by pretreatment of aluminum hydroxide with a 4-7% solution of nitric acid at a solution temperature of 5-10 ° C and a dried spray lowering in a stream of hot air at a temperature of 150-210 ° C, while the ratio of ingredients is in the following ranges, wt.%: cobalt oxide 5.0-9.0 tungsten oxide 7.0-14.0 molybdenum oxide 7.0-14.0 aluminum oxide in the form of a mixture consisting, wt.%: from 30-50 alumina in the form of boehmite 50-70 alumina, obtained by pretreatment of aluminum hydroxide 4-7% nitric acid solution at solution temperature 5-10 ° C and spray dried in a stream of hot air at a temperature of 150-210 ° C rest 2. A method of preparing a catalyst for hydrofinishing a vacuum gas oil, characterized according to claim 1, comprising obtaining a carrier by mixing 30-50 wt.% Alumina in the form of boehmite and 50-70 wt.% Alumina obtained by pretreatment of aluminum hydroxide 4-7% - with a solution of nitric acid at a solution temperature of 5-10 ° C and dried by spraying in a stream of hot air at a temperature of 150-210 ° C, the mixture is moistened, a 7.5% solution of nitric acid is added, mixed until a homogeneous mass is obtained and an ammonium solution is introduced molyb enovokislogo added triethylene glycol, stirred until a homogeneous mass is formed granules by extrusion, dried and calcined, the calcined support is impregnated with co-solution of silicotungstic acid and cobalt nitrate in a weight ratio of H ₈ [Si (W ₂ O _{7) 6]} xH ₂ O: Co (NO ₃ ) ₂ = 1: 1.12-1: 4.04, dried and calcined.