RU2183503C2 - Catalyst and method for cracking of heavy petroleum fractions - Google Patents

Abstract

FIELD: petroleum processing. SUBSTANCE: catalyst contains 30-60% high-silica zeolite, 15-40% hydrogenation components, 1-4% fillers, and binding component - the rest. Process involving such catalyst is carried out at 340 to 450 C, pressure 0.1 to 10 MPa and volumetric flow rate for raw material 1 to 3 R^-1. EFFECT: increased yield of light petroleum products. 4 cl, 2 tbl, 18 ex

Description

 The invention relates to the field of oil refining, in particular to catalytic cracking processes of heavy oil fractions.

 Cracking of heavy fractions of oil (vacuum gas oil, fuel oil, tar or mixtures thereof), in order to obtain gasoline and diesel fuel, is currently mainly carried out on microspherical catalysts.

 A known catalyst for cracking residual petroleum feedstock containing zeolite, a binder component, hydrogenating components and fillers, and also known is a method of cracking said feedstock using this catalyst (Thematic Review. "Catalysts for Cracking Residual Petroleum Feed", TsNIITEneftekhim, M, 1991, p. 39 ) (prototype).

 However, this catalyst has a low activity.

The technology for the preparation of catalysts is characterized by multistage and complexity in connection with obtaining microspheres. There are several options for producing cracking catalysts, which include the following stages: synthesis of zeolite U, activation of the zeolite by cation exchange for H ⁺ or REE ⁺⁺⁺ to deeply displace sodium from the zeolite, mixing the catalyst components to obtain a gel or sol, washing the catalytic system with water and the purpose of removing excess sodium, spray drying the gel or sol in order to obtain a microsphere, calcination of the microsphere. Existing processes for the production of cracking catalysts are characterized by the formation of a large volume of wastewater (Thematic review "Catalysts for cracking of residual crude oil", TsNIITEneftekhim, M., 1991, p. 28, 29) (prototype).

Catalytic cracking processes are carried out on existing catalysts in a fluidized bed at temperatures above 500 ^o C, the processes are complex and energy-intensive (A.I. Samokhvalov. "Experience in the development and operation of a combined catalytic cracking unit G-43-107", Chemistry and technology of fuels and oils , 3, 1998, p. 15). At temperatures below 500 ^o With the existing catalysts do not work.

 The aim of the present invention is to increase the activity of the catalysts, simplifying the technology of their preparation and technology for the implementation of cracking processes of heavy oil residues.

 This goal is achieved by using the catalyst of the proposed composition, the technology of its preparation and the technological parameters of the process on the developed catalyst.

The composition of the proposed catalyst
1. High-silica zeolite, including in cationically substituted form, with a silicate module of 12-150 with a sodium oxide content of not more than 0.5 wt.% (Pentasil, zeolite-beta, aluminophosphate, mordenite, silicoaluminophosphate) (30 - 60 wt.%) )

 Zeolite is used in mixed cation-decationized form with a degree of exchange for a polyvalent cation (nickel, iron, aluminum, rare earth elements, chromium or a mixture thereof) of 70-85 wt.%, For hydrogen 15-25 wt.%.

 A catalyst based only on the hydrogen form of the zeolite (i.e., unmodified) has a low activity (see Example 10, Table 2).

 In the examples of preparation of the catalyst, we used a domestic high-silica zeolite CVM (pentasil group) with silicate module 37, (modified with polyvalent elements and unmodified).

 2. Hydrogenating components - one or more metals selected from the group: nickel, cobalt, molybdenum, tungsten (15-40 wt.%).

 3. Fillers or their mixture: boron oxide, zirconium oxide (1 - 4 wt.%).

 4. Binder component: alumina, crystalline silicon oxide, synthetic aluminosilicate, clay or a mixture thereof (the rest is up to 100%).

Cracking of heavy oil residues using the proposed catalyst
The processing of raw materials is carried out at a temperature of 340-450 ^o C, a space velocity of 1-3 h ^-1 , at atmospheric pressure, in the presence of inert gas (nitrogen, helium, argon, flue gases) with an inert gas / feed ratio of 250-1000 nl / l of raw materials, in the presence of hydrogen under a pressure of 0.1-10 MPa with a ratio of hydrogen / raw materials of 250-2000 nl / l of raw materials.

 The catalyst is prepared by mixing the components in a kneading machine, followed by molding the mass on a molding machine in the form of extrudates with a diameter of 2-4 mm.

 The catalyst is designed for low-temperature processing of desalted and dehydrated heavy crude oil (vacuum gas oil, fuel oil, tar, oil) in installations with a fixed catalyst bed.

 The catalyst is prepared as follows.

In a container with a stirrer and heating, a mixed solution of ammonium salt and a polyvalent element or a mixture thereof, or only a solution of ammonium salt (for the preparation of unmodified zeolite) is prepared and the calculated amount of zeolite Na-CVM is loaded with stirring. The ratio of solution / zeolite is 5/1. The temperature in the reactor was raised to 80-90 ^° C and the treatment was continued for 2 hours. Then, the zeolite was filtered off and washed on the filter with a three-fold volume of condensate. A cake of wet zeolite is loaded into the original container for re-ion exchange. The resulting zeolite is filtered off and washed on the filter with ten times the volume of condensate.

 To prepare the catalyst, the obtained zeolite is loaded into the kneading machine in the required ratio, the binder and the mass are mixed until homogeneous. Then add salts of hydrogenating metals, fillers and continue mixing until homogeneous. The mass is evaporated, molded on an extrusion molding machine with a matrix of 3-4 mm, the granules are dried in air, dried and calcined.

 From the description it follows that the technology for preparing the catalyst is simple and its production can be carried out at any catalyst factory.

 The catalyst samples were tested during the conversion of dehydrated and desalted oil and tar.

It was previously shown that when the diesel fraction 200-360 ^o C was passed through the catalyst under similar conditions, the formation of gas and gasoline was not observed. This indicates that the diesel fraction is not converted.

As follows from the description, the preparation of the catalyst according to this invention consists of two stages:
- preparation of a modified zeolite CVM:
- preparation of a catalyst based on the obtained zeolite.

Zeolite preparation
In a container with a stirrer and heating, 75 l of a mixed solution of ammonium salts and the corresponding polyvalent element or a mixture thereof are prepared (0.2 N for each salt). In the prepared solution, with stirring, load 15 kg of the initial zeolite Na-TsVM (PPP = 8.5 wt.%) With a Na ₂ O content of 3.5 wt.%. The temperature in the tank is raised to 80-90 ^o C and continue processing with constant stirring for 2 hours. Then the container is cooled, the zeolite is filtered off and washed on the filter with a three-fold volume of condensate. The wet zeolite cake from the filter is returned to the original container and a second treatment is carried out under similar conditions. After the second ion exchange, the zeolite is filtered off and washed with ten times the volume of condensate.

 Under the indicated conditions, samples of modified zeolite CVM in various polyvalent forms were prepared.

The characteristics of the obtained zeolite samples are presented in table 1
Based on the obtained modified forms of zeolite, catalysts were prepared and tested in accordance with the invention.

 The invention is illustrated by the examples set forth in the application.

 Example 1

10 kg of cake of wet zeolite CVM modified with Ni (NiSCVM) (PPP = 50 wt.%), 10.8 kg of aluminum hydroxide (PPP = 70 wt.%) Are loaded into a kneading machine, the mass is mixed until homogeneous. Then, 2.4 kg of nickel nitrate, 0.8 kg of ammonium molybdate, 3.1 kg of ammonium tungstate, 0.44 kg of boric acid and 0.54 kg of zirconyl nitrate are filled in. Stirring is continued until smooth. Then the mass is evaporated to a moisture suitable for molding (PPP = 40-43 wt.%), Formed on an extrusion machine through a die with a hole diameter of 3 mm, the granules are dried in air for 24 hours, dried at 120-140 ^o C for 6 hours and calcined at 530-550 ^o With 6 hours

The obtained catalyst of the following chemical composition, wt.%:
Zeolite NiNTSVM - 40
Al ₂ O ₃ - 26
Hydrogenation components - 30
B ₂ About ₃ - 2
ZrO ₂ - 2
Example 2

 The catalyst is prepared according to example 1, but take the zeolite CVM, modified Al (AlNTSVM).

The obtained catalyst of the following chemical composition, wt.%:
Zeolite AlNTSVM - 40
Al ₂ O ₃ - 26
Hydrogenation components - 30
B ₂ O ₃ - 2
ZrO ₂ - 2
Example 3

 The catalyst is prepared according to example 1, but they take the zeolite CVM, modified Ge (SeNTSVM).

The obtained catalyst of the following chemical composition, wt.%:
Zeolite SeNTSVM - 40
Al ₂ O ₃ - 26
Hydrogenation components - 30
B ₂ About ₃ - 2
ZrO ₂ - 2
Example 4

 The catalyst is prepared according to example 1, but they take the zeolite CVM. modified Fe (FeNTSVM).

The obtained catalyst of the following chemical composition, wt.%:
Zeolite FeНЦВМ - 40
Al ₂ O ₃ - 26
Hydrogenation components - 30
B ₂ About ₃ - 2
ZrO ₂ - 2
Example 5

 The catalyst is prepared according to example 1, but they take 7.5 kg of zeolite and 15 kg of aluminum hydroxide.

The obtained catalyst of the following chemical composition, wt.%:
Zeolite NiNTSVM - 30
Al ₂ O ₃ - 36
Hydrogenation components - 30
B ₂ O ₃ - 2
ZrO ₂ - 2
Example 6

 The catalyst is prepared according to example 1, but they take 12.5 kg of zeolite and 6.7 kg of aluminum hydroxide.

The obtained catalyst of the following chemical composition, wt.%:
Zeolite NiNTSVM - 50
Al ₂ O ₃ - 16
Hydrogenation components - 30
B ₂ About ₃ - 2
ZrO ₂ - 2
Example 7

 The catalyst is prepared according to example 1, but nickel nitrate is taken 2.4 kg, ammonium molybdate 0.8 kg, ammonium tungstate 1.6 kg, and aluminum hydroxide 15 kg.

The obtained catalyst of the following chemical composition, wt.%:
Zeolite - 40
Al ₂ O ₃ - 26
Hydrogenation components - 20
B ₂ About ₃ - 2
ZrO ₂ - 2
Example 8

 The catalyst is prepared according to example 1, but nickel nitrate is taken 6.3 kg, ammonium molybdate 0.8 kg, ammonium tungstate 3.1 kg, and aluminum hydroxide 7.5 kg.

The obtained catalyst of the following chemical composition, wt.%:
Zeolite - 40
Al ₂ O ₃ - 18
Hydrogenation components - 38
B ₂ About ₃ - 2
ZrO ₂ - 2
Example 9

 The catalyst is prepared according to example 1, but the zeolite FeNTSVM take 12.5 kg, aluminum oxide 3.3 kg, nickel nitrate 6.3 kg, ammonium molybdate 0.8 kg, ammonium tungstate 3.1 kg.

The obtained catalyst of the following chemical composition, wt.%:
Zeolite FeНЦВМ - 50
Al ₂ O ₃ - 8
Hydrogenation components - 38
B ₂ O ₃ - 2
ZrO ₂ - 2
Example 10

 The catalyst is prepared according to example 1, but they take the zeolite CVM unmodified (NCM).

 Example 11

 The catalyst is prepared according to example 1, but take the zeolite REE-U (prototype).

 The catalyst according to examples 1-11 was tested in atmospheric cracking of dehydrated and desalted West Siberian oil with a content of light oil products of 47 vol. % in a flow catalytic installation with a stationary catalyst bed. During the tests, the volumetric feed of the feedstock and the volumetric yield of catalysis were recorded, which under these test conditions was 91-94 vol.%.

The catalyst was fractionated according to Engler to a temperature of 300 ^o C in accordance with GOST for the distillation of oil at atmospheric pressure. A further increase in temperature causes decomposition of the residual product. The activity of the catalyst was evaluated by the yield of fractions up to 200 ^o C and up to 300 ^o C and the total increase in the yield of light petroleum products in vol.% In comparison with the feedstock. The test results are presented in table.2.

The catalyst according to example 4 was tested in atmospheric tar cracking at 360 ^o C and a volumetric feed rate of V = 2 h ^-1 , a yield of light oil products of 53 vol.% ^Was obtained.

The data obtained indicate the high efficiency of the proposed catalyst in direct oil refining. Depending on the composition of the catalyst at 370 ^o С and V-2 h ^{-1 the} yield of the fraction up to 200 ^o С is 22-27 vol.%, And the fraction up to 300 ^o С is 48-52 vol.%, While for the initial oil it is 19 vol.% and 39 vol.%, respectively. The total increase in the yield of light oil products to 300 ^o With is 13.0-33.3 vol.% Compared with the original oil.

 The catalyst based on the hydrogen form of the CVM zeolite is inactive (example 10), and the catalyst does not work on the basis of zeolite U (under these conditions) (example 11).

Cracking is recommended to be carried out at a temperature of 340-420 ^o C and a volumetric feed rate of V = 1-3 h ^-1 , which is confirmed by the following examples.

 Example 12

The catalyst of example 9 was tested in the process of cracking oil at 340 ^o With and V = 1 h ^-1 .

The yield of fractions up to 200 ^o C and 300 ^o C 25 and 51 vol.%, Respectively. The increase in the yield of the fraction up to 300 ^o C compared with the original oil is 30.8 vol.%.

 Example 13

The catalyst of example 9 was tested in the process of cracking oil at 420 ^o C and V = 3 h ^-1 .

The yield of fractions up to 200 ^o C and 300 ^o C 29 and 54 vol.% Respectively. The increase in the yield of the fraction up to 300 ^o with compared to the original oil is 38.5 vol.%.

 The implementation of the cracking process in a stream of inert gas (nitrogen) leads to a significant increase in the yield of light oil products, as evidenced by the following examples.

 Example 14

The catalyst of example 9 was tested in the process of cracking oil at 370 ^o C, V = 2 h ^-1 in a stream of nitrogen at a ratio of N ₂ , nl / l of feedstock = 250.

The yield of fractions up to 200 ^o C and 300 ^o C 30 and 61 vol.%, Respectively. The increase in the yield of the fraction to 300 ^o With compared to the original oil is 56.4 vol.%.

 Example 15

The catalyst of example 9 was tested in the process of cracking oil at 370 ^o C, V = 2 h ^-1 in a stream of nitrogen at a ratio of N ₂ , nl / l of feedstock = 1000.

The yield of fractions up to 200 ^o C and 300 ^o C 33 and 64 vol.%, Respectively, was obtained. The increase in the yield of the fraction to 300 ^o C is 67.1 vol.% Compared with the original oil.

 Moreover, as follows from examples 14 and 15, in a stream of nitrogen, the yield of mainly diesel fraction increases.

 Further intensification of cracking of heavy oil fractions is observed during the process in a stream of hydrogen, as evidenced by examples 16 and 17.

 Example 16

The catalyst of example 9 was tested in the process of cracking oil at 410 ^o C, V = 2 h ^-1 , a hydrogen pressure of 5 MPa and a ratio of H ₂ , nl / l of feedstock = 300. Received a liquid product with a yield of 93 vol.%. High conversion of the heavy part of the oil allowed to carry out the Angler distillation up to 360 ^o С. The yield of the fraction up to 200 ^o С and 360 ^o С was 40 and 80.3 vol.%. The increase in the yield of the fraction to 360 ^o C is 70.1 vol.%.

 Example 17

The catalyst of example 9 was tested under the conditions of example 16 with a ratio of H ₂ , nl / l of feed = 1000. A liquid product was obtained with a yield of 94 vol.%. The yield of fractions up to 200 ^o C and 360 ^o C amounted to 41 and 83.0 vol.%, Respectively. The increase in the yield of the fraction to 360 ^o C is 76.6 vol.%.

 Example 18

The catalyst of example 17 was tested at a hydrogen pressure of 10 MPa. Received a liquid product with a yield of 93 vol.%. The yield of the fraction up to 200 ^o C and 360 ^o C amounted to 42 and 87.75 vol.%, Respectively. The increase in the yield of the fraction to 360 ^o C is 86.6 vol.%.

Claims (3)

1. Cracking catalyst for desalted and dehydrated heavy petroleum feeds (vacuum gas oil, fuel oil, tar, oil) containing zeolite, a binder component, hydrogenation components and fillers, characterized in that it contains high silica zeolite modified with polyvalent elements with a molar ratio of SiO ₂ / Al ₂ O ₃ (mol / mol) 12-150 and a Na ₂ O content of not more than 0.5 wt. %, moreover, as a zeolite, the catalyst contains a zeolite selected from the group: pentasil, zeolite-beta, aluminophosphate, mordenite, silicoaluminophosphate, one or more metals selected from the group of nickel, cobalt, molybdenum, tungsten are used as hydrogenating components fillers use boron oxide (B ₂ O ₃ ), zirconium oxide (ZrO ₂ ), or a mixture thereof, alumina (Al ₂ O ₃ ), crystalline silicon dioxide (SiO ₂ ), synthetic aluminosilicate, clay, or their mixture as well as modifying irrigation entnyh elements use one or more elements selected from the group: Ni, Al, Ce, Fe, Cr, rare earth elements, with the following component ratio, wt. %:
Zeolite - 30 - 60
Hydrogenation components - 15 - 40
Fillers - 1 - 4
Binder Component - Else up to 100
2. The method of processing desalted and fat-free heavy crude oil (vacuum gas oil, fuel oil, hydron, oil) in the presence of a catalyst containing zeolite, a binder component, hydrogenation components, fillers, characterized in that the catalyst according to claim 1 and the process are used as a catalyst carried out at a temperature of 340-450 ^o C, a pressure of 0.1-10 MPa, a volumetric feed rate of 1-3 hours ^-1 .  3. The method according to p. 2, characterized in that the process is carried out in the presence of an inert gas (nitrogen, flue gas, helium, argon) with an inert gas / feed ratio = 250-1000 (nl / l). 4. The method according to p. 2, characterized in that the process is carried out in the presence of H ₂ at a ratio of H ₂ / feed = 250-2000 (nl / l).

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