Preparation method of lubricating oil

Abstract

The invention discloses a lubricating oil preparation method, which comprises: contacting a raw material containing waste rubber with a catalyst in a closed container in a hydrogen atmosphere, and carrying out a catalytic cracking reaction to obtain a lubricating oil-containing product, the catalyst comprises a carrier, an acidic component and an active component loaded on the surface of the carrier, the active component is selected from at least one of a ruthenium elementary substance, a rhodium elementary substance, a platinum elementary substance, a palladium elementary substance, an iridium elementary substance and a nickel elementary substance; the acidic component is selected from at least one of silicotungstic acid, ammonium metatungstate, phosphotungstic acid and tungstic acid. The invention discloses a new path for preparing the lubricating oil by utilizing the waste rubber through a carbon = carbon hydrogenation and carbon-carbon bond breakage strategy under a relatively mild condition. According to the path, new application of waste rubber catalytic conversion is developed through C = C hydrogenation and C-C bond fracture strategies, and a new method for synthesizing lubricating oil with important application value is provided.

Description

Technical Field

[0001] The present application relates to a method for preparing lubricating oil, and belongs to the field of chemical industry. Background Art

[0002] Rapid technological and economic development has greatly promoted the modernization of lifestyles, leading to an increase in commodity consumption and waste generation. Fossil fuel reserves are not inexhaustible, and the combustion of most conventional fuels is not environmentally friendly. Due to global warming and the rapid consumption of fossil fuels as energy and important raw materials, the development of renewable energy and waste recycling have received more attention. A large amount of waste rubber is generated every year around the world, including waste tires, rubber gloves, latex pillows, rubber balloons, rubber soles, etc. Most of the waste rubber is difficult to degrade. For example, waste tires usually take more than 10 years to degrade in landfills. The combustion of waste rubber produces toxic gases, which contain carcinogenic and mutagenic chemicals. Natural rubber and synthetic rubber are the main components of these rubber products. Reprocessing waste rubber to utilize long-chain hydrocarbons (its main components) may make it more economically efficient and more environmentally friendly, thereby helping to mitigate the threats posed by the reduction of fossil fuel reserves and climate change. Summary of the invention

[0003] The purpose of the present application is to provide a new route for preparing lubricating oil by utilizing waste rubber through carbon=carbon hydrogenation and carbon-carbon bond breaking strategies.

[0004] According to one aspect of the present application, a method for preparing a lubricating oil is provided, comprising the following steps:

[0005] The raw material containing waste rubber is contacted with a catalyst in a closed container under a hydrogen atmosphere to cause a catalytic cracking reaction to obtain a product containing lubricating oil;

[0006] The yield of lubricating oil is 30-95%.

[0007] The catalyst comprises a carrier and an active component supported on the surface of the carrier;

[0008] The active component is selected from at least one of ruthenium, rhodium, platinum, palladium, iridium and nickel;

[0009] The carrier is treated with acid;

[0010] The acid component used in the acid treatment is selected from at least one of silicotungstic acid, ammonium metatungstate, phosphotungstic acid and tungstic acid.

[0011] The waste rubber is selected from at least one of natural rubber, waste tires, rubber gloves, latex gloves, latex tubes, latex pillows, latex balloons, latex mattresses, latex caps, rubber plugs, rubber soles, and rubber gaskets.

[0012] The carrier is selected from at least one of zirconium oxide, fumed silica, nano-cerium oxide, and nano-aluminum oxide;

[0013] The size of the carrier is 20-200 nm.

[0014] The mass of the catalyst is 5 to 200% of the mass of the raw material;

[0015] Optionally, the mass of the catalyst is 10-100% of the mass of the raw material.

[0016] The pressure of the hydrogen atmosphere is 0.1-8 MPa;

[0017] Optionally, the pressure of the hydrogen atmosphere is 1 to 6 MPa;

[0018] Optionally, the pressure of the hydrogen atmosphere is 2-5 MPa.

[0019] The reaction is carried out in a high-pressure reactor, which is sealed at room temperature and normal atmospheric pressure, and the reaction atmosphere is replaced by argon, nitrogen or hydrogen. During the reaction, the pressure in the reactor is the high pressure generated by the thermal expansion of hydrogen.

[0020] The temperature of the catalytic cracking reaction is 120-350°C;

[0021] Optionally, the temperature of the catalytic cracking reaction is 180 to 300°C;

[0022] Optionally, the temperature of the catalytic cracking reaction is 200-280°C.

[0023] Too low a temperature will easily lead to low substrate conversion rate, while too high a temperature will lead to the production of gaseous products. Within a certain time range, the conversion rate increases with the increase of reaction time, but after the reaction time is extended to a certain time, the product will continue to break down into alkanes with shorter carbon chains as time goes on.

[0024] The catalytic cracking reaction time is 1h to 60h;

[0025] Optionally, the catalytic cracking reaction time is 2h to 30h;

[0026] Optionally, the catalytic cracking reaction time is 5h to 24h.

[0027] In the catalyst, the content of the active component is 5 to 10 wt%;

[0028] In the catalyst, the content of the acidic component is 1 to 30 wt%.

[0029] The preparation method of the catalyst comprises the following steps:

[0030] The support is immersed in a solution containing an acidic component, dried and calcined to obtain an acid-treated support, and the acid-treated support is immersed in a solution containing an active component precursor, dried and reduced to obtain the catalyst. It is recorded as active component / acidic component / support, such as Ru / SiWO3 / ZrO2.

[0031] The calcination temperature is 600-1000° C., the calcination time is 2-6 hours, and the calcination is carried out in air.

[0032] The reduction temperature is 200-350°C, and the reduction time is 2-6h;

[0033] The active component precursor is selected from at least one of RuCl3·xH2O, H2PtCl6·6H2O, PdCl2, RhCl3·3H2O, and IrCl3NiCl2·6H2O.

[0034] The advantages of this application are:

[0035] A new route is disclosed for preparing lubricating oil from waste rubber under mild conditions through carbon=carbon hydrogenation and carbon-carbon bond cleavage strategies. This route opens up new applications for catalytic conversion of waste rubber through C=C hydrogenation and C-C bond cleavage strategies, and provides a new method for synthesizing lubricating oil with important application value. DETAILED DESCRIPTION

[0036] The present application is described in detail below with reference to embodiments, but the present application is not limited to these embodiments.

[0037] Unless otherwise specified, the raw materials and catalysts in the examples of this application were purchased through commercial channels.

[0038] The analysis method in the examples of this application is as follows:

[0039] The liquid product was quantitatively analyzed by filtration, rotary evaporation and weighing.

[0040] The qualitative analysis of the liquid products was carried out by gel permeation chromatography (GPC) and gas chromatography-mass spectrometry (GC-MS).

[0041] Preparation Example 1

[0042] Taking Ru / 5%SiWO3 / ZrO2 as an example, the Ru / 5%SiWO3 / ZrO2 catalyst was prepared by the initial wet impregnation method. First, a certain amount of silicotungstic acid was dissolved in ultrapure water, and then a certain amount of m-ZrO2 was added, stirred for 10 minutes, and ultrasonically dispersed for 5 minutes. Then the beaker was sealed, impregnated at room temperature for 24 hours, and then dried in an oven at 110°C for 12 hours, and then placed in a muffle furnace and calcined at 800°C for 3 hours to obtain 5%SiWO3 / ZrO2. After that, RuCl3·xH2O was dissolved in ultrapure water as a precursor, and then a certain amount of 5%SiWO3 / ZrO2 was added, stirred for 10 minutes, and ultrasonically dispersed for 5 minutes. Then the beaker was sealed, and the metal precursor and the carrier were impregnated at room temperature for 24 hours, and then dried in an oven at 110°C for 12 hours. The impregnated catalyst was activated in a tube furnace at 250°C in a hydrogen atmosphere for 3 hours to reduce the Ru precursor to metallic Ru to prepare a Ru / 5%SiWO3 / ZrO2 catalyst.

[0043] The preparation process of other catalysts used in the examples of this application refers to the process of this preparation example.

[0044] Example 1

[0045] Catalyst pretreatment: 0.12g Ru / 5% SiWO3 / ZrO2 was reduced in a hydrogen atmosphere at 250℃ for 3h. In the reactor, 0.5g natural rubber and 0.1g Ru / 5% SiWO3 / ZrO2 were added respectively, replaced with nitrogen, then replaced with hydrogen, filled with hydrogen to a pressure of 4Mpa, reacted at 240℃ for 16h, cooled to room temperature after the reaction, and the liquid product was collected and weighed. The yield of lubricating oil was 95%.

[0046] Example 2

[0047] Catalyst pretreatment: 0.12g Ru / 5% SiWO3 / ZrO2 was reduced in a hydrogen atmosphere at 200℃ for 3h. In the reactor, 0.5g natural rubber and 0.1g Ru / 5% SiWO3 / ZrO2 were added respectively, replaced with nitrogen, then replaced with hydrogen, filled with hydrogen to a pressure of 4Mpa, reacted at 240℃ for 16h, cooled to room temperature after the reaction, and the liquid product was collected for analysis and weighing. The yield of lubricating oil was 74%.

[0048] Example 3

[0049] Catalyst pretreatment: 0.12g Ru / 5% SiWO3 / ZrO2 was reduced in a hydrogen atmosphere at 300℃ for 3h. In the reactor, 0.5g natural rubber and 0.1g Ru / 5% SiWO3 / ZrO2 were added respectively, replaced with nitrogen, then replaced with hydrogen, filled with hydrogen to a pressure of 4Mpa, reacted at 240℃ for 16h, cooled to room temperature after the reaction, and the liquid product was collected for analysis and weighing. The yield of lubricating oil was 65%.

[0050] Example 4

[0051] Catalyst pretreatment: 0.12g Ru / 5% PWO3 / ZrO2 was reduced in a hydrogen atmosphere at 250℃ for 3h. In the reactor, 0.5g natural rubber and 0.1g Ru / 5% PWO3 / ZrO2 were added respectively, replaced with nitrogen, then replaced with hydrogen, filled with hydrogen to a pressure of 4Mpa, reacted at 240℃ for 16h, cooled to room temperature after the reaction, and the liquid product was collected for analysis and weighing. The yield of lubricating oil was 68%.

[0052] Example 5

[0053] Catalyst pretreatment: 0.12g Ru / 5% HWO3 / ZrO2 was reduced in a hydrogen atmosphere at 250℃ for 3h. In the reactor, 0.5g natural rubber and 0.1g Ru / 5% HWO3 / ZrO2 were added respectively, replaced with nitrogen, then replaced with hydrogen, and filled with hydrogen to a pressure of 4Mpa. The reaction was carried out at 240℃ for 16h. After the reaction was completed, the reaction was cooled to room temperature, and the liquid product was collected for analysis and weighing. The yield of lubricating oil was 42%.

[0054] Example 6

[0055] Catalyst pretreatment: 0.12g Ru / 5%NWO3 / ZrO2 was reduced in a hydrogen atmosphere at 250℃ for 3h. In the reactor, 0.5g natural rubber and 0.1g Ru / 5%NWO3 / ZrO2 were added respectively, replaced with nitrogen, then replaced with hydrogen, and filled with hydrogen to a pressure of 4Mpa. The reaction was carried out at 240℃ for 16h. After the reaction was completed, the reaction was cooled to room temperature, and the liquid product was collected for analysis and weighing. The yield of lubricating oil was 73%.

[0056] Example 7

[0057] Catalyst pretreatment: 0.12g Ru / 10% SiWO3 / ZrO2 was reduced in a hydrogen atmosphere at 250℃ for 3h. In the reactor, 0.5g natural rubber and 0.1g Ru / 10% SiWO3 / ZrO2 were added respectively, replaced with nitrogen, then replaced with hydrogen, filled with hydrogen to a pressure of 4Mpa, reacted at 240℃ for 16h, cooled to room temperature after the reaction, and the liquid product was collected and weighed. The yield of lubricating oil was 63%.

[0058] Example 8

[0059] Catalyst pretreatment: 0.12g Ru / 15% SiWO3 / ZrO2 was reduced in a hydrogen atmosphere at 250℃ for 3h. In the reactor, 0.5g natural rubber and 0.1g Ru / 15% SiWO3 / ZrO2 were added respectively, replaced with nitrogen, then replaced with hydrogen, filled with hydrogen to a pressure of 4Mpa, reacted at 240℃ for 16h, cooled to room temperature after the reaction, and the liquid product was collected and weighed. The yield of lubricating oil was 50%.

[0060] Example 9

[0061] Catalyst pretreatment: 0.12g Ru / 30% SiWO3 / ZrO2 was reduced in a hydrogen atmosphere at 250℃ for 3h. In the reactor, 0.5g natural rubber and 0.1g Ru / 30% SiWO3 / ZrO2 were added respectively, replaced with nitrogen, then replaced with hydrogen, filled with hydrogen to a pressure of 4Mpa, reacted at 240℃ for 16h, cooled to room temperature after the reaction, and the liquid product was collected and weighed. The yield of lubricating oil was 38%.

[0062] Example 10

[0063] Catalyst pretreatment: 0.12g Ru / 5% SiWO3 / ZrO2 was reduced in a hydrogen atmosphere at 250℃ for 3h. In the reactor, 0.5g natural rubber and 0.1g Ru / 5% SiWO3 / ZrO2 were added respectively, replaced with nitrogen, then replaced with hydrogen, and filled with hydrogen to a pressure of 3Mpa. The reaction was carried out at 240℃ for 16h. After the reaction was completed, the reaction was cooled to room temperature, and the liquid product was collected and weighed. The yield of lubricating oil was 66%.

[0064] Embodiment 11

[0065] Catalyst pretreatment: 0.12g Ru / 5% SiWO3 / ZrO2 was reduced in a hydrogen atmosphere at 250℃ for 3h. In the reactor, 0.5g natural rubber and 0.1g Ru / 5% SiWO3 / ZrO2 were added respectively, replaced with nitrogen, then replaced with hydrogen, filled with hydrogen to a pressure of 5Mpa, reacted at 240℃ for 16h, cooled to room temperature after the reaction, and the liquid product was collected and weighed. The yield of lubricating oil was 70%.

[0066] Example 12

[0067] Catalyst pretreatment: 0.12g Ru / 5% SiWO3 / ZrO2 was reduced in a hydrogen atmosphere at 250℃ for 3h. In the reactor, 0.5g natural rubber and 0.1g Ru / 5% SiWO3 / ZrO2 were added respectively, replaced with nitrogen, then replaced with hydrogen, filled with hydrogen to a pressure of 4Mpa, reacted at 280℃ for 2h, cooled to room temperature after the reaction, and the liquid product was collected and weighed. The yield of lubricating oil was 46%.

[0068] Example 13

[0069] Catalyst pretreatment: 0.12g Ru / 5% SiWO3 / ZrO2 was reduced in a hydrogen atmosphere at 250℃ for 3h. In the reactor, 0.5g natural rubber and 0.1g Ru / 5% SiWO3 / ZrO2 were added respectively, replaced with nitrogen, then replaced with hydrogen, and filled with hydrogen to a pressure of 4Mpa. The reaction was carried out at 250℃ for 16h. After the reaction was completed, the reaction was cooled to room temperature, and the liquid product was collected and weighed. The yield of lubricating oil was 69%.

[0070] Embodiment 14

[0071] Catalyst pretreatment: 0.12g Ru / 5% SiWO3 / ZrO2 was reduced in a hydrogen atmosphere at 250℃ for 3h. In the reactor, 0.5g natural rubber and 0.1g Ru / 5% SiWO3 / ZrO2 were added respectively, replaced with nitrogen, then replaced with hydrogen, and filled with hydrogen to a pressure of 4Mpa. The reaction was carried out at 245℃ for 16h. After the reaction was completed, the reaction was cooled to room temperature, and the liquid product was collected and weighed. The yield of lubricating oil was 81%.

[0072] Embodiment 15

[0073] Catalyst pretreatment: 0.12g Ru / 5% SiWO3 / ZrO2 was reduced in a hydrogen atmosphere at 250℃ for 3h. In the reactor, 0.5g natural rubber and 0.1g Ru / 5% SiWO3 / ZrO2 were added respectively, replaced with nitrogen, then replaced with hydrogen, filled with hydrogen to a pressure of 4Mpa, reacted at 235℃ for 16h, cooled to room temperature after the reaction, and the liquid product was collected and weighed. The yield of lubricating oil was 35%.

[0074] Example 16

[0075] Catalyst pretreatment: 0.12g Ru / 5% SiWO3 / ZrO2 was reduced in a hydrogen atmosphere at 250℃ for 3h. In the reactor, 0.5g natural rubber and 0.1g Ru / 5% SiWO3 / ZrO2 were added respectively, replaced with nitrogen, then replaced with hydrogen, and filled with hydrogen to a pressure of 4Mpa. The reaction was carried out at 230℃ for 16h. After the reaction was completed, the reaction was cooled to room temperature, and the liquid product was collected and weighed. The yield of lubricating oil was 18%.

[0076] Embodiment 17

[0077] Catalyst pretreatment: 0.12g Ru / 5% SiWO3 / ZrO2 was reduced in a hydrogen atmosphere at 250℃ for 3h. In the reactor, 0.5g natural rubber and 0.1g Ru / 5% SiWO3 / ZrO2 were added respectively, replaced with nitrogen, then replaced with hydrogen, and filled with hydrogen to a pressure of 4Mpa. The reaction was carried out at 240℃ for 14h. After the reaction was completed, the reaction was cooled to room temperature, and the liquid product was collected and weighed. The yield of lubricating oil was 66%.

[0078] Embodiment 18

[0079] Catalyst pretreatment: 0.12g Ru / 5% SiWO3 / ZrO2 was reduced in a hydrogen atmosphere at 250℃ for 3h. In the reactor, 0.5g natural rubber and 0.1g Ru / 5% SiWO3 / ZrO2 were added respectively, replaced with nitrogen, then replaced with hydrogen, and filled with hydrogen to a pressure of 4Mpa. The reaction was carried out at 240℃ for 18h. After the reaction was completed, the reaction was cooled to room temperature, and the liquid product was collected and weighed. The yield of lubricating oil was 86%.

[0080] Embodiment 19

[0081] Catalyst pretreatment: 0.12g Ru / 5% SiWO3 / ZrO2 was reduced in a hydrogen atmosphere at 250℃ for 3h. In the reactor, 0.5g natural rubber and 0.1g Ru / 5% SiWO3 / ZrO2 were added respectively, replaced with nitrogen, then replaced with hydrogen, filled with hydrogen to a pressure of 4Mpa, reacted at 240℃ for 20h, cooled to room temperature after the reaction, and the liquid product was collected and weighed. The yield of lubricating oil was 78%.

[0082] Embodiment 20

[0083] Catalyst pretreatment: 0.24g Ru / 5% SiWO3 / ZrO2 was reduced in a hydrogen atmosphere at 250℃ for 3h. In the reactor, 1.0g natural rubber and 0.2g Ru / 5% SiWO3 / ZrO2 were added respectively, replaced with nitrogen, then replaced with hydrogen, filled with hydrogen to a pressure of 4Mpa, reacted at 240℃ for 16h, cooled to room temperature after the reaction, and the liquid product was collected and weighed. The yield of lubricating oil was 90%.

[0084] Embodiment 21

[0085] Catalyst pretreatment: 0.24g Ru / 5% SiWO3 / ZrO2 was reduced in a hydrogen atmosphere at 250℃ for 3h. In the reactor, 1.0g natural rubber and 0.2g Ru / 5% SiWO3 / ZrO2 were added respectively, replaced with nitrogen, then replaced with hydrogen, and filled with hydrogen to a pressure of 4Mpa. The reaction was carried out at 250℃ for 16h. After the reaction was completed, the reaction was cooled to room temperature, and the liquid product was collected and weighed. The yield of lubricating oil was 72%.

[0086] Embodiment 22

[0087] Catalyst pretreatment: 0.24g Ru / 5%SiWO3 / ZrO2 was reduced in a hydrogen atmosphere at 250℃ for 3h. In the reactor, 0.5g rubber tire and 0.2g Ru / 5%SiWO3 / ZrO2 were added respectively, replaced with nitrogen, then replaced with hydrogen, filled with hydrogen to a pressure of 4Mpa, reacted at 240℃ for 16h, cooled to room temperature after the reaction, and the liquid product was collected and weighed. The yield of lubricating oil was 53%.

[0088] Embodiment 23

[0089] Catalyst pretreatment: 0.24g Ru / 5% SiWO3 / ZrO2 was reduced in a hydrogen atmosphere at 250℃ for 3h. In the reactor, 0.5g rubber gloves and 0.2g Ru / 5% SiWO3 / ZrO2 were added respectively, replaced with nitrogen, then replaced with hydrogen, filled with hydrogen to a pressure of 4Mpa, reacted at 240℃ for 16h, cooled to room temperature after the reaction, and the liquid product was collected and weighed. The yield of lubricating oil was 76%.

[0090] Embodiment 24

[0091] Catalyst pretreatment: 0.24g Ru / 5% SiWO3 / ZrO2 was reduced in a hydrogen atmosphere at 250℃ for 3h. In the reactor, 0.5g latex pillow and 0.2g Ru / 5% SiWO3 / ZrO2 were added respectively, replaced with nitrogen, then replaced with hydrogen, filled with hydrogen to a pressure of 4Mpa, reacted at 240℃ for 16h, cooled to room temperature after the reaction, and the liquid product was collected and weighed. The yield of lubricating oil was 85%.

[0092] Embodiment 25

[0093] Catalyst pretreatment: 0.12g Ni / 5%SiWO3 / ZrO2 was reduced in a hydrogen atmosphere at 450℃ for 3h. In the reactor, 0.5g natural rubber and 0.1g Ni / 5%SiWO3 / ZrO2 were added respectively, replaced with nitrogen, then replaced with hydrogen, filled with hydrogen to a pressure of 4Mpa, reacted at 240℃ for 16h, cooled to room temperature after the reaction, and the liquid product was collected and weighed. The yield of lubricating oil was 45%.

[0094] Embodiment 26

[0095] Catalyst pretreatment: 0.12g Pt / 5%SiWO3 / ZrO2 was reduced in a hydrogen atmosphere at 250℃ for 3h. In the reactor, 0.5g natural rubber and 0.1g Pt / 5%SiWO3 / ZrO2 were added respectively, replaced with nitrogen, then replaced with hydrogen, and filled with hydrogen to a pressure of 4Mpa. The reaction was carried out at 240℃ for 16h. After the reaction was completed, the reaction was cooled to room temperature, and the liquid product was collected and weighed. The yield of lubricating oil was 64%.

[0096] Embodiment 27

[0097] Catalyst pretreatment: 0.12g Pt / SiO2 was reduced in a hydrogen atmosphere at 250℃ for 3h. In the reactor, 0.5g natural rubber and 0.1g Pt / SiO2 were added respectively, replaced with nitrogen, then replaced with hydrogen, and filled with hydrogen to a pressure of 4Mpa. The reaction was carried out at 240℃ for 16h. After the reaction was completed, the reaction was cooled to room temperature, and the liquid product was collected and weighed. The yield of lubricating oil was 51%.

[0098] The above are only a few embodiments of the present application and do not constitute any form of limitation to the present application. Although the present application is disclosed as above with preferred embodiments, it is not intended to limit the present application. Any technician familiar with the profession, without departing from the scope of the technical solution of the present application, using the technical content disclosed above to make slight changes or modifications are equivalent to equivalent implementation cases and fall within the scope of the technical solution.

Claims

1. A method for preparing lubricating oil, characterized in that: The following steps are involved: The raw material containing waste rubber is contacted with a catalyst in a closed container under a hydrogen atmosphere to cause a catalytic cracking reaction to obtain a product containing lubricating oil; The catalyst comprises a carrier and an active component supported on the surface of the carrier; The active component is selected from at least one of ruthenium, rhodium, platinum, palladium, iridium and nickel; The carrier is treated with acid; The acid component used in the acid treatment is selected from at least one of silicotungstic acid, ammonium metatungstate, phosphotungstic acid and tungstic acid.

2. The method for preparing lubricating oil according to claim 1, characterized in that: The waste rubber is selected from at least one of natural rubber, waste tires, rubber gloves, latex gloves, latex tubes, latex pillows, latex balloons, latex mattresses, latex caps, rubber plugs, rubber soles, and rubber gaskets.

3. The method for preparing lubricating oil according to claim 1, characterized in that: The carrier is selected from at least one of zirconium oxide, fumed silica, nano-cerium oxide, and nano-aluminum oxide; The size of the carrier is 20-200 nm.

4. The method for preparing lubricating oil according to claim 1, characterized in that: The mass of the catalyst is 5 to 200% of the mass of the raw material; Preferably, the mass of the catalyst is 10-100% of the mass of the raw material.

5. The method for preparing lubricating oil according to claim 1, characterized in that: The pressure of the hydrogen atmosphere is 0.1-8 MPa; Preferably, the pressure of the hydrogen atmosphere is 1 to 6 MPa; Preferably, the pressure of the hydrogen atmosphere is 2-5 MPa.

6. The method for preparing lubricating oil according to claim 1, characterized in that: The temperature of the catalytic cracking reaction is 120-350°C; Preferably, the temperature of the catalytic cracking reaction is 180-300°C; Preferably, the temperature of the catalytic cracking reaction is 200-280°C.

7. The method for preparing lubricating oil according to claim 1, characterized in that: The catalytic cracking reaction time is 1h to 60h; Preferably, the catalytic cracking reaction time is 2h to 30h; Preferably, the catalytic cracking reaction time is 5 h to 24 h.

8. The method for preparing lubricating oil according to claim 1, characterized in that: In the catalyst, the content of the active component is 5 to 10 wt%; In the catalyst, the content of the acidic component is 1 to 30 wt%.

9. The method for preparing lubricating oil according to claim 1, characterized in that: The preparation method of the catalyst comprises the following steps: The carrier is immersed in a solution containing an acidic component, dried and calcined to obtain an acid-treated carrier, and the acid-treated carrier is immersed in a solution containing an active component precursor, dried and reduced to obtain the catalyst.

10. The method for preparing lubricating oil according to claim 9, characterized in that: The active component precursor is selected from at least one of RuCl3·xH2O, H2PtCl6·6H2O, PdCl2, RhCl3·3H2O, and IrCl3NiCl2·6H2O.