Process for producing naphthenic rubber extension oil by hydrogenation

Abstract

The present invention discloses a process for producing cyclopentane rubber filler oil by hydrogenation. Cyclopentane vacuum distillate oil is used as raw material, and firstly, a hydrogenation treatment-hydrodecondensation reaction is carried out, and the effluent of the hydrogenation treatment-hydrodecondensation reaction is subjected to high-pressure stripping to remove H that has an impact on the precious metal catalyst. 2 S and NH 3 After removing impurities, it enters the deep supplementary refining reaction zone to improve the stability of the oil. The method of the present invention can obtain high-quality cycloalkyl rubber filler oil products, while producing high-quality special oil products as by-products, and greatly reduces the energy consumption caused by the two-stage method of boosting-depressurization-boosting, heating-cooling-heating, and has the advantages of simple process and small footprint.

Description

Technical Field

[0001] The present invention relates to a process for producing naphthenic rubber filler oil by hydrogenation, specifically a process for producing naphthenic special oil products by using naphthenic vacuum distillate oil as raw material through a two-stage process of hydrogenation treatment-hydrodecondensation-high pressure hydrogen stripping / supplementary refining. Background Art

[0002] Cycloalkane crude oil has the characteristics of high density, high viscosity, low wax content, high aromatic and cycloalkane content, and low pour point. It is often used as a raw material to produce low-condensation lubricant base oil that does not require viscosity-temperature performance, such as transformer oil, refrigeration oil, rubber filler oil, etc. The traditional production of lubricant base oil adopts solvent technology. The two main steps are solvent refining to remove non-ideal components such as aromatics, and solvent dewaxing to ensure the low-temperature flow properties of the base oil. Nowadays, the technology of hydrogenation for producing lubricating oil is developing rapidly. The hydrogenation method refers to the process method of producing lubricating base oil by hydrogenation treatment or hydrocracking-hydrogenation decondensation or isodewaxing-hydrogenation refining combined process. The hydrogenation method has the advantages of high product quality, no environmental problems, and high base oil yield, and gradually replaces the traditional solvent process.

[0003] In the prior art, a variety of hydrogenation processes can be used to produce cycloalkyl lubricating base oils. CN1990833A discloses a method for producing transformer oil using cycloalkyl oil as raw material through a two-stage process of hydrogenation treatment-hydrogenation refining. This method does not improve the pour point and requires the selection of suitable raw materials to obtain the ideal product. CN1676585A reports a method for producing lubricating base oil by hydrogenation treatment-hydrogenation decondensation-supplementary refining. The hydrogenation product of this method must be subjected to gas-liquid separation before the liquid product can enter the hydrodecondensation process. CN161376838A introduces a method for producing lubricating base oil by a two-stage hydrogenation process of hydrogenation treatment-hydrogenation decondensation-supplementary refining. In this method, the hydrogenation product does not need to be separated and directly enters the hydrodecondensation and supplementary refining reaction zone.

[0004] Shell has announced a method of using high-pressure steam stripping to directly remove H2S and NH3 from hydrotreated products, which then enters precious metal hydrodewaxing and supplementary refining reactors to produce cyclopentane rubber filler oil. The method has three industrial applications in China, but since the cold high-fraction oil containing H2S and NH3 without deep dearomatization is directly incorporated into the distillation system, all products have poor color and stability. Summary of the invention

[0005] In view of the shortcomings of the prior art, the present invention provides a process for producing cycloalkyl rubber filler oil by hydrogenation. Specifically, it is a method for producing cycloalkyl special oil products by using cycloalkyl vacuum distillate oil as raw material through a two-stage process of hydrogenation treatment-hydrodecondensation-high-pressure hydrogen stripping / supplementary refining.

[0006] A process for producing cycloalkyl rubber filler oil by hydrogenation of the present invention comprises the following contents:

[0007] (1) After the cycloalkyl vacuum distillate is mixed with hydrogen, it enters the hydroprocessing reaction zone and sequentially contacts with a hydroprotection catalyst, a hydrofining catalyst and a hydromodification catalyst to carry out a hydrogenation reaction, wherein the hydromodification catalyst contains amorphous silica-alumina and a modified Y molecular sieve;

[0008] (2) the hydrotreatment effluent obtained in step (1) enters the hydrodegradation reaction zone, contacts and reacts with a hydrodegradation catalyst, and selectively cracks the straight-chain alkanes that have the greatest impact on the pour point of the product, thereby reducing the pour point of the product;

[0009] (3) The hydrodecondensate obtained in step (2) enters a high-pressure stripping tower from the top, and hydrogen is injected into the bottom of the tower as a stripping medium. After stripping, a bottom oil from which H2S and NH3 are removed and a top effluent containing H2S, NH3, hydrogen and part of light oil are obtained;

[0010] (4) The top effluent obtained in step (3) containing H2S, NH3, hydrogen and part of the light oil enters a cold high-pressure separator after heat exchange, and the cold high-fraction oil containing H2S and NH3 enters a cold low-fraction to separate the low-fraction gas, and then the cold low-fraction oil enters a H2S removal stripping tower to remove H2S and NH3, and enters a supplementary refining reaction zone after pressure increase and heat exchange;

[0011] (5) The high-pressure stripping tower bottom oil obtained in step (3) is mixed with hydrogen and then enters the supplementary refining reaction zone together with the cold low-fraction oil from which H2S and NH3 are removed to undergo a deep dearomatization reaction to improve product stability;

[0012] (6) The reaction effluent obtained in step (5) enters a separation system to obtain cycloalkyl specialty oil products with a pour point that meets the requirements and good stability, and a series of light white oils that meet the technical index requirements of light white oil (II) in NB / SH / T 0913-2015.

[0013] Furthermore, in step (3), the high-pressure stripping tower includes a packing, such as a rolled hole θ ring packing. The selection of the packing is common knowledge for those skilled in the art. Preferably, a ZnO bed is also provided at the lower part of the packing zone, and the ZnO bed can be used to remove a small amount of H2S that is not stripped cleanly due to operation fluctuations. The operating conditions of the high-pressure stripping tower are well known to those skilled in the art. The operating conditions of the high-pressure stripping tower include: a stripping temperature of 150 to 400°C, preferably the outlet temperature of the hydrodecondensation reaction zone, a stripping pressure that is the same as the pressure of the hydrodecondensation reaction zone, and a hydrogen consumption that is higher than the chemical hydrogen consumption of the hydrotreatment and the hydrodecondensation reaction, preferably equivalent to the sum of the chemical hydrogen consumption of the hydrotreatment and the hydrodecondensation reaction and the dissolved hydrogen of the first-stage hydrogenation system.

[0014] Furthermore, the cold high-fraction gas phase obtained in step (4) is selectively de-H2Sed and then re-enters the hydroprocessing reactor as circulating hydrogen.

[0015] Furthermore, the naphthenic distillate oil can be at least one of naphthenic distillate oil, coal tar hydrocracking tail oil or catalytic cracking diesel fraction. The aromatic content of the naphthenic distillate is generally 30 to 99 wt%, and the density at 20°C is generally 0.923 to 0.955 g / cm 3 The distillation range of the cycloalkane distillate oil raw material is any range consisting of any two values ​​within the range of 140 to 600°C; preferably, the initial distillation point of the cycloalkane distillate oil is 140 to 350°C, and the final distillation point is 400 to 600°C.

[0016] Furthermore, the hydrotreating catalyst described in step (1) is a conventional hydrotreating catalyst in the art, such as a diesel hydrotreating catalyst or a hydrocracking pretreatment catalyst. Hydrotreating catalysts generally use Group VIB and / or Group VIII metals as active components and use alumina or silicon-containing alumina as a carrier. Group VIB metals are generally Mo and / or W, and Group VIII metals are generally Co and / or Ni. Based on the weight of the catalyst, the content of Group VIB metals is 10wt% to 50wt% in terms of oxide, and the content of Group VIII metals is 3 to 15wt% in terms of oxide; its properties are as follows: specific surface area is 100 to 350m 2 / g, pore volume is 0.15~0.6mL / g. Commercial catalysts that can be selected include 3936, 3996, FF-16, FF-26, FF-36, FF-46, FF-56, FF-66 and other hydrofining catalysts developed by Fushun Petrochemical Research Institute of Sinopec. It can also be a catalyst with similar functions developed by foreign catalyst companies, such as UOP's HC-K, HC-P catalysts, Topsoe's TK-555, TK-565 catalysts, and AKZO's KF-847, KF-848, etc.

[0017] Furthermore, the hydro-modification catalyst contains amorphous silica-alumina and modified Y molecular sieve. Based on the weight of the catalyst, the hydro-modification catalyst contains 20wt% to 60wt% amorphous silica-alumina, 5wt% to 25wt% modified Y zeolite, 10wt% to 30wt% of Group VIB metals in terms of oxides, and 4wt% to 15wt% of Group VIII metals in terms of oxides. The specific surface area of ​​the hydro-modification catalyst is generally 220 to 300m 2 / g, pore volume is 0.3-0.6mL / g, pore volume with pore diameter of 3-10nm accounts for 75%-95% of the total pore volume, preferably 85%-95%, infrared acidity is 0.30-0.5mmol / g. The properties of the amorphous silica-alumina used are as follows: containing 10wt%-60wt% of silicon oxide, specific surface area of ​​400-650m 2 / g, pore volume of 1.0-1.8mL / g, infrared acidity of 0.34-0.50mmol / g, pore volume of pores with a pore diameter of 4-10nm accounts for 85%-95% of the total pore volume, and pore volume of >15nm accounts for less than 5% of the total pore volume; the preferred properties are as follows: containing 10wt%-35wt% of silicon oxide, specific surface area of ​​530-650m 2 / g, pore volume is 1.2-1.5mL / g. The modified Y zeolite has the following properties: SiO2 / Al2O3 molar ratio is 40-60, unit cell constant is 2.425-2.440nm, relative crystallinity is 80-100%, infrared acidity is 0.1-0.5mmol / g, among which medium-strong acid at 250-550℃ is concentrated, accounting for 60-70% of the total acid, and specific surface area is 600-900m 2 / g, pore volume 0.3~0.6mL / g, of which the pore volume of secondary mesopores of 4~15nm accounts for 40%~50% of the total pore volume. The hydrogenation reforming catalyst may also contain one or more of the components such as alumina, zirconium oxide, titanium oxide, etc.

[0018] Furthermore, the hydrodegassing catalyst described in step (2) can be selected from the commonly used hydrodegassing catalysts in the art, which can be commercial hydrodegassing catalysts, such as 3881 and FDW-3 catalysts developed by Sinopec Fushun Petrochemical Research Institute, or can be prepared according to general knowledge in the art. The hydrodegassing catalyst contains ZSM-5 molecular sieve. Based on the weight of the catalyst, the content of ZSM-5 molecular sieve is 50wt% to 85wt%, NiO and / or CoO is 1.0 wt% to 8.0 wt%, and the rest is a binder.

[0019] Furthermore, the supplementary refining catalyst loaded in the supplementary refining reaction zone is a conventional reduction type hydrogenation refining catalyst, and its active metal is one or two of Pt and Pd, or nickel. The weight content of active metal in the precious metal catalyst is generally 0.05% to 1%, and the weight content of nickel in the reduced nickel catalyst as oxide is 30% to 80%; the catalyst carrier is generally Al2O3 or Al2O3-SiO2, and can also selectively contain one or more of P, Ti, B, and Zr as an auxiliary agent. The catalyst needs to be conventionally reduced before use to ensure that the hydrogenation active metal is in a reduced state during the reaction. Ordinary commercial catalysts in this field can be selected, or prepared according to ordinary methods in this field.

[0020] Further, the operating conditions of the hydroprocessing reaction zone are: hydrogen partial pressure 5.0-18.0 MPa, preferably 10.0-16.0 MPa; reaction temperature 230-430°C, preferably 350-410°C; hydrogen-to-oil volume ratio 200-1500, preferably 600:1-1000:1; volume space velocity 0.1-10.0 h -1 , preferably 0.3 h -1 ~0.5h -1 The loading ratio of the hydrotreating catalyst to the hydrorefining catalyst in the hydrotreating reaction zone is 1:9 to 9:1, preferably 4:6 to 6:4.

[0021] Furthermore, the operating conditions of the hydrocondensation reaction zone are: hydrogen partial pressure 5.0-18.0 MPa, preferably 10.0-16.0 MPa; reaction temperature 230-430°C, preferably 300-410°C; hydrogen-to-oil volume ratio 200-1500, preferably 500:1-1000:1; volume space velocity 0.1-10.0 h -1 , preferably 0.3 h -1 ~1.0h -1 ;

[0022] Further, the reaction conditions of the supplementary refining reaction zone are: reaction temperature is 200°C to 300°C, preferably 210°C to 280°C, hydrogen partial pressure is 6.0MPa to 18.0MPa, preferably 10.0 to 15.0MPa, volume space velocity is 0.2h -1 ~3.0h -1 , preferably 0.3h -1 ~0.6h -1 , the volume ratio of hydrogen to oil is 400:1 to 1500:1, preferably 600:1 to 800:1.

[0023] Furthermore, the hydroprocessing reaction zone and the hydrodecondensation reaction zone may be arranged in one reactor, or respectively arranged in two reactors.

[0024] Furthermore, the cycloalkyl special oil product obtained in step (6) includes one or more of transformer oil, refrigeration oil and a series of rubber filler oils.

[0025] Compared with the prior art, the method of the present invention has the following beneficial effects:

[0026] 1. The two-stage hydrogenation process of high-pressure hydrogen stripping, hydrotreatment, hydrodecondensation / deep supplementary refining is adopted, which avoids the need to set up two sets of fractionation systems in the traditional two-stage hydrogenation process to avoid the influence of H2S and NH3 on the precious metal catalyst. At the same time, most of the reaction feed (>85w%) of the two-stage hydrogenation process of high-pressure hydrogen stripping, hydrotreatment, hydrodecondensation and deep supplementary refining is a one-time pressure-raising process, which avoids the pressure-raising, pressure-reducing and re-pressurizing process of all raw oil between the two reaction zones of the traditional two-stage process device, saving electricity consumption. At the same time, the stripping hydrogen injected at the bottom of the high-pressure stripping tower is also a part of the supplementary hydrogen entering the circulating hydrogen system of the hydrotreatment device; the operating temperature of the high-pressure stripping tower is adjusted, and the bottom effluent can directly enter the supplementary refining reactor, and there is no need to set up an isomerized dewaxing feed heating furnace, which avoids the energy loss in the process of heating, cooling and reheating of all reaction products in the traditional two-stage process, saving electricity consumption and fuel gas consumption, and saving land.

[0027] 2. The effluent from the top of the high-pressure stripping tower enters the cold high-pressure separator after heat exchange. After separating the gas phase circulating hydrogen, the cold high-fraction oil containing H2S and NH3 is depressurized and enters the cold low-pressure separator to separate the low-fraction gas. The cold low-fraction oil enters the conventional H2S removal stripping tower to remove H2S and NH3, and enters the supplementary refining reactor after heat exchange. This solves the problem of the Shell process cold high-fraction oil directly entering the distillation system, which affects the product color and stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a process flow diagram of the method of the present invention. DETAILED DESCRIPTION

[0029] The method of the present invention is described in more detail below with reference to the accompanying drawings and specific embodiments.

[0030] Combination Figure 1The method for producing cycloalkyl rubber filling oil by hydrogenation of the present invention is as follows: the cycloalkyl vacuum distillate oil passes through pipeline 1, is mixed with the circulating hydrogen of pipeline 2, and first enters the hydrotreatment reaction zone 3 to carry out desulfurization, denitrogenation, deoxygenation and aromatic saturation reaction; then the hydrotreatment product 4 enters the hydrodecondensation reaction zone 5 to selectively crack the straight-chain alkanes in the product that have the greatest influence on the pour point of the product; then the hydrodecondensation product 6 enters the high-pressure hydrogen stripping tower 7, and the stripping hydrogen 8 is blown into the bottom of the tower to obtain the tower bottom oil 9 from which H2S and NH3 are removed, and the top of the high-pressure stripping tower enters the separation system 10 of the hydrotreatment-hydrodecondensation section, and the separation system 10 generally includes a high-pressure separator and a low-pressure separator; the separated gas phase is used as the circulating hydrogen through the pipeline Line 2 returns to the hydrotreating reaction system, and the liquid product 11 enters the H2S removal stripping tower 12. The bottom oil 13 from which H2S and NH3 have been removed is pressurized and heat exchanged, and then mixed with the circulating hydrogen 15, new hydrogen 14 and the high-pressure stripping tower bottom oil 9 of the supplementary refining section and directly enters the supplementary refining reactor 16 for deep dearomatization reaction to improve the photothermal stability of the product. The supplementary refining reaction product 17 enters the separation system 18, which generally includes a high-pressure separator and a low-pressure separator. The low-pressure oil enters the fractionation system 19, which includes a normal pressure fractionation tower and a vacuum fractionation tower to obtain light naphtha, light white oil and cycloalkyl products (including transformer oil, refrigeration oil and a series of cycloalkyl rubber filler oils).

[0031] The specific contents and effects of the method of the present invention are described below by means of specific embodiments.

[0032] The following examples will further illustrate the method provided by the present invention, but the scope of the present invention is not limited thereby. The properties of the raw materials treated by the present invention are shown in Table 1, and the physical and chemical properties of the catalyst used are shown in Table 2.

[0033] Table 1 Raw material properties

[0034]

[0035] Table 2 Physical and chemical properties of catalysts

[0036]

[0037] Example 1

[0038] The raw material is the naphthenic base oil listed in Table 1, and the physical and chemical properties of the catalyst are shown in Table 2. The hydroprocessing zone is filled with a series of hydroprotective agents, hydrofining catalysts and hydromodification catalysts, where the series of hydroprotective agents: hydrofining catalysts: hydromodification catalysts = 1:5.5:3.5 (volume). See the principle flow chart Figure 1 The process conditions and test results are shown in Tables 3 and 4.

[0039] Example 2

[0040] The raw materials are the cycloalkyl oil listed in Table 1, and the same catalyst as in Example 1 is used. Figure 1 The process conditions and tests are shown in Tables 3 and 4.

[0041] Comparative Example 1

[0042] Comparative Example 1 adopts the traditional two-stage hydrogenation process. The process flow is as follows: Hydrogenation treatment - Hydrogen decondensation product first enters the hot high-pressure separator, and then enters the cold high-pressure separator after gas phase heat exchange, the cold high-fraction gas phase enters the circulating hydrogen system, the cold high-fraction oil enters the cold low-fraction after decompression, and the top of the separator is the low-fraction gas; the hot high-fraction oil enters the hot low-fraction after decompression, and the top is the low-fraction gas; the hot low-fraction oil (most of the product) and the cold low-fraction oil are mixed and then all enter the dehydrogen sulfide stripping tower (pressure is about 1MPa), a small amount of hydrogen sulfide gasoline is discharged from the top of the tower, and all the bottom liquid (sulfur content <10µg.g -1 , nitrogen content <2µg.g -1 ) After being heated and pressurized, it enters the second-stage supplementary refining reactor; the supplementary refined product undergoes gas-liquid separation and fractionation to obtain various products.

[0043] Comparative Example 1 uses the same raw materials and the same catalyst as in Example 1. The process conditions and tests are shown in Table 3-4.

[0044] Comparative Example 2

[0045] Comparative Example 2 adopts the Shell process ("Research on the Application of High-Pressure Hydrogen Stripping in the Production Process of Fully Hydrogenated Lubricant Oil", Xue Nan, "Petroleum Refining and Chemical Industry", October 2019).

[0046] Comparative Example 2 uses the same raw materials and catalyst as in Example 1, and the process is that the hydroprocessing-hydrodecondensation product directly enters the supplementary refining section after high-pressure stripping, the hot high-fraction gas phase enters the cold low-pressure separator, the cold low-fraction gas is returned to the reaction system as circulating hydrogen, and the cold low-fraction oil directly enters the subsequent fractionation system, and fractionation obtains various products. The process conditions and test results are shown in Table 3-4.

[0047] Table 3 Process conditions

[0048]

[0049] *, for fresh feed.

[0050] Table 4 Test results

[0051]

[0052] **, for fresh feed.

[0053] From the data in Table 3-4, it can be seen that, using cycloalkane vacuum distillate as raw material, the two-stage process of hydrotreatment-hydrodecondensation-high-pressure hydrogen stripping / supplementary refining can produce products of equivalent quality to the conventional two-stage process of hydrotreatment-hydrodecondensation / supplementary refining, while avoiding the energy consumption of all the processes of feed pressure increase-pressure reduction-pressure increase, temperature increase-temperature reduction-temperature increase in the conventional two-stage process, reducing the equipment footprint, and reducing the equipment energy consumption by about 12%. Comparative Example 2 uses the Shell process flow, although the energy consumption is lower, but because the aromatics in the cold low fraction oil are directly fed into the fractionation system without hydrogenation refining, the light and thermal stability of the entire line of products are unqualified.

Claims

1. A process for producing cycloalkyl rubber filler oil by hydrogenation, comprising the following contents: (1) After the cycloalkyl vacuum distillate is mixed with hydrogen, it enters the hydroprocessing reaction zone and sequentially contacts with a hydroprotection catalyst, a hydrofining catalyst and a hydromodification catalyst to carry out a hydrogenation reaction, wherein the hydromodification catalyst contains amorphous silica-alumina and a modified Y molecular sieve; (2) the hydrotreatment effluent obtained in step (1) enters the hydrodecompression reaction zone and contacts and reacts with a hydrodecompression catalyst; (3) The hydrodecondensate obtained in step (2) enters a high-pressure stripping tower from the top, and hydrogen is injected into the bottom of the tower as a stripping medium. After stripping, a bottom oil from which H2S and NH3 are removed and a top effluent containing H2S, NH3, hydrogen and part of light oil are obtained; (4) The top effluent obtained in step (3) containing H2S, NH3, hydrogen and part of the light oil enters a cold high-pressure separator after heat exchange, and the cold high-fraction oil containing H2S and NH3 enters a cold low-fraction to separate the low-fraction gas, and then the cold low-fraction oil enters a H2S removal stripping tower to remove H2S and NH3, and enters a supplementary refining reaction zone after pressure increase and heat exchange; (5) The high-pressure stripping tower bottom oil obtained in step (3) is mixed with hydrogen and then enters the supplementary refining reaction zone together with the cold low-fraction oil from which H2S and NH3 are removed to perform a deep dearomatization reaction; (6) The reaction effluent obtained in step (5) enters a separation system to obtain a cycloalkane specialty oil product having a pour point that meets the requirements and good stability and a series of light white oils that meet the technical index requirements of light white oil (II) in NB / SH / T 0913-2015; in, The stripping pressure of the high-pressure stripping tower in step (3) is the same as the pressure in the hydrocondensation reaction zone. The reaction pressure in the hydrocondensation reaction zone is 5.0 to 18.0 MPa in terms of hydrogen partial pressure: The cycloalkyl specialty oil obtained in step (6) includes one or more of a series of rubber filler oils.

2. The process according to claim 1, characterized in that: A ZnO bed is arranged at the lower part of the packing area in the high-pressure stripping tower.

3. The process according to claim 1, characterized in that: The stripping temperature of the high-pressure stripping tower is 150-400°C, and the hydrogen consumption is higher than the chemical hydrogen consumption of hydrotreating and hydrodecondensation reaction.

4. The process according to claim 1, characterized in that: The cold high-fraction gas phase obtained in step (4) is selectively de-H2Sed and then re-enters the hydroprocessing reaction zone as circulating hydrogen.

5. The process according to claim 1, characterized in that: The cycloalkane vacuum distillate oil has an aromatic content of 30 to 99 wt % and a density of 0.923 to 0.955 g / cm 3 .

6. The process according to claim 1, characterized in that: The initial distillation point of the cycloalkyl vacuum distillate oil is 140-350°C, and the final distillation point is 400-600°C.

7. The process according to claim 1, characterized in that: Based on the weight of the catalyst, the hydrogenation and reforming catalyst contains 20wt% to 60wt% of amorphous silicon aluminum, 5wt% to 25wt% of modified Y molecular sieve, 10wt% to 30wt% of Group VIB metal calculated as oxide, and 4wt% to 15wt% of Group VIII metal calculated as oxide.

8. The process according to claim 7, characterized in that: The specific surface area of ​​the hydrogenation catalyst is 220 to 300 m 2 / g, the pore volume is 0.3-0.6mL / g, the pore volume with pore diameter of 3-10nm accounts for 75%-95% of the total pore volume, and the infrared acidity is 0.30-0.5mmol / g.

9. The process according to claim 1, characterized in that: The hydrodecondensation catalyst contains ZSM-5 molecular sieve, and based on the weight of the catalyst, the content of ZSM-5 molecular sieve is 50wt% to 85wt%, NiO and / or CoO is 1.0wt% to 8.0wt%, and the rest is a binder.

10. The process according to claim 1, characterized in that: The supplementary refining catalyst loaded in the supplementary refining reaction zone is a reducing hydrogenation refining catalyst, whose active metal is one or both of Pt and Pd, or nickel, and the catalyst carrier is Al2O3 or Al2O3-SiO2, selectively containing one or more of P, Ti, B, and Zr as an auxiliary agent.

11. The process according to claim 1, characterized in that: The operating conditions of the hydroprocessing reaction zone are: hydrogen partial pressure 5.0-18.0 MPa, reaction temperature 230-430°C, hydrogen-to-oil volume ratio 200-1500, volume space velocity 0.1-10.0 h -1 .

12. The process according to claim 11, characterized in that: The operating conditions of the hydroprocessing reaction zone are: hydrogen partial pressure 10.0-16.0 MPa, reaction temperature 350°C-410°C, hydrogen-oil volume ratio 600:1-1000:1, volume space velocity 0.3 h -1 ~0.5h -1 .

13. The process according to claim 1, characterized in that: The loading ratio of the hydrotreating catalyst to the hydrorefining catalyst in the hydrotreating reaction zone is 1:9~9:

1.

14. The process according to claim 1, characterized in that: The operating conditions of the hydrodecondensation reaction zone are: reaction temperature 230-430°C, hydrogen-to-oil volume ratio 200-1500, volume space velocity 0.1-10.0h -1 .

15. The process according to claim 14, characterized in that: The operating conditions of the hydrodecondensation reaction zone are: hydrogen partial pressure 10.0-16.0 MPa, reaction temperature 300°C-410°C, hydrogen-oil volume ratio 500:1-1000:1, volume space velocity 0.3 h -1 ~1.0h -1 .

16. The process according to claim 1, characterized in that: The reaction conditions of the supplementary refining reaction zone are: reaction temperature of 200°C to 300°C, hydrogen partial pressure of 6.0MPa to 18.0MPa, volume space velocity of 0.2h -1 ~3.0h -1 , hydrogen-oil volume ratio 400:1~1500:

1.

17. The process according to claim 16, characterized in that: The reaction conditions of the supplementary refining reaction zone are: reaction temperature of 210°C to 280°C, hydrogen partial pressure of 10.0 to 15.0 MPa, volume space velocity of 0.3 h -1 ~0.6h -1 , hydrogen-oil volume ratio 600:1~800:

1.

18. The process according to claim 1, characterized in that: The cycloalkyl specialty oil obtained in step (6) also includes transformer oil and / or refrigeration oil.

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