High-purity insulating oil prepared by deep processing of coal diesel oil and preparation method and application thereof
By deeply processing coal and diesel oil, including vacuum distillation, hydrogenation, and adsorption processes, high-purity insulating oil is prepared, and appropriate additives are added, which solves the problem of insufficient performance of existing coolants and realizes the preparation of high-performance coolants.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-30
- Publication Date
- 2026-04-03
AI Technical Summary
Existing coolants have defects such as poor dielectric properties, low thermal oxidation stability, and poor low-temperature fluidity, making it difficult to meet the high requirements of modern industry.
High-purity insulating oil is prepared through deep processing of coal and diesel oil, including vacuum distillation, hydrogenation, and adsorption processes. Antioxidants, solubilizers, defoamers, and stabilizers are added to form a high-performance coolant.
The prepared high-purity insulating oil has excellent dielectric properties, thermal stability and low-temperature fluidity, and meets the various performance indicators of lubricating oil. The raw materials are widely available and the preparation process is simple.
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Abstract
Description
Technical Field
[0001] This invention belongs to the field of coolant technology, specifically relating to a method for preparing high-purity insulating oil from kerosene and diesel oil through deep processing, as well as its application. Background Technology
[0002] Coolant is an indispensable medium in modern industrial production, widely used in power, metallurgy, chemical and other fields. With the continuous development of industrial technology, the performance requirements for coolants are also increasing, requiring excellent dielectric properties, thermal stability, low-temperature fluidity and other characteristics.
[0003] Traditional coolants are mainly made from mineral oil or synthetic oil as a base, with the addition of appropriate amounts of antioxidants, defoamers, and other additives. However, these coolants suffer from drawbacks such as poor dielectric properties, low thermal oxidation stability, and poor low-temperature fluidity, making it difficult to meet the high requirements of modern industry for coolants. To overcome these shortcomings, a series of new coolants have been developed, such as silicone oil and polymer coolants. However, while these new coolants offer improvements in some aspects, they often present new problems such as high cost and complex manufacturing processes.
[0004] Therefore, developing a novel dielectric coolant with excellent performance and simple preparation process has become an important issue that urgently needs to be addressed. Summary of the Invention
[0005] In view of this, the technical problem to be solved by the present invention is to provide a method for preparing high-purity insulating oil by deep processing of kerosene and diesel oil, as well as its application. The method for preparing high-purity insulating oil provided by the present invention is simple and has good performance when applied to coolant.
[0006] This invention provides a method for preparing high-purity insulating oil through deep processing of kerosene and diesel oil, comprising the following steps:
[0007] A) Distill kerosene under reduced pressure to separate components at 350-400℃;
[0008] B) The 350-400℃ component is hydrogenated and then adsorbed to obtain a high-purity insulating oil.
[0009] Preferably, the kerosene diesel oil contains >99% saturated hydrocarbons, <1% aromatic hydrocarbons, <0.5% sulfur, <0.5% nitrogen, and <50mgBr / 100g bromine index.
[0010] The initial boiling point of the kerosene is 115℃, and the final boiling point is 410℃.
[0011] Preferably, the pressure of the vacuum distillation is 1333 Pa, and the reflux ratio is 20:4 to 20:1.
[0012] Preferably, in the 350-400℃ component, the saturated hydrocarbon content is >99.5%, the aromatic hydrocarbon content is <0.3%, the sulfur content is less than 0.3%, the nitrogen content is <0.2%, and the bromine index is <30mgBr / 100g.
[0013] Preferably, the hydrogenation is carried out in the presence of a catalyst, which is selected from the Co / Mo series catalysts;
[0014] The hydrogenation reaction temperature is 300-400℃, the hydrogen pressure is 8-13MPa, the hydrogen-to-oil volume ratio is 500-1500, and the material space velocity is 0.5-2h. -1 .
[0015] Preferably, the hydrogenated product has an aromatic content of <0.01%, a sulfur content of <10ppm, a nitrogen content of <20ppm, and a bromine index of <15mgBr / 100g.
[0016] Preferably, the adsorption is performed using an adsorbent, which is selected from at least one of kaolin, activated carbon, and molecular sieve.
[0017] The adsorption temperature is 150-190℃, the pressure is 0.2-0.5MPa, and the space velocity is 1-3h. -1 .
[0018] The present invention also provides a high-purity insulating oil prepared by the above method.
[0019] The present invention also provides a coolant, comprising, by weight percentage:
[0020] 0.3%~0.5% antioxidants;
[0021] 10%~20% solubility accelerator;
[0022] 0.05%~0.2% defoamer;
[0023] 2%~5% stabilizer;
[0024] The remaining amount of the above-mentioned high-purity insulating oil.
[0025] Preferably, the antioxidant is a mixture of alkyl diphenol and alkyl diphenylamine in a 1:1 ratio;
[0026] The solubility promoter is selected from saturated polyol esters;
[0027] The defoamer is methyl silicone oil or ethyl silicone oil;
[0028] The stabilizer is either silicon dioxide or titanium dioxide.
[0029] Compared with existing technologies, this invention provides a method for preparing high-purity insulating oil through deep processing of kerosene, comprising the following steps: A) subjecting kerosene to vacuum distillation to separate the 350-400℃ component; B) hydrogenating the 350-400℃ component and then subjecting it to adsorption with clay to obtain high-purity insulating oil. This invention optimizes process conditions such as distillation, hydrogenation, and adsorption to fully remove aromatics and other impurities from the kerosene feedstock, improving the product's refining degree and ensuring that the product is sulfur-free, nitrogen-free, and aromatic-free, resulting in better environmental friendliness. Furthermore, the preparation method is simple. Additives are added to the high-purity insulating oil to ensure that the coolant meets the performance requirements of lubricating oil. Detailed Implementation
[0030] This invention provides a method for preparing high-purity insulating oil through deep processing of kerosene and diesel oil, comprising the following steps:
[0031] A) Distill kerosene under reduced pressure to separate components at 350-400℃;
[0032] B) The 350-400℃ component is hydrogenated and then adsorbed with clay to obtain high-purity insulating oil.
[0033] This invention uses kerosene as a raw material to prepare high-purity insulating oil. The kerosene contains >99% saturated hydrocarbons, <1% aromatic hydrocarbons, <0.5% sulfur, <0.5% nitrogen, and <50mgBr / 100g bromine index. The initial boiling point of the kerosene is 115℃, and the final boiling point is 410℃.
[0034] This invention makes full use of unconventional resources such as coal and diesel oil, providing a new development path for the lubricating oil industry and yielding good economic and social benefits.
[0035] The present invention pre-treats kerosene, the pre-treatment including removing impurities and moisture, to obtain pre-treated kerosene.
[0036] Then, the pretreated kerosene is subjected to vacuum distillation to separate the 350-400℃ components.
[0037] The pressure of the vacuum distillation is 1333 Pa, and the reflux ratio is 20:4 to 20:1, which can be any value between 20:4, 20:3, 20:2, 20:1, or 20:4 to 20:1.
[0038] In the 350-400℃ component, the saturated hydrocarbon content is >99.5%, the aromatic hydrocarbon content is <0.3%, the sulfur content is less than 0.3%, the nitrogen content is <0.2%, and the bromine index is <30mgBr / 100g.
[0039] Next, the component at 350-400°C is hydrogenated, wherein the hydrogenation is carried out in the presence of a catalyst selected from the Co / Mo series catalysts, preferably Co-Mo type K-757 (STARS technology) or Nebula-20 (Nebula technology); the present invention improves the efficiency of hydrogenation reaction and increases product yield by optimizing the selection of catalyst and the conditions of use.
[0040] The hydrogenation reaction temperature is 300-400℃, which can be 300, 320, 340, 350, 360, 380, 400℃, or any value between 300-400℃; the hydrogen pressure is 8-13 MPa, which can be 8, 9, 10, 11, 12, 13 MPa, or any value between 8-13 MPa; the hydrogen-to-oil volume ratio is 500-1500, which can be 500, 600, 700, 800, 900, 1000, 1100, 1200, 1300, 1400, 1500, or any value between 500-1500; and the material space velocity is 0.5-2 h⁻¹. -1 It can be 0.5, 1, 1.5, 2, or 0.5-2h. -1 Any value between.
[0041] The hydrogenated product contains <0.01% aromatics, <10ppm sulfur, <20ppm nitrogen, and <15mgBr / 100g bromine index.
[0042] Next, the hydrogenated product is adsorbed. In this invention, the adsorption is carried out using an adsorbent selected from at least one of clay, activated carbon, and molecular sieve, preferably clay.
[0043] The adsorption temperature is 150-190℃, which can be any value between 150, 160, 170, 180, 190℃, or 150-190℃; the pressure is 0.2-0.5MPa, which can be any value between 0.2, 0.3, 0.4, 0.5MPa, or 0.2-0.5MPa; and the space velocity is 1-3h. -1 It can be 1, 2, 3, or 1-3h -1 Any value between.
[0044] After adsorption is complete, a high-purity insulating oil is obtained, wherein the bromine index of the high-purity insulating oil is <1 mgBr / 100g.
[0045] The present invention also provides a high-purity insulating oil prepared by the above method. In the present invention, the high-purity insulating oil can be used directly as a coolant; however, to improve performance parameters, additives can be added to the high-purity insulating oil.
[0046] The present invention also provides a coolant, comprising, by weight percentage:
[0047] 0.3%~0.5% antioxidants;
[0048] 10%~20% solubility accelerator;
[0049] 0.05%~0.2% defoamer;
[0050] 2%~5% stabilizer;
[0051] The remaining amount of the above-mentioned high-purity insulating oil.
[0052] The coolant provided by this invention includes 0.3% to 0.5% of an antioxidant, which can be any value between 0.3%, 0.35%, 0.4%, 0.45%, 0.5%, or 0.3% to 0.5%. The antioxidant is a mixture of alkyl diphenol and alkyl diphenylamine in a 1:1 ratio.
[0053] The coolant provided by this invention further includes 10% to 20% of a dissolution promoter, which can be any value between 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, or 10% to 20%. The dissolution promoter is selected from saturated polyol esters, and the saturated polyol ester is selected from at least one of pentaerythritol polyol ester and neopentyl polyol ester.
[0054] The coolant provided by this invention further includes 0.05% to 0.2% of an antifoaming agent, which can be any value between 0.05%, 0.1%, 0.15%, 0.2%, or 0.05% to 0.2%. The antifoaming agent is methyl silicone oil or ethyl silicone oil.
[0055] The coolant provided by this invention further includes 2% to 5% of a stabilizer, which can be 2%, 3%, 4%, 5%, or any value between 2% and 5%. The stabilizer is either silicon dioxide or titanium dioxide.
[0056] This invention rationally selects and proportions the types and amounts of additives, such as antioxidants, defoamers, and stabilizers, to ensure that the product meets the various performance requirements of lubricating oils, such as viscosity, flash point, pour point, and thermal conductivity.
[0057] This invention provides a high-purity insulating oil prepared from coal as raw material through processes such as distillation, hydrogenation, and adsorption. When used as a dielectric coolant, it not only has excellent dielectric properties, thermal stability, and low-temperature fluidity, but also has a wide range of raw material sources and a simple preparation process, showing good application prospects.
[0058] To further understand the present invention, the following embodiments illustrate the preparation of high-purity insulating oil from deep processing of kerosene and diesel oil, the preparation method thereof, and its application. The scope of protection of the present invention is not limited by the following embodiments.
[0059] In the following examples, the kerosene used has a saturated hydrocarbon content >99%, an aromatic hydrocarbon content <1%, a sulfur content <0.5%, a nitrogen content <0.5%, and a bromine index <50mgBr / 100g; the initial boiling point of the kerosene is 115℃ and the final boiling point is 410℃.
[0060] The Co / Mo catalyst is Co-Mo type K-757 (STARS technology).
[0061] Example 1:
[0062] A method for synthesizing a high-purity insulating synthetic oil includes the following steps:
[0063] Steps: Pre-treat the kerosene to remove impurities and moisture; transfer the pre-treated kerosene to a distillation column and distill it at 1333 Pa and a reflux ratio of 20:4; collect the fraction from the distillation column at 350-400℃ and determine its composition. The saturated hydrocarbon content should be >99.5%, the aromatic hydrocarbon content <0.3%, the sulfur content <0.3%, the nitrogen content <0.2%, and the bromine index <30 mgBr / 100g. The distilled product can be used directly.
[0064] Example 2:
[0065] A method for synthesizing a high-purity insulating synthetic oil includes the following steps:
[0066] Step 1: After pretreatment, the coal diesel oil is sent to a distillation column and distilled at 1333 Pa and a reflux ratio of 20:4. The fraction at 350-400℃ is collected and its composition is determined to be: saturated hydrocarbon content >99.5%, aromatic hydrocarbon content <0.3%, sulfur content <0.3%, nitrogen content <0.2%, and bromine index <30mgBr / 100g.
[0067] Step 2: The 350-400℃ fraction obtained in Step 1 is hydrogenated using a fresh Co / Mo catalyst. The sample is then fed into a fixed-bed hydrogenation reactor and subjected to hydrogenation at a temperature of 400℃, a hydrogen pressure of 12 MPa, a hydrogen-to-oil volume ratio of 800, and a material space velocity of 1 h⁻¹. -1 Under certain conditions, a hydrogenation reaction was carried out, the reaction products were collected, and their composition and impurity content were determined.
[0068] Step 3: Determine whether the hydrogenated sample meets the following conditions: aromatic content < 0.01%, sulfur content < 10 ppm, nitrogen content < 20 ppm, bromine index < 15 mgBr / 100g. If it meets the conditions, proceed with the trial. If it does not meet the conditions, proceed to Step 2 until the indicators are met.
[0069] Example 3:
[0070] A method for synthesizing a high-purity insulating synthetic oil includes the following steps:
[0071] Step 1: After pretreatment, the coal diesel oil is sent to a distillation column and distilled at 1333 Pa and a reflux ratio of 20:4. The fraction at 350-400℃ is collected and its composition is determined to be: saturated hydrocarbon content >99.5%, aromatic hydrocarbon content <0.3%, sulfur content <0.3%, nitrogen content <0.2%, and bromine index <30mgBr / 100g.
[0072] Step 2: The 350-400℃ fraction obtained in Step 1 is hydrogenated using a fresh Co / Mo catalyst. The sample is then fed into a fixed-bed hydrogenation reactor and subjected to hydrogenation at a temperature of 400℃, a hydrogen pressure of 12 MPa, a hydrogen-to-oil volume ratio of 800, and a material space velocity of 1 h⁻¹. -1 Under certain conditions, a hydrogenation reaction was carried out, the reaction products were collected, and their composition and impurity content were determined.
[0073] Step 3: Determine whether the sample after hydrogenation meets the following conditions: aromatic content < 0.01%, sulfur content < 10 ppm, nitrogen content < 20 ppm, bromine index < 15 mgBr / 100g. If it meets the conditions, proceed with the trial; if it does not, proceed with step 2 for cyclic hydrogenation.
[0074] Step 4: The hydrogenated product is subjected to adsorption with bleaching clay at an adsorption temperature of 170℃, a pressure of 0.2MPa, and a space velocity of 2h. -1 Adsorption was performed under specific conditions, and the adsorbed product was collected. Its bromine index was determined to be less than 1 mgBr / 100g. The hydrogenated and adsorbed product was then used directly.
[0075] Example 4:
[0076] A method for synthesizing a high-purity insulating synthetic oil includes the following steps:
[0077] Step 1: After pretreatment, the coal diesel oil is sent to a distillation column and distilled at 1333 Pa and a reflux ratio of 20:4. The fraction at 350-400℃ is collected and its composition is determined to be: saturated hydrocarbon content >99.5%, aromatic hydrocarbon content <0.3%, sulfur content <0.3%, nitrogen content <0.2%, and bromine index <30mgBr / 100g.
[0078] Step 2: The 350-400℃ fraction obtained in Step 1 is hydrogenated using a fresh Co / Mo catalyst. The sample is then fed into a fixed-bed hydrogenation reactor and subjected to hydrogenation at a temperature of 400℃, a hydrogen pressure of 12 MPa, a hydrogen-to-oil volume ratio of 800, and a material space velocity of 1 h⁻¹. -1 Under certain conditions, a hydrogenation reaction was carried out, the reaction products were collected, and their composition and impurity content were determined.
[0079] Step 3: Determine whether the sample after hydrogenation meets the following conditions: aromatic content < 0.01%, sulfur content < 10 ppm, nitrogen content < 20 ppm, bromine index < 15 mgBr / 100g. If it meets the conditions, proceed with the trial; if it does not, proceed with step 2 for cyclic hydrogenation.
[0080] Step 4: The hydrogenated product is subjected to adsorption with bleaching clay at an adsorption temperature of 170℃, a pressure of 0.2MPa, and a space velocity of 2h. -1 Adsorption was carried out under certain conditions, the adsorbed product was collected, and its bromine index was determined to be less than 1 mgBr / 100g.
[0081] Step 5: For samples with a bromine index less than 1 mgBr / 100g obtained in Step 4, the addition amount is 86.4%; 2,6-di-tert-butyl-p-cresol and octylbutyldiphenylamine are added as antioxidants in a 1:1 mass ratio, with an addition amount of 0.5%; pentaerythritol ester is added to increase the solubility of the additives, with an addition amount of 10%; methyl silicone oil is added as an antifoaming agent, with an addition amount of 0.1%; and silica is added as a stabilizer, with an addition amount of 3%.
[0082] Test case
[0083] The four samples in Examples 1-4 were tested for their respective indicators, and the results are shown in Table 1.
[0084] The test methods are as follows: kinematic viscosity (GB / T 265), flash point (open cup) (GB / T3536), pour point (GB / T 3535), specific heat capacity (differential scanning calorimetry), thermal conductivity (hot wire method HW), dielectric constant (IEC 60247), and density (GB / T 29617-2013).
[0085] Table 1
[0086]
[0087] As can be seen from the test results in Table 1, the products prepared in Examples 3 and 4 both meet the index requirements and are qualified as coolant indicators. The product prepared in Example 4 has even better performance.
[0088] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.
Claims
1. A method for preparing high-purity insulating oil through deep processing of kerosene and diesel oil, characterized in that, Includes the following steps: A) Perform vacuum distillation on kerosene to separate components at 350-400℃; B) The 350-400℃ component is hydrogenated and then adsorbed to obtain high-purity insulating oil.
2. The method according to claim 1, characterized in that, The kerosene diesel oil contains >99% saturated hydrocarbons, <1% aromatic hydrocarbons, <0.5% sulfur, <0.5% nitrogen, and <50mgBr / 100g bromine index. The initial boiling point of the kerosene is 115℃, and the final boiling point is 410℃.
3. The method according to claim 1, characterized in that, The pressure of the vacuum distillation is 1333 Pa, and the reflux ratio is 20:4 to 20:
1.
4. The method according to claim 1, characterized in that, In the 350-400℃ component, the saturated hydrocarbon content is >99.5%, the aromatic hydrocarbon content is <0.3%, the sulfur content is less than 0.3%, the nitrogen content is <0.2%, and the bromine index is <30mgBr / 100g.
5. The method according to claim 1, characterized in that, The hydrogenation is carried out in the presence of a catalyst, which is selected from the Co / Mo series catalysts. The hydrogenation reaction temperature is 300-400℃, the hydrogen pressure is 8-13MPa, the hydrogen-to-oil volume ratio is 500-1500, and the material space velocity is 0.5-2h. -1 .
6. The method according to claim 1, characterized in that, The hydrogenated product contains <0.01% aromatics, <10ppm sulfur, <20ppm nitrogen, and <15mgBr / 100g bromine index.
7. The method according to claim 1, characterized in that, The adsorption is carried out by an adsorbent, which is selected from at least one of kaolin, activated carbon, and molecular sieve. The adsorption temperature is 150-190℃, the pressure is 0.2-0.5MPa, and the space velocity is 1-3h. -1 .
8. A high-purity insulating oil prepared by the method according to any one of claims 1 to 7.
9. A coolant, characterized in that, By weight percentage, including: 0.3%~0.5% antioxidants; 10%~20% solubility accelerator; 0.05%~0.2% defoamer; 2%~5% stabilizer; The remaining amount is the high-purity insulating oil as described in claim 8.
10. The coolant according to claim 9, characterized in that, The antioxidant is a mixture of alkyl diphenol and alkyl diphenylamine in a 1:1 ratio; The solubility promoter is selected from saturated polyol esters; The defoamer is methyl silicone oil or ethyl silicone oil; The stabilizer is either silicon dioxide or titanium dioxide.