WO2007081088A1 - Heavy aromatic electrical insulation oil with high breakdown voltage - Google Patents

Heavy aromatic electrical insulation oil with high breakdown voltage Download PDF

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Publication number
WO2007081088A1
WO2007081088A1 PCT/KR2006/005113 KR2006005113W WO2007081088A1 WO 2007081088 A1 WO2007081088 A1 WO 2007081088A1 KR 2006005113 W KR2006005113 W KR 2006005113W WO 2007081088 A1 WO2007081088 A1 WO 2007081088A1
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Prior art keywords
electrical insulating
insulating oil
aromatics
oil composition
aromatic
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Application number
PCT/KR2006/005113
Other languages
French (fr)
Inventor
Jae Suk Koh
Seung Gweon Hong
Tae Wook Kwon
Original Assignee
Sk Energy Co., Ltd.
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Application filed by Sk Energy Co., Ltd. filed Critical Sk Energy Co., Ltd.
Priority to CN2006800505156A priority Critical patent/CN101356590B/en
Publication of WO2007081088A1 publication Critical patent/WO2007081088A1/en

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Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B3/00—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties
    • H01B3/18—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties mainly consisting of organic substances
    • H01B3/20—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties mainly consisting of organic substances liquids, e.g. oils
    • H01B3/22—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties mainly consisting of organic substances liquids, e.g. oils hydrocarbons
    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10G—CRACKING HYDROCARBON OILS; PRODUCTION OF LIQUID HYDROCARBON MIXTURES, e.g. BY DESTRUCTIVE HYDROGENATION, OLIGOMERISATION, POLYMERISATION; RECOVERY OF HYDROCARBON OILS FROM OIL-SHALE, OIL-SAND, OR GASES; REFINING MIXTURES MAINLY CONSISTING OF HYDROCARBONS; REFORMING OF NAPHTHA; MINERAL WAXES
    • C10G35/00—Reforming naphtha
    • C10G35/04—Catalytic reforming
    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10G—CRACKING HYDROCARBON OILS; PRODUCTION OF LIQUID HYDROCARBON MIXTURES, e.g. BY DESTRUCTIVE HYDROGENATION, OLIGOMERISATION, POLYMERISATION; RECOVERY OF HYDROCARBON OILS FROM OIL-SHALE, OIL-SAND, OR GASES; REFINING MIXTURES MAINLY CONSISTING OF HYDROCARBONS; REFORMING OF NAPHTHA; MINERAL WAXES
    • C10G7/00—Distillation of hydrocarbon oils
    • C10G7/08—Azeotropic or extractive distillation

Definitions

  • the present invention relates to a high- voltage- withstand electrical insulating oil composition comprising a high-boiling-point aromatic fraction. More particularly, the present invention relates to a high-voltage-withstand electrical insulating oil composition having high stability, excellent low-temperature fluidity and a high dielectric breakdown voltage, which comprises a component having a specific distillation range, separated by distillation from a mixed fraction of aromatic hydrocarbons produced in a process of converting a hydrocarbon mixture into an aromatic fraction in the presence of a metal catalyst.
  • Electrical insulation oils for film condensers which have been developed and used in the prior art, include polychlorinated bisphenyl-based oil, which was widely used, but the production of which was stopped due to very low biodegradability, and various kinds of aromatic hydrocarbon-based and phosphate-based insulating oils, which were developed in order to substitute for the polychlorinated bisphenyl (PCB)-based oil.
  • PCB polychlorinated bisphenyl
  • the aromatic hydrocarbon-based oils which have a relatively low electrical insulating property and dielectric loss, have mainly been used.
  • Most of these aromatic hydrocarbon-based insulating oils are based on an aromatic component having 14-22 carbon atoms.
  • the aromatic insulating oils have not only excellent voltage-withstand capability, but also an excellent ability to absorb hydrogen gas, generated when high voltage is applied, such that partial electric discharge does not lead to dielectric breakdown.
  • these aromatic hydrocarbon-based insulating oils have been used in film condensers to which high voltage is applied.
  • aromatic electrical insulating oils examples include phenyl xylyl ethanes (hereinafter, referred to as PXE), benzyl toluenes, dibenzyl toluenes, ethyl biphenyls, ethyl diphenyl ethanes, and alkylbenzenes, and these oils have been used alone or in a mixture of two or more thereof.
  • the aromatic hydrocarbon-based electrical insulating oils are synthesized by alkylation or transalkylation and are produced mainly as single component or as mixtures of about 10 isomers. Such synthetic aromatic hydrocarbon-based insulating oils should maintain a specific composition in order to show their properties.
  • ethyl biphenyls show a great difference in their low-temperature fluidity depending on the composition of isomers, and thus require an operation of controlling composition by mixing more than two different components with each other.
  • each of an ethylene/biphenyl mixture 10 and a propylene/biphenyl mixture 20 is alkylated or transalkylated through an alkylation reactor and then passed through a multistage distillation column 40 to separate and synthesize a component having a desired distillation range.
  • the synthesized components are mixed with each other in a mixing unit 50 for controlling composition.
  • this operation has shortcomings in that it is complex and incurs increased production cost, because the mixing process for controlling properties must additionally be carried out after the synthesis process.
  • alkylbenzene is synthesized in a simple one-step process by alkylating benzene with a C 12-16 alpha-olefin in the presence of a catalyst to produce a mixture having a very complex composition.
  • the alkylbenzene thus synthesized has low fluidity at low temperatures, and a low ability to absorb hydrogen gas, and thus is difficult to use for the impregnation of film condensers to which high voltage is applied.
  • the present invention aims to provide an electrical insulating composition comprising aromatic hydrocarbons, which eliminates the above-described troublesome process of mixing specific components with each other after the synthesis thereof to control the physical properties of a composition, improves the low-temperature fluidity of the prior aromatic hydrocarbon mixture and, at the same time, has excellent voltage withstand capability and an excellent capability to absorb hydrogen gas.
  • the present invention is based on aromatic hydrocarbon in order to increase the ability of electrical insulating oil to absorb hydrogen gas.
  • the present invention has been completed based on the use of a mixed fraction of aromatic hydrocarbons produced in a platforming or aromatizing process of converting an aliphatic mixture into aromatics in the presence of a metal catalyst such as a platinum catalyst or nickel catalyst for economical production.
  • aromatic hydrocarbon has excellent capability to absorb hydrogen gas compared to paraffinic hydrocarbon, but the hydrogen absorption property thereof varies greatly depending on the structure, length and number of alkyl groups substituted in the aromatic rings, and on the kind of aromatics, i.e., the number and linking form of the aromatic rings.
  • the present invention has been made in order to solve this problem, and it is an object of the present invention to provide an electrical insulating oil composition comprising monocyclic, dicyclic and tricyclic aromatic hydrocarbons at a specific ratio through the use only of a fraction having a specific distillation range, separated by distillation from a mixed fraction of aromatic hydrocarbons produced in a platforming or aromatizing process.
  • an electrical insulating oil composition comprising a component having a distillation range of 280-330 " C, obtained by distilling a mixed fraction of aromatic hydrocarbons produced in a platforming or aromatizing process.
  • an electrical insulating oil composition which has a content of aromatic hydrocarbons of 95-100 area percent, as analyzed by HPLC, and has an area ratio of 3-20: 60-94: 3-20 of monocyclic (one-ring) aromatics: bicyclic (two-ring) aromatics: tricyclic (three-ring) aromatics, as analyzed by HPLC, when the aromatic hydrocarbons are classified according to the number of rings into monocyclic aromatics, bicyclic aromatics and tricyclic aromatics.
  • an electrical insulating oil composition which is obtained by distilling a mixed fraction of aromatic hydrocarbons produced in a platforming or aromatizing process and has a viscosity of 4.8-7.1 cSt at 40 ° C, a dielectric breakdown voltage of 70-10O kV, and a pour point of less than -40 ° C.
  • said electrical insulating oil composition further comprise at least a compound selected from the group consisting of phenyl xylyl ethanes, benzyl toluenes, dibenzyl toluenes, ethyl biphenyls, ethyl diphenyl ethanes and alkylbenzenes.
  • a high-voltage-withstand electrical insulating oil composition having high stability, excellent low-temperature fluidity and high dielectric breakdown voltage can be obtained by using only a fraction having a specific distillation range, which is separated by distillation from a mixed fraction of aromatic hydrocarbons produced in a process of converting a hydrocarbon mixture into aromatics in the presence of a metal catalyst.
  • the electrical insulating oil composition according to the present invention may further comprise other electrical insulating oil components, which are conventionally used.
  • the component having the above-specified distillation range consists of monocyclic, bicyclic and tricyclic aromatic hydrocarbons at a specific ratio, and thus is advantageous in that it has high dielectric breakdown voltage and, when impregnated into a film condenser, can significantly increase the potential gradient of the condenser.
  • FIG. 1 is a process diagram schematically showing one embodiment of a process for preparing electrical insulating oil for film condensers according to the prior art.
  • FIG. 2 is a process diagram schematically showing one embodiment of a process for preparing electrical insulating oil for film condensers according to the present invention.
  • FIG. 3 is a graphic diagram showing the comparison of viscosity properties between electrical insulating oils according to Example 1 and Comparative Example 1.
  • FIG. 4 is a graphic diagram showing the comparison of dielectric breakdown voltage properties between electrical insulating oils according to Example 1 and Comparative Example 1.
  • 10 ethylene, biphenyl; 20: propylene, biphenyl; 30: alkylation reactor; 40: distillation column; 50: mixing unit 100: raw material feeding unit; 200: isomerization reactor 300: distillation column [Best Mode]
  • the aromatic hydrocarbon-based electrical insulating oil according to the prior invention is obtained as a product resulting from alkylation or transalkylation, and must be subjected to a mixing process for controlling composition after the synthesis process thereof.
  • an aromatic fraction converted from a hydrocarbon mixture in the presence of a metal catalyst such as platinum or nickel catalyst is used as a raw material fraction.
  • This fraction has various aromatic hydrocarbon components, and thus it is difficult to analyze all the components.
  • a scientific and reasonable standard for analyzing the composition of this fraction is needed, and thus, it is required to obtain a fraction having a specific composition.
  • the distillation range of a mixed fraction of aromatic hydrocarbons produced in a platforming or aromatizing process is controlled such that only an aromatic fraction comprising a composition having the desired specific properties can be obtained.
  • this aromatic fraction is separated by HPLC into monocyclic aromatics, bicyclic aromatics and tricyclic aromatics and then analyzed, and on the basis of the analysis results, an electrical insulating oil composition having the desired properties is obtained.
  • the kind of aromatic hydrocarbon determines the stability and fluidity of electrical insulating oil as well as the quantity of evaporation of volatile organic compounds, and thus the control of the composition thereof is very important.
  • a fraction having a distillation range of 280-330 ° C is separated by distillation from a mixed fraction of aromatic hydrocarbons produced in a platforming or aromatizing process, and it preferably has an aromatic hydrocarbon content of 95-100 area percent as analyzed by HPLC, and the area percent ratio of monocyclic aromatics: bicyclic aromatics: tricyclic aromatics in the hydrocarbon fraction is 3-20: 60-94: 3-20 as analyzed by HPLC.
  • the content of the monocyclic aromatics in the aromatic hydrocarbon fraction having said composition is too high, the nature of aliphatic hydrocarbon in the fraction will be increased, resulting in a decrease in the hydrogen gas-absorbing capability or low-temperature fluidity of the fraction.
  • the composition will have increased viscosity at a temperature higher than room temperature, and a strong odor.
  • the content of the tricyclic aromatics is higher than that of the above-specified composition, the amount of components that precipitate as crystals at low temperature will be increased, leading to a decrease in durability to partial electric discharge, and if it is lower than that of the above composition, the density of the oil composition will be decreased, leading to a decrease in voltage-withstand capability at a temperature higher than room temperature.
  • FIG. 2 schematically shows one preferred embodiment of a process for preparing electrical insulating oil according to the present invention.
  • a hydrocarbon mixture for example, naphtha is fed through a raw material feeding unit 100 into an isomerization reactor 200, in which it is converted into aromatics in the presence of a metal catalyst such as platinum or nickel. Then, the resulting aromatic fraction is fed into a distillation column 300, in which it is distilled in a vacuum to be within the distillation range of 280-330 0 C .
  • the distillation range deviates from the above range, the low-temperature fluidity or flash point of the insulating oil will be decreased, leading to a decrease in stability, and the odor intensity of the insulating oil will be increased, deteriorating the working environment.
  • the fraction having a distillation range of 280-330 ° C preferably has a viscosity of 4.8- 7.1 cSt at 40 then ⁇ O ° C .
  • the electrical insulating oil composition according to the present invention may further comprise at least one compound selected from the group consisting of components used as electrical insulating oils in the prior art, for example, phenyl xylyl ethane, benzyl toluene, dibenzyl toluene, ethyl biphenyl, ethyl diphenyl ethane, and alkyl benzene.
  • This component can be used in an amount of about 30-60 wt% based on the weight of the electrical insulating oil composition, but the present invention is not specifically limited thereto.
  • the electrical insulating oil of the present invention is used after removing water therefrom by a conventional method.
  • Conventional methods of removing water include vacuum spray degassing, thin film vacuum degassing, and molecular sieve methods, but the present invention is not specifically limited thereto.
  • the high-voltage-withstand electrical insulating oil having high stability, excellent low-temperature fluidity and high dielectric breakdown voltage can be obtained using a fraction having a specific distillation range, which is separated by distillation from a mixed fraction of aromatic hydrocarbons produced in a process of converting a hydrocarbon mixture into aromatics in the presence of a metal catalyst.
  • said fraction having a specific distillation range consists of monocyclic, bicyclic and tricyclic aromatic hydrocarbons at a specific ratio, and thus is advantageous in that it has high dielectric breakdown voltage and, when impregnated into a film condenser, can significantly increase the potential gradient of the condenser.
  • Naphtha as a raw material was converted into aromatics through a reforming process at a pressure of 3 kg/cm 2 and a temperature of 500 " C in the presence of a platinum catalyst, and then an aromatic fraction was separated from the aromatics through a liquid-liquid extraction process.
  • the separated aromatic fraction was continuously distilled using two distillation columns having a theoretical plate number of 60 to obtain a composition having a distillation range of 280-330 "C and an aromatic content of 99 area percent as analyzed by HPLC.
  • the composition was used as electrical insulating oil, and its physical properties and dielectric breakdown voltage are measured to show in Table 1 below as a measurement result. Also, the viscosity properties depending on change in temperature of the obtained electrical insulating oil are shown in FIG. 3, and the dielectric breakdown voltage properties thereof are shown in FIG. 4.
  • Example 2 A composition was obtained in the same manner as in Example 1, except that the distillation range was controlled to 290-330 ° C. The obtained composition was used as electrical insulating oil, and its physical properties and dielectric breakdown voltage are measured to show in Table 1 below as a measurement result.
  • Example 3 A composition was obtained in the same manner as in Example 1, except that the distillation range was controlled to 290-320 ° C. The obtained composition was used as electrical insulating oil, and its physical properties and dielectric breakdown voltage are measured to show in Table 1 below as a measurement result.
  • the electrical insulating oil according to the present invention has low viscosity even at low temperature, and high dielectric breakdown voltage, indicating excellent electrical insulating properties.

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Abstract

Disclosed herein is an electrical insulating oil composition using a high-boiling-point aromatic fraction. The oil composition comprises a component having a distillation range of 280-330 °C, obtained by continuously distilling an aromatic hydrocarbon fraction from a platforming or aromatizing process. According to the disclosed invention, an electrical insulating oil composition having excellent voltage-withstand capability and excellent gas absorption capability can be obtained from an aromatic fraction. Also, the electrical insulating oil contains no unstable components, resulting in an increase in electrical properties, and thus has advantages of high stability and high potential gradient.

Description

[DESCRIPTION]
[Invention Title]
HEAVY AROMATIC ELECTRICAL INSULATION OIL WITH HIGH BREAKDOWN VOLTAGE [Technical Field]
CROSS REFERENCE TO RELATED APPLICATION(S)
This application claims the benefit of Korean Patent Application No.10-2006-0003555, filed January 12, 2006, entitled "Heavy aromatic electrical insulation oil with high breakdown voltage." The present invention relates to a high- voltage- withstand electrical insulating oil composition comprising a high-boiling-point aromatic fraction. More particularly, the present invention relates to a high-voltage-withstand electrical insulating oil composition having high stability, excellent low-temperature fluidity and a high dielectric breakdown voltage, which comprises a component having a specific distillation range, separated by distillation from a mixed fraction of aromatic hydrocarbons produced in a process of converting a hydrocarbon mixture into an aromatic fraction in the presence of a metal catalyst. [Background Art]
Electrical insulation oils for film condensers, which have been developed and used in the prior art, include polychlorinated bisphenyl-based oil, which was widely used, but the production of which was stopped due to very low biodegradability, and various kinds of aromatic hydrocarbon-based and phosphate-based insulating oils, which were developed in order to substitute for the polychlorinated bisphenyl (PCB)-based oil. Among them, the aromatic hydrocarbon-based oils, which have a relatively low electrical insulating property and dielectric loss, have mainly been used. Most of these aromatic hydrocarbon-based insulating oils are based on an aromatic component having 14-22 carbon atoms. The aromatic insulating oils have not only excellent voltage-withstand capability, but also an excellent ability to absorb hydrogen gas, generated when high voltage is applied, such that partial electric discharge does not lead to dielectric breakdown. Thus, these aromatic hydrocarbon-based insulating oils have been used in film condensers to which high voltage is applied.
Examples of such aromatic electrical insulating oils include phenyl xylyl ethanes (hereinafter, referred to as PXE), benzyl toluenes, dibenzyl toluenes, ethyl biphenyls, ethyl diphenyl ethanes, and alkylbenzenes, and these oils have been used alone or in a mixture of two or more thereof. The aromatic hydrocarbon-based electrical insulating oils are synthesized by alkylation or transalkylation and are produced mainly as single component or as mixtures of about 10 isomers. Such synthetic aromatic hydrocarbon-based insulating oils should maintain a specific composition in order to show their properties. Particularly, ethyl biphenyls show a great difference in their low-temperature fluidity depending on the composition of isomers, and thus require an operation of controlling composition by mixing more than two different components with each other. For example, as shown in FIG. 1 , each of an ethylene/biphenyl mixture 10 and a propylene/biphenyl mixture 20 is alkylated or transalkylated through an alkylation reactor and then passed through a multistage distillation column 40 to separate and synthesize a component having a desired distillation range. The synthesized components are mixed with each other in a mixing unit 50 for controlling composition. However, this operation has shortcomings in that it is complex and incurs increased production cost, because the mixing process for controlling properties must additionally be carried out after the synthesis process.
Also, alkylbenzene is synthesized in a simple one-step process by alkylating benzene with a C12-16 alpha-olefin in the presence of a catalyst to produce a mixture having a very complex composition. However, the alkylbenzene thus synthesized has low fluidity at low temperatures, and a low ability to absorb hydrogen gas, and thus is difficult to use for the impregnation of film condensers to which high voltage is applied.
Accordingly, there has been a continued demand for electrical insulating oil, which is synthesized through a simple process and, at the same time, has good ability to withstand partial electric discharge at high voltage due to excellent low-temperature fluidity and an excellent ability to absorb hydrogen gas. Particularly, it is commercially preferable to develop an electrical insulating oil, which, when impregnated in a film condenser, can increase the potential gradient of the condenser to reduce the distance between the electrodes of the condenser, thus reducing the volume of the condenser. [Disclosure]
[Technical Problem]
Accordingly, the present invention aims to provide an electrical insulating composition comprising aromatic hydrocarbons, which eliminates the above-described troublesome process of mixing specific components with each other after the synthesis thereof to control the physical properties of a composition, improves the low-temperature fluidity of the prior aromatic hydrocarbon mixture and, at the same time, has excellent voltage withstand capability and an excellent capability to absorb hydrogen gas.
The present invention is based on aromatic hydrocarbon in order to increase the ability of electrical insulating oil to absorb hydrogen gas. hi particular, the present invention has been completed based on the use of a mixed fraction of aromatic hydrocarbons produced in a platforming or aromatizing process of converting an aliphatic mixture into aromatics in the presence of a metal catalyst such as a platinum catalyst or nickel catalyst for economical production.
Generally, aromatic hydrocarbon has excellent capability to absorb hydrogen gas compared to paraffinic hydrocarbon, but the hydrogen absorption property thereof varies greatly depending on the structure, length and number of alkyl groups substituted in the aromatic rings, and on the kind of aromatics, i.e., the number and linking form of the aromatic rings. The present invention has been made in order to solve this problem, and it is an object of the present invention to provide an electrical insulating oil composition comprising monocyclic, dicyclic and tricyclic aromatic hydrocarbons at a specific ratio through the use only of a fraction having a specific distillation range, separated by distillation from a mixed fraction of aromatic hydrocarbons produced in a platforming or aromatizing process. [Technical Solution]
According to one aspect of the present invention, it provides an electrical insulating oil composition comprising a component having a distillation range of 280-330 "C, obtained by distilling a mixed fraction of aromatic hydrocarbons produced in a platforming or aromatizing process.
According to another aspect of the present invention, it provides an electrical insulating oil composition, which has a content of aromatic hydrocarbons of 95-100 area percent, as analyzed by HPLC, and has an area ratio of 3-20: 60-94: 3-20 of monocyclic (one-ring) aromatics: bicyclic (two-ring) aromatics: tricyclic (three-ring) aromatics, as analyzed by HPLC, when the aromatic hydrocarbons are classified according to the number of rings into monocyclic aromatics, bicyclic aromatics and tricyclic aromatics.
According to still another aspect of the present invention, it provides an electrical insulating oil composition, which is obtained by distilling a mixed fraction of aromatic hydrocarbons produced in a platforming or aromatizing process and has a viscosity of 4.8-7.1 cSt at 40 °C, a dielectric breakdown voltage of 70-10O kV, and a pour point of less than -40 °C.
Also, said electrical insulating oil composition further comprise at least a compound selected from the group consisting of phenyl xylyl ethanes, benzyl toluenes, dibenzyl toluenes, ethyl biphenyls, ethyl diphenyl ethanes and alkylbenzenes. [Advantageous Effects]
According to the present invention, a high-voltage-withstand electrical insulating oil composition having high stability, excellent low-temperature fluidity and high dielectric breakdown voltage can be obtained by using only a fraction having a specific distillation range, which is separated by distillation from a mixed fraction of aromatic hydrocarbons produced in a process of converting a hydrocarbon mixture into aromatics in the presence of a metal catalyst. In addition, the electrical insulating oil composition according to the present invention may further comprise other electrical insulating oil components, which are conventionally used.
Particularly, the component having the above-specified distillation range consists of monocyclic, bicyclic and tricyclic aromatic hydrocarbons at a specific ratio, and thus is advantageous in that it has high dielectric breakdown voltage and, when impregnated into a film condenser, can significantly increase the potential gradient of the condenser. [Description of Drawings]
FIG. 1 is a process diagram schematically showing one embodiment of a process for preparing electrical insulating oil for film condensers according to the prior art.
FIG. 2 is a process diagram schematically showing one embodiment of a process for preparing electrical insulating oil for film condensers according to the present invention.
FIG. 3 is a graphic diagram showing the comparison of viscosity properties between electrical insulating oils according to Example 1 and Comparative Example 1. FIG. 4 is a graphic diagram showing the comparison of dielectric breakdown voltage properties between electrical insulating oils according to Example 1 and Comparative Example 1. *Description of reference numerals* 10: ethylene, biphenyl; 20: propylene, biphenyl; 30: alkylation reactor; 40: distillation column; 50: mixing unit 100: raw material feeding unit; 200: isomerization reactor 300: distillation column [Best Mode]
Hereinafter, the present invention will be described in further detail with reference to the accompanying drawings.
As described above, the aromatic hydrocarbon-based electrical insulating oil according to the prior invention is obtained as a product resulting from alkylation or transalkylation, and must be subjected to a mixing process for controlling composition after the synthesis process thereof. However, in the present invention, an aromatic fraction converted from a hydrocarbon mixture in the presence of a metal catalyst such as platinum or nickel catalyst is used as a raw material fraction. This fraction has various aromatic hydrocarbon components, and thus it is difficult to analyze all the components. However, to control the properties of electrical insulating oil to exhibit desired physical and electrical properties, a scientific and reasonable standard for analyzing the composition of this fraction is needed, and thus, it is required to obtain a fraction having a specific composition.
Accordingly, in the present invention, the distillation range of a mixed fraction of aromatic hydrocarbons produced in a platforming or aromatizing process is controlled such that only an aromatic fraction comprising a composition having the desired specific properties can be obtained. Also, in the present invention, this aromatic fraction is separated by HPLC into monocyclic aromatics, bicyclic aromatics and tricyclic aromatics and then analyzed, and on the basis of the analysis results, an electrical insulating oil composition having the desired properties is obtained.
The kind of aromatic hydrocarbon determines the stability and fluidity of electrical insulating oil as well as the quantity of evaporation of volatile organic compounds, and thus the control of the composition thereof is very important. For this purpose, only a fraction having a distillation range of 280-330 °C is separated by distillation from a mixed fraction of aromatic hydrocarbons produced in a platforming or aromatizing process, and it preferably has an aromatic hydrocarbon content of 95-100 area percent as analyzed by HPLC, and the area percent ratio of monocyclic aromatics: bicyclic aromatics: tricyclic aromatics in the hydrocarbon fraction is 3-20: 60-94: 3-20 as analyzed by HPLC.
If the content of the monocyclic aromatics in the aromatic hydrocarbon fraction having said composition is too high, the nature of aliphatic hydrocarbon in the fraction will be increased, resulting in a decrease in the hydrogen gas-absorbing capability or low-temperature fluidity of the fraction. On the other hand, if it is lower than that of the specified composition, the composition will have increased viscosity at a temperature higher than room temperature, and a strong odor.
Also, if the content of the tricyclic aromatics is higher than that of the above-specified composition, the amount of components that precipitate as crystals at low temperature will be increased, leading to a decrease in durability to partial electric discharge, and if it is lower than that of the above composition, the density of the oil composition will be decreased, leading to a decrease in voltage-withstand capability at a temperature higher than room temperature.
Meanwhile, if the content of the main component bicyclic aromatics deviates from the above range, the oil composition will have low density and a strong odor, and thus, for example, a working environment problem can be caused by the odor, emitted through a vacuum degasser in a process of making film condensers. Li connection with this, FIG. 2 schematically shows one preferred embodiment of a process for preparing electrical insulating oil according to the present invention.
As referred by Fig 2, a hydrocarbon mixture, for example, naphtha is fed through a raw material feeding unit 100 into an isomerization reactor 200, in which it is converted into aromatics in the presence of a metal catalyst such as platinum or nickel. Then, the resulting aromatic fraction is fed into a distillation column 300, in which it is distilled in a vacuum to be within the distillation range of 280-330 0C .
If the distillation range deviates from the above range, the low-temperature fluidity or flash point of the insulating oil will be decreased, leading to a decrease in stability, and the odor intensity of the insulating oil will be increased, deteriorating the working environment. In this case, it is preferable to keep the distillation condition such that the overhead temperature of the distillation column 300 does not exceed 290 °C . Meanwhile, if discoloration or odor of the insulating oil occurs due to an excessively high overhead temperature, it can be removed by adsorption or gas scrubbing in a subsequent process.
The fraction having a distillation range of 280-330 °C preferably has a viscosity of 4.8- 7.1 cSt at 40
Figure imgf000009_0001
then ^O °C .
If necessary, the electrical insulating oil composition according to the present invention may further comprise at least one compound selected from the group consisting of components used as electrical insulating oils in the prior art, for example, phenyl xylyl ethane, benzyl toluene, dibenzyl toluene, ethyl biphenyl, ethyl diphenyl ethane, and alkyl benzene. This component can be used in an amount of about 30-60 wt% based on the weight of the electrical insulating oil composition, but the present invention is not specifically limited thereto.
The electrical insulating oil of the present invention is used after removing water therefrom by a conventional method. Conventional methods of removing water include vacuum spray degassing, thin film vacuum degassing, and molecular sieve methods, but the present invention is not specifically limited thereto.
As described above, according to the present invention, the high-voltage-withstand electrical insulating oil having high stability, excellent low-temperature fluidity and high dielectric breakdown voltage can be obtained using a fraction having a specific distillation range, which is separated by distillation from a mixed fraction of aromatic hydrocarbons produced in a process of converting a hydrocarbon mixture into aromatics in the presence of a metal catalyst. Particularly, said fraction having a specific distillation range consists of monocyclic, bicyclic and tricyclic aromatic hydrocarbons at a specific ratio, and thus is advantageous in that it has high dielectric breakdown voltage and, when impregnated into a film condenser, can significantly increase the potential gradient of the condenser. [Mode for Invention]
Hereinafter, the present invention will be described in further detail with reference to examples, but the scope of the present invention is not limited thereto. Example 1
Naphtha as a raw material was converted into aromatics through a reforming process at a pressure of 3 kg/cm2 and a temperature of 500 "C in the presence of a platinum catalyst, and then an aromatic fraction was separated from the aromatics through a liquid-liquid extraction process. The separated aromatic fraction was continuously distilled using two distillation columns having a theoretical plate number of 60 to obtain a composition having a distillation range of 280-330 "C and an aromatic content of 99 area percent as analyzed by HPLC. The composition was used as electrical insulating oil, and its physical properties and dielectric breakdown voltage are measured to show in Table 1 below as a measurement result. Also, the viscosity properties depending on change in temperature of the obtained electrical insulating oil are shown in FIG. 3, and the dielectric breakdown voltage properties thereof are shown in FIG. 4.
Example 2 A composition was obtained in the same manner as in Example 1, except that the distillation range was controlled to 290-330 °C. The obtained composition was used as electrical insulating oil, and its physical properties and dielectric breakdown voltage are measured to show in Table 1 below as a measurement result.
Example 3 A composition was obtained in the same manner as in Example 1, except that the distillation range was controlled to 290-320 °C. The obtained composition was used as electrical insulating oil, and its physical properties and dielectric breakdown voltage are measured to show in Table 1 below as a measurement result.
Comparative Example 1
The physical properties and dielectric breakdown voltage of phenyl xylyl ethane, a kind of bycyclic aromatic, among electrical insulating oils used in the prior art, were measured, and the measurement results are shown in Table 1 below. Also, the viscosity properties depending on the change in temperature of electrical insulating oil obtained from the composition are shown in FIG. 3, and the dielectric breakdown voltage properties thereof are shown in FIG. 4.
[Table 1]
Physical properties
Figure imgf000011_0001
*: Composition was measured using HPLC, and the measurement results are expressed as area percent. As can be seen in Table 1 and FIGS. 3 and 4, the electrical insulating oil according to the present invention has low viscosity even at low temperature, and high dielectric breakdown voltage, indicating excellent electrical insulating properties.
Although the present invention has been described in detail with reference to specific embodiments, those skilled in the art will appreciate that these embodiments are for illustrative purposes only, that the electrical insulating oil composition according to the present invention is not limited thereto, and that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims.

Claims

[CLAIMS] [Claim 1]
An electrical insulating oil composition comprising a component having a distillation range of 280-330 °C, obtained by distilling a mixed traction of aromatic hydrocarbons produced in a platforming or aromatizing process. [Claim 2]
An electrical insulating oil composition, which has an aromatic hydrocarbon content of 95-100 area percent, as analyzed by HPLC, and has an area ratio of 3-20: 60-94: 3-20 of monocyclic aromatics: bicyclic aromatics: tricyclic aromatics, as analyzed by HPLC, when the aromatic hydrocarbons are classified according to the number of rings into monocyclic aromatics, bicyclic aromatics and tricyclic aromatics. [Claim 3]
An electrical insulating oil composition, which is obtained by distilling a mixed fraction of aromatic hydrocarbons produced in a platforming or aromatizing process, and has a viscosity of 4.8-7.I cSt at 40 °C, a dielectric breakdown voltage of 70-10O kV, and a pour point of -40 °C or less. [Claim 4]
The electrical insulating oil composition of any one of Claims 1 to 3, which further comprises at least one compound selected from the group consisting of phenyl xylyl ethanes, benzyl toluenes, dibenzyl toluenes, ethyl biphenyls, ethyl diphenyl ethanes and alkylbenzenes.
PCT/KR2006/005113 2006-01-12 2006-11-30 Heavy aromatic electrical insulation oil with high breakdown voltage WO2007081088A1 (en)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101784646A (en) * 2007-07-31 2010-07-21 雪佛龙美国公司 Electric insulation oil composition and preparation thereof
US8731845B2 (en) 2008-08-15 2014-05-20 Visionpharm A/S Method and a system for determining a target in a biological sample by image analysis

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101317594B1 (en) * 2007-10-26 2013-10-11 에스케이종합화학 주식회사 Electrical insulation oil composition having improved hydrogen absorptiveness
CN101854786A (en) * 2010-06-03 2010-10-06 湖南威铭能源科技有限公司 Waterproof and moistureproof sealing method of circuit board
FR3008708B1 (en) * 2013-07-19 2016-09-23 Arkema France COMPOSITION OF DIELECTRIC FLUID OR CALOPORATOR
CN111218304A (en) * 2018-11-23 2020-06-02 中国石油天然气股份有限公司 Insulating oil base oil, preparation method thereof and insulating oil
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Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6072207A (en) * 1991-02-25 2000-06-06 Symetrix Corporation Process for fabricating layered superlattice materials and making electronic devices including same
US6265495B1 (en) * 1998-09-22 2001-07-24 Nippon Shokubai Co., Ltd. Method for production of esterified product
US6323277B1 (en) * 1998-04-17 2001-11-27 Witco Corporation Bridged silicone oligomers and curable compositions containing same

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4033854A (en) * 1974-12-02 1977-07-05 Nippon Oil Company, Ltd. Electrical insulating oils
JPS6015086B2 (en) * 1977-04-13 1985-04-17 日本石油化学株式会社 Method for producing electrical insulating oil
JPS5750710A (en) * 1980-09-11 1982-03-25 Nippon Petrochemicals Co Ltd Electric insulating coil composition
JPH06101245B2 (en) * 1984-08-03 1994-12-12 日本石油化学株式会社 Method for producing electric insulating oil

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6072207A (en) * 1991-02-25 2000-06-06 Symetrix Corporation Process for fabricating layered superlattice materials and making electronic devices including same
US6323277B1 (en) * 1998-04-17 2001-11-27 Witco Corporation Bridged silicone oligomers and curable compositions containing same
US6265495B1 (en) * 1998-09-22 2001-07-24 Nippon Shokubai Co., Ltd. Method for production of esterified product

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101784646A (en) * 2007-07-31 2010-07-21 雪佛龙美国公司 Electric insulation oil composition and preparation thereof
US8731845B2 (en) 2008-08-15 2014-05-20 Visionpharm A/S Method and a system for determining a target in a biological sample by image analysis

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