Classifications

• • 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
  • C10G67/00—Treatment of hydrocarbon oils by at least one hydrotreatment process and at least one process for refining in the absence of hydrogen only
  • C10G67/02—Treatment of hydrocarbon oils by at least one hydrotreatment process and at least one process for refining in the absence of hydrogen only plural serial stages only
  • C10G67/04—Treatment of hydrocarbon oils by at least one hydrotreatment process and at least one process for refining in the absence of hydrogen only plural serial stages only including solvent extraction as the refining step in the absence of hydrogen
  • C10G67/0409—Extraction of unsaturated 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
  • C10G21/00—Refining of hydrocarbon oils, in the absence of hydrogen, by extraction with selective solvents
• • 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
  • C10G47/00—Cracking of hydrocarbon oils, in the presence of hydrogen or hydrogen- generating compounds, to obtain lower boiling fractions
  • C10G47/02—Cracking of hydrocarbon oils, in the presence of hydrogen or hydrogen- generating compounds, to obtain lower boiling fractions characterised by the catalyst used
  • C10G47/10—Cracking of hydrocarbon oils, in the presence of hydrogen or hydrogen- generating compounds, to obtain lower boiling fractions characterised by the catalyst used with catalysts deposited on a carrier
  • C10G47/12—Inorganic carriers
  • C10G47/16—Crystalline alumino-silicate carriers
  • C10G47/18—Crystalline alumino-silicate carriers the catalyst containing platinum group metals or compounds thereof

Definitions

• Lube oils of improved viscosity index are produced in good yield by subjecting a lube oil charge stock to solvent extraction, hydrorefining the aromatic-rich extract, recombining the hydrorefined extract with the feed or the ratiinate and then dewaxing.
• This invention relates to the production of lubricating oils. More particularly it is concerned with the conversion of low quality lubricating oil stocks into lubricating oils of high viscosity index in good yields.
• the lube oil stock obtained either by vacuum distillation or by deasphalting a vacuum residuum can be improved by solvent extraction to increase the viscosity index and by solvent dewaxing to lower the pour point.
• Acid treating may be used to improve the color, the stability and the resistance of the oil to oxidation and clay contacting is used to further improve the color and to neutralize the oil after acid treatment.
• More recently severe catalytic hydrogenation of the oil has been proposed as a substitute for solvent refining to increase the viscosity index of the oil.
• the resulting product oil is not stable towards ultra-violet light and with certain feedstocks, relatively low yields are obtained.
• a process for the production of lubricating oils which comprises subjecting a lubricating oil charge stock to solvent refining to produce a raffinate rich in paraflins and naphthenes and an extract rich in aromatics, contacting the extract with a hydrorefining catalyst under hydrorefining conditions and combining at least a portion of the hydrorefined extract with said raffinate or recycling it to the solvent refining step.
• Examples of the lubricating oil charge stock contemplated by our process are petroleum fractions having a viscosity between 50 and 500 SUS at 210 F.
• the invention is applicable to any lubricating oil charge stock, it is particularly suitable for the treatment of medium-quality charge stocks, that is, those charge stocks having a viscosity index not greater than about and more particularly for the treatment of low-quality charge stocks, that is, those having a viscosity index below about 80 to produce improved lubricating oils having a viscosity index at least 20 units higher than that of the charge stock.
• Lubricating oil stocks are ordinarily obtained from the distillation of crude petroleum.
• the stock may be obtained as overhead from a vacuum distillation or may be obtained from the residue from vacuum distillation by deasphalting the residue by contact with, for example, a deasphalting agent such as propane, butane and the like and mixtures thereof.
• a deasphalting agent such as propane, butane and the like and mixtures thereof.
• the lubricating oil fraction is subjected to solvent extraction using a solvent having an afiinity for aromatic hydrocarbons.
• Particularly suitable solvents include furfural, phenol, dichloroethyl ether and N-methyl-Z-pyrrolidone.
• the extraction is carried out using a countercurrent flow technique, the solvent being introduced at the top of an extraction tower and the oil near the bottom with the tower being maintained at a temperature between about and 250 F.
• the solvent to oil ratio may range between about 1 to 6 by volume.
• Oil is recovered from the top of the tower as ratiinate and is advantageously further processed by heating and steam stripping to remove residual solvent.
• Solvent and extract are removed from the bottom of the extraction tower and are separated by distillation.
• the extract is then subjected to catalytic hydro-refining at a temperature between about 600 and 900 F., a pressure between about 800 and 5000 p.s.i.g., a space velocity of about 0.1 to 5.0 volumes of oil per volume of catalyst per hour with a hydrogen rate of between about 1500 and 20,000 standard cubic feet per barrel of charge.
• the temperature is maintained within the range of 650-830 F., the pressure between 1300 and 3,000 p.s.i.g., the space velocity between 0.15 and 1.5, (v./v./hr.) and the hydrogen rate between 3,000 and 10,000 s.c.f.b
• the gas used for the hydrogenation need not necessarily be pure hydrogen. Hydrogen having a purity of at least 65 percent and preferably at least 75 percent may be used.
• the catalysts used in the hydrorefining step generally comprise a hydrogenating component carried on a support.
• the principal ingredient of the hydrogenating component is a Group VIII metal or mixtures of Group VIII metals or compounds thereot such as the oxides or sulfides.
• Group VIII metals which may be used in the hydrogenating component are nickel, cobalt and iron or mixtures thereof.
• the iron group metal should be present in an amount between about 2 and 40 percent preferably 3-15 percent based on the total weight of the catalyst composite.
• a Group VI metal such as molybdenum or tungsten may be used. In such case the Group VI metal may be present in an amount between about 5 and 40 percent based on the Weight of the composite, a preferred range being from 10 to 25 percent.
• the hydrogenating component is carried on a base comprising a refractory inorganic oxide material such as alumina, silica, magnesia, zirconia, titania, crystalline alumino silicates and the like and mixtures thereof.
• a refractory inorganic oxide material such as alumina, silica, magnesia, zirconia, titania, crystalline alumino silicates and the like and mixtures thereof.
• the catalyst has an acidic support such as a crystalline alumino silicate of the zeolite Y type of reduced alkali metal content, e.g., less than 1.0 weight percent composited with a mixture of an amorphous inorganic oxide material such as 7090% silica and 10-30% alumina. If the extract has been obtained from a wax distillate, then advantageously the catalyst support has little if any cracking activity.
• an acidic support such as a crystalline alumino silicate of the zeolite Y type of reduced alkali metal content, e.g., less than 1.0 weight percent composited with a mixture of an amorphous inorganic oxide material such as 7090% silica and 10-30% alumina.
• the catalyst has cracking activity which on occasion it may be desired to suppress, then a small amount of ammonia or carbon monoxide may be added to the hydrogen.
• a suitable amount depending on the extent to which the cracking is to be suppressed will range between about 0.1 and 2.0 percent ammonia or carbon monoxide basis reactor feed gas.
• the catalyst may be used in the form of a slurry, a fluidized bed or a fixed bed. When used in the form of a fixed bed, the oil and hydrogen flow may be either upward or downward or the flow of hydrogen may be countercurrent to the downward flow of oil.
• the catalysts covered by the scope of this invention are those which have suitable activity for carrying out the reactions described herein.
• catalysts include those containing from 2 to 10 percent cobalt or nickel and 10 to 30 percent molybdenum or tungsten.
• Particularly suitable catalysts are those containing about 6 percent nickel and 20 percent tungsten or about 5 percent nickel or cobalt and about 12-15% molybdenum.
• the hydrorefined extract after being subjected to a separation treatment for the removal of hydrogen and light distillates is recycled to the solvent refining zone into which it is introduced with fresh feed.
• the hydrorefined extract, after separation of the lighter materials is combined with the rafiiniate from the solvent extraction zone and the combined stream is subjected to solvent dewaxing.
• the oil is contacted with a dewaxing agent such as a mixture of equal parts of a ketone, for example, acetone or methylethyl ketone and an aromatic compound such as benzene or toluene, in a ratio of about 3 to 4 parts by volume of solvent per volume of oil.
• a dewaxing agent such as a mixture of equal parts of a ketone, for example, acetone or methylethyl ketone and an aromatic compound such as benzene or toluene, in a ratio of about 3 to 4 parts by volume of solvent per volume of oil.
• the mixture is cooled to a temperature of about to --20 F. depending upon the desired pour point and the waxy components are removed from the chilled mixture by filtering or by centrifuging.
• the dewaxed liquid is then subjected to flash distillation and stripping to remove the solvent.
• the hydrorefining may be elfected in multiple stages.
• the extract is subjected in the first stage to a prehydrogenation adapted particularly to saturate aromatic compounds and the hydrogenated product is then subjected to catalytic hydrocracking in the second stage.
• the first stage catalyst comprises a conventional hydrogenation component on a support such as alumina which has minimum cracking activity and the second stage utilizes a hydrocracking catalyst comprising a hydrogenation component on a support which is acidic in nature and is adapted to effect considerable conversion of the product from the prehydrogenation zone into lower molecular weight compounds.
• Such a second stage catalyst may comprise 0.1-5 weight percent platinum or palladium and 0.1-5% rhenium on a support such as low alkali metal content zeolite in admixture with one or more amorphous inorganic oxides such as a mixture of silica and alumina containing 70-90 weight percent silica and 10-30 weight percent aluminum.
• the ratliniate in addition to solvent dew-axing, may be subjected to a hydrofinishing treatment which is a hydrogenation under quite mild conditions, generally, a temperature between about 400 and 650 F. and a pressure between about 400 and 1500 p.s.i.g.
• the catalyst used for the hydrofinishing treatment may be the same as the catalyst used for the prehydrogenation of the extract or a catalyst similar thereto.
• the hydrofinishing treatment is used particularly when the hydrorefined extract is combined with the rafiiniate rather than recycled to the solvent extraction step.
• the hydrofinishing treatment may precede or may follow the solvent dewaxing step. However, regardless of the sequence of the solvent dewaxing and the hydrofinishing, the hydrorefined extract is combined with the raffinate prior to the solvent dewaxing step.
• the charge is brought into contact with a catalyst composed of 6% nickel and 21% tungsten on a support composed of 22% decationized hydrogen form zeolite Y, 65% silica and 13% alumina, at a temperature of 680 F., a pressure of 1800 p.s.i.g., a space velocity of 1.0 v./v./hr. and a hydrogen rate of 6000 s.c.f.b.
• the lube oil cut is dewaxed by mixing it with a 50-50 mixture of methyl ethyl ketone and toluene, cooling the mixture to a temperature of -10 F., filtering the mixture and distilling off the solvents.
• the dewaxed oil is then solvent extracted with N-methyl-Z-pyrrolidone at a solvent-to-oil ratio of 2:1 and a temperature of 180 F. to obtain a product having a viscosity index of 107.
• the characteristics of the intermediate and final products are set forth below in Table 2:
• EXAMPLE II (1) Railinate (2) Extract (3) Hydrorefined extract (4) Raffinate hydrorefined extract (5) Dewaxed oil TABLE 3 Viscosity, BUS/210 F 39 44. 7 46 Viscosity index 100 114 107 Pour point, F 60 90 Yield, volume percent basis feed 58 42 34 92 69
• the product from Example II shows good stability toward ultraviolet light. It is also to be noted that although the product oils from Examples I and II have substantially the same characteristics, the product of Example II is obtained in a yield 25% greater than that of Example I.
• EXAMPLE III This example is a repeat of Example II with the exception that the hydrogenated extract instead of being combined with the rafiinate is recycled to the solvent extraction zone.
• a product oil similar to that set forth in Column of Table 3 is obtained with the exception that the product oil is obtained in a yield of 73% basis feed.
• a process for the production of a lubricating oil of improved viscosity index which comprises passing a lubricating-oil reactant stream through a solvent extraction zone, separating from said reactant stream an aromatic 6 rich extract then passing said reactant stream through a dewaxing zone to decrease the pour point thereof, subjecting said aromatic rich extract to hydrorefining by contacting same with a catalyst comprising an iron group metal or compound thereof supported on a base having cracking activity comprising a crystalline alumino-silicate of reduced alkali metal content at a temperature between 650 and 830 F. in the presence of added hydrogen and combining the hydrorefined extract with the reactant stream prior to its introduction into said dewaxing zone.

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• Chemical & Material Sciences (AREA)
• Oil, Petroleum & Natural Gas (AREA)
• Engineering & Computer Science (AREA)
• Chemical Kinetics & Catalysis (AREA)
• General Chemical & Material Sciences (AREA)
• Organic Chemistry (AREA)
• Crystallography & Structural Chemistry (AREA)
• Inorganic Chemistry (AREA)
• Production Of Liquid Hydrocarbon Mixture For Refining Petroleum (AREA)

Applications Claiming Priority (1)

Publications (1)

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ID=22145177

Family Applications (1)

Country Status (16)

Cited By (12)

Families Citing this family (2)

• 1970
  • 1970-10-06 US US78614A patent/US3702817A/en not_active Expired - Lifetime
• 1971
  • 1971-08-17 CA CA120,773A patent/CA961434A/en not_active Expired
  • 1971-09-02 DE DE19712143972 patent/DE2143972A1/de active Pending
  • 1971-09-09 GB GB4202371A patent/GB1310488A/en not_active Expired
  • 1971-09-10 ZA ZA716069A patent/ZA716069B/xx unknown
  • 1971-09-20 AU AU33670/71A patent/AU449858B2/en not_active Expired
  • 1971-09-27 BE BE773152A patent/BE773152A/fr unknown
  • 1971-09-29 FR FR7135025A patent/FR2112259B1/fr not_active Expired
  • 1971-10-01 TR TR16796A patent/TR16796A/xx unknown
  • 1971-10-04 IT IT29459/71A patent/IT938939B/it active
  • 1971-10-04 NL NL7113567.A patent/NL160875C/xx active
  • 1971-10-04 ES ES395692A patent/ES395692A1/es not_active Expired
  • 1971-10-05 BR BR6608/71A patent/BR7106608D0/pt unknown
  • 1971-10-05 SE SE7112599A patent/SE373151B/xx unknown
  • 1971-10-06 JP JP46077976A patent/JPS513321B1/ja active Pending
  • 1971-10-06 AR AR238339A patent/AR209251A1/es active

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