Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J29/00—Catalysts comprising molecular sieves
  • B01J29/04—Catalysts comprising molecular sieves having base-exchange properties, e.g. crystalline zeolites
  • B01J29/06—Crystalline aluminosilicate zeolites; Isomorphous compounds thereof
  • B01J29/18—Crystalline aluminosilicate zeolites; Isomorphous compounds thereof of the mordenite type
• • 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
  • C10G45/00—Refining of hydrocarbon oils using hydrogen or hydrogen-generating compounds
  • C10G45/58—Refining of hydrocarbon oils using hydrogen or hydrogen-generating compounds to change the structural skeleton of some of the hydrocarbon content without cracking the other hydrocarbons present, e.g. lowering pour point; Selective hydrocracking of normal paraffins
  • C10G45/60—Refining of hydrocarbon oils using hydrogen or hydrogen-generating compounds to change the structural skeleton of some of the hydrocarbon content without cracking the other hydrocarbons present, e.g. lowering pour point; Selective hydrocracking of normal paraffins characterised by the catalyst used
  • C10G45/64—Refining of hydrocarbon oils using hydrogen or hydrogen-generating compounds to change the structural skeleton of some of the hydrocarbon content without cracking the other hydrocarbons present, e.g. lowering pour point; Selective hydrocracking of normal paraffins characterised by the catalyst used containing crystalline alumino-silicates, e.g. molecular sieves
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10L—FUELS NOT OTHERWISE PROVIDED FOR; NATURAL GAS; SYNTHETIC NATURAL GAS OBTAINED BY PROCESSES NOT COVERED BY SUBCLASSES C10G OR C10K; LIQUIFIED PETROLEUM GAS; USE OF ADDITIVES TO FUELS OR FIRES; FIRE-LIGHTERS
  • C10L1/00—Liquid carbonaceous fuels
  • C10L1/04—Liquid carbonaceous fuels essentially based on blends of hydrocarbons
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10S208/00—Mineral oils: processes and products
  • Y10S208/02—Molecular sieve

Definitions

• Fuel oils or fuel oil components are produced from waxy atmospheric residues by vacuum distilling the residue to give a wax distillate fraction and a vacuum residue, selectively dewaxing the wax distillate fraction and reblending at least a portion of the dewaxed wax distillate fraction with at least a portion of the vacuum residue.
• the process is particularly suitable for atmospheric residues with 1535% wt. wax.
• the preferred selective dewaxing process is catalytic, involving passing the wax distillate with hydrogen over a catalyst of a Group VIa and/ or Group VIII hydrogenating component incorporated with mordenite of reduced alkali metal content.
• the mordenite is preferably decationised and has a SiO :Al O ratio of at least 14:1.
• the dewaxing conditions may be 450-950 F, 250-3000 p.s.i.g., 0.2-20 v./v./hr. and 1000-3000 s.c.f. of H /B.
• This invention relates to the production of fuel oils from waxy residues.
• Fuel oils are heavy petroleum fractions and usually atmospheric residues diluted with lower boiling fractions, where necessary, to reduce viscosity. Their composition is not critical as such except in so far as the composition affects the handling and storage of the oils. Currently most fuel oils are required to meet a maximum pour point limit between and 70 F. depending on the viscosity grade which is usually within the range 200 to 3500 Redwood No. 1 seconds at 100 F. (13 to 93 est. at 170 F.). This means that atmospheric residues from certain waxy crude oils cannot be used directly as fuel oils. This is regrettable since these waxy crudes often have low sulphur contents, which is a desirable property in view of the current emphasis on reducing atmospheric pollution.
• a method of making residues from waxy crude oils suitable for use as fuel oils or components of fuel oils is thus potentially useful. Since the high pour points of the waxy crude oils are due to their high wax contents, dewaxing would be one such method, but dewaxing the whole of an atmospheric residue would be costly.
• a process for the production of fuel oils or fuel oil components comprises distilling an atmospheric residue, containing at least 5% wt. of wax and having an initial boiling point within the range 320370 C., under vacuum to give a wax distillate fraction having an initial boiling point of 320-370 C. and a final boiling point of 500- 600 C. and vacuum residue constituting the remainder of the atmospheric residue, selectively dewaxing the wax distillate cut to reduce the wax content of the wax distillate by at least 4% wt. and blending at least a proportion of the dewaxed wax distillate with at least a ice proportion of the vacuum residue to give fuel oil or a fuel oil component.
• the wax distillate is selectively dewaxed so that the desirable lower-boiling, low viscosity, components are not unnecessarily destroyed.
• the dewaxing may thus be a solvent dewaxing process (using, for example, as solvents chlorinated hydrocarbons, lower alkyl ketones with or without an aromatic such as benzene or toluene, and lower boiling alkanes) or urea adduction.
• the dewaxing is a catalytic dewaxing over a catalyst based on a particular zeolite, mordenite, which has the unusual characteristic of selectively cracking waxy hydrocarbons.
• the process may be similar to that described and claimed in U.K. patent specification No. 1,088,933 and the complete specification of U.K. patent application No. 53,783/66. (Now U.K. patent specification No. 1,134,014.)
• the wax distillate may therefore be passed at elevated temperature and pressure and in the presence of hydrogen over a catalyst comprising one or more hydrogenating components selected from Groups VIa and VIII of the Periodic Table incorporated with a crystalline mordenite of reduced alkali metal content.
• crystalline mordenite of reduced alkali metal content means, preferably, a mordenite with an alkali metal content of less than 3% wt.
• the deficiency of alkali metal cations can be made up with other metal cations for example Group II metal cations, particularly magnesium, or rare earth metal cations.
• the mordenite is a decationized mordenite, which means a mordenite having a deficiency of metal cations.
• An alternative term in the art is hydrogen mordenite, since it is assumed that when metal cations are removed they are replaced by hydrogen ions. However, since it is not possible to detect the presence of hydrogen ions in zeolites, the precise structure remains in doubt. A cation deficiency can, on the other hand, be readily measured by analysis of the metallic elements present in the zeolite.
• Me is a metal cation
• 12 is the valency of the cation
• X is variable between nil and 7 depending on the thermal history of the sample.
• Me is commonly sodium and in one common form of decationisation sodium mordenite is base exchanged with ammonium cations. The ammonium form is then heated to drive off ammonia, leaving behind the hydrogen form or decationised mordenite.
• the mordenite may be treated with a mineral acid, for example hydrochloric or sulphuric acid, in order directly to decationise the mordenite.
• a combination of acid treatment and ammonium treatment can also be used.
• the decationized mordenite used in the present invention has a higher than normal silicazalumina ratio of at least 14:1.
• ratios of as :1 have been obtained and a practical upper limit may thus be :1.
• Particularly preferred silica:alumina ratios are in the range 16:1 to 50:1.
• the mordenite used in the present invention having a higher than normal silicazalumina ratio is obtained by treatment of a metal cationcontaining mordenite, particularly sodium mordenite, with a trong acid, for example sulphuric or hydrochloric acid, of from 550% wt. strength and preferably from 10 to 20% wt. strength.
• a single treatment or two or more 3 successive treatments may be given with acids of the strengths stated above.
• a convenient method of treatment is to treat the mordenite with acid under reflux for a period of 2-12 hours.
• the metal cation content for example the sodium cation contact, should be less than 2% wt. of the mordenite and preferably less than 1.5% wt. of the mordenite.
• the hydrogenating component is preferably a platinum group metal, particularly platinum or palladium, and it is preferably added by ion-exchange.
• the mordenite is aged in water before adding the platinum group metal as described in the specification of U.K. application No. 4,421/68.
• the amount of the platinum group metal is preferably within the range 0.01 to 10% wt., particularly 0.1 to wt.
• iron group metals, particularly nickel may also give useful results. Mixtures of certain Group VI and VIII metals and compounds may also be used, e. g. cobalt and molybdenum.
• the catalyst is preferably calcined at for example 250- 600 C. before use to remove any water and to eliminate any ligands attached to the hydrogenation component.
• Sulphur and nitrogen compounds do not have to be removed before the catalytic dewaxing, but it may be desirable to scrub recycle gases to remove any hydrogen sulphide and ammonia produced.
• Suitable process conditions include a temperature within the range 450-950 R, (232-510" C.) preferably 500- 850 F., (260454 C.) a pressure within the range 250- 3000 p.s.i.g, preferable 500-2500 p.s.i.g, a space velocity between 0.2-20.0 -v./v./hr., preferably 0.4-8.0 v./v./hr., and a gas rate of %-30,000 s.c.f. of hydrogen/B preferably 5000-15,000 s.c.f. of hydrogen/ B.
• the precise process conditions in any given situation will depend on the wax content of the feedstock and the extent of wax destruction required.
• the wax is converted mainly to C and C parafiins with some C and only minor amounts of higher hydrocarbons. Separation of the conversion products from the main reaction effluent which is unconverted Wax distillate can thus be a simple stripping operation.
• the wax content as specified in the present invention is defined as the amount of material precipitated from methylene chloride solution at F.
• a known weight of residue is dissolved in hot methylene chloride in a flask, the ratio of methylene chloride to residue being 10:1, (or higher in the case of very high wax content residues).
• the solution of residue in methylene chloride is then cooled to 25 F. and held at this temperature for minutes.
• the precipitated wax is separated by filtration, washed with methylene chloride at -25 F. until the filtrate is colourless.
• redissolved in petroleum ether transferred to the original flask and weighed after evaporation of the petroleum ether.
• the wax content isgiven as percentage by weight on the original residue.
• the pour point of the fuel oil is determined by the Institute of Petroleum Test No. IP/ 15.
• the actual pour point of the finished fuel oil which is required may vary according to the proposed use but in general commercial fuel oil pour points lie in the range of 0 F. to 70 F. Required viscosities of fuel oils within these pour point ranges will normally be 200-3500 Redwood No. 1 seconds at 100 F. (13-90 cs. at 170 F).
• While the present invention may be used with atmospheric residues having as low a wax content as 5% wt. it is particularly suitable for use with feedstocks having a high wax content (i.e. 1535% wt.). As stated earlier. certain high wax content atmospheric residues have low sulphur content of less than 1% wt. and these are par- 4- ticularly preferred feedstocks. With the 15-35% wt. wax feedstocks the reduction in wax content of the wax distillate is preferably at least 10% Wt. e.g. l0-25% wt.
• Examples of high wax content, low sulphur content atmospheric residues are residues derived from certain republicn and Nigerian crude oils.
• the pour points of these residues may be from to F.
• Splitting the residue gives a wax distillate with a pour point within the range 80 to F. and a vacuum residue with a poor point from 80 to 160 F.
• Dewaxing of the wax distillate according to the present invention reduces the pour point to 10-60 F.
• components may also be blended with these components depending on the precise grade of fuel oil required.
• These other components may be high wax content untreated atmospheric residue, atmospheric or vacuum residues derived from other crude oils or gas oil from any convenient source.
• Wax content percent wt 24. 3 26. 7 l9. 9 Yield on atmospheric residue, percent 1 71% vol. yield.
• the wax distillate was catalytically dewaxed over a catalyst of platinum on hydrogen mordenite having the following inspection data
• the run was continued for 370 hours and the products obtained during the periods 44-132 hours on stream and 242-370 hours on stream were stripped of material boiling below C. and analysed with the results shown in Table 2 below.
• the product from 44-132 HOS was called Product A and that from 242-370 HOS, Product B.
• Blends 1 and 3 were blends in the proportion of the Pour point 24 hours after blending) F- 50 45 45 atmospheric residue after allowance had been made for 33; 332% 33;: 3&2; gigggigggw g :2 i8 28 the conversion of the wax in the wax distillate to lighter Pour point (14 days after blending),: F 40 4o 45 material and it will be seen that the pour point of the 15 ,gggg igiggg ggv e blending), f0 'ii blend was the same as that of the dewaxed wax distillate despite the fact that the blend contained nearly 50% of vacuum residue of 155 F. pour point. Blends 2 and 4 used only part of the vacuum residue and gave a blend with a lower pour point than either component.
• mordenite is a decationised mordenite having a metal cation content of less than 2% wt.
• mordenite has a silicazalumina ratio of from 16:1 to 50:1.

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

Applications Claiming Priority (1)

Publications (1)

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ID=9725736

Family Applications (1)

Country Status (6)

Cited By (4)

Families Citing this family (2)

• 1968
  • 1968-01-11 GB GB165568A patent/GB1226131A/en not_active Expired
  • 1968-12-19 US US785381A patent/US3575843A/en not_active Expired - Lifetime
  • 1968-12-24 FR FR1597141D patent/FR1597141A/fr not_active Expired
  • 1968-12-27 NL NL6818768A patent/NL6818768A/xx unknown
• 1969
  • 1969-01-10 DE DE19691901143 patent/DE1901143A1/de active Pending
  • 1969-01-10 BE BE726746D patent/BE726746A/xx unknown

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