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
  • B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
  • B01J37/20—Sulfiding
• • 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
  • B01J27/00—Catalysts comprising the elements or compounds of halogens, sulfur, selenium, tellurium, phosphorus or nitrogen; Catalysts comprising carbon compounds
  • B01J27/02—Sulfur, selenium or tellurium; Compounds thereof
  • B01J27/04—Sulfides
  • B01J27/047—Sulfides with chromium, molybdenum, tungsten or polonium
• • 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
  • B01J27/00—Catalysts comprising the elements or compounds of halogens, sulfur, selenium, tellurium, phosphorus or nitrogen; Catalysts comprising carbon compounds
  • B01J27/02—Sulfur, selenium or tellurium; Compounds thereof
  • B01J27/04—Sulfides
  • B01J27/047—Sulfides with chromium, molybdenum, tungsten or polonium
  • B01J27/051—Molybdenum
• • 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
  • B01J27/00—Catalysts comprising the elements or compounds of halogens, sulfur, selenium, tellurium, phosphorus or nitrogen; Catalysts comprising carbon compounds
  • B01J27/02—Sulfur, selenium or tellurium; Compounds thereof
  • B01J27/04—Sulfides
  • B01J27/047—Sulfides with chromium, molybdenum, tungsten or polonium
  • B01J27/051—Molybdenum
  • B01J27/0515—Molybdenum with iron group metals or platinum group metals
• • 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
  • C10G49/00—Treatment of hydrocarbon oils, in the presence of hydrogen or hydrogen-generating compounds, not provided for in a single one of groups C10G45/02, C10G45/32, C10G45/44, C10G45/58 or C10G47/00
  • C10G49/10—Treatment of hydrocarbon oils, in the presence of hydrogen or hydrogen-generating compounds, not provided for in a single one of groups C10G45/02, C10G45/32, C10G45/44, C10G45/58 or C10G47/00 with moving solid particles
  • C10G49/12—Treatment of hydrocarbon oils, in the presence of hydrogen or hydrogen-generating compounds, not provided for in a single one of groups C10G45/02, C10G45/32, C10G45/44, C10G45/58 or C10G47/00 with moving solid particles suspended in the oil, e.g. slurries

Definitions

• This invention relates to the catalytic hydroprocessing of 04 heavy hydrocarbon oils including crude oils, heavy crude 05 oils and residual oils as well as refractory heavy 06 distillates, including FCC decanted oils and lubricating 07 oils. It also relates to the hydroprocessing of shale oils, 08 oils from tar sands, and liquids derived from coals.
• the 09 invention relates to a catalyst for the hydroprocessing of 10 such hydrocarbonaceous feedstocks, the use of such 11 catalysts, and the preparation of such catalysts.
• the catalyst comprised a dispersed form of molybdenum ,_ disulfide prepared by reacting aqueous ammonia and
• the oil-slurry mixture was then sulfided 30 with hydrogen and hydrogen sulfide at at least two 31 temperatures (Column 24) under certain conditions.
• the feed 32 and catalyst, with water added were charged to the 33 hydroprocessing reactor. Water introduction was deemed 34 beneficial (Columns 26-27) for certain purposes, as was nickel addition to the slurry catalyst (Columns 42-44).
• the dispersed catalyst can be added as an oil/water emulsion 20 prepared by dispersing a water-soluble salt of one or more 21 transition elements in oil.
• the porous contact particles 22 are preferably inexpensive materials such as alumina, porous
• transition metal compounds include _ (NH.) 2 MoO., ammonium heptamolybdate and oxides and sulfides
• the second reaction zone preferably contains a packed or fixed bed of catalysts, and 27 the entire feed to the second reaction zone preferably 28 passes upwardly through the second zone. 29 30
• a lubricating oil base stock boils above about 500 ⁇ F and below about 1300 ⁇ F, and will generally have a kinematic viscosity greater than about 2cS (measured at 100 ⁇ C). A Viscosity Index of about 90 or greater is preferred (ASTM D 2270-86).
• the lubricating oil base stock may be recovered as a distillate or distillate fraction from an upgrading zone, involving processes such as hydrocracking or solvent extraction. 01 Generally, lubricating oil base stocks prepared from 02 hydrocarbon feedstocks boiling above 1000°F require 03 pretreatment prior to the upgrading zone.
• One such 04 pretreatment method is solvent deasphalting, which removes 05 heavy hydrocarbonaceous components which otherwise form 06 precipitates during lube oil processing. The use of these 07 pretreatment methods adds additional processing steps over 08 the process of this invention, and leads to low yields of 09 lubricating oil stocks.
• _ may be further treated to meet specific quality
• Wax may be removed to lower the pour point, 14
• Dewaxing may be carried out by conventional means known in ⁇ the art such as, for example, by solvent dewaxing or by
• Distillates recovered from the 17 upgrading zone may also be further treated with a catalyst in the presence of hydrogen to remove hydrocarbonaceous 18 components which are subject to oxidation and formation of 19 color bodies during storage.
• the present invention provides a high activity catalyst 28 which is prepared by dispersing a slurry catalyst in a 29 hydrocarbonaceous oil for hydroprocessing.
• the present 30 process has the advantage over conventional processes of 31 achieving higher conversion of nitrogen, sulfur, metals and 32 bottoms than fixed bed resid desulfurization, thermal or 33 existing slurry processes.
• 34 01 The process comprises: sulfiding an aqueous mixture of a
• 08 sulfide corresponds to about 1 mole of molybdenum per
• the invention also comprises the preparation of a dispersed
• Group VIB metal sulfide catalyst by sulfiding an aqueous mixture of a Group VIB metal compound with a gas containing
• Group VIII metal compounds improves the denitrogenation 20 capability of the slurry catalyst. 21 22
• a high viscosity index lubricating oil is produced from 23 heavy oils by using our high activity slurry catalyst 24 process.
• the lubricating oil which is produced is of 25 surprisingly high viscosity index and good viscosity.
• the highly active Group VIB metal sulfide 27 catalyst slurry is contacted with feed oil and a hydrogen- 28 containing gas at elevated temperature and pressure; and 29 separating from the product an oil fraction boiling above 30 about 650 ⁇ F which is subsequently dewaxed.
• the process also 31 comprises adding a Group VIII metal compound to the slurry; 32 contacting the slurry catalyst containing the Group VIB and 33 34 the Group VIII metal with a feed oil and a hydrogen- 01 containing gas at elevated temperature and pressure to 02 effect hydroprocessing of said feed oil; and separating a 03 product lubricating oil base stock boiling above about 04 650°F, which is preferably subsequently dewaxed.
• the lubricating oil fraction is of high viscosity index and 07 good viscosity characteristics for lubricating oil base 08 stock.
• Another process using the active catalyst slurry comprises
• the heavy oil is contacted in a first-stage with the active 22 catalyst slurry and hydrogen at a temperature and for a time 23 sufficient to achieve measurable thermal cracking in the 24 product stream.
• the effluent of the first-stage is 25 contacted with a fixed or ebullated bed of 26 desulfurization-demetalation catalyst and hydrogen gas in a 27 second-stage.
• the second-stage catalyst bed may be graded 28 by catalyst activity and/or temperature profile to promote 29 uniform metal deposition, and preferably the effluent stream 30 flows upwardly through the second-stage catalyst bed.
• the catalyst is graded by staged reactors. 32
• the metals are deposited on the slurry 33 catalyst and this catalyst provides the advantage of 34 01 demetalation at lower levels of conversion of the 1000°F+
• the coke yield is less than 2.5%.
• _._ 2-3 show the denitrogenation rate constant, and API gravity l ⁇ increase as a function of the extent of sulfiding,
• ⁇ catalyst precursors which yield active catalysts are aqueous gels.
• Figure 5 shows the benefit of promoting the active
• Figure 7 graphs the percent of vanadium metal removed from 27 residua by the present invention and a competitive process, 28 versus the 1000 ⁇ F+ fraction conversion of the residua. 29 30 31 32 33 34 DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE INVENTION 3 4
• the activity of the Group VIB metal slurry catalyst is a function of the preparation conditions.
• the preferred 5 6 Group VIB metal is molybdenum, but tungsten compounds are 7 also catalytically useful. Molybdenum is used herein for 8 purposes of exemplification and does not exclude other 9 Group VIB compounds.
• the high activity slurry catalyst used 0 in the present invention is described in U.S. Serial 1 No.
• the activity of the final Group VIB metal 7 catalyst is a special function of the activation conditions 8 used to transform the starting Group VIB compound to the 9 final, active catalyst.
• the preferred 1 Group VIB metal, molybdenum and its compounds as typical of 2 our slurry catalyst.
• the reference to molybdenum 3 is by way of preference and exemplification only, and is not 4 01 intended to exclude other Group VIB metals and compounds 02 thereof.
• Catalyst activity is achieved when the extent of sulfiding 19 is from greater than about 8 up to about 14 SCF of hydrogen 20 sulfide per pound of molybdenum. This sulfiding dosage
• Figure 1 shows the denitrogenation 5 activities various catalysts pretreated at essentially the 6 same ammonia to molybdenum ratio but presulfided with 7 various dosages of hydrogen sulfide. These pretreated and 8 sulfided catalysts were screened in a batch reactor with no g added hydrogen sulfide and with a feed that contained little Q sulfur.
• the sulfiding gas consisted of 20%
• catalysts were tested in a batch microactivity unit for 2 ⁇ their denitrogenation, hydrogenation, and desulfurization j .. activities.
• the catalysts were tested at typical catalyst 27 conditions with the gas charge consisting of pure hydrogen.
• This value was slightly lower _.- than that sulfiding dosage required to activate the catalyst - 2 when it is activated under hydrogen partial pressure, ._ i.e. at 12-14 SCF of hydrogen sulfide per pound of 14 molybdenum. Higher API gravities and amounts of hydrogen ⁇ used to upgrade the liquid product were obtained with l ⁇ catalysts sulfided under hydrogen partial pressure.
• molybdenum disulfide is the l ⁇ favored species.
• 21 active catalysts are aqueous gels ( Figure 4) which appear as 2 _ an elastic coherent mass consisting of an aqueous medium in 2 _ which ultramicroscopic particles are either dispersed or
• Optimum catalyst activity occurs when the catalyst precursor is sulfided to the point of incipient gel formation.
• xerogels tend to generate large solid particles when compared with those xerogels prepared from materials produced at the incipient gel formation point.
• a xerogel is defined as a gel containing little or none of the dispersion medium used.
• a Group VIII metal compound be added to the slurry before mixing the slurry with feed oil and a hydrogen containing gas at elevated temperature and pressure.
• Such Group VIII metals are exemplified by nickel and cobalt. It is preferred that the weight ratio of nickel or cobalt to molybdenum range from about 1:100 to about 1:2. It is most preferred that the weight ratio of nickel to molybdenum range from about 1:25 to 1:10, i.e., promoter/ molybdenum of 4-10 weight percent.
• the Group VIII metal exemplified by nickel, is normally added in the form of the sulfate, and preferably added to the slurry after sulfiding at a pH of about 10 or below and preferably at a pH of about 8 or below.
• Group VIII metal nitrates, carbonates or other compounds may also be used.
• the advances of Group VIII metal compound promotion are illustrated in the following examples. In view of the high activity of the slurry catalyst of the present invention the further promotion by Group VIII metal compounds is very advantageous.
• Figure 5 shows the promotion achieved by nickel for the desulfurization and denitrogenation reactions.
• Table III summarizes the operating conditions and results from nickel and cobalt promoted active slurry catalysts of my invention.
• Nickel as wt. % Mo Cobalt as wt. % Mo
• the present invention also relates to the manufacture of lubricating oil base stock from heavy oils characterized by low hydrogen to carbon ratios (i.e., less than about 1:8 by weight) and high carbon residues, asphaltene ⁇ , nitrogen, sulfur and metal contents.
• a heavy oil is that portion of the crude oil boiling above about 650°F.
• Heavy oils are also those oils containing 5% or more of an oil fraction boiling above 1000°F. Examples of such heavy oils include atmospheric and vacuum residua, deasphalted oil and heavy gas oil.
• the catalyst slurry/gel is pumped to the hydroprocessing reactor section where it is contacted with the heavy oil and hydrogen gas.
• Catalyst in oil concentration of from about 0.05 to about 2.0 wt.% molybdenum based on weight of feedstock are preferred when using the high activity slurry catalyst system for lubricating oil production.
• a catalyst in oil concentration of from about 0.3 to 2.0% is more preferred, and most preferably a catalyst in oil concentration of about 1% is used.
• the catalyst and heavy oil are contacted at elevated temperatures and pressures.
• the mixture is reacted at high temperatures and hydrogen partial pressures, normally at about 775 ⁇ F or greater and at a hydrogen partial pressure of about 700-4500 psi, preferably at about 830°F and 2000 psi, respectively. It is under these conditions that high levels of hydrogenation, demetalation, denitrogenation, desulfurization and conversion occur.
• the observed levels of conversion up to 100% are unexpected when compared to those attained in conventional fixed bed technology at equivalent catalyst to oil ratios.
• These levels of conversions surprisingly, produce prime distillate products.
• it is surprising that the 650°F+ product ⁇ have unusually superior lubricating oil properties.
• a lubricating oil fraction boiling above about 650°F is separated. This fraction, ideally suited to lubricating oil base stock manufacture, may be subsequently dewaxed. Additional denitrification of this fraction may also be recommended, in which event it may be subjected to further hydrofinishing using conventional techniques.
• the product of the high activity catalyst hydroprocessing may contain too much wax to be a satisfactory lubricating oil base stock, i.e., have a low pour point, in which event an integral part of our process is a dewaxing step.
• Dewaxing may be carried out by conventional means such as solvent dewaxing or catalytic dewaxing. To facilitate catalytic dewaxing it may be necessary to remove additional nitrogen from the lubricating oil fraction, in which event the use of a hydrotreating or hydrofinishing step should be incorporated into the overall process prior to dewaxing.
• Viscosity Index (VI) 130 It is noteworthy that there was 100% conversion to 1000°F- product. Analysis shows a high paraffinic and a low aromatics level. The nitrogen content indicates that the product would most likely need hydrofinishing to remove nitrogen and provide good stability. Upon removal of nitrogen the wax-rich oil is a good candidate for zeolitic dewaxing. Especially noteworthy was the high yield of dewaxed oil having a viscosity index of 130. This viscosity index is extremely high, especially because the viscosity of the oil is so light (i.e., 16cS @40°C). In general the VI scale severely underrates low viscosity oils.
• An embodiment of the present invention is a two-stage process consisting of a slurry hydroprocessing stage followed by a fixed or ebullated bed desulfurization and demetalation process stage, the slurry hydroprocess is operated at temperatures above the incipient cracking temperature of the heavy oil, normally at temperatures above 700 ⁇ F, preferably 800 to 960°F, and most preferably 830-870°F.
• the second stage or desulfurization reactor is preferably operated in upflow mode to minimize the build-up of slurry catalyst in the bed. Superior performance is achieved in this process by bulk demetalation and carbon residue conversion in the slurry reactor or first stage prior to the heavy oil desulfurization process. Operation of the slurry reactor at temperatures above the incipient cracking temperature of the feed is preferred to achieve this demetalation and carbon residue reduction.
• the first stage or slurry hydroprocessing can be achieved in bubble up-flow reactors, coil crackers or ebullated bed reactors.
• Slurry catalyst systems consist of either small particles, or soluble compounds which yield small particles at reactor conditions dispersed in a feedstock.
• the small solid particles (having a diameter less than 20-50 microns) used in slurry systems can be either catalytically active or inactive for aromatic carbon hydrogenation, or can be auto-catalytic for demetalation, or combinations of the above.
• Inactive slurry systems are particles which are inactive for aromatic carbon hydrogenation and denitrogenation. Some examples of these materials are mineral wastes and spent FCC catalysts or fines. A known mineral waste material for use in slurry systems is "red mud".
• porous contact particles i.e. inactive
• porous contact particles are separately added to the heavy oil feedstock prior to hydroprocessing. Examples of such porous contact particles include spent FCC catalyst particles, or fines.
• Slurry catalyst systems can be produced during hydroprocessing by either thermal decomposition or reaction with hydrogen/hydrogen sulfide gas mixtures. These systems consist of either oil or water-soluble metal compounds.
• the water-soluble compound can be either mixed directly into the oil or emulsified with added surfactants. Generally the water-soluble compounds are preferred due to their lower cost when compared to the organic compounds.
• Auto-catalytic slurry systems for demetalation reactions are exemplified by such materials as nickel/vanadium oxides or sulfides or oxysulfides which act as demetalation catalysts and can thus be classified as auto-catalytic materials. Addition of nickel and vanadium sulfides to the oil not only increases the demetalation reactions but also initiates the auto-catalytic demetalation reaction.
• the Group VIB metal activated slurry catalyst of the present invention preferably promoted by Group VIII metal compounds, provides a substantial improvement to a slurry catalyst system's hydrogenation, denitrogenation, carbon residue conversion and demetalation performance.
• the catalyst precursors prepared by the methods used in this invention are characterized by extremely small particle size distributions. The bulk of these particles are in the sub-micron range.
• An embodiment of the present invention operates in one or two stages.
• the heavy oil is contacted with the active catalyst slurry and a hydrogen-containing gas at elevated temperatures and pressures and proceeds directly to a fixed or ebullated bed catalytic reactor with sufficient residence time in the catalytic reactor and at temperatures sufficient to achieve measurable thermal cracking rates.
• the process may be operated in two-stages where the first-stage comprises the contacting of the active catalyst slurry with the heavy oil and a hydrogen-containing gas with sufficient time and temperature in a thermal treatment reactor, such as a thermal coil or a bubble up-flow column or an ebullated reactor, to achieve reasonable thermal cracking rates.
• a thermal treatment reactor such as a thermal coil or a bubble up-flow column or an ebullated reactor
• the concentration of the active slurry catalyst in the heavy oil is normally from about 100 to 10,000 ppm expressed as 05 weight of metal (molybdenum) to weight of heavy oil 06 feedstock. Demetalation of the heavy oil to the extent of 07 08 greater than 30% metals removal can be obtained even with 09 less than 50% conversion of the 1000°F+ fraction when the 10 catalyst concentration is in this range, and surprisingly,
• the coke yield can be maintained at less than l about 2.5 percent.
• the process conditions for the second-stage or fixed bed 19 reactor are typical of heavy oil desulfurization conditions 20 except that the preferred flow regime is preferably 21 cocurrent up-flow to minimize the build-up of solids in the 22 bed.
• the second-stage reactor may be either a fixed, 23 ebullated or a moving bed reactor.
• the catalyst used in the 24 second stage reactor is a hydrodesulfurization-demetalation 25 catalyst such as those containing a Group VI and/or a 26 Group VIII metal deposited on a refractory metal oxide. 27 Examples of such catalysts are described in U.S. 28 Patents 4,456,701 and 4,466,574 incorporated herein by 29 reference.
• the process conditions for typical one- and 30 two-stage operations are listed in Table VII. 31 32 33 34 TABLE VII
• H2 Pressure ⁇ 200 to 4500 psi. > Recycle Gas Rate: 500 - 2500 SCFB 1500 - 15000 SCFB LHSV, Vol/Hr/Vol: 0.10 - 6.0 1/Hr Coil Volume 0.005 - 0.045 Cu.Ft/Bbl./Day:
• H2 Pressure 1000 - 4500 psi.
• TCHC signifies a run 10 made by the thermal catalytic hydroconversion (TCHC) process using a slurry catalyst which is the relatively inactive 11 2 ammonium heptamolybdate.
• the process run 13 labeled ACTIVE corresponds to the use of the active catalyst _.. slurry of the present invention.
• the relatively l ⁇ inactive slurry catalyst was an aqueous ammonium _._- heptamolybdate mixed with a succinimide surfactant.
• the reactor used for the active process was a stirred autoclave
• the (TCHC) 19 thermal catalytic hydroconversion studies were performed in 20 an unstirred reactor having a length to diameter ratio of 21 20.
• the Maya feedstocks used in both studies were virtually 22 identical with the possible exception of a small difference 23 in the 1000°F+ content.
• TCHC thermal catalytic hydroconversion 25 process
• Table VIII shows the capability of 2 the process of the present invention to remove metals from 3 heavy oils more efficaciously than the other process.
• the 4 advantage in this superior metals removal is improved 5 operations of the catalytic hydroprocessing second-stage due 06 to increased catalyst life.
• the demetalation is 07 realized at lower thermal severity and consequently lower 08 destabilization of the feed prior to catalytic go hydroprocessing.
• . process of the present invention provides demetalation at ⁇ lower levels of conversion than the inactive slurry catalyst _. ⁇ process. Lower conversion leads to lower destabilization of 17 the feed prior to catalytic hydroprocessing. The less
• hydroprocessing units is limited by metals or coke deposited
• the life of these catalysts can be increased by 28 removing a portion of the metals and coke precursors.
• the 29 demetalation and coke precursor removal can be achieved with 30 an active slurry catalyst in which some of the metals are 31 deposited on said slurry catalyst prior to contacting the 32 heavy feed with the fixed bed or ebullating bed catalyst.
• the demetalation can be achieved by the slurry 34 01 catalyst within the fixed bed or ebullating bed 02 hydroprocessing unit.
• the slurry catalyst was prepared by sulfiding an aqueous
• the fixed bed reactors were charged with a 30 graded catalyst system: 16.7 volume percent of Catalyst A 31 containing 1.5% cobalt, 6% molybdenum, and 0.8% phosphorous 32 on alumina; 16.7 volume percent of Catalyst B containing 33 1% cobalt, 3% molybdenum, and 0.4% phosphorous on alumina; 34 Q - and 66.6% volume percent of Catalyst C containing 3% nickel,
• the flow 03 direction was upflow with Catalyst A placed at the bottom of 04 the reactor.
• Catalyst B was placed above Catalyst A, and 05 Catalyst C was placed above Catalyst B.
• the 06 catalysts were sulfided.
• the slurry reactor was a one-liter 07 autoclave equipped with a turbine to insure good mixing 08 between the liquid, gas, and catalyst. Flow of the gas, 09 oil, and catalyst was upward.

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• 1991
  • 1991-04-26 KR KR1019920700497A patent/KR920702252A/ko not_active Withdrawn
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  • 1991-04-26 EP EP19910913933 patent/EP0491932A4/en not_active Withdrawn
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  • 1991-04-26 CA CA002066453A patent/CA2066453A1/fr not_active Abandoned
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