US3422163A - Recovery of aromatics from multiple hydrocarbon streams - Google Patents

Recovery of aromatics from multiple hydrocarbon streams Download PDF

Info

Publication number
US3422163A
US3422163A US499972A US3422163DA US3422163A US 3422163 A US3422163 A US 3422163A US 499972 A US499972 A US 499972A US 3422163D A US3422163D A US 3422163DA US 3422163 A US3422163 A US 3422163A
Authority
US
United States
Prior art keywords
solvent
aromatics
feed
phase
extractor
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US499972A
Other languages
English (en)
Inventor
George F Asselin
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Universal Oil Products Co
Original Assignee
Universal Oil Products Co
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Universal Oil Products Co filed Critical Universal Oil Products Co
Application granted granted Critical
Publication of US3422163A publication Critical patent/US3422163A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

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
    • C10G21/00—Refining of hydrocarbon oils, in the absence of hydrogen, by extraction with selective solvents
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D11/00—Solvent extraction
    • B01D11/04—Solvent extraction of solutions which are liquid
    • B01D11/0488—Flow sheets

Definitions

  • This invention relates to a process for the separation of hydrocarbons from at least two hydrocarbon mixtures with the aid of a selective solvent for the purpose of separating and recovering the aromatic hydrocarbon components of the mixtures.
  • the process of the present invention serves to segregate the particular species of aromatic hydrocarbons, such as benzene, toluene and/or C8 aromatics from other classes of hydrocarbons that are normally contained in petroleum distillates, and utilizes a solvent which may be indefinitely recycled in the system, yields the desired hydrocarbon product in a state of high purity and separates the same substantially in its entirety from the feed stocks charged to the process.
  • the present invention is concerned with an improvement in the type of separation process wherein at least two mixtures of various classes of hydrocarbons, the nonaromatic components of which in one mixture are more readily stripped out of a solvent-aromatic mixture in an extractive stripper than the non-aromatic components of the other mixture, ⁇ are introduced into an extraction zone at an intermediate pointthereof and are countercurrently contacted therein with a solvent selective for aromatic hydrocarbons, a lean solvent is introduced into an upper point in the extraction zone, a rainate phase comprising substantially all of the nonaromatic hydrocarbons in the feed stocks is removed from the upper end portion of the extraction zone, an extract comprising the aromatic components of the feed stocks dissolved in the solvent phase is removed from the lower end portion of the extraction zone and the aromatic solute is subsequently recovered by extractive stripping and fractionation of the extract phase.
  • said one mixture containing non-aromatic components having a tendency to be more readily stripped out of the extract phase in an extractive stripper than the non-aromatic components in the other mixture is introduced into the extraction zone at a point closer to the withdrawal of extract from the zone than the other mixture in order to improve the aromatics purity and/ or yield as described hereinafter.
  • this invention relates to a process for the separation and recovery of aromatic hydrocarbons from at least two hydrocarbon containing fluids having a solvent extraction step to form an extract phase and a raffinate phase and an extractive distillation step to remove non-aromatic hydrocarbons from the 3,422,163 Patented Jan.
  • extract phase in which a substantial portion of the nonaromatic components of the first fluid have an increased volatility in the extractive distillation step when compared to a substantial portion of the non-aromatic components of the other fluid which comprises: introducing a lean solvent into an upper intermediate point in the height of an extraction zone; introducing the other fluid into a middle intermediate point in the height of an extraction zone; introducing the first fluid into .a lower intermediate point in the height of an extraction zone; countercurrently contacting the solvent with the fluids in the extraction Zone; removing a hydrocarbon reaflinate phase consisting essentially of non-aromatics yfrom an upper point of said zone; removing a solvent extract phase enriched in aromatics content from a lower point of said Zone; introducing the extract phase into an extractive distillation column and stripping essentially all of the non-aromatic hydrocarbons from the extract phase; and separating the aromatics from the solvent.
  • Solvent extraction processes for the recovery of aromatic hydrocarbons from hydrocarbon mixtures have been known for many years. This is usually accomplished by methods such as extractive distillation or alternately by countercurrently contacting the feed with a solvent selective for aromatics in the liquid phase within an extractor.
  • the present process relates to both of these methods.
  • the solvents described hereinafter exhibit an increasing solubility selectivity for hydrocarbons as the hydrocarbons degree of unsaturation increases.
  • the selectivity of a solvent is -greater for aromatics than naphthenes, greater for naphthenes than parai'lins, etc.
  • a solvent exhibits an increasing solubility selectivity for a given class of hydrocarbons as the number of carbon atoms per molecule decreases.
  • the stripper is able to remove the non-aromatic components of the extract phase because the presence of the solvent in the stripper has less effect on the boiling point of the non-aromatic components dissolved in the solvent than it does on the aromatic compounds also dissolved in the solvent.
  • the solvent tends to retain in solution the more soluble aromatic component even at temperatures considerably above the normal boiling point of the aromatics alone. This effect can be further emphasized by introducing additional lean solvent into the stripper along with the extract phase.
  • the amount of suppression of boiling point of the aromatics is limited and when processing charge stocks of wide boiling ranges it becomes impossible to vaporize the heavy non-aromatics without also vaporizing the light aromatics.
  • the feed may be of such a narrow boiling range that a backwash stream is not very effective.
  • a backwash stream is not very effective.
  • the present invention is employed to produce just as -good results as could be obtained by employing a backwash stream. It is also possible to combine the present invention along with the backwash step to further improve the process for the production of aromatics.
  • feed ⁇ #l is introduced into ow conduit where it picks up a reux stream from a source described hereinafter and flows into a lower intermediate point in extraction zone 3.
  • feed ⁇ .iii-'1 is introduced into extractor 3 from about 1A; to about 1/12 of the way along its height from the bottorn.
  • Feed #2 is introduced into flow conduit 4 where it ows into a middle intermediate point in extractor 3.
  • feed #2 is introduced into extractor 3 from about 1A; to about 1/10 of the way along its height from the bottom.
  • the distance between the lower intermediate point and the middle intermediate point is preferably at least 4% of the total height of extractor 3.
  • Lean solvent from a source described hereinafter is introduced into an upper intermediate point through flow conduit 6 whereupon the solvent ows downflow through extractor 3 and countercurrently contacts the feeds which flow upow through extractor 3.
  • the extractor contains contacting means such as bafe plates, sieve decks, rotary discs, packing, etc., to eiciently intermix the immiscible solvent and feed phases.
  • the extractor is maintained at an elevated temperature and pressure sufficient to maintain the solvent and the feeds in the liquid phase. Since the solvent has a selectivity for the aromatics and the solvent is immiscible with the feeds, aromatics will preferentially dissolve into the solvent phase.
  • the aromatics concentration therein gradually increases while as the feed hydrocarbon phase passes uptow through the extractor due to its lower density (than the solvent phase) the aromatics concentration therein gradually decreases.
  • the hydrocarbon phase passes the upper intermediate point, it contains essentially no aromatics.
  • This material is called the raffinate phase and is removed from extractor 3 through an upper point where it passes into flow conduit 7.
  • the raflinate may be fractionated and/ or water-washed to remove small quantities of dissolved solvent.
  • the extract phase comprising solvent, substantially-all the aromatics in the Ifeeds, and some non-aromatics is removed from a lower point in extractor 3 where it passes into ow conduit 8.
  • the non-aromatics present in the extract phase are derived from the non-aromatics present in the material flowing in flow conduit 5, which is the recycle stream in flow conduit 15 and feed #1.
  • Feed #1 contains non-aromatics which are more readily vaporized in the extractive stripper described hereinafter than the non-aromatics present in feed .#2.
  • a feed #l having the non-aromatic portion rich in paraftins and a feed #2 having the non-aromatics portion rich in naphthenes are employed as feeds and are introduced into extractor 3 as described hereinabove.
  • Paraflins are less selectively absorbed by the solvent phase :but since their concentration is higher in the hydrocarbon phase between ow conduits 4 and 5 in the height of the extractor, there is suflicient driving force to allow the paraflins to displace the naphthenes from the solvent phase to the hydrocarbon phase. Therefore, the extract phase leaving extractor 3 through ow conduit 8 contains predominantly parafns as the non-aromatic portion.
  • feed #1 is lighter in molecular weight and lower in boiling point than feed '#2
  • light nonaromatic hydrocarbons are doubly effective in displacing the 4heavier non-aromatics since they are more selectively absorbed by the solvent phase and are present in high concentrations in the hydrocarbon phase between flow conduits 4 and 5 (relative to the heavy non-aromatics). Therefore, the extract phase leaving extractor 3 through flow conduit 8 contains predominantly light non-aromatics as the Anon-aromatic portion.
  • This latter example can be economically and efficiently carried out even with a single feed stock by introducing said feed into a splitter column, removing a light feed stock portion overhead and introducing it into the lower inter-mediate point in the extraction zone while removing a heavy feed stock portion from the bottom and introducing it into the middle intermediate point.
  • the important point in all these cases is that the feed whose non-aromatic components are more volatile in an extractive stripper is introduced into a point closer to the extract withdrawal point than another feed whose non-aromatic components are less volatile in the extractive stripper.
  • the extract phase leaves extractor 3 through ow conduit ⁇ f5 where it mixes ⁇ with additional lean solvent owing in ow conduit 9, if desired, and the total mixture flows through flow conduit 10' and into extractive stripper 11.
  • the stripper is operated at elevated temperatures and intermediate pressures (relative to the extractor pressure) in order to remove substantially all of the nonaromatics, some of the water and aromatics and a small amount of the solvent overhead.
  • This overhead stream is removed from stripper 11 through flow conduit 12 where it passes through condenser 13 and into overhead receiver 14.
  • the overhead stream is condensed and separated into two phases, one a water-solvent phase and the other a hydrocarbon phase. This hydrocarbon phase is withdrawn from receiver 14 through flow conduit 15 Where it is recycled to ow conduit 5 and eventually into extractor 3.
  • a bottoms stream consisting essentially of aromatic hydrocarbons and solve-nt is withdrawn from the bottom of stripepr 11 and through fiow conduit 18 where a portion thereof ows through flow conduit 19, reboiler heater 20 and return to stripper 1t1. The remaining bottoms portion ows through ow conduit 21 and into solvent recovery column 22.
  • Column 22 is preferably operated at low pressures (relative to the extractor pressure) and elevated temperatures to separate the solvent from the aromatics.
  • the aromatics andsome of the water are removed from column 22 as a vapor and pass through ow conduit 23, condenser 24 and into receiver 25.
  • the overhead is separated into a hydrocarbon phase comprising aromatics and a Water phase.
  • the aromatics are withdrawn from receiver 25 through ow conduit 26 where a portion thereof ret-urns to column 22 through flow conduit 27 as reflux -while the' remaining portion of aromatics is withdrawn through flow conduit 28 as net product.
  • the net product is sent to a series of fractionators to recover the individual aromatics as substantially pure components such as benzene, toluene, ortho-xylene, ethylbenzene, etc.
  • a bottom stream consisting essentially of lean solvent is withdrawn from column 22 through flow conduit 31 where a portion thereof flows through flow conduit 32, reboiler heater 33 and returns to column 22.
  • the remaining bottoms portion iiows through flow conduit 34 where a fraction thereof flows into flow conduit 6 and into the upper-intermediate point of extractor 3 while the other fraction ows into ow conduit 9 where it mixes with extract phase before entering stripper 11.
  • a small amount of decomposition of solvent and other sludge forming reactions may occur in the process and it is desirable to remove a small slipstream of lean solvent from flow conduit 34 through ow conduit 35 and regenerate the solvent in equipment not shown in order to prevent the build up of sludge.
  • the regeneration preferably is done by rerunning the solvent and thereafter the regenerated solvent is returned to flow conduit 34 by means of ⁇ flow conduit 36.
  • suicient water is added to the lean solvent in equipment not shown to adjust the Water content of the lean solvent to the desired level. This is convenientlyly done by introducing the water into flow conduit 36.
  • Suitable feed stocks for the process of this invention comprises fluid hydrocarbon mixtures containing at least 6 carbon atoms per molecule.
  • Feed #l is preferably selected in relation to feed #2 in order to attain the desired non-aromatic displacement referred to hereinbefore.
  • a preferable combination is for feed #1 to be debutanized or 1depentanized reformate (which is lean in napthenes) and for feed #2 to be a debutanized or depentanized hydrotreated pyrolysis liquid (which is rich in naphthenes).
  • Another preferable combination is for feed #1 to be a lighter fluid hydrocarbon mixture such as in the C5 to C7 range and for feed #2 to be a heavier fluid hydrocarbon mixture such as in the C7 to C10 range. It is readily apparent that many other suitable pairings of feed stocks may be used to attain the eicient stripping referred to hereinbefore and it is intended that these pairings be included within the scope of this invention.
  • solvents may advantageously be ernployed in the process of this invention providing they possess a solubility selectivity for aromatics over more saturated hydrocarbons.
  • Preferable solvents include the glycols, sulfolanes, sulfoxides, pyrrolidones, etc.
  • Especially preferable solvents include diethylene glycol, various polyethylene glycols, dipropylene glycol, various polypropylene glycols, dimethyl sulfoxide, N-methyl pyrrolidone, saturated sulfolane (C4H8SO2), Sulfolene (CaHsSOz) etc.
  • the present solvents contain a small amount of water dissolved therein (from about 0.5% to about 20%) to increase the selectivity of the overall solvent phase for aromatic hydrocarbons over non-aromatic hydrocarbons without reducing substantially the solubility of the solvent phase for aromatic hydrocarbons over non-aromatic hydrocarbons.
  • the presence of water in the solvent composition furthermore provides a relatively volatile material therein which is distilled from the extract phase in the extractive stripper 'which aids in vaporizing the last traces of non-aromatic hydrocarbon from the extract phase by steam stripping.
  • water is added thereto in concentrations of from about 0.1% to about 20% by weight.
  • the extractor is operated at elevated temperatures and at a sufficiently elevated pressure to maintain the feed stocks, recycle stream and solvent in the liquidphase.
  • Suitable temperatures are within the range of from F. to about 400 F. and preferably from about 150l F. to about 300 IF.
  • Suitable pressures are withinthe range of from about atmospheric pressure up to about ⁇ 400 p.s.i.g. and preferably from about 50 p.s.i.g. to about 150 p.s.i.g.
  • Suitable contacting means in the extractor vessel to efficiently contact the solvent phase with the hydrocarbon phase include sieve decks, baffles, rotary discs, packing, etc.
  • the extractive stripper is operated at moderate pressures and suiciently high reboiler temperatures to vaporize all the non-aromatic hydrocarbons, and some of the aromatics, water and solvent. .
  • the stripper is preferably operated at lower pressures than the extractor, preferably from a slight vacuum up to about p.s.i.g.
  • the reboiler temperature is dependent upon the composition of the feed and the solvent.
  • the solvent recovery column is preferably operated at lower pressures than the stripper and sufficiently high temperatures to vaporize the aromatic hydrocarbons without thermally decomposing the solvent.
  • moderate to high vacuum must be employed in order to maintain a sufficiently low reboiler temperature to avoid thermal decomposition while permitting vaporization of the aromatics.
  • Pressures may be from about 100 mm. mercury absolute to moderate superatmospheric pressures in the order of 20 p.s.i.g.
  • the apparatus employed in the process of this invention may be any conventional convenient type known to those skilled in the art.
  • the drawing does not show all the pumps, tanks, heat exchangers, valves, bypasses, vents, preheaters, coolers, control valves, means for actuating control valves and other auxiliaries that may be necessary for the proper operation of the process but the inclusion of which will be evident to those skilled in the art.
  • a rst feed consisting of a reformate in the C6-C8 carbon number range is introduced into flow conduit 5 (see the drawing) at a rate of 100 moles/hr. whereupon it flows into the lower intermediate point (Ma of the height from the bottom) in extractor 3.
  • the reformate contains approximately 50 volume percent aromatics, 46 volume percent paraiiins and 4 volume percent napthenes.
  • a second feed consisting of a hydrotreated pyrolysis gasoline in the C6-C8 carbon number range is introduced into flow conduit 4 at a rate of 1000 moles/hr. whereupon it flows into the middle intermediate point in extractor 3 (1A of the height of the extractor).
  • the pyrolysis gasoline 'contains approximately 65 volume percent aromatics, 30 volume percent naphthenes and 5 volume percent paraflins.
  • Saturated sulfolane (C4H8SO2) is employed as the organic solvent for this example.
  • Lean solvent consisting of sulfolane containing about 5% (mole) water is introduced into the upper intermediate point in extractor 3 through flow conduit 6 at a rate of 600 moles/hr.
  • a recycle stream owing through ow conduit 15 is introduced into extractor 3 at a rate of 140 moles/hr.
  • the extractor is maintained at a pressure of 100 p.s.i.g. and a temperature of 200 F.
  • a raflinate product is withdrawn from the upper point in extractor 3 through ilow conduit 7 at a rate of 86 moles/hr.
  • An extract stream is withdrawn from the lower point in extractor 3 through ow conduit 8 at a rate of 854 moles/hr. where it contacts an additional 200 moles/hr. of lean solvent flowing through flow conduit 9.
  • the total mixture is introduced into ow conduit 10 where it flows into stripper 11.
  • Stripper 11 is operated at a top pressure of 13 p.s.i.g., a top temperature of about 225 F. and a bottom temperature of about 350 F. These conditions allow essentially complete vaporization of the non-aromatics in stripper 11.
  • the overhead vapors from stripper 11 are condensed and settle into receiver 14.
  • the hydrocarbon phase separates therein and is recycled through flow conduit 15 at a rate of about 140 moles/hr.
  • the stripper bottoms consisting essentially of aromatic hydrocarbons, organic solvent and a small amount of water is introduced into solvent recovery column 22.
  • Column 22 is operated at a top pressure of about 200 mm. mercury absolute, a top temperature of about 150 F. and a bottom temperature of about 350 F.
  • the aromatics are removed overhead in column 22 and the organic solvent is removed out the bottom of column 22. Sufficient water is added to this organic solvent to bring the water concentration back to about 5%.
  • the aromatics overhead is fractionated into the individual compounds, its purity is analyzed and a material balance is calculated.
  • the purity of the benzene and toluene is at least nitration grade and the purity of the C8 aromatics is above 99.5%
  • the recovery of benzene is about 99%, the recovery oi toluene is above 98% and the recovery of C8 aromatics is above 95%. It is expected that had the feeds been introduced into the same point in the extractor the purity of the aromatics at the same operating conditions would have been lower.
  • the process of claim 1 further characterized in that the solvent is selected from the group consisting of the polyethylene glycols and the polypropylene glycols.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Engineering & Computer Science (AREA)
  • General Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
  • Production Of Liquid Hydrocarbon Mixture For Refining Petroleum (AREA)
US499972A 1965-10-21 1965-10-21 Recovery of aromatics from multiple hydrocarbon streams Expired - Lifetime US3422163A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US49997265A 1965-10-21 1965-10-21

Publications (1)

Publication Number Publication Date
US3422163A true US3422163A (en) 1969-01-14

Family

ID=23987528

Family Applications (1)

Application Number Title Priority Date Filing Date
US499972A Expired - Lifetime US3422163A (en) 1965-10-21 1965-10-21 Recovery of aromatics from multiple hydrocarbon streams

Country Status (10)

Country Link
US (1) US3422163A (nl)
AT (1) AT276351B (nl)
BR (1) BR6683885D0 (nl)
DE (1) DE1545414A1 (nl)
DK (1) DK133436B (nl)
ES (1) ES332482A1 (nl)
GB (1) GB1154603A (nl)
NL (1) NL149846B (nl)
SE (1) SE343316B (nl)
YU (1) YU31913B (nl)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3764522A (en) * 1971-12-20 1973-10-09 Sun Oil Co Pennsylvania Solvent extraction of c{11 {13 c{11 {11 aromatic hydrocarbons
US3779904A (en) * 1971-12-21 1973-12-18 Union Carbide Corp Process for the separation of aromatic hydrocarbons from a mixed hydrocarbon feedstock
FR2485562A1 (fr) * 1980-06-27 1981-12-31 Texaco Development Corp Procede de raffinage de fractions d'huiles lubrifiantes a forte teneur en aromatiques
US4421607A (en) * 1982-02-02 1983-12-20 Nippon Zeon Co. Ltd. Process for extractive distillation of plural hydrocarbon mixtures
US4519901A (en) * 1981-12-18 1985-05-28 Exxon Research & Engineering Co. Extractive separation process

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2365898A (en) * 1943-10-19 1944-12-26 Shell Dev Solvent extraction process
US2407820A (en) * 1943-03-23 1946-09-17 Shell Dev Process for separating aromatic hydrocarbons
US2770663A (en) * 1952-07-30 1956-11-13 Universal Oil Prod Co Solvent extraction of hydrocarbons
US2886610A (en) * 1954-04-28 1959-05-12 American Oil Co Solvent recovery system
US3037062A (en) * 1956-05-16 1962-05-29 Universal Oil Prod Co Selective solvent extraction process for the separation of mixtures of aromatic and non-aromatic hydrocarbons
US3200165A (en) * 1961-07-08 1965-08-10 Metallgesellschaft Ag Recovery of aromatic and olefinic hydrocarbons

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2407820A (en) * 1943-03-23 1946-09-17 Shell Dev Process for separating aromatic hydrocarbons
US2365898A (en) * 1943-10-19 1944-12-26 Shell Dev Solvent extraction process
US2770663A (en) * 1952-07-30 1956-11-13 Universal Oil Prod Co Solvent extraction of hydrocarbons
US2886610A (en) * 1954-04-28 1959-05-12 American Oil Co Solvent recovery system
US3037062A (en) * 1956-05-16 1962-05-29 Universal Oil Prod Co Selective solvent extraction process for the separation of mixtures of aromatic and non-aromatic hydrocarbons
US3200165A (en) * 1961-07-08 1965-08-10 Metallgesellschaft Ag Recovery of aromatic and olefinic hydrocarbons

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3764522A (en) * 1971-12-20 1973-10-09 Sun Oil Co Pennsylvania Solvent extraction of c{11 {13 c{11 {11 aromatic hydrocarbons
US3779904A (en) * 1971-12-21 1973-12-18 Union Carbide Corp Process for the separation of aromatic hydrocarbons from a mixed hydrocarbon feedstock
FR2485562A1 (fr) * 1980-06-27 1981-12-31 Texaco Development Corp Procede de raffinage de fractions d'huiles lubrifiantes a forte teneur en aromatiques
US4519901A (en) * 1981-12-18 1985-05-28 Exxon Research & Engineering Co. Extractive separation process
US4421607A (en) * 1982-02-02 1983-12-20 Nippon Zeon Co. Ltd. Process for extractive distillation of plural hydrocarbon mixtures

Also Published As

Publication number Publication date
DK133436C (nl) 1976-10-25
YU197266A (en) 1973-08-31
DE1545414A1 (de) 1970-01-29
GB1154603A (en) 1969-06-11
NL149846B (nl) 1976-06-15
SE343316B (sv) 1972-03-06
AT276351B (de) 1969-11-25
DK133436B (da) 1976-05-17
ES332482A1 (es) 1967-08-01
NL6614900A (nl) 1967-04-24
YU31913B (en) 1974-02-28
BR6683885D0 (pt) 1973-08-28

Similar Documents

Publication Publication Date Title
US3723256A (en) Aromatic hydrocarbon recovery by extractive distillation, extraction and plural distillations
US4053369A (en) Extractive distillation
US3361664A (en) Flashing and extractively distilling an extract
US3114783A (en) Separation of aromatics from hydrocarbon streams
CA2134849A1 (en) Process to recover benzene from mixed hydrocarbons
WO1997044298A1 (en) Recovery of styrene from pyrolysis gasoline by extractive distillation
US2770663A (en) Solvent extraction of hydrocarbons
US6781026B2 (en) Aromatics purification from petroleum streams
US4401517A (en) Vapor-liquid extractive distillation with dialkyl sulfone/water combination
EP0033512B1 (en) Separation of aromatic hydrocarbons from petroleum fractions
GB1582146A (en) Polar hydrocarbon extraction with solvent recovery and regeneration
US3642614A (en) Reduction of soluble contaminants in lean solvent
US3844902A (en) Combination of extractive distillation and liquid extraction process for separation of a hydrocarbon feed mixture
US3590092A (en) Method for aromatic hydrocarbon recovery
US3763037A (en) Aromatic hydrocarbon
US3037062A (en) Selective solvent extraction process for the separation of mixtures of aromatic and non-aromatic hydrocarbons
US5073669A (en) Method for aromatic hydrocarbon recovery
US3435087A (en) Recovery of aromatics
US3422163A (en) Recovery of aromatics from multiple hydrocarbon streams
US3544453A (en) Process for the extraction and recovery of aromatic hydrocarbons
US4083772A (en) Aromatic hydrocarbon separation process
US3249532A (en) Solvent extraction of aromatics
US3396101A (en) Solvent extraction of highly aromatic charge stocks
US2848387A (en) Separation of aromatic and nonaromatic hydrocarbons
US2803685A (en) Process for the extraction and recovery of aromatic hydrocarbons from hydrocarbon mixtures