US3714033A - Process for the separation of aromatic hydrocarbons from a mixed hydrocarbon feedstock - Google Patents

Process for the separation of aromatic hydrocarbons from a mixed hydrocarbon feedstock Download PDF

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US3714033A
US3714033A US00180996A US3714033DA US3714033A US 3714033 A US3714033 A US 3714033A US 00180996 A US00180996 A US 00180996A US 3714033D A US3714033D A US 3714033DA US 3714033 A US3714033 A US 3714033A
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water
phase
percent
aromatic hydrocarbons
solvent
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G Somekh
D Kubek
A Kosseim
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Katalistiks International Inc
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Union Carbide Corp
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    • 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
    • C10G21/28—Recovery of used solvent
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C7/00—Purification; Separation; Use of additives
    • C07C7/04—Purification; Separation; Use of additives by distillation
    • C07C7/05—Purification; Separation; Use of additives by distillation with the aid of auxiliary compounds
    • C07C7/08—Purification; Separation; Use of additives by distillation with the aid of auxiliary compounds by extractive distillation
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C7/00—Purification; Separation; Use of additives
    • C07C7/10—Purification; Separation; Use of additives by extraction, i.e. purification or separation of liquid hydrocarbons with the aid of liquids

Definitions

  • step (g) Contacting the water phase of step (d) with an aromatic hydrocarbons stream containing at least 95 percent aromatic hydrocarbons, the amount of said stream being in the range of about 0.1 percent to about 5 percent by weight of the total aromatic hydrocarbons in the feedstock to form an aromatic hydrocarbons phase and a water phase;
  • step (i) Recycling the reflux hydrocarbons phase of the overhead distillate and the bottoms of step (b) to the extraction zone to provide reflux hydrocarbons and mixture of water and solvent, respectively, for step (a);
  • step (j) Recovering the aromatic hydrocarbons phase of step (f) and the aliphatic hydrocarbons phase of step (d).
  • This invention relates to an improvement in a process for the separation of aromatic hydrocarbons from a mixed ice hydrocarbon feedstock and, more particularly, to the recovery of high purity aromatic hydrocarbons in high yields while making eflicient use of process components.
  • Improved process economics can be translated into, among other things, the use of less apparatus, the lowering of heating requirements, and the more effective use of process components as aids in the separation process.
  • these processes use two separate water circuits.
  • One circuit is the stripping water circuit for removing aromatics from the glycol in the stripper and the other is a water wash circuit. Both water streams are revaporized in these processes.
  • the make-up of the water wash circuit is such that the water first washes raflinate and then is distilled.
  • distillation does not remove all dissolved and entrained aliphatics from the water and yet it is then used to wash glycol from the aromatics product resulting in decreased product purity.
  • stripping water circuit stripping water from the reflux decanter also contains some aliphatics.
  • the use of two or more distillation columns is the rule rather than the exception in this type of system.
  • An object of this invention is to provide an improvement in a process for the separation of aromatic hydrocarbons from a mixed hydrocarbon feedstock in which a solvent-water composition is utilized whereby aromatics are recovered in high purity using a minimum of apparatus and heat and making more effective use of process components.
  • high purity aromatic hydrocarbons are effectively recovered using minimal apparatus and heat by a continuous solvent extraction-steam distillation process for the recovery of aromatic hydrocarbons having boiling points in the range of about C. to about C. from a feedstock containing aliphatic hydrocarbons and said aromatic hydrocarbons comprising the following steps:
  • step (g) contacting the water phase of step (d) with an aromatic hydrocarbons stream containing at least 95 percent aromatic hydrocarbons, the amount of said stream being in the range of about 0.1 percent to about 5 percent by weight of the total aromatic hydrocarbons in the feedstock to form an aromatic hydrocarbons phase and a water phase;
  • step (i) recycling the reflux hydrocarbons phase of the overhead distillate and the bottoms of step (b) to the extraction zone to provide reflux hydrocarbons and mixture of water and solvent, respectively, for step (a);
  • step (j) recovering the aromatic hydrocarbons phase of step (f) and the aliphatic hydrocarbons phase of step (d).
  • BTX DESCRIPTTON OF THE PREFERRED EMBODIMENT
  • hydrocarbon feedstocks such as reformed gasolines; coke oven light oils; cracked gasolines; and dripolenes, which, after hydrogenation, can contain as much as 70 to 98 percent BTX.
  • feedstocks also contain both aliphatic and cycloaliphatic hydrocarbons (herein referred to collectively as aliphatic hydrocarbons).
  • hydrocarbons with boiling points ranging from 25 C. to 175 C. including straightchain and branched-chain paraffins and naphthenes, such as n-heptane, isooctane, and methyl cyclohexane, and aromatics such as BTX.
  • the BTX fraction can include benzene, toluene, the C aromatics including ortho-xylene, meta-xylene, paraxylene, and ethyl benzene, and C aromatics, which, if
  • the solvents used in subject process are, as described above, water-miscible organic liquids (at process temperatures) having a boiling point of at least about 200 C. and having a decomposition temperature of at least about 225 C.
  • water-miscible includes those solvents which are completely miscible over a wide range of temperatures and those solvents which have a high partial miscibility at room temperature since the latter are usually completely miscible at process temperatures.
  • the solvents are also polar and are generally comprised of carbon, hydrogen and oxygen with some exceptions.
  • solvents which may be used in the process of this invention are dipropylene glycol, tripropylene glycol, dibutylene glycol, tributylene glycol, ethylene glycol, diethylene glycol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, sulfolane, N- methyl pyrrolidone, triethylene glycol, tetraethylene glycol, ethylene glycol diethyl ether, propylene glycol monoethyl ether, pentaethylene glycol, hexamethylene glycol, and mixtures thereof.
  • the preferred group of solvents is the polyalkylene glycols and the preferred solvent is tetraethylene glycol.
  • Additional solvents which may be used alone or together, or with the aforementioned solvents are amides such as formamide, acetamide, dimethylformamide, diethylformamide, and dimethylacetamide; amines such as diethylenetriamine and triethylenetetramine; alkanolamines such as monoethanolamine, diethanolamine, and triethanolamine; nitriles such as beta,beta -oxydipropionitrile and beta,beta -thiodipropionitrile; phenol and the cresols; the methyl sulfolanes; sulfoxides such as dimethyl sulfoxide and diethyl sulfoxide; lactones such as gammapropiolactone and gamma-butyrolactone.
  • amides such as formamide, acetamide, dimethylformamide, diethylformamide, and dimethylacetamide
  • amines such as diethylenetriamine and triethylenetetramine
  • the apparatus used in the process both for the main extraction and the distillation is conventional, e.g., an extraction column of the multistage reciprocating type containing a plurality of perforated plates centrally mounted on a vertical shaft driven by a motor in an oscillatory manner can be used as well as columns containing pumps with settling zones, sieve trays with upcomers, or even a hollow tube while the distillation can be conducted in a packed bubble plate fractionating column. Counter-current flows are utilized in both extraction and distillation columns.
  • Heat exchangers, decanters, reservoir and solvent regenerator are also conventional as well as various extractors other than the main extractor. These other extractors are preferably single stage mixer-settlers, but can be any of the well known types.
  • the solvent is used as an aqueous solution thereof containing water in an amount of about 1 percent to about 8 percent by weight based on the weight of the solvent and preferably containing water in an amount of about 2 percent to about 5 percent by weight.
  • This aqueous solution is referred to hereafter in some instances as a solvent-water mixture.
  • the ratio of solvent (exclusive of water) to feedstock in the extractor is in the range of about 4 to about 8 parts by weight of solvent to one part by weight of feedstock.
  • This broad range can be expanded upon where nonpreferred solvents are used.
  • a broad range of about 3 to about 12 parts by weight of solvent to one part by weight of feedstock and a preferred range of about 5 parts to about 7 parts of solvent per part of feedstock can be used successfully for the solvent of preference and other like solvents.
  • the ratio is selected by the technician based on experience with the particular feedstock and depends in part upon whether high recovery or high purity is being emphasized, although the instant process will improve purity in any case.
  • the reflux to the extraction zone is generally made up of about 20 percent to about 50 percent by weight aliphatics having from to 7 carbon atoms and about 50 percent to about 80 percent by weight aromatics, both based on the total weight of the reflux.
  • the ratio of reflux to feedstock in the extraction zone is, generally, maintained in the range of about 0.5 to about 1.5 parts by weight of reflux to one part by weight of feedstock and preferably about 0.5 to about 1.0 part by weight of reflux to one part by weight of feedstock, but, again, is selected by the technician just as the ratio of solvent to feedstock.
  • the reflux aliphatics pass into the extract rather than being taken overhead with the raflinate and are recycled to the extractor from the reflux decanter as will be seen hereinafter.
  • the temperature in the extraction zone is maintained in the range of about 100 C. to about 200 C. and is preferably in the range of about 125 C. to about 150 C., especially for the solvent preference.
  • the pressure in the extraction zone is maintained in the range of about 75 p.s.i.g. to about 20 p.s.i.g. As is well known in the art, however, one selected pressure is not maintained throughout the extraction zone, but, rather, a high pressure within the stated range is present at the bottom of the zone and a low pressure again within the stated range is present at the top of the zone with an intermediate pressure in the middle of the zone.
  • the pressures in the zone depend on the design of the equipment and the temperature, both of which are adjusted to maintain the pressure within the stated range.
  • the temperature at the top of the distillation zone which, in terms of the apparatus used, may be referred to as a distillation column or stripper, is at the boiling point of the mixture of aromatics present in the zone while the temperature at the bottom of the stripper is generally in the range of about 135 C. to about 200 C.
  • the pressure at the top of the stripper, an upper flash zone in this case, is in the range of about 20 p.s.i.g. to about 35 p.s.i.g.
  • the pressure is in the range of about p.s.i.g. to about p.s.i.g. and is about 10 or 15 p.s.i.g. lower than the pressure in the upper flash zone.
  • the pressure in the rest of the distillation zone is maintained in the range of about 15 p.s.i.g. to about p.s.i.g. with some variation throughout the zone.
  • the steam brought into the bottom of the distillation zone enters at a temperature of about 100 C. to about 150 C. and is under a pressure of about 15 p.s.i.g. to about 25 p.s.i.g.
  • the total water present in the distillation column is essentially in vapor form and is generally in the range of about 0.1 part to about 0.5 part by weight of water to one part by weight of aromatics in the zone and preferably in the range of about 0.1 part to about 0.3 part by weight of water to one part by weight of aromatics.
  • the water used for the steam may be called stripping water. A small amount of water is present in liquid form in the distillation zone dissolved in the solvent.
  • the feedstock is introduced through line 1 into heat exchanger 2 where it is preheated to a temperature in the range of about 50 C. to about 100 C. It then continues through line 1 to enter extractor 3 at about the middle tray thereof.
  • An aqueous solvent solution having a temperature in the range of about 125 C. to about 175 C. enters at the top tray of extractor 3 through line 4 and percolates down the column removing aromatics from the feedstock.
  • the rafi'lnate leaves the top of the column through heat exchanger 2 where it is used to preheat the feedstock and is cooled in turn to a temperature in the range of 75 C. to about 125 C.
  • the ratfinate comprises about 95 percent to about 98 percent by weight aliphatics, about 1 percent to about 3 percent by weight dissolved and entrained solvent, and about 0 percent to about 3 percent by weight aromatics.
  • the raifinate then passes through cooler 6 where it is further cooled to about 25 C. to about 50 C. and proceeds along line 5 to decanter 7 where it separates into two phases, an aliphatic hydrocarbons phase and a solvent phase, the solvent being contaminated with aliphatics.
  • phase is named after its main component, which is present in the phase in an amount of at least 50 percent by weight and, in most cases, in an amount of at least percent by weight.
  • the aliphatic hydrocarbons phase which can still be referred to as the raflinate, now contains about 96 percent to about 99 percent by weight aliphatics, about 0 percent to about 1 percent by weight dissolved and entrained solvent, and about 0 percent to about 3 percent by weight aromatics.
  • the solvent phase contains about 90 percent to about 96 percent by weight solvent, about 2 percent to about 5 percent by weight water, and about 2 percent to about 4 percent by weight aliphatics.
  • raflinate continues overhead through line 5 into raffinate extractor 8, which can be a single stage mixersettler or other conventional type of extractor.
  • the raflinate is washed with a portion of the water phase from reflux decanter 29 and separated in raflinate extractor 8 into an aliphatic hydrocarbons phase (still called the rafl'inate) which is essentially free of solvent and water and contains about 97 percent to about 100 percent by weight aliphatics and about 0 percent to about 3 percent by weight aromatics, and a water phase as bottoms which contains about 75 percent to about 90 percent by weight water, about 10 percent to about 25 percent by weight solvent, and about 0.1 percent to about 1 percent by weight aliphatics.
  • an aliphatic hydrocarbons phase still called the rafl'inate
  • a water phase as bottoms which contains about 75 percent to about 90 percent by weight water, about 10 percent to about 25 percent by weight solvent, and about 0.1 percent to about 1 percent by weight aliphatics.
  • Part of this water phase can optionally be recirculated through extractor 8 via line 11, line 9 and line 5 as shown.
  • This recirculation is conventional with a mixersettler arrangement, but may not be advantageous with other types of extractors.
  • the water phase still contains, along with the water and solvent, a small amount of aliphatics. All or the balance of the water phase is, therefore, directed from line 11 along line 12 to extractor 13, which can again be a single-stage mixer-settler.
  • Feeding into line 12 via line 50 is an aromatics slipstream, which at its source (see line 14) is an essentially pure stream of aromatics, i.e., having a purity of a least percent by weight, or in other words, at least 95 percent by weight of the slipstream is aromatic hydrocarbons.
  • the purity of the slipstream is preferably about 98 percent and for optimum performance, i.e., to obtain the highest purity product, about 99 percent. It is called a slipstream or sidestream because the amount of aromatics fed into the water phase passing through line 12 is very small.
  • the amount of slipstream aromatic hydrocarbons used in the process is in the range of about 0.1 percent to about 5 percent by weight of the aromatic hydrocarbons in the feedstock and is preferably in the range of about 0.5 percent to about 2.0 percent by weight of such aromatic hydrocarbons.
  • the slipstream washes the water in extractor 13 to remove the small amount of aliphatics, which is so detrimental to the efficiency of the process.
  • This aromatics slipstream can be recycled along line 15 through extractor 13 to further wash the water phase where a mixer-settler extractor is used and it is then, preferably, sent along line 16 to line 1 where it is reintroduced into the feedstock and passes into the system once more.
  • the water which is essentially devoid of aliphatics, but contains solvent, then passes as bottoms from extractor 13 through line 17 and into water reservoir 51 via line 37.
  • the aqueous solvent percolates down the column carrying with it the aromatics.
  • the solvent solution of aromatics comes into countercurrent contact with a reflux liquid, which enters extractor 3 below the bottom tray along line 18.
  • the reflux percolates up the lower half of extractor 3 progressively dissolving in and purifying the solvent solution of aromatics.
  • the solution which is formed, i.e., the extract comprises about 5 percent to about 10 percent by weight feedstock aromatics, about 2 percent to about 5 percent by weight water, about 75 percent to about 85 percent by weight solvent, about 4 percent to about 8 percent by Weight reflux aromatics, and about 3 percent to about 6 percent by weight reflux aliphatics, all based on the total weight of the extract.
  • the extract leaves the bottom of extractor 3 through line 19 and passes through heat exchanger 22 where it is cooled to a temperature in the range of about 100 C. to about 125 C.
  • the extract proceeds along line 19 and enters stripper 23, the distillation zone, at upper flash chamber 24, which, as noted heretofore, is at a lower pressure than the extractor.
  • Part of the extract flashes on entering the flash chamber and is taken overhead through line 18 in vapor form.
  • Another part of the extract passes as a liquid into lower flash chamber 21, which is operated at an even lower pressure and further flashing occurs.
  • the balance of the extract (at least about 80 percent by weight) percolates down the column into the fractionation zone where it comes into countercurrent contact with the stripping vapors, i.e., steam, and more vapors are generated. A part of the vapor rises to the top of the column and mixes with the flashed vapors in flash chamber 21 as noted.
  • the overhead distillate comprises about 40 to about 75 percent by weight aromatics, about 20 to about 40 percent aliphatics, about 2 percent to about 10 percent by weight water, and about percent to about percent by weight solvent, all based on the total weight of the overhead distillate.
  • the side-stream distillate is comprised of about 65 to about 90 percent by weight aromatics, about to about 30 percent by weight water, and about 1 percent to about 10 percent by weight of solvent, based on the total weight of the side-stream distillate.
  • overhead distillate is a combination of flashed vapors and fractionated vapors having the aforementioned composition.
  • This overhead distillate is also known as a reflux distillate.
  • the vapor is first condensed and cooled to between about 38 C. and 94 C. in reflux condenser 25.
  • the condensate then passes into reflux decanter 29 where a reflux hydrocarbons phase is decanted from a water phase.
  • the reflux hydrocarbons phase comprises about 20 to 50 percent by weight aliphatics having from 5 to 7 carbon atoms, and about 50 to about 80 percent by weight aromatics and is recycled as reflux through line 18 to extractor 3 as previously described.
  • the water phase contains about 95 to about 99 percent by weight water, about 0 to about 5 percent by weight solvent, and about 0.1 to about 0.5 percent by weight aliphatics. It passes through line 31 and is split in two streams, lines 32 and 33, a raflinate wash stream and an aromatics Wash stream, respectively. These washes can take place as shown by splitting the stream or the entire stream can be used to Wash the raflinate first and then the aromatics providing that the water is treated with an aromatics slipstream before the aromatics Wash.
  • the side-stream distillate is withdrawn in vapor form from stripper 23 through line 26 and condensed in aromatics condenser 34 and further cooled to a temperature in the range of about 25 C. to about 50 C. in cooler 35, which can be a heat exchanger or other type of cooling device.
  • the condensate then passes into aromatics decanter 36 where an aromatic hydrocarbons phase containing about 99.8 to about 99.9 percent by weight aromatics, and about 0.1 to about 0.2 percent by Weight solvent and a Water phase containing about percent to about 98 percent by weight water, about 2 percent to about 10 percent by weight solvent, and about 0.1 percent to about 0.5 percent by Weight aromatics are formed.
  • the water phase passes through line 37 to Water reservoir 51.
  • all or part of the Water phase can be directed through valved line 38 to join line 32 for use as raflinate wash.
  • the aromatic hydrocarbons phase proceeds from decanter 36 through line 26 along which an aromatics slipstream is taken through line 14 to Wash water coming from reflux decanter 29 along line 33.
  • this slipstream can be in the range of about 0.10 percent to about 5.0 percent of the total aromatics in the feedstock and is preferably in the range of about 0.50 percent to about 2.0 percent of the total aromatics in the feedstock. These percentages are by weight.
  • the weight of the total aromatics is determined by analysis of a sample portion of the feedstock.
  • Aromatics added, e.g., as slipstream, during the process cycle are included in the determination.
  • the slipstream can, alternatively, be obtained from another source such as the overhead product of a benzene fractionating column, which is not shown in the drawing, or from a source completely removed from the system. As long as the slipstream has the previously noted high aromatics content, it will be satisfactory in this process.
  • Reflux water now essentially free of aliphatics, is withdrawn from wash extractor 39 and proceeds along line 43, which joins line 26, and passes into aromatics extractor 44, which can be a single stage mixer-settler or other type of extractor.
  • aromatics extractor 44 which can be a single stage mixer-settler or other type of extractor.
  • This reflux water along with water recycled from the settling zone in the case of a mixer-settler via line 45, which joins line 43, and process makeup water from line 46 (source not shown) contacts the aromatic product proceeding along line 26 into aromatics extractor 44 and recovers essentially all of the small amount of solvent remaining in the aromatics.
  • This water with solvent then proceeds along line 47 to join line 17, which joins line 37 and enters water reservoir 51.
  • High purity aromatic product is withdrawn from the process through line 26.
  • the total water in the system can be determined easily because the amount of water introduced can be controlled. Allowances must be made for water losses through leakage, entrainment and upsets, however.
  • Solvent can be recovered from this purge by directing the water through line 49 to join line 53 and enter solvent regenerator 52 where the solvent is separated from low boiling and high boiling impurities by steam distillation under vacuum. The solvent is recovered and recycled along line 54 to extractor 3 (connection not shown) and the Water and impurities discarded.
  • the slipstream taken through line 14 is first used to wash the water phase from reflux decanter 29 (i.e., one stream) and then the water phases from raflinate decanter 7 (optional) and raflinate extractor 8.
  • This procedure can be varied so that a different slipstream from a different source is used for each wash or, as previously mentioned, a single slipstream is used to wash one water phase where stream 31 is not split, but is first used to wash raflinate.
  • the slipstream picks up some aliphatics in extractor 39 before proceeding to extractor 13. It should be pointed out that the purity of this slipstream containing the small amount of aliphatics is only reduced by about one percent and that it still has a purity of at least about 95 percent by weight and preferably about 9 8 percent so that the definition of the slipstream with respect to purity is fulfilled.
  • a continuous solvent extraction-steam distillation process for the recovery of aromatic hydrocarbons having boiling points in the range of about 80 C. to about 175 C. from a feedstock containing aliphatic hydrocarbons and said aromatic hydrocarbons comprising the following steps:
  • step (g) contacting the water phase of step (d) with an aromatic hydrocarbons stream containing at least percent aromatic hydrocarbons, the amount of said stream being in the range of about 0.1 percent to about 5 percent by weight of the total aromatic hydrocarbons in the feedstock, to form an aromatic hydrocarbons phase and a water phase;
  • step (i) recycling the reflux hydrocarbons phase of the overhead distillate and the bottoms of step (b) to the extraction zone to provide reflux hydrocarbons and mixture of water and solvent, respectively, for step (a);
  • step (j) recovering the aromatic hydrocarbons phase of step (f) and the aliphatic hydrocarbons phase of step (d).
  • the ratio of solvent to feedstock in the extraction zone is in the range of about 3 to about 12 parts by weight of solvent to one part by weight of feedstock;
  • the amount of water in the extraction zone is about 1 percent to about 8 percent by weight based on the weight of the solvent in said zone;
  • the ratio of reflux to feedstock in the extraction zone is in the range of about 0.5 to about 1.5 parts by weight of reflux to one part by weight of feedstock;
  • the ratio of water to aromatic hydrocarbons in the distillation zone is in the range of about 0.1 to about 0.5 part by weight of water to one part by weight of aromatic hydrocarbons in said zone.
  • step (k) after step (a) and prior to step (d), separating the raflinate into an aliphatic hydrocarbons phase and a solvent phase;
  • step (k) recycling the solvent phase of step (k) to the extraction zone.
  • step (m) prior to step (k), removing water from the water phases of steps (f) and (g) in an amount in the range of about 0.25 percent to about 2.0 percent by weight of the total water used in the process.
  • a continuous solvent extraction-steam distillation process for the recovery of aromatic hydrocarbons having boiling points in the range of about 80 C. to about C. from a feedstock containing aliphatic hydrocarbons and said aromatic hydrocarbons comprising the following steps:
  • step (d) contacting the water phase of step (c) with an aromatic hydrocarbons stream containing at least 95 percent aromatic hydrocarbons, the amount of said stream being in the range of about 0.1 percent to about percent by weight of the total aromatic hydrocarbons in the feedstock, to form an aromatic hydrocarbons phase and a water phase;
  • step (f) recycling the water phase of step (e) to the distillation zone where said water phase is essentially converted to steam;
  • step (g) recycling the reflux hydrocarbons phase of the overhead distillate and the bottoms of step (b) to the extraction zone to provide reflux hydrocarbons and mixture of water and solvent, respectively, for step (a);
  • step (h) recovering the aromatic hydrocarbons phase of step (e) and the aliphatic hydrocarbons phase of step (c).
  • the temperature in the extraction zone is in the range of about 100 C. to about 200 C.
  • the pressure in the extraction zone is in the range of about 75 p.s.i.g. to about 200 p.s.i.g.
  • the temperature in the distillation zone is in the range of about 100 C. to about 200 C.
  • the pressure in the distillation zone is in the range of about 10 p.s.i.g. to about 35 p.s.1.g.
  • the ratio of solvent to feedstock in the extraction zone is in the range of of about 3 to about 12 parts by weight of solvent to one part by weight of feedstock;
  • the amount of water in the extraction zone is about 1 percent to about 8 percent by Weight based on the weight of the solvent in said zone;
  • the ratio of reflux to feedstock in the extraction 12 zone is in the range of about 0.5 to about 1.5 parts by weight of reflux to one part by weight of feedstock;
  • the ratio of water to aromatic hydrocarbons in the distillation zone is in the range of about 0.1 to about 0.5 part by weight of water to one part by weight of aromatic hydrocarbons in said zone.
  • step (i) after step (a) and prior to step (c), separating the raflinate into an aliphatic hydrocarbons phase and a solvent phase;
  • step (j) recycling the solvent phase of step (i) to the extraction zone.
  • step (k) prior to step (t), removing water from the water phase of step (d) in an amount in the range of about 0.25 percent to about 2.0 percent by weight of the total water used in the process.
  • step (d) recycling the aromatic hydrocarbons phase of step (d) to the extraction zone.

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US00180996A 1971-09-16 1971-09-16 Process for the separation of aromatic hydrocarbons from a mixed hydrocarbon feedstock Expired - Lifetime US3714033A (en)

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JP (1) JPS5320016B2 (xx)
AR (1) AR229226A1 (xx)
BE (1) BE788871A (xx)
BR (1) BR7206399D0 (xx)
CA (1) CA982156A (xx)
FR (1) FR2155945B1 (xx)
GB (1) GB1410773A (xx)
IT (1) IT967517B (xx)
NL (1) NL172337C (xx)

Cited By (29)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3779904A (en) * 1971-12-21 1973-12-18 Union Carbide Corp Process for the separation of aromatic hydrocarbons from a mixed hydrocarbon feedstock
US3864244A (en) * 1973-11-23 1975-02-04 Universal Oil Prod Co Solvent extraction with internal preparation of stripping steam
US3864245A (en) * 1973-11-23 1975-02-04 Universal Oil Prod Co Solvent extraction with increased polar hydrocarbon purity
US3944483A (en) * 1972-12-20 1976-03-16 Krupp-Koppers Gmbh Distillative recovery of aromatics with water addition in azeotropic proportions
US3966589A (en) * 1974-02-05 1976-06-29 Union Carbide Corporation Process for the separation of aromatic hydrocarbons from a mixed hydrocarbon feedstock
US4260476A (en) * 1980-01-31 1981-04-07 Union Carbide Corporation Separation of aromatic hydrocarbons from petroleum fractions
US4334983A (en) * 1980-06-30 1982-06-15 Exxon Research & Engineering Co. Stripping steam recycle for solvent recovery processes
US4342646A (en) * 1980-09-24 1982-08-03 Texaco Inc. Trace solvent recovery in selective solvent extraction
EP0098580A2 (en) * 1982-07-06 1984-01-18 Union Carbide Corporation Process for the separation of aromatic hydrocarbons from petroleum fractions with heat recovery
US4690733A (en) * 1985-03-20 1987-09-01 Union Carbide Corporation Process for the separation of hydrocarbons from a mixed feedstock
US4761222A (en) * 1985-12-20 1988-08-02 Phillips Petroleum Company Method for separating normally liquid organic compounds
US5022981A (en) * 1989-09-18 1991-06-11 Uop Aromatic extraction process using mixed polyalkylene glycol/glycol ether solvents
US5139651A (en) * 1989-09-18 1992-08-18 Uop Aromatic extraction process using mixed polyalkylene glycol/glycol ether solvents
US5191152A (en) * 1991-02-20 1993-03-02 Uop Process for the separation of aromatic hydrocarbons with energy redistribution
US5202520A (en) * 1989-03-09 1993-04-13 Uop Method for aromatic hydrocarbon recovery
US5225072A (en) * 1990-08-03 1993-07-06 Uop Processes for the separation of aromatic hydrocarbons from a hydrocarbon mixture
US5310480A (en) * 1991-10-31 1994-05-10 Uop Processes for the separation of aromatic hydrocarbons from a hydrocarbon mixture
US5336840A (en) * 1991-02-20 1994-08-09 Uop Process for the separation of aromatic hydrocarbons with energy redistribution
US5885422A (en) * 1997-02-26 1999-03-23 Stone & Webster Engineering Corporation Spent caustic (pre)treatment process
US20020158015A1 (en) * 1999-07-13 2002-10-31 Danisco A/S Process for separating essential oils from an essential oil-containing material
US6555726B1 (en) 1999-11-10 2003-04-29 Gaylord Chemical Corporation Methods for enhanced extractive distillation employing extractive distillation compositions comprising sulfolane and compatibility agent
US6617483B1 (en) 2000-05-03 2003-09-09 Gaylord Chemical Corporation Polyalkylene glycol compositions for enhanced aromatic extraction
US6660899B2 (en) 2001-02-14 2003-12-09 Gaylord Chemical Corporation Methods for enhanced aromatic extraction employing sulfone-sulfoxide compositions
US20130146508A1 (en) * 2011-12-07 2013-06-13 IFP Energies Nouvelles Process for coal conversion comprising at least one step of liquefaction for the manufacture of aromatics
WO2014127487A1 (en) 2013-02-25 2014-08-28 Meg Energy Corp. Improved separation of solid asphaltenes from heavy liquid hydrocarbons using novel apparatus and process ("ias")
US9115315B2 (en) 2006-04-26 2015-08-25 Fina Technology, Inc. Petrochemical processes
US9200211B2 (en) 2012-01-17 2015-12-01 Meg Energy Corp. Low complexity, high yield conversion of heavy hydrocarbons
US9481835B2 (en) 2010-03-02 2016-11-01 Meg Energy Corp. Optimal asphaltene conversion and removal for heavy hydrocarbons
US11028329B1 (en) 2020-04-10 2021-06-08 Saudi Arabian Oil Company Producing C6-C8 aromatics from FCC heavy naphtha

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
BR7402696A (pt) * 1974-02-05 1975-12-09 Union Carbide Corp Processo de extracao por solvente de destilacao a vapor para recuperacao de hidrocarbonetos aromaticos
US4604683A (en) * 1984-12-10 1986-08-05 Advanced Computer Communications Communication controller using multiported random access memory

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Publication number Priority date Publication date Assignee Title
US3179708A (en) * 1961-09-18 1965-04-20 Universal Oil Prod Co Solvent extraction of aromatics from hydrocarbon mixtures
NL283421A (xx) * 1961-09-21

Cited By (38)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3779904A (en) * 1971-12-21 1973-12-18 Union Carbide Corp Process for the separation of aromatic hydrocarbons from a mixed hydrocarbon feedstock
US3944483A (en) * 1972-12-20 1976-03-16 Krupp-Koppers Gmbh Distillative recovery of aromatics with water addition in azeotropic proportions
US3864244A (en) * 1973-11-23 1975-02-04 Universal Oil Prod Co Solvent extraction with internal preparation of stripping steam
US3864245A (en) * 1973-11-23 1975-02-04 Universal Oil Prod Co Solvent extraction with increased polar hydrocarbon purity
US3966589A (en) * 1974-02-05 1976-06-29 Union Carbide Corporation Process for the separation of aromatic hydrocarbons from a mixed hydrocarbon feedstock
US4260476A (en) * 1980-01-31 1981-04-07 Union Carbide Corporation Separation of aromatic hydrocarbons from petroleum fractions
US4334983A (en) * 1980-06-30 1982-06-15 Exxon Research & Engineering Co. Stripping steam recycle for solvent recovery processes
US4342646A (en) * 1980-09-24 1982-08-03 Texaco Inc. Trace solvent recovery in selective solvent extraction
EP0098580A2 (en) * 1982-07-06 1984-01-18 Union Carbide Corporation Process for the separation of aromatic hydrocarbons from petroleum fractions with heat recovery
EP0098580A3 (en) * 1982-07-06 1986-04-16 Union Carbide Corporation Process for the separation of aromatic hydrocarbons from petroleum fractions with heat recovery
US4690733A (en) * 1985-03-20 1987-09-01 Union Carbide Corporation Process for the separation of hydrocarbons from a mixed feedstock
EP0290656A1 (en) * 1985-03-20 1988-11-17 Uop Process for the separation of hydrocarbons from a mixed feedstock
AU601419B2 (en) * 1985-03-20 1990-09-13 Union Carbide Corporation Process for the separation of hydrocarbons from a mixed feedstock
US4761222A (en) * 1985-12-20 1988-08-02 Phillips Petroleum Company Method for separating normally liquid organic compounds
US5202520A (en) * 1989-03-09 1993-04-13 Uop Method for aromatic hydrocarbon recovery
US5022981A (en) * 1989-09-18 1991-06-11 Uop Aromatic extraction process using mixed polyalkylene glycol/glycol ether solvents
US5139651A (en) * 1989-09-18 1992-08-18 Uop Aromatic extraction process using mixed polyalkylene glycol/glycol ether solvents
US5225072A (en) * 1990-08-03 1993-07-06 Uop Processes for the separation of aromatic hydrocarbons from a hydrocarbon mixture
US5336840A (en) * 1991-02-20 1994-08-09 Uop Process for the separation of aromatic hydrocarbons with energy redistribution
US5191152A (en) * 1991-02-20 1993-03-02 Uop Process for the separation of aromatic hydrocarbons with energy redistribution
US5310480A (en) * 1991-10-31 1994-05-10 Uop Processes for the separation of aromatic hydrocarbons from a hydrocarbon mixture
US5885422A (en) * 1997-02-26 1999-03-23 Stone & Webster Engineering Corporation Spent caustic (pre)treatment process
US20020158015A1 (en) * 1999-07-13 2002-10-31 Danisco A/S Process for separating essential oils from an essential oil-containing material
US6555726B1 (en) 1999-11-10 2003-04-29 Gaylord Chemical Corporation Methods for enhanced extractive distillation employing extractive distillation compositions comprising sulfolane and compatibility agent
US6617483B1 (en) 2000-05-03 2003-09-09 Gaylord Chemical Corporation Polyalkylene glycol compositions for enhanced aromatic extraction
US6660899B2 (en) 2001-02-14 2003-12-09 Gaylord Chemical Corporation Methods for enhanced aromatic extraction employing sulfone-sulfoxide compositions
US9115315B2 (en) 2006-04-26 2015-08-25 Fina Technology, Inc. Petrochemical processes
US9890337B2 (en) 2010-03-02 2018-02-13 Meg Energy Corp. Optimal asphaltene conversion and removal for heavy hydrocarbons
US9481835B2 (en) 2010-03-02 2016-11-01 Meg Energy Corp. Optimal asphaltene conversion and removal for heavy hydrocarbons
US9074139B2 (en) * 2011-12-07 2015-07-07 IFP Energies Nouvelles Process for coal conversion comprising at least one step of liquefaction for the manufacture of aromatics
US20130146508A1 (en) * 2011-12-07 2013-06-13 IFP Energies Nouvelles Process for coal conversion comprising at least one step of liquefaction for the manufacture of aromatics
US9200211B2 (en) 2012-01-17 2015-12-01 Meg Energy Corp. Low complexity, high yield conversion of heavy hydrocarbons
US9944864B2 (en) 2012-01-17 2018-04-17 Meg Energy Corp. Low complexity, high yield conversion of heavy hydrocarbons
WO2014127487A1 (en) 2013-02-25 2014-08-28 Meg Energy Corp. Improved separation of solid asphaltenes from heavy liquid hydrocarbons using novel apparatus and process ("ias")
US9976093B2 (en) 2013-02-25 2018-05-22 Meg Energy Corp. Separation of solid asphaltenes from heavy liquid hydrocarbons using novel apparatus and process (“IAS”)
US10280373B2 (en) 2013-02-25 2019-05-07 Meg Energy Corp. Separation of solid asphaltenes from heavy liquid hydrocarbons using novel apparatus and process (“IAS”)
US11028329B1 (en) 2020-04-10 2021-06-08 Saudi Arabian Oil Company Producing C6-C8 aromatics from FCC heavy naphtha
WO2021206739A1 (en) 2020-04-10 2021-10-14 Saudi Arabian Oil Company Process and apparatus for producing c6-c8 aromatics from fcc heavy naphtha

Also Published As

Publication number Publication date
AR229226A1 (es) 1983-07-15
BR7206399D0 (pt) 1973-08-23
NL172337C (nl) 1983-08-16
NL172337B (nl) 1983-03-16
GB1410773A (en) 1975-10-22
DE2245502B2 (de) 1977-04-07
DE2245502A1 (de) 1973-03-22
IT967517B (it) 1974-03-11
CA982156A (en) 1976-01-20
JPS4836124A (xx) 1973-05-28
FR2155945B1 (xx) 1975-09-12
NL7212549A (xx) 1973-03-20
JPS5320016B2 (xx) 1978-06-24
FR2155945A1 (xx) 1973-05-25
BE788871A (fr) 1973-03-15

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