Abstract: A membrane process for the removal of sulfur species from a naphtha feed, in particular, a FCC light cat naphtha, without a substantial loss of olefin yield is disclosed. The process involves contacting a naphtha feed stream with a membrane having sufficient flux and selectivity to separate a sulfur deficient retentate fraction from a sulfur enriched permeate fraction, preferably, under pervaporation conditions. Sulfur deficient retentate fractions are useful directly into the gasoline pool. Sulfur-enriched permeate fractions are rich in sulfur containing aromatic and nonaromatic hydrocarbons and are further treated with conventional sulfur removal technologies, e.g. hydrotreating, to reduce sulfur content. The process of the invention provides high quality naphtha products having a reduced sulfur content and a high content of olefin compounds.

Abstract: The levels of iron sulfide present in a conduit, such as a pipeline, are reduced by contacting the conduit, on an inner surface, with a composition obtained from an aqueous solution containing at least one compound of Formula (I) and at least one amine or corresponding ammonium derivative in the presence of a solvent, wherein X is an anion of valency n. Preferably, the pH of the solution is about 8. Alternatively, the method employs a composition comprising tris(hydroxymethyl)phosphine (TRIS) and at least one amine or corresponding ammonium derivative. The amine preferably is ammonia or a primary alkylamine. The compositions readily complex and thereby dissolve deposits of iron(II) sulfide, removing them from the conduit.

Abstract: Apparatus and processes are disclosed for economical separation of fluid mixtures utilizing perm-selective membranes. Broadly, apparatus of the invention comprises a plurality of membrane modules comprising a solid perm-selective membrane and equipment for controlling enthalpy of selected fluids within the apparatus. Advantageously, the membrane modules are disposed in a first product group, a second product group, and at least one intermediate group. Apparatus of the invention is particularly useful for simultaneous recovery of a very pure permeate product, and/or a desired non-permeate stream, from fluid mixtures of two or more compounds which when subjected to appropriately altered conditions of temperature and/or pressure exhibit a bubble point.

Abstract: An onboard fuel separation apparatus separates a material fuel (gasoline) into a high-octane fuel having a higher octane value than the material fuel and a low-octane fuel having a lower octane value than the material fuel using a separation membrane which selectively allows high-octane value components (such as aromatic components) permeate through the membrane. The apparatus increases the ratio of the amount of the high-octane value components permeating through the membrane to the amount of the high-octane value components contained in the material fuel by, (A) Controlling the temperature of the material fuel supplied to the membrane (B) Increasing partial pressure of the low-octane value components on the high-octane fuel side of the membrane and removing volatiles from the permeate, and (C) Bypassing volatiles in the material feed around the membrane.

Abstract: A process for treating mixtures of organic components, including azeotropic mixtures. The process includes a gas- or liquid-phase membrane separation step in conjunction with a dephlegmation step to treat at least a portion of the permeate vapor from the pervaporation step. The process yields a membrane residue stream, a stream enriched in the more volatile component as the overhead stream from the dephlegmator and a condensate stream enriched in the less volatile component as a bottoms stream from the dephlegmator. Any of these may be the principal product of the process.

Abstract: A membrane process for the removal of sulfur species from a naphtha feed, in particular, a FCC light cat naphtha, without a substantial loss of olefin yield is disclosed. The process involves contacting a naphtha feed stream with a membrane having sufficient flux and selectivity to separate a sulfur deficient retentate fraction from a sulfur enriched permeate fraction, preferably, under pervaporation conditions. Sulfur deficient retentate fractions are useful directly into the gasoline pool. Sulfur-enriched permeate fractions are rich in sulfur containing aromatic and nonaromatic hydrocarbons and are further treated with conventional sulfur removal technologies, e.g. hydrotreating, to reduce sulfur content. The process of the invention provides high quality naphtha products having a reduced sulfur content and a high content of olefin compounds.

Abstract: An improvement in the alkylation of olefins with isoalkanes in the presence of sulfuric acid wherein the sulfuric acid is removed from the product by a mechanical coalescer means prior to fractionation. No water wash or caustic treatment is required. Any sulfonates or sulfonic esters are removed by hydrodesulfurization or decomposition catalyst in a separate reactor or in either the deisobutanizer (DIB) or debutanizer (DB) column.

Abstract: A continuous process to separate colour bodies and/or asphalthenic contaminants from a hydrocarbon mixture by passing part of the hydrocarbon mixture through a membrane over which membrane a pressure difference is maintained thereby obtaining a hydrocarbon permeate having a reduced content of colour bodies and/or contaminants, wherein at regular time intervals the pressure difference over the membrane is substantially lowered.

Abstract: Chitosan membranes chelated with silver or cuprous material may be used to separate olefins from a mixture of olefins and paraffins. The feed stream is humidified, demisted, treated to remove sulfur compounds and passed to a cell having a chitosan membrane containing chelated silver or cuprous compounds. The process has a reasonable flux rate and is operable at reasonable temperatures and pressures. The process could be used in an olefin separation train.

Abstract: A membrane process for the removal of sulfur species from a naphtha feed, in particular, a FCC light cat naphtha, without a substantial loss of olefin yield is disclosed. The process involves contacting a naphtha feed stream with a membrane having sufficient flux and selectivity to separate a sulfur deficient retentate fraction from a sulfur enriched permeate fraction, preferably, under pervaporation conditions. Sulfur deficient retentate fractions are useful directly into the gasoline pool. Sulfur-enriched permeate fractions are rich in sulfur containing aromatic and nonaromatic hydrocarbons and are further treated with conventional sulfur removal technologies, e.g. hydrotreating, to reduce sulfur content. The process of the invention provides high quality naphtha products having a reduced sulfur content and a high content of olefin compounds.

Abstract: A membrane process for the removal of sulfur species from a naphtha feed, in particular, a FCC light cat naphtha, without a substantial loss of olefin yield is disclosed. The process involves contacting a naphtha feed stream with a membrane having sufficient flux and selectivity to separate a sulfur deficient retentate fraction from a sulfur enriched permeate fraction, preferably, under pervaporation conditions. Sulfur deficient retentate fractions are useful directly into the gasoline pool. Sulfur-enriched permeate fractions are rich in sulfur containing aromatic and nonaromatic hydrocarbons and are further treated with conventional sulfur removal technologies, e.g. hydrotreating, to reduce sulfur content. The process of the invention provides high quality naphtha products having a reduced sulfur content and a high content of olefin compounds.

Abstract: Gas-impermeable membranes containing a molten salt electrolyte in an electron-conducting matrix provide for mixed ion and electron conduction across the membrane. The membranes mediate transport of a selected ion for gas separation and or catalytic reactions at the membrane surface. The membranes are useful in catalytic membrane reactors, particularly for gas separation and full or partial oxidation reactions. The membranes are of particular interest for mediation of oxide ions, such as carbonate, for carbon dioxide separation or for partial oxidation reactions. Catalytic membrane reactors can incorporate catalyst layers on the membrane surfaces and or three-dimension catalysts, e.g., packed-bed catalysts, in the oxidation zone or the reduction zone of the reactor. The invention also relates to methods of gas separation and method for generating products employing the membranes and catalytic membrane reactors of this invention.

Abstract: A method of separating or concentrating hydrocarbon-containing gas mixtures such as hydrogen from hydrocarbons, carbon dioxide from hydrocarbons, nitrogen from hydrocarbons, and hydrocarbons from one another using a selectively permeable membrane. The method is well suited to separate hydrocarbon-containing mixtures such as those generated by petroleum refining industries, petrochemical industries, natural gas processing, and the like. The membranes exhibit extremely good resistance to plasticization by hydrocarbon components in the gas mixture under practical industrial process conditions.

Abstract: A process for removing sulfur from a hydrocarbon employs a solid membrane. A feed stream is provided containing a feed liquid hydrocarbon and a feed sulfur species and a sweep stream is provided containing a sweep liquid hydrocarbon. A relatively large quantity of the feed stream is conveyed past one side of the solid membrane, while a relatively small quantity of the sweep stream is conveyed past the opposite side of the solid membrane. The feed sulfur species is transported in a permeate from the feed stream through the solid membrane to the sweep stream. As a result, the feed stream is converted to a relatively large quantity of a substantially sulfur-free reject stream containing a primary hydrocarbon product, while the sweep stream combines with the permeate to produce a relatively small quantity of a sulfur-enriched stream, which is amenable to further processing.

Abstract: Methods for the separation of sulfur compounds from a hydrocarbon mixture using an ionic membrane are provided. Preferred ionic membranes are Nafion®-type (polymers of perfluorosulfonic acid) membranes and derivatives thereof. Preferred applications include the removal of sulfur contaminants from light cracked naphthas.

Abstract: A process for the separation of sulfur compounds from a hydrocarbon mixture using a membrane is provided. Preferred hydrocarbon mixtures are oil refining fractions such as light cracked naphtha. Membranes are composed of either ionic or non-ionic materials and preferentially permeate sulfur compounds over other hydrocarbons. A single or multi-stage membrane system separates the hydrocarbon mixture into a sulfur-rich fraction and a sulfur-lean fraction. The sulfur-lean fraction may be used in fuel mixtures and the sulfur-rich fraction may be further treated for sulfur reduction.

Abstract: A process for the separation of mixture components uses a supercritical fluid that is fresh to at least one side of a nonporous membrane after which the fluid is either recycled to the opposite side of the membrane or removed from the separation process. Fluids and membranes, including modified membranes, are provided to facilitate passage of one or more components of a mixture through the membrane while retarding passage of other components of the mixture. The process is useful for the separation of mixtures with similar components including axeotropic mixtures and pharmaceutical and biological products.

Abstract: A process for the separation of sulfur compounds from a hydrocarbon mixture using a membrane is provided. Preferred hydrocarbon mixtures are oil refining fractions such as light cracked naphtha. Membranes are composed of either ionic or non-ionic materials and preferentially permeate sulfur compounds over other hydrocarbons. A single or multi-stage membrane system separates the hydrocarbon mixture into a sulfur-rich fraction and a sulfur-lean fraction. The sulfur-lean fraction may be used in fuel mixtures and the sulfur-rich fraction may be further treated for sulfur reduction.

Abstract: A method for separating p-xylene by separating and recovering only p-xylene from a p-xylene-containing raw material mixture under high-temperature and high-pressure conditions using a zeolite membrane as a separating membrane is provided. The p-xylene partial pressure at the raw material side of the separating membrane is kept at a sufficiently high pressure and the p-xylene partial pressure at the recovery side of the separating membrane is controlled at a pressure which is not higher than the inflection point of p-xylene adsorption curve. This method for separating p-xylene using a zeolite membrane as a separating membrane can secure a sufficient p-xylene permeation amount and has industrial applicability.

Abstract: An improved process for separating hydrogen from hydrocarbons. The process includes a pressure swing adsorption step, a compression/cooling step and a membrane separation step. The membrane step uses a rubbery polymeric membrane selective for all C1-C6 hydrocarbons over hydrogen. The process can produce three products: a high-purity hydrogen stream, an LPG stream and a light hydrocarbon fuel gas stream.

Abstract: A process for the production of naphtha streams from cracked naphthas having sulfur levels which help meet future EPA gasoline sulfur standards (30 ppm range and below).

Abstract: The invention relates to a process for the treatment of a gas stream obtained from the production of polyolefins and containing unreacted compounds. According to the process, uncondensed compounds are removed from the gas stream and, when so desired, these compounds are directed to further treatment. According to the invention, the uncondensed compounds are separated from the gas stream by membrane separation. Thus the separation of gases is facilitated, since by coupling the membrane system in conjunction with distillation columns the distillation can be carried out at a substantially higher top temperature. By using the membrane system it is possible effectively to remove the lightest gases, which would otherwise accumulate in the process.

Abstract: In order to recover hydrogen from a hydrogen-rich gaseous effluent, a procedure is used that comprises:

Abstract: A membrane process for the removal of sulfur species from a naphtha feed, in particular, a FCC light cat naphtha, without a substantial loss of olefin yield is disclosed. The process involves contacting a naphtha feed stream with a membrane having sufficient flux and selectivity to separate a sulfur deficient retentate fraction from a sulfur enriched permeate fraction, preferably, under pervaporation conditions. Sulfur deficient retentate fractions are useful directly into the gasoline pool. Sulfur-enriched permeate fractions are rich in sulfur containing aromatic and nonaromatic hydrocarbons and are further treated with conventional sulfur removal technologies, e.g. hydrotreating, to reduce sulfur content. The process of the invention provides high quality naphtha products having a reduced sulfur content and a high content of olefin compounds.

Abstract: A process for manufacturing cumene by reacting propylene with benzene, including treating a vent stream from the reaction zone, to recover propylene for return to the reactor. The process involves using a gas separation membrane to separate propylene from propane in the reactor vent stream. The membrane separation step results in a residue stream typically containing as much as 30%, 40% or more propane, which is vented from the process, and a permeate stream containing 95% or less propylene, which is recirculated to the reactor.

Abstract: Separation of ethylene from ethane is achieved by feeding a mixture of the C2 hydrocarbons in contact with a CTS-1 crystalline titanium silicate molecular sieve which has a controlled pore size to selectively adsorb ethylene and size exclude ethane. The feed stream can also contain acetylene which can be selectively adsorbed from both ethane and ethylene by further controlling the pore size of the CTS-1 molecular sieve. Propane/propylene separation is also disclosed.

Abstract: A membrane process for the removal of sulfur species from a naphtha feed, in particular, a FCC light cat naphtha, without a substantial loss of olefin yield is disclosed. The process involves contacting a naphtha feed stream with a membrane having sufficient flux and selectivity to separate a sulfur deficient retentate fraction from a sulfur enriched permeate fraction, preferably, under pervaporation conditions. Sulfur deficient retentate fractions are useful directly into the gasoline pool. Sulfur-enriched permeate fractions are rich in sulfur containing aromatic and nonaromatic hydrocarbons and are further treated with conventional sulfur removal technologies, e.g. hydrotreating, to reduce sulfur content. The process of the invention provides high quality naphtha products having a reduced sulfur content and a high content of olefin compounds.

Abstract: A process for removing sulfur from a hydrocarbon employs a solid membrane. A feed stream is provided containing a feed liquid hydrocarbon and a feed sulfur species and a sweep stream is provided containing a sweep liquid hydrocarbon. A relatively large quantity of the feed stream is conveyed past one side of the solid membrane, while a relatively small quantity of the sweep stream is conveyed past the opposite side of the solid membrane. The feed sulfur species is transported in a permeate from the feed stream through the solid membrane to the sweep stream. As a result, the feed stream is converted to a relatively large quantity of a substantially sulfur-free reject stream containing a primary hydrocarbon product, while the sweep stream combines with the permeate to produce a relatively small quantity of a sulfur-enriched stream, which is amenable to further processing.

Abstract: A process for the separation of sulfur compounds from a hydrocarbon mixture using a membrane is provided. Preferred hydrocarbon mixtures are oil refining fractions such as light cracked naphtha. Membranes are composed of either ionic or non-ionic materials and preferentially permeate sulfur compounds over other hydrocarbons. A single or multi-stage membrane system separates the hydrocarbon mixture into a sulfur-rich fraction and a sulfur-lean fraction. The sulfur-lean fraction may be used in fuel mixtures and the sulfur-rich fraction may be further treated for sulfur reduction.

Abstract: This invention relates to a process and a chemical plant for the production primarily of paraxylene. In particular the process and chemical plant utilize zeolite membranes for enhanced paraxylene production.

Abstract: The process of the invention is a process for selective hydrogenation of a hydrocarbon feed containing hydrogen and C2+ hydrocarbons, characterized in that it comprises at least one step for separating a fraction of the hydrogen contained in the feed by means of a membrane (step a)) and a step for selective hydrogenation of the effluent from step a) in a reactive column (step b)).

Abstract: A process for recovering halides from hydrocarbon containing streams is disclosed using a sulfonated hexafluro bis-A-polysulfone membrane of polymers and copolymers having the polymer repeat unit of the formula: in the polymer or copolymer. This process is applicable to recovering and recycling hydrogen chloride, which is used as a catalytic promoter, in hydrocarbon conversion processes such as isomerization and alkylation.

Abstract: A method for separation of p-xylene by separating and recovering only p-xylene from a p-xylene-containing raw material mixture under high-temperature and high-pressure conditions using a zeolite membrane as a separating membrane, in which method the p-xylene partial pressure at the raw material side of the separating membrane is kept at a sufficiently high pressure and the p-xylene partial pressure at the recovery side of the separating membrane is controlled at a pressure which is not higher than the inflexion point of p-xylene adsorption curve. This method for separation of p-xylene using a zeolite membrane as a separating membrane can secure a sufficient p-xylene permeation amount and has industrial applicability.

Abstract: A membrane and membrane separation process useful in gas, vapor and liquid separations. The membrane comprises a separating layer of a polymer that is characterized by a high glass transition temperature, Tg, such as at least about 100° C., and a high free volume within the polymer material itself, such as a fractional free volume of at least about 0.20. Within the polymer material are dispersed fine non-porous particles, such as silica or carbon black particles, having an average diameter no greater than about 1,000 Å. The membrane is particularly useful for separating C3+ hydrocarbons from other gases.

Abstract: A process for recovering halides from hydrocarbon containing streams is disclosed using a sulfonated hexafluro bis-A-polysulfone membrane of polymers and copolymers having the polymer repeat unit of the formula: in the polymer or copolymer. This process is applicable to recovering and recycling hydrogen chloride, which is used as a catalytic promoter, in hydrocarbon conversion processes such as isomerization and alkylation.

Abstract: A process for recovering halides from hydrocarbon containing streams is disclosed using a sulfonated hexafluro bis-A-polysulfone membrane of polymers and copolymers having the polymer repeat unit of the formula: in the polymer or copolymer. This process is applicable to recovering and recycling hydrogen chloride, which is used as a catalytic promoter, in hydrocarbon conversion processes such as isomerization and alkylation.

Abstract: Processes and apparatus for providing improved catalytic cracking, specifically improved recovery of olefins, LPG or hydrogen from catalytic crackers. The improvement is achieved by passing part of the wet gas stream across membranes selective in favor of light hydrocarbons over hydrogen.

Abstract: A process for hydroprocessing a fluid stream containing at least hydrogen and hydrocarbons. The process uses a hydrocarbon-selective membrane to reduce the concentration of hydrocarbons and contaminants in the hydrogen stream recycled to the hydroprocessing reactor. The membrane can operate in the presence of hydrogen sulfide. The process also provides the opportunity for increased NGL recovery from the hydrocarbon-enriched membrane permeate stream.

Abstract: Permselective separation of aromatic hydrocarbons from non-aromatic hydrocarbons in a feed stream is accomplished using improved asymmetric membranes. The preferred membranes are fashioned from a polyimide and conditioned with a lubricating oil. Feed streams containing a mixture of aromatic and non-aromatic hydrocarbons are contacted with the dense active layer side of the polyimide membrane under a pressure and temperature sufficient to selectively permeate the desired aromatic hydrocarbon.

Abstract: Processes and apparatus for providing improved contaminant removal and hydrogen recovery in hydrogenation reactors, particularly in refineries and petrochemical plants. The improved contaminant removal is achieved by selective purging, by passing gases in the hydrogenation reactor recycle loop or purge stream across membranes selective in favor of the contaminant over hydrogen.

Abstract: Processes and apparatus for providing improved contaminant removal and hydrogen reuse in reactors, particularly in refineries and petrochemical plants. The improved contaminant removal is achieved by selective purging, by passing gases in the reactor recycle loop across membranes selective in favor of the contaminant over hydrogen.

Abstract: Processes and apparatus for providing improved catalytic reforming, specifically improved recovery of reformate and hydrogen from catalytic reformers. The improvement is achieved by passing portions of the reactor effluent or streams derived from the reactor effluent across membranes selective in favor of light hydrocarbons over hydrogen.

Abstract: For producing three effluents which are respectively rich in straight chain paraffins, in mono-branched paraffins, and in di-branched and tri-branched paraffins possibly with naphthenic and/or aromatic compounds, from C5-C8 cuts or intermediate cuts (C5-C7, C6-C8, C7-C8, C6-C7, C7 or C8), comprising paraffic and possibly naphthenic, aromatic and olefinic hydrocarbons, the separation process of the invention uses at least two separation units operating either by adsorption or by permeation. It is of particular application when coupled with a hydro-isomerization process, which selectively recycles straight chain and mono-branched paraffins, necessary with paraffins containing more than 7 carbon atoms.

Abstract: The aqueous wash stream of an electrolytic precipitation system treating natural gas liquid (NGL) is maintained at a pH sufficiently basic to decrease the solubility of iron sulfide in the aqueous wash stream.

Abstract: Producing light olefins from a contaminated liquid hydrocarbon feed by means of thermal cracking of, which process comprises the steps of supplying the feed (6) to the inlet (7) of a membrane unit (1) provided with a polysiloxane membrane (10), and removing from the permeate side (9) a permeate (14) and from the retentate side (8) a retentate (12); supplying the permeate (14) to the inlet of a cracking furnace (2), allowing the permeate to crack in the coils (15, 16) of the cracking furnace (2) in the presence of steam (17) at elevated temperature and removing from the cracking furnace (2) a cracked stream (19) which is enriched in light olefins; quenching (22, 24) the cracked stream; supplying the cooled cracked stream to a fractionation column (3); supplying the retentate (12) to the fractionation column (3); and removing from the fractionation column (3); a gaseous stream (30), a side stream of fuel oil components (45) and a bottom stream (50).

Abstract: A process for treating gas streams containing hydrogen and hydrocarbons. The process includes a membrane conditioning step to remove C.sub.5 -C.sub.8 hydrocarbons, followed by a selective adsorption or membrane separation step to separate hydrogen from methane. The membrane conditioning step uses a membrane selective for C.sub.5 -C.sub.8 hydrocarbons over hydrogen.

Abstract: Compositions useful in separating molecules or catalytic conversions comprise a substrate, a zeolite or zeolite-like layer, a selectivity enhancing coating in contact with the zeolite layer and optionally a permeable intermediate layer in contact with the substrate the zeolite layer being in contact either with the substrate or the optional intermediate layer.

Abstract: A method of distilling a crude oil and a contaminated liquid stream in an atmospheric distillation column (2) comprising the steps of (a) heating (13, 15) the crude oil at atmospheric pressure and introducing the heated crude oil into the inlet section (10) of the column (2); (b) removing from bottom a residue (19), removing from the top an overhead (20) and removing from the rectification section (7) at least one side stream (26, 28); (c) cooling (13) one of the side streams (28) and introducing the cooled side stream (29) into the rectification section (7) and partly condensing (21) the overhead (20) and introducing the condensed fraction (24) into the upper end of the distillation column (2); (d) supplying the contaminated liquid stream (40) to a membrane unit (3) provided with a suitable membrane (33), and removing a permeate (37) and a retentate (36); and (e) introducing the permeate (37) into the rectification section (7) and adding the retentate (36) to the crude oil (11) upstream of the furnace (1).

Abstract: In a process for separating linear from branched hydrocarbons, the feed is brought in contact with a carbon membrane with critical size from 0.39 to 0.55 nm. The isomer with the larger size remains on the feed side. A membrane can be produced by activating a membrane by reacting it with oxygen and then with hydrogen.

Abstract: To reduce the benzene content of a hydrocarbon mixture that contains benzene and other hydrocarbons, the mixture is fed to a distillation column so as to separate an overhead distillate, a bottom residue, and a sidestream having a benzene content richer than in the distillate and in the residue; the resultant sidestream is sent to at least one permeation zone to permeate the benzene selectively and retain a retentate having a reduced content of benzene; and at least part of the retentate is recycled to at least one level in the distillation column, preferably two levels, one at above and one below the feedpoint to the column. The permeate benzene stream is optionally subjected to extractive distillation in order to increase the purity of the resultant benzene.