Abstract: Processes and compositions for scavenging hydrogen sulfide from hydrocarbon streams are disclosed that reduce, if not substantially eliminate, the formation of crystalline or amorphous solids even under cold conditions. The compositions used in the processes comprise a hexahydrotriazine component and an amphiphilic component that form a hydrophobic micelle when the hexahydrotriazine component becomes spent.

Abstract: A process for the separation of the aromatic compounds benzene, toluene and xylene from an aromatics-containing reformate gasoline and pyrolysis gasoline or a coke-oven light oil or an aromatics-containing refinery stream, in which the aromatics are separated by an extractive distillation uses a novel solvent combination made up of the compounds n,n?-diformyl piperazine or 2,2-bis-(cyanoethyl)ether in a combination with n-formyl morpholine as a second solvent for extractive distillation so that the solvent combination obtained shows a higher selectivity with regard to the aromatics to be extracted so that a lower solvent load is required. The aromatics-containing feed mixture is first submitted to a pre-distillation so that the obtained fraction has a narrow boiling point range. This fraction is then submitted to an extractive distillation in a first column, in which an aromatics-lean head product of predominantly paraffinic hydrocarbons is obtained as well as an aromatics-enriched bottom product.

Abstract: A method for suppressing isomerization of an olefin metathesis product produced in a metathesis reaction includes adding an isomerization suppression agent that includes nitric acid to a mixture that includes the olefin metathesis product and residual metathesis catalyst from the metathesis reaction under conditions that are sufficient to passivate at least a portion of the residual metathesis catalyst. Methods of refining a natural oil are described.

Abstract: A method for suppressing isomerization of an olefin metathesis product produced in a metathesis reaction includes adding an isomerization suppression agent to a mixture that includes the olefin metathesis product and residual metathesis catalyst from the metathesis reaction under conditions that are sufficient to passivate at least a portion of the residual metathesis catalyst. The isomerization suppression agent is phosphorous acid, a phosphorous acid ester, phosphinic acid, a phosphinic acid ester or combinations thereof. Methods of refining natural oils are described.

Abstract: Processes for obtaining aromatic hydrocarbons from a hydrocarbon mixture comprising aromatic and nonaromatic hydrocarbons and high boilers comprising: (A) providing a hydrocarbon mixture a1 and an extractive solvent a2, (B) extractively distilling the mixture a1 with the extractive solvent to obtain a mixture b1 of extractive solvent, the aromatic hydrocarbons, and high boilers, (C) distilling the mixture b1 to one or more fractions c1 comprising aromatic hydrocarbons and the extractive solvent c2 comprising high boilers, (D) removing a substream d1 from the extractive solvent c2, (E) extracting the substream d1 of the extractive solvent with water to obtain an aqueous extract phase e1 essentially free of high boilers and an organic phase e2 comprising the high boilers, (F) distilling the aqueous extract phase e1 and recovering the extractive solvent a2. Step (E) is preceded by a distillation in which a fraction of very high-boiling hydrocarbons is removed from substream d1.

Abstract: This invention relates to a process for removing metals, particularly mercury, from hydrocarbon streams by use of an ionic liquid, where in the metal-containing hydrocarbon stream is contacted with an ionic liquid to produce a product hydrocarbon stream having reduced mercury content.

Abstract: An industrially advantageous method for producing a high purity terminal olefin is disclosed, comprising the steps of (a) contacting a mixture comprising a terminal olefin represented by formula (1): and one or more corresponding internal olefins as impurities, with a brominating agent in the presence of water or an alcohol, to convert the internal olefin(s) to compound(s) having a higher boiling point than the terminal olefin; and (b) purifying the terminal olefin by distillation from the reaction mixture.

Abstract: Process for removing oxygen-containing organic compounds from mixtures of hydrocarbon compounds, in which a liquid phase (1) containing hydrocarbons and oxygenates is charged to a first column (3), a light fraction is separated as top product (5) by distillation, and that a heavier C4+ fraction is removed from the bottom, the light fraction (5) and a gaseous mixture of hydrocarbons and oxygenates (2) is charged to a second column (7), and separated into a light and a heavy hydrocarbon fraction distillation, and an additional solvent (6) is supplied to the upper part of the second column (7), which dissolves the oxygenates and, the solvent and oxygenates being discharged as bottom product (9) and a hydrocarbon product (8), which is free from oxygenates leaves the top of the column (7). The solvent optionally is wholly or partly regenerated and recirculated to the extractive distillation column.

Abstract: The invention relates to a process for obtaining aromatic hydrocarbons selected from benzene, toluene, xylene and ethylbenzene mixtures thereof from a hydrocarbon mixture which additionally comprises nonaromatic hydrocarbons and high boilers, comprising the steps of (A) providing a hydrocarbon mixture a1 and an extractive solvent a2 composed of N-formylmorpholine, (B) extractively distilling the hydrocarbon mixture a1 with the extractive solvent to obtain a mixture b1 of extractive solvent and the aromatic hydrocarbons, said mixture comprising high boilers, and a mixture b2 comprising nonaromatic hydrocarbons, (C) distilling the mixture b1 of extractive solvent and aromatic hydrocarbons obtained in step (B) to obtain one or more fractions c1 composed of aromatic hydrocarbons and the extractive solvent c2 which comprises high boilers, (D) removing a substream d1 from the extractive solvent c2 and recycling the extractive solvent c2 into the extractive distillation (B), (E) extracting the substream d1 of the ex

Abstract: The invention provides a method of extracting the hydrogen sulfide contained in a gas comprising aromatic hydrocarbons, wherein the following stages are carried out: a) contacting said gas with an absorbent solution so as to obtain a gas depleted in hydrogen sulfide and an absorbent solution laden with hydrogen sulfide, b) heating and expanding the hydrogen sulfide-laden absorbent solution to a predetermined temperature and pressure so as to release a gaseous fraction comprising aromatic hydrocarbons and to obtain an absorbent solution depleted in aromatic hydrocarbons, said temperature and pressure being so selected that said gaseous fraction comprises at least 50% of the aromatic hydrocarbons and at most 35% hydrogen sulfide contained in said hydrogen sulfide-laden absorbent solution, c) thermally regenerating the absorbent solution depleted in aromatic hydrocarbon compounds so as to release a hydrogen sulfide-rich gaseous effluent and to obtain a regenerated absorbent solution.

Abstract: Process for producing purified hydrocarbon gas from a gas stream comprising methane and acidic contaminants, which process comprises the steps cooling the gas stream by expansion to form a mixture comprising solid and/or liquid acidic contaminants and a vapour containing gaseous hydrocarbons and a reduced amount of acidic contaminants; separating the solid and/or liquid acidic contaminants from the first mixture, yielding partly purified gas; compressing the partly purified gas; and contacting the compressed partly purified gas with an absorbing liquid to yield the purified hydrocarbon gas.

Abstract: A catalytic distillation process for isomerizing and separating 1-alkenes from a mixed alkene stream. The process comprises contacting a mixed alkene stream comprising the 1-alkene and homologs thereof with a supported isomerization catalyst under isomerization/distillation conditions effective to convert at least a portion of the homologs to the 1-alkene, the isomerization/distillation conditions also being effective to produce a distillation overhead comprising a sufficient portion of the 1-alkene to drive isomerization of the homologs to the 1-alkene while maintaining the mixed alkene stream at least partially in liquid phase. The isomerization/distillation conditions are effective to recover a quantity of 1-alkene greater than an equilibrium quantity of 1-alkene recovered under isomerization conditions alone.

Abstract: A treatment for accelerating the settling of finely divided solids in hydrocarbon fluids, including adding to the hydrocarbon a sufficient settling amount of a combination of at least two of (a) a quaternary fatty ammonium compound, (b) a hetero-atom punctuated fatty polymer and (c) an alkylphenol-formaldehyde resin alkoxylate.

Abstract: A treatment for accelerating the settling of finely divided solids in hydrocarbon fluids, including adding to the hydrocarbon a sufficient settling amount of a combination of (a) a polyacrylic acid adducted alkylphenol-formaldehyde resin alkoxylate compound, and (b) an alkylphenol-formaldehyde resin alkoxylate having a molecular weight of about 500 to about 5,000.

Abstract: The present invention relates to the separation of olefins, diolefins and lower aromatics from mixed streams of hydrocarbons using ionic liquids in the absence of metal compounds. The present invention eliminates the metal complexes conventionally used in such separation and thus reduces the complexity of the process.

Abstract: The present invention relates to the separation of olefins, diolefins and lower aromatics from mixed streams of hydrocarbons using ionic liquids in the absence of metal compounds. The present invention eliminates the metal complexes conventionally used in such separation and thus reduces the complexity of the process.

Abstract: A process for separating a feed mixture comprising at least one aromatic hydrocarbon and at least one non-aromatic hydrocarbon by extractive distillation (ED) utilizing a solvent mixture comprising sulfolane and at least one co-solvent. The co-solvent is an alkyl sulfolane having from 4 to 8 carbon atoms per molecule. The solvent mixture is added to the top of the ED column, and the feed mixture is added at a point on the ED column that is lower than the point where the solvent mixture is added. Extractive distillation is performed, and the aromatic and non-aromatic hydrocarbons are separated.

Abstract: The present invention relates to the separation of diolefins from mixed streams of hydrocarbons using ionic liquids in the absence of metal compounds.

Abstract: This invention relates to a method for separating olefins and paraffins from oxygenates in a liquid hydrocarbon stream containing a high proportion of olefins, paraffins and oxygenates (mainly alcohols). Typically, the hydrocarbon stream is obtained from a Fischer-Tropsch process. The organic counter-solvent has a boiling point which is less than the boiling point of the most volatile alcohol in the hydrocarbon stream. A raffinate from the liquid-liquid extractor is passed to a distillation column. A bottoms product from the distillation column comprises olefins and paraffins, and the overhead product comprising solvents is recycled. An extract from the liquid-liquid extractor is sent to a stripping column, where a bottoms product containing pure alcohol is obtained. The overhead product containing counter-solvent is recycled.

Abstract: The present invention relates to the separation of diolefins, and lower aromatics from mixed streams of hydrocarbons using ionic liquids and metal complexes. The present invention provides a novel method to separate diolefins and lower aromatics from other hydrocarbyl streams which may contain small amounts of water.

Abstract: A process is disclosed which provides for the reduction of phenylacetylene levels in styrene monomer feedstreams, which process utilizes a normal styrene inhibitor additive, such as an hydroxylamine, injected into the styrene monomer feedstream immediately upstream of the phenylacetylene reduction reactor.

Abstract: An improved furfural extraction process for lube oil base-stock production from hydrocarbon oils containing aromatic type material by the addition of a solvent comprising of furfural and a co-solvent, said process being conducted in a continuous countercurrent extraction column that facilitates phase separation and increases the raffinate yield while maintaining the same raffinate quality measured by raffinate refractive index.

Abstract: A process for removing impurities from a hydrocarbon component or fraction comprises mixing, in a liquid-liquid extraction step, an impurity-containing liquid hydrocarbon component or fraction, as an impure liquid hydrocarbon feedstock, with an acetonitrile-based solvent. Thereby, at least one impurity is extracted from the hydrocarbon component or fraction into the solvent. There is withdrawn from the extraction step, as a raffinate, purified hydrocarbon component or fraction, while there is withdrawn from the extraction step, as an extract, impurity-containing solvent.

Abstract: A process is described for extracting carotenes from carotene-containing materials, in particular from fats and oils of biological origin, which provides for extraction of carotene-containing material with an extractant comprising at least one member selected from the group consisting of acetonitrile, N-methylpyrrolidone, N,Ndimethylformamide, N,N-dimethylacetamide, 4-formylmorpholine, 4-acetylmorpholine, 4-methylmorpholine, 4-phenylmorpholine.

Abstract: A process for separating a feed mixture comprising at least one aromatic hydrocarbon and at least one non-aromatic hydrocarbon by extractive distillation (ED) utilizing a solvent mixture comprising sulfolane and at least one co-solvent. The co-solvent is an alkyl sulfolane having from 4 to 8 carbon atoms per molecule. The solvent mixture is added to the top of the ED column, and the feed mixture is added at a point on the ED column that is lower than the point where the solvent mixture is added. Extractive distillation is performed, and the aromatic and non-aromatic hydrocarbons are separated.

Abstract: A system and/or process for decreasing the level of at least one organic fluoride present in a hydrocarbon mixture by first passing the hydrocarbon mixture to an eductor and educting into the hydrocarbon mixture a catalyst comprising a volatility reducing additive and hydrofluoric acid to produce a hydrocarbon-catalyst mixture, permitting the hydrocarbon-catalyst mixture to undergo a phase separation to produce a hydrocarbon phase having a lower concentration of at least one organic fluoride than the hydrocarbon mixture and to produce a catalyst phase, and withdrawing at least a portion of the hydrocarbon phase to thereby form a hydrocarbon product stream, are disclosed. In an alternate embodiment, a system and/or process for controlling the concentration of at least one organic fluoride and/or the RON of the hydrocarbon mixture by adjusting the amount of volatility reducing additive present in the catalyst are disclosed.

Abstract: A solution comprising a polar solvent and C.sub.60 in which the solubility of C.sub.60 is at least 2 mg/ml of solvent. The polar solvent has a low toxicity, high boiling point, high thermal and electrochemical stability, low viscosity, low freezing point, a high dielectric constant, and is relatively inexpensive. Preferably the polar solvent is N-ethyl-2-pyrrolidone.

Abstract: Disclosed is a process for recovering styrene from a feedstock containing at least styrene, ethylbenzene, and one or more aromatic or non-aromatic hydrocarbon compounds which includes separating said feedstock into a first stream relatively more concentrated in styrene than said feedstock and a second stream relatively more concentrated in ethylbenzene than said feedstock, recovering styrene from said first stream to produce a styrene product stream, dehydrogenating the ethylbenzene of said second stream to produce additional styrene, and recovering said additional styrene. The feedstock may be separated into said first and second streams by a process selected from the class consisting of extractive distillation, azeotropic distillation, distillation, liquid-liquid extraction, chemical complex formation, membrane separation, and combinations thereof, and the additional styrene may be recovered by recycling it into said feedstock.

Abstract: An extractive distillation process for separating at least one substituted unsaturated aromatic from a pyrolysis gasoline mixture, containing said aromatic and at least one close-boiling aromatic or non-aromatic hydrocarbon, employing a two part extractive solvent, the first part selected from propylene carbonate, sulfolane (tetramethylene sulfone), methyl carbitol, 1-methyl-2-pyrrolidinone, 2-pyrrolidinone and mixtures thereof, and the second portion consisting of water.

Abstract: Benzene is difficult to separate from cyclohexane or cyclohexene by conventional distillation or rectification because of the close proximity of their boiling points. Benzene can be readily separated from cyclohexane or cyclohexene by using extractive distillation. Effective agents are: for benzene from cyclohexane, methyl acetoacetate; for benzene from cyclohexene, ethyl acetoacetate.

Abstract: Heptane is difficult to separate from 1-heptene by conventional distillation or rectification because of the proximity of their boiling points. Heptane can be readily separated from 1-heptene by extractive distillation. Effective agents are diacetone alcohol, ethyl butyrate and dimethylsulfoxide.

Abstract: 1-Decene is impossible to separate from 2-octanone by conventional distillation or rectification because the two compounds form a minimum boiling azeotrope. 1-Decene can be readily separated from 2-octanone by azeotropic distillation. Effective agents are 1-propanol, 2-ethoxyethanol, and methanol.

Abstract: Benzene and other aromatics are separated from a stream of mixed hydrocarbons containing both aromatics and non-aromatics by extractive distillation with a solvent system containing dimethyl sulfoxide and optionally a co-solvent, preferably water, followed by distillation stripping of the aromatics from the enriched solvent system, and recycle of the lean solvent system to the extractive distillation step.

Abstract: Hexane is difficult to separate from vinyl acetate and/or methyl acrylate by conventional distillation or rectification because of the closeness of their boiling points. Hexane can be readily separated from vinyl acetate and/or methyl acrylate by extractive distillation. Effective agents are dimethylsulfoxide and dimethylformamide.

Abstract: alpha-Phellandrene is difficult to separate from d-limonene by conventional distillation or rectification because of the proximity of their boiling points. alpha-Phellandrene can be readily separated from d-limonene by azeotropic distillation. Effective agents are n-butyl acetate and sulfolane.

Abstract: 1-Octene is difficult to separate from octane by conventional distillation or rectification because of the proximity of their boiling points. 1-Octene can be readily separated from octane by azeotropic distillation. Effective agents are ethyl formate, ethyl acetate and t-amyl methyl ether.

Abstract: alpha-Phellandrene is difficult to separate from 3-carene by conventional distillation or rectification because of the proximity of their boiling points. alpha-phellandrene can be readily separated from 3-carene by azeotropic distillation. Effective agents are methyl formate, nitroethane and acetal.

Abstract: Heptane cannot be removed from heptane-vinyl acetate mixtures by distillation because of the minimum boiling azeotrope. Heptane can be readily removed from vinyl acetate by extractive distillation. Typical effective agents are dimethylsulfoxide, phenol, diisobutyl ketone and hexyl acetate.

Abstract: Octene-1 is difficult to separate from several of its isomers by conventional distillation or rectification because of the closeness of their boiling points. Octene-1 can be readily separated from its close boiling isomers by azeotropic or extractive distillation. Effective agents are: for azeotropic distillation, t-amyl methyl ether; for extractive distillation, isophorone.

Abstract: Heptane cannot be separated from vinyl acetate by conventional distillation or rectification because of the minimum boiling azeotrope. Heptane can be readily separated from vinyl acetate by using azeotropic distillation. Typical examples of effective agents are methyl acetate, ethanol, ethyl formate or t-amyl methyl ether.

Abstract: Hexane cannot be separated from vinyl acetate by conventional distillation or rectification because of the minimum boiling azeotrope. Hexane can be readily separated from vinyl acetate by using azeotropic distillation. Typical examples of effective agents are acetone, acetonitrile or methyl t-butyl ether.

Abstract: The method of obtaining a pure aromatic hydrocarbon from a hydrocarbon starting mixture includes extractively distilling the hydrocarbon starting mixture with a selective solvent; feeding the sump product of the extractive distillation through a first and second auxiliary boilers connected in series to form a cooled sump product at a temperature from 105.degree. to 120.degree. C.

Abstract: Hexane cannot be removed from hexane--vinyl acetate--methyl acrylate mixtures because of the ternary azeotrope. Hexane can be readily removed from hexane--vinyl acetate--methyl acrylate mixtures by extractive distillation. Typical effective agents are phenol, diethylene glycol methyl ether and 2-nitropropane.

Abstract: The present invention is directed to a process for removal of sulfur contaminants from hydrocarbons using processes which rely upon the reaction of organosulfur compounds with N-halogeno compounds. The sulfur removal may be effected by using liquid/liquid extraction processes or one of two reactive adsorption processes involving injecting a stoichiometric amount of N-halogeno compounds into hydrocarbon and then passing the stream through an adsorbent column to adsorb the N-halogeno-sulfur compounds and any unreacted N-halogeno compounds; or using adsorbents which are pre-loaded with N-halogeno compounds which are placed in a fixed-bed column for sulfur removal.

Abstract: For recovery of low-boiling hydrocarbons by scrubbing, the crude gas mixture which contains low-boiling and high-boiling hydrocarbons, is treated with a scrubbing agent, by which the high-boiling components are scrubbed-out of the gas mixture. The loaded scrubbing agent, with the addition of liquid medium miscible with the scrubbing agent and which reduces the solubility for the scrubbed-out hydrocarbons, is regenerated and the completely regenerated scrubbing agent is recycled to the scrubbing. The regeneration is preferably divided into the following individual steps:(a) stripping of the loaded scrubbing agent, optionally with addition of medium,(b) addition of the liquid medium to partially regenerate scrubbing agent, decanting of the split phases,(c) stripping of the resultant decanted scrubbing agent/medium mixture, and(d) rectifying the scrubbing agent/medium mixture to separate the scrubbing agent.

Abstract: An extractive distillation process for separating at least one C.sub.4 -C.sub.10 alkene (monoolefin) from at least one close-boiling alkane employs solvent at least one N-mercaptoalkyl-2-pyrrolidone, preferably N-(.beta.-mercaptoethyl)-2-pyrrolidone, optionally in admixture with at least one N-alkyl-2-pyrrolidone, preferably N-methyl-2-pyrrolidone.

Abstract: Meta and para-diisopropylbenzenes cannot be easily separated from each other by distillation because of the closeness of their vapor pressures. m-Diisopropylbenzene can be readily removed from p-diisopropylbenzene by azeotropic distillation using certain nitrogenous compounds. Typical effective azeotropic distillation agents are ethanolamine and benzonitrile.

Abstract: A process for recovering pure benzene from hydrocarbon mixtures containing the same and non-aromatic compounds which are gaseous and difficultly condensible is described in which the feedstock is fed to an initial distillation column operated at atmospheric or sub-atmospheric pressure. Overhead comprising benzene and non-aromatics is obtained and a portion thereof condensed. The condensible material is in part returned to the distillation column and in part subjected to extractive distillation to recover pure benzene. Those components which did not condense, i.e. the non-condensible and difficultly condensible components and entrained aromatics are fed to a reflux vessel such as a scrubber, stripper, or the like for recovery of any benzene or other valuable components which might be soluble in a selective solvent and used for such recovery. The selective solvent can be the same solvent used for the extractive distillation.

Abstract: A process of recovering an n-hexane product which is free from aromatic compounds by extractive distillation from a mixture of aromatic and non-aromatic compounds. The mixture is fed to and distilled in a first distillation column, from which a benzene-containing sump product and the overhead product consisting of non-aromatic compounds are withdrawn. The distillate is laterally withdrawn above the feeding point of the feed mixture and transferred to the upper portion of a second distillation column. The hexane cut is withdrawn as sump product from the second distillation column and fed to an extractive distillation column approximately in the middle thereof and is extracted in the extractive distillation column with a selective solvent which is fed above the feeding point of the hexane cut consisting of the sump product of the second distillation column. The sump product containing the selective solvent is withdrawn from the extractive distillation column and the overhead thereof vapors are condensed.

Abstract: A process for isolating a conjugated diolefin from a C.sub.4 - or C.sub.5 -hydrocarbon mixture containing the diolefin, by single-stage or multi-stage extractive distillation using a selective solvent, wherein the selective solvent is a solvent mixture which comprises(a) from 1 to 99 percent by weight of an N-alkyl-substituted lower aliphatic acid amide or of an N-alkyl-substituted alicyclic acid amide having 5 ring members and(b) from 1 to 99 percent by weight of an aliphatic or alicyclic ether boiling at from 30.degree. C. to 200.degree. C.