Abstract: 1,1,1-Trichloroethane cannot be completely separated from n-hexane by conventional distillation or rectification because of the minimum boiling azeotrope. 1,1,1-Trichloroethane can be readily separated from n-hexane by extractive distillation. Typical effective agents are: methyl isoamyl ketone, amyl acetate and isobutanol.

Abstract: The separation of aromatic hydrocarbons from mixtures of aromatic and non-aromatic hydrocarbon feeds under pervaporation conditions, is improved by the control of the amount of oxygen present in the feed. The amount of oxygen in the feed, such as heavy cat naphtha or other cracked feed, should be less than 30 wppm, preferably less than 10 wppm. The oxygen level in the feed can be controlled by the addition of small amount of oxygen scavenger into the feed. Hindered phenols are representative of useful oxygen scavengers.

Abstract: m-Xylene is difficult to separate from p-xylene or o-xylene by conventional distillation or rectification because of the close proximity of their boiling points. m-Xylene can be readily separated from p-xylene or o-xylene by using extractive distillation in which the agent is an alcohol. Typical examples of effective agents are: for m-xylene from o-xylene, 1-octanol and cyclododecanol; for p-xylene from m-xylene, diisobutyl carbinol and cyclododecanolphenethyl alcohol mixture.

Abstract: An extractive distillation process for separating at least one aromatic hydrocarbon from at least one close-boiling alkane employs as solvent a mixture of (a) at least one N-mercaptoalkyl-2-pyrrolidone, preferably N-(.beta.-mercaptoethyl)-2-pyrrolidone and (b) at least one sulfolane, preferably cyclotetramethylene sulfone.

Abstract: Cyclohexane cannot be readily separated from cyclohexene by conventional distillation or rectification because of the close proximity of their boiling points. Cyclohexane can be separated from cyclohexene by azeotropic or extractive distillation. Typical examples of effective agents are: for azeotropic; ethylene glycol methyl ether and n-butanol; for extractive; propylene glycol methyl ether and diacetone alcohol.

Abstract: A process for separating 2,6-dimethylnaphthalene form a 2,6-dimethylnaphthalene-containing mixture which comprises mixing said mixture with 2,4,7-trinitro-9-fluorenone to thereby form a complex, separating a solid matter containing said complex and decomposing the solid matter containing the same to thereby separate and collect an oil rich in the 2,6-dimethylnaphthalene. According to this process, 2,6-dimethylnaphthalene can be readily separated at a high selectivity. Further, the 2,4,7-trinitro-9-fluorenone can be readily recovered and reused as such.

Abstract: Cycloalkanes, preferably cyclohexane and/or cyclopentane, are separated from close-boiling alkanes by extractive distillation employing as solvent a mixture of (a) at least one N-hydroxyalkyl-2-pyrrolidone, preferably N-(.beta.-hydroxyethyl)-2-pyrrolidone, and (b) at least one saturated C.sub.5 -C.sub.9 alcohol, preferably cyclohexanol.

Abstract: Extractive distillation processes for separating aromatic hydrocarbon(s) or cycloalkane(s) or alkene(s) from close-boiling alkane(s) are carried out with a solvent including at least one N-alkyl-2-thiopyrrolidone compound, preferably N-methyl-2-thiopyrrolidone. Optionally, the solvent additionally contains a cosolvent, preferably tetraethylene glycol or N-(.beta.-mercaptoethyl)-2-pyrrolidone or unsubstituted sulfolane.

Abstract: Disclosed is a method for cracking a hydrocarbon material. The method includes introducing a stream including a hydrocarbon fluid into a reaction zone. A microwave discharge plasma is continuously maintained within the reaction zone, and in the presence of the hydrocarbon fluid. Reaction products of the microwave discharge are collected downstream of the reaction zone.

Abstract: In the method for the production of an aromate concentrate suitable for use as blending component for gasifier fuel, feed hydrocarbon mixtures having boiling ranges substantially between 40.degree. and 170.degree. C., are subjected, without any previous separation into individual fractions, to an extractive distillation employing N-substituted morpholine, substituents of which display no more than seven C-atoms, as selective solvent. Herewith, the lower boiling non-aromates with a boiling range up to about 105.degree. C., practically completely, and most of the higher boiling non-aromates with a boiling range between about 105.degree. and 160.degree. C., are recovered as raffinate, whereas the aromates, which are to be employed in whole or in part as blending component, come down in the extract of the extractive distillation.

Abstract: Gasoline octane number and yield are improved while excess fuel gas production is decreased in a catalytic cracking process by integrating etherification and oxygenate/aliphatic upgrading processes into the catalytic cracking unit product fractionation section.

Abstract: A process for separating 2,6-dimethylnaphthalene from a 2,6-dimethylnaphthalene-containing mixture which comprises mixing said mixture with a complexing agent selected from the group consisting of bis(1,2,5)thiaziazolotetracyanoquinodimethane, (1,2,5)selenadiazotetrocyanonaphthoquinodimethane, (1,2,5)thiaziazolotetracyanonaphthoquinodimethane, 2,6-dichlorotetracyanoanthraquinodimethene, and 2,6-diiodotetracyanoanthraquinodimethane to thereby form a complex, separating a solid matter containing said complex; and decomposing the solid matter containing the same to thereby separate and collect an oil rich in the 2,6-dimethylnaphthalene. According to this process, 2,6-dimethylnaphthalene can be readily separated at a high selectivity. Further the complexing agent can be readily recovered and reused as such.

Abstract: The hydrogen sulfide content of the atmosphere over sour heavy fuel oils is controlled by the addition of choline to the fuel oil.

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: There is disclosed a process for treating liquid (liquifiable) and gaseous hydrocarbons to remove substantially all of the acid gases including COS by contacting the hydrocarbon streams with specific aqueous treating agents in a series of sequential specific limit operations and apparatus.

Abstract: A process is disclosed for the separation of aromates from hydrocarbon mixtures of optional aromate content through extractive distillation using N-substituted morpholine displaying substituents having no more than 7 C-atoms as selective solvent. Part of the solvent is delivered to the uppermost plate of the extractive distillation column and the remainder of the solvent, preferably amounting to between 10 and 40% by weight, is introduced into the extractive distillation column in at least two partial streams onto plates above the inlet for the hydrocarbon mixture. The temperature of the respective solvent partial streams is adjusted to neither exceed the temperature of the corresponding delivery plates nor fall below this temperature by more than 10.degree. C.

Abstract: A process for removing oxygenated impurities from a hydrocarbon stream includes extracting said oxygenates by a heavy organic polar solvent, water scrubbing the extracted hydrocarbon to recover dissolved solvent and combining the solvent phase from the extractor and the water phase from the scrubber and distilling to recover the solvent.

Abstract: A process for separating a butene-1/isobutene mixture from a C.sub.4 hydrocarbon fraction is provided which comprises subjecting the C.sub.4 hydrocarbon fraction to extractive distillation using a polar solvent to separate components predominantly containing 1,3-butadiene as an extract and obtain an overhead containing butanes, butene-1, isobutene and butene-2 as main components and being substantially free from C.sub.3 -C.sub.4 diolefinic and acetylenic hydrocarbons, feeding the overhead into a first distillation column, removing isobutane as an overhead component from the first distillation column, feeding high-boiling components from the bottom of the first distillation column to a second distillation column, removing n-butane and butene-2 from the bottom of the second distillation column, and obtaining highly pure butene-1 and isobutene from its top.

Abstract: A process for separating a butene-1/isobutene mixture from a C.sub.4 hydrocarbon fraction is provided which comprises subjecting the C.sub.4 hydrocarbon fraction to extractive distillation using a polar solvent to separate components predominantly containing 1,3-butadiene as an extract bottom and obtain an overhead containing butanes, butene-1, isobutene and butene-2 as main components and being substantially free from C.sub.3 -C.sub.4 diolefinic and acetylenic hydrocarbons, feeding the overhead into a first distillation column, removing n-butane and butene-2 as bottoms from the column, feeding low-boiling components from the top of the column into a second distillation column, removing isobutane from the top of the second distillation column, and obtaining highly pure butene-1 and isobutene from its bottom.

Abstract: A process for separating highly pure butene-2 and butene-1 from a C.sub.4 hydrocarbon fraction containing isobutane, n-butane, butene-1, butene-2, and at least one diolefinic hydrocarbon and/or at least one acetylenic hydrocarbon, which comprises, (1) as a step A, treating the C.sub.

Abstract: A process and apparatus are provided controlling the heat input of an extractive distillation column. The bottom of the column is heated with a major stream of thermal energy which is either slowly varying in time or controlled by the amount of starting material mixture and with a minor stream of thermal energy which is controlled by sensing the thermodynamic state in the upper half of the column during the process. The major stream can provide about 90 percent and the minor stream about 10 percent of the heat fed to the column. The minor stream can be controlled by the temperature at one point in the upper half of the column, by the temperature difference at two points in the upper half of the column or by gas chromatographic analysis of the extract material concentration near the top of the column. The process allows one to keep a low concentration of the extract material in the raffinate.

Abstract: This invention is directed to the use of mixtures of a polymerization inhibitor in the distillation of readily polymerizable vinyl aromatic monomers and more specifically to the use of mixtures containing 2,6-dinitro-4-halophenols as polymerization inhibitors for vinyl aromatic monomers such as styrene and vinyl benzenes. The invention comprises the process of subjecting the vinyl aromatic monomers to distillation temperatures in the presence of mixtures containing 2,6-dinitro-4-halophenols to inhibit polymerization.

Abstract: This invention is directed to the use of a polymerization inhibitor in the distillation of readily polymerizable vinyl aromatic monomers and more specifically to the use of mixtures of 2,6-dinitro-4-ethyl-phenol as a polymerization inhibitor for vinyl aromatic monomers such as styrene and vinyl benzenes. The invention comprises the process of subjecting the vinyl aromatic monomers to distillation temperatures in the presence of mixtures of 2,6-dinitro-4-ethyl-phenol and 2,6-dinitro-paracresol to prevent polymerization.

Abstract: The present invention provides an improvement in methods for preparing and processing ethylenically unsaturated aromatic monomer. The improvement comprises employing 3,5-dinitrosalicylic acid or a derivative or isomer thereof as a process inhibitor. The process inhibitor is present in a concentration of about 50 to 3000 ppm, preferably about 250 to 2,000 ppm, and most preferably about 500 to 1,000 ppm.

Abstract: Aromatic hydrocarbons are separated from a mixture thereof with paraffinic hydrocarbons by solvent extraction with N-(2-hydroxyethyl)-2-pyrrolidone containing a minor amount of water at specified elevated temperatures and pressures. Temperature variations within the specified range have little effect on the loading capacity and selectivity of the solvent thus greatly simplifying process control.

Abstract: Isoprene and butadiene are purified by treating a petroleum refinery C.sub.4 stream or petroleum refinery C.sub.5 stream which contain butadiene or isoprene or relatively pure butadiene or isoprene and carbon disulfide by treatment of these streams with from about 1 to about 7 equivalents of a polyamine. The polyamine reacts with the CS.sub.2 impurity to form the dithiocarbamate salt. The hydrocarbon is then separated from the dithiocarbamate salt and any excess unreacted polyamine by water washing this stream or by flash distilling of the hydrocarbon.

Abstract: Process for removing halogenated impurities from olefin oligomers by extraction with a polar solvent such as dimethylsulfoxide, acetonitrile, dimethylacetamide, dimethylformamide, diethylene glycol or dimethylsulfone.

Abstract: The present invention provides an improvement in methods for preparing and processing ethylenically unsaturated aromatic monomer. The improvement comprises employing 3,5-dinitrosalicylic acid as a process inhibitor. The DNSA is present in a concentration of about 50 to 3000 ppm, preferably about 250 to 2000 ppm, and most preferably about 500 to 1000 ppm.

Abstract: Liquid salts such as quaternary phosphonium and ammonium salts of halides, acids, or more complex anions can be utilized to extract aromatics from mixed aliphatic/aromatic hydrocarbon feeds such as isomerization process feed streams, cat naphthas, lube stocks, and the like. Such salts show the required solubilities in various solvents to exhibit a distinct selectivity advantage over more commonly used extraction solvents such as sulfolane in the extraction of benzene and other aromatics from heptane and other aliphatic feedstreams.

Abstract: Separation of benzene from cyclohexane by distillation in the presence of selected nitriles.

Abstract: In processes in which liquid sorbents that are solutions in an aromatic hydrocarbon or halogenated aromatic hydrocarbon of a bimetallic salt complex having the generic formula M.sub.I M.sub.II X.sub.n.Aromatic, wherein M.sub.I is a Group I-B metal, M.sub.II is a Group III-A metal, X is halogen, n is the sum of the valences of M.sub.I and M.sub.II, and Aromatic is a monocyclic aromatic hydrocarbon or halogenated aromatic hydrocarbon are used to separate complexible ligands from a gas feedstream that comprises an olefin having 2 or 3 carbon atoms, alkylation of the aromatic hydrocarbon or halogenated aromatic hydrocarbon is inhibited by incorporating in the liquid sorbent from 8.5 mole percent to 30 mole percent, based on the Group I-B metal in the liquid sorbent, of an amine-aluminum chloride adduct, such as ammonia-aluminum chloride adduct or pyridine-aluminum chloride adduct.

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: Entrained phosphoric acid contained in isopropylbenzene alkylate from a solid phosphoric acid-catalyzed process wherein benzene is alkylated with propylene is neutralized and rendered soluble in the alkylate by the addition to the alkylate stream of a primary amine.

Abstract: Formation of butadiene-1,3 polymer during the extractive distillation of a C-4 hydrocarbon mixture to separate and purify butadiene-1,3 using a solvent composition in which an alkoxynitrile is present in a proportion of 50-99 percent by weight, is decreased through inclusion in the solvent of a synergistic combination of 2,4-dinitrophenol and phosphoric acid, each in a proportion of 0.05 to 0.5 percent by weight.

Abstract: A process for isolating butadiene by means of a selective solvent from a C.sub.4 -hydrocarbon mixture which contains butadiene, small amounts of oxygen, hydrocarbons which are more soluble than butadiene in the selective solvent and hydrocarbons which are less soluble than butadiene in the selective solvent, wherein the C.sub.4 -hydrocarbon mixture is separated, by extractive distillation, into a distillate containing the less soluble hydrocarbons, a stream of butadiene and a stream containing the more soluble hydrocarbons, a mixture of oxygen and C.sub.4 -hydrocarbons is separated out of the C.sub.4 -hydrocarbon mixture in a distillation zone upstream of the extractive distillation, and the bottom product is fed to the extractive distillation.

Abstract: A method for the removal of carbonyl sulfide from liquid propane under liquid-liquid contact conditions by mixing liquid propane containing carbonyl sulfide as an impurity with 2-(2-aminoethoxy) ethanol as the principal agent for the carbonyl sulfide removal. The 2(2-aminoethoxy) ethanol is reclaimed and reused for further carbonyl sulfide removal.

Abstract: In order to prevent corrosion of the apparatus in extraction and extractive distillation processes where N-substituted morpholine is employed as the selective solvent an additive is added to the solvent which additive consists of (a) phosphoric acid, (b) a salt thereof, (c) a vanadium compound, (d) a molybdenum compound or (e) a mixture of two or more of these compounds, the addition being effected in an amount of about 0.005 to 0.02% by weight of the morpholine solvent.

Abstract: A process for separating, by means of a selective solvent, a mixture of C.sub.