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: A method for removing diethylhydroxylamine (DEHA) from butadiene streams that does not leave an excessive amount of residual contaminates in the isolated butadiene stream. The DEHA is removed from the butadiene streams by ion exchange resins, which efficiently remove DEHA from the butadiene streams without causing the accumulation of an excessive amount of residual contaminants. To prevent polymerization of the butadiene upon removal of the DEHA, tert-butylcatechol (TBC) may be added to the butadiene stream before or after DEHA removal. Fresh or spent ion exchange resins may be used. After removal from the butadiene stream, the isolated DEHA can then be easily concentrated, and disposed or recycled. A method for removing DEHA from hydrocarbon streams is also disclosed.

Abstract: A mixture (M1) comprising an alkene and oxygen is worked up by a process in which (i) oxygen is removed from the mixture (M1) by a nondistillative method to give a mixture (M2) and (ii) the alkene is separated off from the mixture (M2) by distillation.

Abstract: Process for the high-yield recovery of ethylene and heavier hydrocarbons from the gas produced by pyrolysis of hydrocarbons (1) in which the liquid products (12-15, 23) resulting from the fractionated condensation of the cracking gas (1) for the recovery of almost all the ethylene, are supplied to a distillation column (C1), called the de-ethanizer, at different intermediate levels, at the top of which the vapor (31) of the column distillate is treated directly in an acetylene hydrogenation reactor (R1), the effluent containing virtually no acetylene being separated by a distillation column (C2) called the de-methanizer, into an ethylene- and ethane-enriched tail product (43), while the head product (44) is recycled by compression or treated for subsequent recovery of ethylene.

Abstract: Apparatus, methods and systems useful for removing phenylacetylene from crude styrene feedstock are disclosed. Generally the processes and systems comprise the catalytic reduction of phenylacetylene to produce styrene via injection of a phenylacetylene reducing agent, such as hydrogen. A phenylacetylene reduction catalyst preferred herein comprises palladium on a calcium aluminate carrier, wherein the catalyst comprises less than 0.3 weight percent palladium.

Abstract: The present invention relates to a method for separating a lactone-containing high-molecular weight compound having an alkyl group as its side chain from a lactone-containing high-molecular weight compound having an alkenyl group as its side chain by using a sulfonic acid group-containing cation exchange resin pretreated with silver ions.

Abstract: The invention relates to a process for the selective recovery of olefins from a mixture of gases by: a) bringing a gaseous mixture having olefins and hydrogen into contact with silver nitrate solution whereby the olefins are absorbed into the silver nitrate solution as a complex; b) separating the solution having complexed olefins from the non-absorbed gases; c) depressurising and heating the olefin complex solution from (b) so as to release the olefins from the complex and regenerate the silver nitrate solution; d) passing the regenerated silver nitrate solution through a bed containing silver oxide so as to maintain the pH value of the silver nitrate at between 3 and 6; and e) recycling the silver nitrate solution regenerated in (d) to step (a).

Abstract: The invention relates to a process for the recovery as a feedstock of an alpha-olefin from a mixture containing mainly hydrocarbon compounds, such as is obtained by Fischer-Tropsch-synthesis after an at least crude separation of components boiling higher and/or lower than the alpha-olefin, wherein tertiary olefins of the mixture, after superstoichiometrical addition of a low alcohol, are subjected to catalytic etherification and a stream derived by etherification is fed jointly with the alpha-olefin and the ethers produced and other high boiling reaction products to a distillative separation of components boiling higher than the olefin.

Abstract: The invention is a process for recovering heat and removing impurities from a reactor effluent stream withdrawn from a fluidized exothermic reaction zone for conversion of oxygenates into light olefins from an oxygenate feedstream. The process comprises a two-stage quench tower system to remove water from the reactor effluent stream in the first tower and recover heat from the reactor effluent to at least partially vaporize the feedstream by indirect heat exchange between the oxygenate feedstream and either a first stage overhead stream or a first stage pumparound stream. A drag stream withdrawn from the first tower comprises the majority of the impurities and higher boiling oxygenates. The second stage tower further removes water and provides a purified water stream which requires minimal water stripping to produce a high purity water stream. The invention concentrates the impurities into a relatively small stream and results in significant energy and capital savings.

Abstract: An improved process for the production and purification of unsaturated monomers employing nitroxyl-containing inhibitors wherein process streams containing the inhibitor are recycled is disclosed, wherein the improvement comprises recycling said streams at a reboiler temperature no higher than about 110° C.

Abstract: A process is provided for the concentration and recovery of ethylene and heavier components from an oxygenate conversion process. A separation process such as a pressure swing adsorption (PSA) process is used to remove hydrogen and methane from a demethanizer overhead stream comprising hydrogen, methane and C2 hydrocarbons and subsequently return the recovered C2 hydrocarbons to be admixed with the effluent from the oxygenate conversion process. This integration of a separation zone with a fractionation scheme in an ethylene recovery scheme using an initial demethanizer zone resulted in significant capital and operating cost savings by the elimination of cryogenic ethylene-based refrigeration from the overall recovery scheme.

Abstract: Disclosed is a method for recovering olefin in an oxygenate to olefin production process. The method includes reacting a stream containing olefin with water in the presence of a hydrating catalyst to produce an alcohol containing stream. The alcohol containing stream can be used as an oxygenate feed in the oxygenate to olefin production process.

Abstract: An extractive distillation tower 4 supplied with a feedstock containing butadiene and a solvent and for distilling the feedstock to separate and purify the butadiene.

Abstract: Ethylene is a commodity chemical used as a reactant in the production of vinyl acetate. Ethylene is relatively expensive thus making its recovery and re-use in the process encouraged. The present invention provides a method for the recovery of ethylene from the inert gas purge stream from the reactor loop in a vapor-phase process for making vinyl acetate. The method of the present invention includes the steps of contacting the inert gas purge stream containing ethylene with acetic acid in an absorption vessel; discharging a stream containing acetic acid and ethylene from one aspect of the absorption vessel; separating the ethylene from the acetic acid in the stream by contacting the stream with ethylene gas in a scrubber column; and recovering ethylene from a top portion of the scrubber column. The method may also include the step of recycling the recovered ethylene to the reactor loop for further use.

Abstract: A process for the isolation of high-boiling monomers from distillation residue formed in the cyclodimerization and/or cyclotrimerization of 1,3-butadiene after target products of cyclooctadiene, vinylcyclohexene and/or cyclododecatriene have been separated off, comprising extracting the distillation residue with a nonpolar or slightly polar solvent, separating off insoluble oligomers and polymers that have at least partly crystallized by mechanical separation, removing the extractant, and isolating the high-boiling monomers.

Abstract: The present invention provides a method for recovering high purity olefins from cracked gas effluents or other paraffin/olefin gaseous mixtures by use of a chemical absorption process.

Abstract: Ethylene is a commodity chemical used as a reactant in the production of vinyl acetate. Ethylene is relatively expensive thus making its recovery and re-use in the process encouraged. The present invention provides a method for the recovery of ethylene from the inert gas purge stream from the reactor loop in a vapor-phase process for making vinyl acetate. The method of the present invention includes the steps of contacting the inert gas purge stream containing ethylene with acetic acid in an absorption vessel; discharging a stream containing acetic acid and ethylene from one aspect of the absorption vessel; separating the ethylene from the acetic acid in the stream by contacting the stream with ethylene gas in a scrubber column; and recovering ethylene from a top portion of the scrubber column. The method may also include the step of recycling the recovered ethylene to the reactor loop for further use.

Abstract: The invention pertains to a process of removing dienes from an olefin feedstock. A preferred olefin feedstock is for the production of primary alcohol compositions by skeletal isomerization of the olefins followed by hydroformylation. In this preferred embodiment, the olefin feedstock may be purified before and/or after skeletal isomerization. The olefins in the feedstock preferably have a carbon chain length of about 8 to about 36 carbon atoms, preferably about 10 to about 20 carbon atoms, most preferably about 12 to about 18 carbon atoms.

Abstract: A process for the rejection of heavy reaction by-products from a selective hydrogenation reaction zone effluent containing butadiene and trace amounts of heavy reaction by-products by introducing the selective hydrogenation reaction zone effluent into a butadiene extraction vaporizer containing a fractionation zone, refluxing the fractionation zone with a raffinate stream from a butadiene extraction zone; removing a vaporized stream containing butadiene and having a reduced concentration of heavy reaction by-products from the vaporizer; removing and recovering a concentrated liquid product stream containing heavy reaction by-products from the vaporizer; and introducing the vaporized stream containing butadiene into the butadiene extraction zone.

Abstract: Bromine reactive hydrocarbon contaminants are removed from aromatic streams by first providing an aromatic feedstream having a negligible diene level. The feedstream is contacted with an acid active catalyst composition under conditions sufficient to remove mono-olefins. An aromatic stream may be pretreated to remove dienes by contacting the stream with clay, hydrogenation or hydrotreating catalyst under conditions sufficient to substantially remove dienes but not mono-olefins.

Abstract: A process for isolating isobutene from a hydrocarbon mixture by a) combining the C4-hydrocarbon mixture with a primary C3- or C4-alkanol; b) reacting the isobutene in the C4-hydrocarbon mixture with the primary C3- or C4-alkanol in the presence of a heterogeneous catalyst to give the corresponding tertiary ether of isobutene, c) separating the resultant reaction mixture into the relatively low-boiling, unetherified C4-hydrocarbons and the relatively higher-boiling tertiary ether of isobutene with the aid of a distillation column, where the C4-hydrocarbons are taken off at the top, and the tertiary ether of isobutene obtained at the bottom is transferred into a reactor, d) cleaving this ether into isobutene and the corresponding primary C3- or C4-alkanol, e) distilling this mixture from d) in a further distillation column, and taking off the isobutene as the top product, which comprises carrying out step a) in a zone (4C) containing reactive internals and containing the catalyst for carrying out step b)

Abstract: A process and a device for separating ethane and ethylene from a hydrocarbon steam-cracking effluent is described. Effluent (1) is absorbed in an absorption column (7) by a cooled solvent (9). At the bottom of the column, liquid phase (12) that contains the solvent and the C2+ hydrocarbons is recovered and hydrogenated (15). The hydrogenation effluent that contains the solvent is introduced into a first distillation column (70) where the solvent is regenerated. The solvent is cooled and recycled at the top of absorption column (7). The C2+ hydrocarbons are collected at the top, and a condensed liquid phase is distilled in a second distillation column (77) to recover a C2 fraction that consists of ethane and ethylene.

Abstract: The invention relates to a process for purifying hydrocarbon vapor consisting of at least one aromatic or one olefinic or one paraffinic compound or of a mixture thereof, this hydrocarbon vapor entraining impurities of acid or alkaline nature which consist of at least one water-soluble organic and/or inorganic substance and it also relates to a facility for performing such a process.

Abstract: This invention relates to a process for separating and isolating olefins from saturated hydrocarbons, and in particular, to a process for separating and isolating olefins from saturated hydrocarbons in a Fisher-Tropsch stream.

Abstract: A process for separating ethane and ethylene from a hydrocarbon steam-cracking effluent is described. Effluent (1) is absorbed in an absorption column by a cooled solvent (9). At the bottom of the column, the liquid phase that contains the solvent and the C2+ hydrocarbons is recovered and hydrogenated (15). The hydrogenation effluent that contains the solvent is introduced into a first distillation column (16). Ethane-ethylene mixture (17) is drawn off laterally from the column, and a phase (19) that contains the solvent and hydrocarbons with at least 3 carbon atoms is drawn off at the bottom of the column. This phase (19) is separated in a second distillation column (22), and C3+ hydrocarbons and, at the bottom of the column, regenerated solvent (26) that is cooled and that is recycled (9, 52) in the absorption column are collected.

Abstract: A process is provided for the concentration and recovery of ethylene and heavier components from an oxygenate conversion process. A separation process such as a pressure swing adsorption (PSA) process is used to remove hydrogen and methane from a demethanizer overhead stream comprising hydrogen, methane and C2 hydrocarbons and subsequently return the recovered C2 hydrocarbons to be admixed with the effluent from the oxygenate conversion process. This integration of a separation zone with a fractionation scheme in an ethylene recovery scheme using an initial deethanizer zone resulted in significant capital and operating cost savings by the elimination of cryogenic ethylene-based refrigeration from the overall recovery scheme.

Abstract: Methods for separating olefins from non-olefins, such as parafins, including cycloparaffins, oxygenates and aromatics, are provided. The methods use metal salts to complex olefins, allowing the non-olefins to be separated by a variety of methods, including decantation and distillation. The metal salts are dissolved in ionic liquids, which tend to have virtually no vapor pressure, and which poorly solubilize the non-olefins. Accordingly, the non-olefins phase separate well, and can be distilled without carrying over any of the ionic liquid into the distillate. Preferred salts are Group IB salts, more preferably silver salts. A preferred silver salt is silver tetrafluoroborate. Preferred ionic liquids are those which form stable solutions or dispersions of the metal salts, and which do not dissolve the non-olefins. Further, if the olefins are subject to isomerization, the ionic liquid is preferably relatively non-acidic.

Abstract: The olefin-hydrogen effluent vapor stream from a dehydrogenation process is separated by a cryogenic separation method utilizing a cryogenic separation system. The method does not require external refrigeration and reheats and portions an expander feed stream to extract energy and controls the warm end and cold end temperature differences in the primary heat exchanger to provide energy savings and economical operation and material use.

Abstract: The method of producing high purity isooctane useful as a gasoline blending component from diisobutylene or isooctane contaminated with minor amounts of oxygenated impurities which comprises converting the impurities at conditions of elevated temperature and pressure to hydrocarbon and water and recovering the purified diisobutylene or isooctane stream.

Abstract: The invention relates to a new process for more efficient separation and recovery of light olefins such as ethylene and propylene from a fluid catalytic cracking unit. The new process invention for recovering olefins from a mixture of cracked hydrocarbons from a fluid catalytic cracker comprises the steps of: (a) providing a mixture of cracked hydrocarbons including methane, ethylene, ethane, propylene, propane, butylene, butane and heavier hydrocarbons such as naphtha produced in a fluid catalytic cracker; (b) separating said mixture into (i) a first stream comprising substantially all of said ethane, ethylene, and methane and a major portion of said propane and propylene and (ii) a second stream comprising a portion of said butylene and butane, and a major portion of said heavier hydrocarbons; and (c) processing said first stream to recover the ethylene and propylene therefrom, and the details of such process described herein.

Abstract: A process is provided for the concentration and recovery of ethylene and heavier components from an oxygenate conversion process. A separation process such as a pressure swing adsorption (PSA) process is used to remove hydrogen and methane from a demethanizer overhead stream comprising hydrogen, methane, and C2 hydrocarbons and subsequently return the recovered C2 hydrocarbons to be admixed with the effluent from the oxygenate conversion process. This integration of a separation zone with a fractionation scheme in an ethylene recovery scheme using an initial demethanizer zone resulted in significant capital and operating cost savings by the elimination of cryogenic ethylene-based refrigeration from the overall recovery scheme.

Abstract: A process for the isolation of high-boiling monomers from distillation residue formed in the cyclodimerization and/or cyclotrimerization of 1,3-butadiene after target products of cyclooctadiene, vinylcyclohexene and/or cyclododecatriene have been separated off, comprising extracting the distillation residue with a nonpolar or slightly polar solvent, separating off insoluble oligomers and polymers that have at least partly crystallized by mechanical separation, removing the extractant, and isolating the high-boiling monomers.

Abstract: The present invention provides an improved method for deep selective hydrogenation for use in recovering high purity olefins from cracked gas effluents or other paraffin/olefin gaseous mixtures by use of a chemical absorption process.

Abstract: An integrated debutanizer and low pressure depropanizer column and process for separating a feed stream comprising C3's, C4's and C5+ is disclosed. A single shell houses a refluxed upper portion and a lower portion of the column. A generally vertical wall partitions the lower portion of the column into a debutanizer section and a depropanizer stripper section. The upper column portion is used as the absorption section of the depropanizer. The feed is supplied to an intermediate stage in the debutanizer, and the debutanizer is operated at a lower pressure (and correspondingly lower temperature) matching that of the low pressure depropanizer. The design allows the use of one slightly larger column in place of the two large columns previously used for separate debutanization and low pressure depropanization.

Abstract: This invention relates to a process for separating and isolating saturated hydrocarbons from olefins, and in particular, to a process for separating and isolating saturated hydrocarbons from olefins in a Fisher-Tropsch stream.

Abstract: The invention relates to a new process for more efficient separation and recovery of light olefins such as ethylene and propylene from a fluid catalytic cracking unit. The new process invention for recovering olefins from a mixture of cracked hydrocarbons from a fluid catalytic cracker comprises the steps of: (a) providing a mixture of cracked hydrocarbons including methane, ethylene, ethane, propylene, propane, butylene, butane and heavier hydrocarbons such as naphtha produced in a fluid catalytic cracker; (b) separating said mixture into (i) a first stream comprising substantially all of said ethane, ethylene, and methane and a major portion of said propane and propylene and (ii) a second stream comprising a portion of said butylene and butane, and a major portion of said heavier hydrocarbons; and (c) processing said first stream to recover the ethylene and propylene therefrom, and the details of such process described herein.

Abstract: This invention relates to a process for separating and isolating saturated hydrocarbons from olefins, and in particular, to a process for separating and isolating saturated hydrocarbons from olefins in a Fisher-Tropsch stream, and thereafter treating the olefins to separate linear alpha olefins from internal olefins.

Abstract: A molecular sieve used in a process for separating olefinic hydrocarbons from paraffinic hydrocarbons is regenerated in a method which removes diolefins and aromatic hydrocarbons from the molecular sieve. The method comprises contacting the sieve with alkaline water and then drying the sieve with stream of a superheated light paraffin. The molecular sieve may be present in either a guard bed used upstream of a main separation zone or as part of the main adsorptive separation zone.

Abstract: The invention provides specific adsorbents and methods for separating an unsaturated hydrocarbon from a mixture containing such hydrocarbon. The adsorbents and methods are useful for separating dienes from mono-olefins.

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: This invention relates to a process for separating functionalized alpha olefins from functionalized internal olefins. The process achieves by a step of contacting a feedstock containing functionalized alpha olefins and functionalized internal olefins with a linear polyaromatic compound to form a linear polyaromatic compound-functionalized alpha olefin adduct and a step of dissociating the linear polyaromatic compound-functionalized alpha olefin adduct to form linear polyaromatic compounds and a functionalized alpha olefin composition.

Abstract: Processes using heterogeneous adsorbents are disclosed for purification of relatively impure unsaturated hydrocarbons such as olefins, which are typically produced by thermal cracking of suitable hydrocarbon feedstocks, by passing a feed stream, containing acetylenic impurities, and, optionally, saturated hydrocarbon gases, through a particulate bed predominantly comprising a support material having high a surface area on which is dispersed at least one metallic element. Adsorption is carried out in an essentially dihydrogen-free atmosphere within the bed, effecting selective and reversible adsorption and/or complexing of the contained acetylenic contaminants with the adsorbent, thereby obtaining purified effluent which contains less than a predetermined level of the acetylenic impurities. Selective and reversible adsorption and/or complexing of the contained acetylenic impurities with the adsorbent is continued until levels of acetylenic impurities in the effluent stream increase to a predetermined level.

Abstract: A molecular sieve guard bed used in an adsorptive process for separating olefinic hydrocarbons from paraffinic hydrocarbons is regenerated in a method which recovers valuable hydrocarbons from the guard bed void volumes. The method comprises first contacting the sieve with a purge stream, with the initial effluent of the guard bed passed into a raffinate column to recover the olefinic hydrocarbons in the void volume of the bed. The flow of the effluent of the guard bed is then switched to a different fractionation column.

Abstract: Process flow sequences for the reduction of equipment fouling in the fractional distillation of light end hydrocarbon components, such as those produced by pyrolysis or steam cracking, wherein conventional multiple hydrogenation unit configurations are replaced with upstream hydrogenation unit configurations. The upstream hydrogenation units of the invention are located at either side draws or in the reboiler circuit of deethanizers, in front-end demethanizer and front-end deethanizer sequences, or depropanizers, in front-end depropanizer sequences and obviate the need for most of the conventionally used hydrogenation units downstream.

Abstract: Process technology is described making possible substantial improvements in the separation and recovery of highly pure vinyl aromatic monomers, notably styrene. A number of design, construction and operational features are made available for selection and use both for new plant facilities and for upgrading existing plant facilities. One major aspect of the invention is reduction in retention or residence times in the distillation towers. In another embodiment, a startup process comprises (i) introducing a feed comprising vinylaromatic monomer, polymerization inhibitor, aromatic hydrocarbon components having boiling points above that of the vinylaromatic monomer to a packed distillation column, said column having a maximum theoretical .DELTA.

Abstract: Processes using heterogeneous adsorbents are disclosed for purification of olefins such as are typically produced by thermal cracking of suitable hydrocarbon feedstocks, by passing a stream of olefin having from 2 to about 8 carbon atoms, containing acetylenic impurities having the same or similar carbon content, and optionally saturated hydrocarbon gases, through a particulate bed of predominantly a support material having high surface area on which is dispersed at least one metallic element. Adsorption is carried out in an essentially dihydrogen-free atmosphere within the bed, selective and reversible adsorption and/or complexing of the contained acetylenic contaminants with the adsorbent, and thereby obtain purified effluent which contains less than a predetermined level of the acetylenic impurities.

Abstract: A process for the separation and removal, of hydrogen, alone or together with carbon monoxide, if present, from a mixture of these gases with reactive unsaturated hydrocarbons, by contacting the mixture with oxygen over a catalyst at conditions sufficient to oxidize the hydrogen to form water while suppressing reaction of the reactive, unsaturated hydrocarbons. The catalyst contains at least one metal or metal oxide from Groups IB, IIB, IIIB, IVB, VB, VIB, VIIB, and VIII of the Periodic Table, and the temperature of the reaction may range from about 40.degree. C. to about 300.degree. C., the pressure of the reaction ranges from about 14.7 psig to 1,000 psig, and the flow rate of the entering feed ranges from about 1 GHSV to about 50,000 GHSV. Oxygen amounts less than the stoichiometric amount required to react with the hydrogen, and optionally any carbon monoxide, are used.

Abstract: A process for the separation of propylene from an input stream of C3 hydrocarbons containing propylene and methyl acetylene and/or propadiene and, optionally, C4 and/or higher hydrocarbons is described. The process includes subjecting the input stream to fractional distillation to separate propylene as an overhead stream leaving a bottoms stream containing the methyl acetylene and/or propadiene and the C4 and/or higher hydrocarbons, when present. A propane-containing stream is added to said input stream whereby propane is separated as part of the bottoms stream. The propylene content of the bottoms streams is maintained at less than 10% weight. The amount of propane added to the input stream is such that the weight of propane, propylene, and C4 and/or higher hydrocarbons, when present, in the bottoms stream is greater that the total weight of methyl acetylene and propadiene in the bottoms stream.

Abstract: A process and apparatus are provided for recovering diluent, unreacted monomer, and unreacted comonomer from a polymerization reactor effluent. The comonomer has a boiling point higher than the boiling point of the monomer and the diluent has a boiling point between the boiling points of the monomer and comonomer. The process and apparatus employ at least one flash tank, a first fractionation stage including a first column and operating at a first fractionation pressure, and a second fraction stage including a second column and operating at a higher second fractionation pressure. Comonomer is withdrawn from the first column as a fractionation product, and overhead vapor containing diluent and monomer is substantially condensed to yield a substantially condensed overhead stream. Liquid and vapor from the stream are separated in an accumulator.

Abstract: A feedstock of linear internal olefins and branched internal olefins are converted to a primarily linear internal olefin composition having a lower concentration of branched internal olefins than present in the feedstock, by:a) contracting the feedstock with linear polyaromatic compound under conditions effective to form a reaction mixture comprising an linear polyaromatic compound-linear internal olefin adduct;b) separating the linear polyaromatic compound-linear internal olefin adduct from the reaction mixture;c) dissociating the linear polyaromatic compound-linear internal olefin adduct to form linear polyaromatic compound and a linear internal olefin composition, andd) separating the linear polyaromatic compound formed in step c) from a linear internal olefin composition.