Abstract: A low-pressure olefins recovery process and plant are described. The feed gas is compressed and distilled at a primary distillation pressure. The overhead stream is chilled at a pressure less than 30 kg/cm2 (430 psia) to partially condense the overheads. The primary distillation tower is refluxed with at least a portion of the condensate. The overhead vapor is further chilled and partially condensed and the condensate is fed to a demethanizer. The remaining vapor is cooled in a cold section and the resultant liquid is phase-separated and expanded to provide refrigeration for the cold section. The expanded vapor from the cold section is recycled to the process gas compressor. The bottoms streams from the primary distillation zone and the demethanizer are fractionated into respective streams consisting essentially of ethylene, ethane, propylene, propane, C4's, and C5+.

Abstract: This invention relates to a process for the oligomerization of olefins that have 2 to 6 carbon atoms comprising at least: a) One reaction stage in which a first effluent that comprises oligomers, paraffins and olefins that have not reacted is recovered, b) A separation stage that makes it possible to separate a portion of the oligomers that are contained in the effluent from a mixture that comprises oligomers, paraffins and the olefins that have not reacted, c) A recycling of a portion of said mixture in the reaction stage, and d) A stage for membrane separation of another portion of said mixture so as to draw off a permeate that comprises at least 70% by weight of olefins and a retentate that comprises paraffins and oligomers, e) A stage for recovery of oligomers on the retentate.

Abstract: A process for the oxidation of a C2 to C4 alkane to produce the corresponding alkene and carboxylic acid which process comprises separation of the alkene from a mixture of the alkene, the alkane and oxygen by absorption in a metallic salt solution, and recovery of an alkene-rich stream from the metallic salt solution. Integrated processes for the production of alkyl carboxylate and alkenyl carboxylate, which processes comprise oxidation of a C2 to C4 alkane to produce the corresponding alkene and carboxylic acid, separation of the alkene from a mixture of the alkene, the alkane and oxygen by absorption in a metallic salt solution, and recovery of an alkene-rich stream from the metallic salt solution for use in production of alkyl carboxylate or alkenyl carboxylate.

Abstract: The present invention provides a process for removing methyl acetylene and/or propadiene from a propylene stream and/or a butylene stream by two step fractionation. Methyl acetylene and/or propadiene avoids the use of a hydrogenation reactor and makes the methyl acetylene and/or propadiene recoverable from the process.

Abstract: A process for the separation or concentration of olefinic hydrocarbons from mixtures of olefinic and paraffinic hydrocarbons uses a polyimide membrane, The process is well suited to separating propylene from propylene/propane mixtures. The novel method the membrane exhibits good resistance to plasticization by hydrocarbon components in the gas mixture under practical industrial process conditions.

Abstract: Sudstituted the abstract with a new abstract as follows: The invention relates to a continuous process for separation a mixture of hydrocarbons which has beenobtained by extractive distillation of C4 fraction useing a selective solvent and the hydrocarbons from the fraction C4 which are more readily soluble in the selective solvent than are the butanes and the butenes. The mixture is fed into a first distillation column in which it is separated into a steam which is taken off at the top and comprises 1,3-butadiene, propyne, possibly further low boilers and possibly water and a bottom stream comprising 1,3-butadiene, 1,2-butadiene, acetylenes and possibly further high boilers, with the proportion of 1,3-butadiene in the bottom stream from the distillatin column being regulated in such a way that it is at least sufficiently high to dilute the acetylenes to outside the range in which there is a risk of spontaneous decomposition.

Abstract: The process of the invention comprises contacting a hydrocarbon stream, comprising light olefins plus impurities such as acetylenes, in the absence of hydrogen with a supported copper catalyst, preferably CuO/alumina. The acetylene component undergoes a coupling reaction producing a diacetylene which can be more readily removed. Thus, the methylacetylene (MA) contaminant in liquid propylene yields at about 80° C. and 3792 kPa (550 psig) a significant amount dimethyl diacetylene (2,4-hexadiyne). Surprisingly, very little cyclization products are present. The process is useful for purification of olefin feeds. It can be used alone or in combination with known purification methods such as catalytic distillation or selective hydrogenation.

Abstract: The present invention relates to dewaxing aids comprising the mixture of two or more polyalkyl(meth)acrylates having an exothermic heat initiation temperature within the specific range when chilled at 30° C./minute rate, to be added together with the wax-containing hydrocarbon oil to the dewaxing solvent. The dewaxing aid according to the present invention can be used in the solvent dewaxing method containing the stage in which the chilling rate during the chilling is 30° C./minute or higher, is effective for heavy type wax-containing hydrocarbon oils, and is chlorine-free.

Abstract: The present invention provides processes for removing CO2 from an effluent stream derived from an oxygenate to olefins reaction system. In one embodiment, the invention comprises contacting the effluent stream with a first CO2 removal medium in a first CO2 removal zone under conditions effective to remove a first portion of the CO2 from the effluent stream and form a first CO2 depleted stream. The first CO2 depleted stream is contacted with a second CO2 removal medium in a second CO2 removal zone under conditions effective to remove a second portion of the CO2 from the first CO2 depleted stream and form a second CO2 depleted stream comprising less than about 0.5 vppm CO2.

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 process is described for producing olefins from a vapor product stream from an oxygenate to olefin conversion reaction, the vapor product stream comprising C2 to C4 olefins, C5+ hydrocarbons, at least one oxygenate and water. In the process, the vapor product stream is cooled to remove water therefrom and produce a first vapor effluent stream. The first vapor effluent stream is then cooled and compressed to produce a condensed liquid effluent stream comprising C5+ hydrocarbons and at least one oxygenate, and a residual vapor effluent stream comprising C2 to C4 olefins. At least part of the condensed liquid effluent stream is contacted with a liquid water-containing stream in a liquid-liquid contacting device to at least partly separate said condensed liquid effluent stream, or portion thereof, into an aqueous phase rich in said at least one oxygenate and an organic phase rich in said C5+ hydrocarbons.

Abstract: An integrated process for the isolation of benzene contained within a fluid catalytically cracked naphtha is disclosed wherein a C6 fraction containing a benzene concentrate is subjected to etherification with alcohol (e.g. methanol and/or ethanol) to convert the C6 isoolefins to ethers which are separated by fractional distillation. If desired the ethers may be dissociated to the isoolefins and alcohol. The remaining material in the benzene concentrate may then be treated to remove olefins and organic sulfur compounds so that the benzene may be removed by solvent extraction. Alternatively the benzene in the remaining material may be subjected to hydrogenation.

Abstract: This invention covers a process for making Octene from mix C4 Feed by a low cost highly selective multistage process. The multi staging of reactors essentially provides lower cost than conventional processes. Two options are provided in FIGS. 1 and 2 as regards to configuration based on the same catalyst but as can be seen that FIG. 1 configuration is low cost option with very high selectivity. The process provides conversion of butene to Octene >95% and product purity >96%. Product can be fractionated and can have a high purity Octene product by removing the trimers/polymers from the octene product. As mentioned due to the nature of the process configuration, one achieves high yield and selectivity with low cost.

Abstract: In a method for the solvent extraction of butadiene from a mixture of hydrocarbons having four carbon atoms per molecule, which method inherently produces tars, the extraction process is operated with a tar loading level, relative to the solvent employed, of no more than about 1.6 wt. %.

Abstract: A process is described for producing an olefins stream from a first vapor effluent stream from an oxygenate to olefin conversion reaction, said first vapor effluent stream comprising C2 and C3 olefins, C4 hydrocarbons, and C2 to C6 carbonyl compounds. In the process, the temperature and pressure of the first vapor effluent stream are adjusted to produce a second vapor effluent stream having a pressure ranging from about 100 psig to about 350 psig (790 to 2514 kPa) and a temperature ranging from about 70° F. to about 120° F. (21 to 49° C.), said second vapor effluent stream containing about 50 wt. % or more C4 hydrocarbons based upon the total weight of C4 hydrocarbons in the first vapor effluent stream. The second vapor effluent stream is then washed with a liquid alcohol-containing stream to produce a third vapor effluent stream, whereafter the third vapor effluent stream is washed with liquid water to provide a fourth vapor effluent stream comprising the C2 and C3 olefins and about 1.0 wt.

Abstract: The economics of a catalytic process using a fluidized conversion zone and a relatively expensive catalyst for converting an oxygenate to light olefins are substantially improved by recovering and recycling effluent contaminating catalyst particles from the product effluent stream withdrawn from the conversion zone which are present despite the use of one or more vapor-solid cyclone separating means to clean up this effluent stream. The contaminating catalyst particles are separated from this product effluent stream using a wet scrubbing zone and an optional dewatering zone to recover a slurry containing the contaminated particles which, quite surprisingly, can be successfully directly recycled to the oxygenate conversion zone or to the associated catalyst regeneration zone without loss of any substantial amount of catalytic activity thereby decreasing the amount of fresh catalyst addition required to make up for this source of catalyst loss.

Abstract: Removing impurities from a heptane stream by contacting the heptane stream with an acidic catalyst, wherein the contacting reduces a concentration of one or more close boiling impurities, one or more olefins, or both. The impurities are isomerized via contact with the acidic catalyst into species that possess lower octane levels or that do not possess boiling points as near to the boiling point of n-heptane, which promotes separation of the impurities via distillation. Close boiling impurities may include such compounds as cis-1,2-dimethylcyclopentane and methylcyclohexane or may be compounds having boiling points at a standard pressure of 760 Torr in the range of about 96.5 to about 100.5 degrees Celsius including such compounds as cis-1,2-dimethylcyclopentane and methylcyclohexane. The concentration of cis-1,2-dimethylcyclopentane and methylcyclohexane may be reduced by at least about 25 and 10 percent by weight, respectively.

Abstract: This invention is to a process for removing dimethyl ether from an olefin stream. The process includes contacting the olefin stream with a molecular sieve that has improved capacity to adsorb the dimethyl ether from the olefin stream. The molecular sieve used to remove the dimethyl ether has low or no activity in converting the olefin in the olefin stream to other products.

Abstract: This invention is directed to a process for condensing and removing condensable compounds from an olefin stream containing light olefin compounds, and recovering the light olefin compounds. The process of the invention is particularly effective in removing water and heavy hydrocarbons, particularly aromatic hydrocarbons, from an olefin stream made from the catalytic conversion of oxygenate, and recovering light olefins such as ethylene, propylene, butylene, or a mixture thereof.

Abstract: Catalysts for the purification of ethylene containing copper and zinc, optionally one or more promoters or supports. These catalysts are produced by precipitation, drying, calcination and compression, optionally with the addition of additives, the compressed catalyst particles are calcinated at a temperature between from 300 to 700° C.

Abstract: This invention is an improved distillation sequence for the separation and purification of ethylene from a cracked gas. A hydrocarbon feed enters a C2 distributor column. The top of the C2 distributor column is thermally coupled to an ethylene distributor column, and the bottoms liquid of a C2 distributor column feeds a deethanizer column. The C2 distributor column utilizes a conventional reboiler. The top of the ethylene distributor is thermally coupled with a demethanizer column, and the bottoms liquid of the ethylene distributor feeds a C2 splitter column. The ethylene distributor column utilizes a conventional reboiler. The deethanizer and C2 splitter columns are also thermally coupled and operated at a substantially lower pressure than the C2 distributor column, the ethylene distributor column, and the demethanizer column. Alternatively, a hydrocarbon feed enters a deethanizer column.

Abstract: The present invention relates to a process for the liquid-liquid extraction or liquid-gas extraction of mixtures of organic compounds, in which one or more components of the mixture are completely or partly extracted by means of a phase comprising at least one ionic liquid.

Abstract: A low-pressure olefins recovery process and plant are described. The feed gas 300 is compressed 302, 304 and distilled 310 at a primary distillation pressure. The overhead stream 312 is chilled 318 at a pressure less than 30 kg/cm2 (430 psia) to partially condense the overheads. The primary distillation tower 310 is refluxed with at least a portion of the condensate 320. The overhead vapor is further chilled 318 and partially condensed and the condensate 322 is fed to a demethanizer 324. The remaining vapor 326 is cooled in a cold section 328 and the resultant liquid is phase-separated 330 and expanded 331, 334 to provide refrigeration for the cold section. The expanded vapor 332 from the cold section is recycled to the process gas compressor. The bottoms streams 338, 342 from the primary distillation zone and the demethanizer are fractionated into respective streams consisting essentially of ethylene 356, ethane 358, propylene 364, propane 366, C4's 346, and C5+ 348.

Abstract: A process is described for producing olefins from a vapor product stream from an oxygenate to olefin conversion reaction, the vapor product stream comprising C2 to C4 olefins, C5+ hydrocarbons, at least one oxygenate and water. In the process, the vapor product stream is cooled to remove water therefrom and produce a first vapor effluent stream. The first vapor effluent stream is then cooled and compressed to produce a condensed liquid effluent stream comprising C5+ hydrocarbons and at least one oxygenate, and a residual vapor effluent stream comprising C2 to C4 olefins. At least part of the condensed liquid effluent stream is contacted with a liquid water-containing stream in a liquid-liquid contacting device to at least partly separate said condensed liquid effluent stream, or portion thereof, into an aqueous phase rich in said at least one oxygenate and an organic phase rich in said C5+ hydrocarbons.

Abstract: The present invention is a process for quenching a reactor effluent stream. The reactor effluent stream comprises water, olefin product, and methanol and is further entrained with catalyst fines. The process removes water, catalyst fines, and methanol. Particularly, methanol removal from the reactor effluent stream is improved.

Abstract: A process for the recovery of high purity hydrogen for recycling to a hydroprocessing or similar unit located in an integrated refinery facility includes sampling and providing analytical information on the make-up of the hydrogen-containing feedstream entering the bottom of a stripping column and the composition of the hydrogen recycle stream at, and/or approaching the top of the stripping column to a computer-directed control system in real time for the purpose of controlling the selection and the volumetric flow rate of one or more “refinery solvents” into the column to maximize the removal of non-hydrogen gases from the feedstream and to thereby maximize the percentage of hydrogen in the recycle gas stream.

Abstract: A process for the separation or concentration of olefinic hydrocarbons from mixtures of olefinic and paraffinic hydrocarbons uses a polyimide membrane. The process is well suited to separating propylene from propylene/propane mixtures. The novel method The membrane exhibits good resistance to plasticization by hydrocarbon components in the gas mixture under practical industrial process conditions.

Abstract: It has now been disclosed that by directing the effluent from an oligomerization reactor to a water wash column to remove alcohol modifier from the hydrocarbon stream before sending it to a fractionation column offers flexibility in providing a bottoms product of a desired vapor pressure without increasing the concentration of alcohol modifier in the overhead stream beyond alcohol concentration limits.

Abstract: A method for processing an olefin-containing product stream that contains dimethyl ether as a by-product is described. Such a product stream arises, for example, in the synthesis of olefin from methanol. For separation of the dimethyl ether from the product stream, it is proposed that at least a partial stream chiefly containing C3 hydrocarbons is separated from the product stream by fractionation, and is sent to a rectification column (C3 splitter) (16) for separation of propylene and propane. The dimethyl ether goes together with the propane into the bottom of the rectification column in the rectification process and can be withdrawn (42). A substantially pure propylene product (41), which contains at most only traces of dimethyl ether, can be removed from the top of the rectification column.

Abstract: In a process for reducing the Bromine Index of a feed containing a linear alkylbenzene and bromine-reactive olefinic hydrocarbon contaminants, the feed is contacted under conditions effective to remove bromine-reactive olefinic hydrocarbon contaminants with a catalyst comprising zeolite Y catalyst having an alpha value of about 2 to about 30. The feed will normally also contain benzene and linear paraffin remaining from the alkylation process used to produce the linear alkylbenzene.

Abstract: The present invention provides new highly-efficient separation processes and systems for separating polymerization-grade ethylene and propylene from an initial effluent stream comprising ethane, ethylene, propylene, dimethyl ether, and one or more of propane, acetylene, methyl acetylene, propadiene, methane, hydrogen, carbon monoxide, carbon dioxide and C4+ components. In one embodiment, the initial effluent stream is provided from a methanol-to-olefin reaction system. It has been discovered that an efficient separation of these components is realized when DME is partially removed in a first separation step comprising methanol and water washing steps, followed by separation of the remaining components in additional separation steps.

Abstract: The present invention is directed toward reducing corrosion in a methanol-to-olefin (MTO) effluent processing system, and particularly in the condensate removal system thereof, by injecting a neutralization agent into one or more target regions of the MTO effluent processing system. The neutralization agent ensures that any localized condensation in the MTO effluent processing system, particularly in the condensate removal system, occurs under basic conditions and that any acidic condensable components are neutralized. The invention is also directed to monitoring corrosion in an MTO effluent processing system and to monitoring the pH of localized corrosion sites in order to ensure proper neutralization of any acidic condensation formed therein.

Abstract: The present invention provides new highly-efficient separation processes and systems for separating polymerization-grade ethylene and propylene from an initial effluent stream comprising ethane, ethylene, propylene, dimethyl ether, and one or more of propane, acetylene, methyl acetylene, propadiene, methane, hydrogen, carbon monoxide, carbon dioxide and C4+ components. In one embodiment, the initial effluent stream is provided from a methanol-to-olefin reaction system. It has been discovered that an efficient separation of these components is realized when DME is partially removed in a first separation step comprising methanol and water washing steps, followed by separation of the remaining components in additional separation steps.

Abstract: An improved methanol-to-olefin (MTO) product recovery scheme is provided which enables substantial reduction in the amount of light olefins that are undesirably captured in a dimethylether (DME) recycle stream when a portion of the methanolic feed to the MTO reaction zone is used as the scrubbing solvent in a primary DME absorption zone in order to recycle this DME oxygenate by-product to the MTO reaction zone. In accordance with the present invention, a liquid solvent stream recovered from the primary DME absorption zone is subjected in a stripping zone to light olefin stripping conditions sufficient to lift a substantial portion of the light olefins that are absorbed in the DME solvent without stripping a significant portion of this methanol solvent, thereby increasing the recovery of desired light olefins while simultaneously diminishing the amount of light olefins carried by the DME recycle stream back to MTO conversion step.

Abstract: The present invention is a process for removal of carbon dioxide from a reactor effluent stream comprising water, carbon dioxide and olefin(s), where a portion of the carbon dioxide is removed in a quenching step with a quench medium and more carbon dioxide is removed by contacting the quenched effluent stream with an alkaline stream. A portion of the alkaline stream is added to the quench medium.

Abstract: An improved methanol-to-olefin (MTO) product recovery scheme is provided which enables substantial reduction in the amount of light olefins that are undesirably captured in a dimethylether (DME) recycle stream and improved recovery of methanol when a portion of the methanolic feed to the MTO reaction zone is used as the scrubbing solvent in a primary DME absorption zone in order to recycle this DME oxygenate by-product to the MTO reaction zone. In accordance with the present invention, a liquid solvent stream recovered from the primary DME absorption zone is subjected in a stripping zone to light olefin stripping conditions sufficient to lift a substantial portion of the light olefins that are absorbed in the DME solvent without stripping a significant portion of this methanol solvent, thereby increasing the recovery of desired light olefins while simultaneously diminishing the amount of light olefins carried by the DME recycle stream back to MTO conversion step.

Abstract: An apparatus for recovering ethylene from a hydrocarbon feed stream, where the apparatus is a single distillation column pressure shell encasing an upper region and a lower region. The upper region houses an ethylene distributor rectifying section and the lower region houses a C2 distributor section and an ethylene distributor stripping section. Vapor passes from the lower region into the upper region, and liquid passes from the upper region to the lower region. The process for recovering the ethylene is also disclosed. The hydrocarbon feed stream is introduced into the C2 distributor section, and after a series of stripping and refluxing steps, distinct hydrocarbon products are recovered from the C2 distributor section, the ethylene distributor stripping section, and the ethylene distributor rectifying section, respectively.

Abstract: A catalyst system and process for combined cracking and selective hydrogen combustion of hydrocarbons are disclosed. The catalyst comprises (1) at least one solid acid component, (2) at least one metal-based component comprised of two or more elements from Groups 4–15 of the Periodic Table of the Elements and at least one of oxygen and sulfur, wherein the elements from Groups 4–15 and the at least one of oxygen and sulfur are chemically bound both within and between the groups and (3) at least one of at least one support, at least one filler and at least one binder. The process is such that the yield of hydrogen is less than the yield of hydrogen when contacting the hydrocarbons with the solid acid component alone.

Abstract: The present invention is a process for removing catalyst fines from an effluent stream in an oxygenate to olefin process. Specifically, the catalyst fines in the effluent stream are separated from the effluent stream. Then the carbonaceous deposits are removed from the catalyst fines by incineration.

Abstract: The present invention is a process for producing olefin(s) from oxygenates that is more effective than previously known processes at removing carbon dioxide from the effluent stream by operating a quench tower at a pH greater than 7.0.

Abstract: Disclosed are compositions comprising C26H30 hexamantane, referred to herein as peri-condensed hexamantane, fully condensed hexamantane, and cyclohexamantane. These enriched cyclohexamantane compositions comprise at least 5 percent by weight cyclohexamantane based upon the total weight of the composition.

Abstract: Process for recovery of hydrogen in an effluent that is rich in hydrocarbons and that also contains hydrogen and a light olefin fraction, whereby said process comprises: a stage a) in which said effluent is brought into contact with at least one reagent that can react with said olefins to form with them a complex or a molecule; a stage c) in which the effluent that is obtained from stage a) is brought into contact with a composition that comprises at least one unsaturated compound in the presence of a suitable catalyst under hydrogenation conditions of at least a portion of said unsaturated compound by at least a portion of the hydrogen that is present in said effluent; a stage d) in which a reaction for dehydrogenation of hydrocarbons that are present in the effluent that is obtained from stage c) is carried out.

Abstract: The present invention provides new highly-efficient separation processes and systems for separating polymerization-grade ethylene and propylene from an initial effluent stream comprising ethane, ethylene, propylene, dimethyl ether, and one or more of propane, acetylene, methyl acetylene, propadiene, methane, hydrogen, carbon monoxide, carbon dioxide and C4+ components. In one embodiment, the initial effluent stream is provided from a methanol-to-olefin reaction system. It has been discovered that the best separation of these components is realized when DME is selectively removed in a first separation step, followed by separation of the remaining components in additional separation steps.

Abstract: Disclosed is a method of removing dimethyl ether from an ethylene and/or propylene containing stream. Dimethyl ether is removed at a high pressure, preferably in a distillation column. The high pressure separation has the benefit of providing a relatively low bottoms temperature separation, while allowing for recovery of a highly concentrated ethylene and/or propylene stream.

Abstract: Disclosed is a process for removing DME from a stream containing C4 olefins. The process includes providing a first stream comprising C4 olefins, C5+ hydrocarbons, DME, and methanol. The first stream is separated into a second stream comprising the C4 olefins and the DME and a third stream comprising the C5+ hydrocarbons and the methanol. The second stream is directed to a DME absorption unit, wherein the second stream contacts water under conditions effective to separate the C4 olefins from the DME. Also disclosed is a process including contacting the first stream with water in a methanol removal unit under conditions effective to separate remove the methanol therefrom; distilling the methanol-depleted stream to remove C5+ hydrocarbon components, and contacting the stream with water in a DME removal unit under conditions effective to form an overhead stream comprising the C4 olefins and a bottoms stream comprising the DME.

Abstract: The charge gas from the thermal cracking of a hydrocarbon feedstock is processed in a front-end catalytic distillation hydrogenation system of an olefins plant to more effectively recover ethylene and propylene product and to process the by-products. The rate of fouling in the system is reduced by employing two columns in the system with the first column operating at a higher pressure and the second column operating at a lower pressure. The hydrogenation as well as fractionation takes place in the first column while the second column is only a fractionator. The temperature of the bottoms from each column is maintained at a temperature less than 200° C. to avoid fouling.

Abstract: A method is disclosed a method for recovering olefins and for producing hydrogen from a refinery off-gas stream in which such stream is conventionally pretreated and separated to obtain a light ends stream that contains nitrogen, hydrogen and carbon monoxide and a heavy ends stream that contains the olefins. The light ends stream is subjected to reforming and a water gas shift reactions after addition of a natural gas stream. The addition of the natural gas increases the hydrogen recovery from the light ends and also stabilizes the hydrocarbon content in the stream to be subjected to the reforming and water gas shift reactions. The heavy ends can be further treated to recover olefins such as ethylene and propylene. The rate of natural gas addition is controlled so that the concentration of the nitrogen in a stream exiting the water gas shift reactor is less than about 5 percent by volume so that hydrogen separation from such stream becomes practical.

Abstract: A method for operating a dimerization reactor that receives a hydrocarbon feed and produces an output stream comprising a light hydrocarbon component, a dimer and an alcohol component comprises: (a) separating the first output stream into a top stream containing the light hydrocarbon and a bottom stream containing the dimer, with the alcohol being present in the top stream or the bottom stream or both; (b) contacting at least one of the bottom and top streams with a water stream so as to extract at least a major portion of the alcohol therefrom, thereby forming an water/alcohol stream; (c) contacting the water/alcohol stream with a hydrocarbon stream so as to extract at least a major portion of the alcohol present in the water/alcohol stream into the hydrocarbon stream, thereby forming an alcohol-enriched hydrocarbon stream; and (d) feeding the alcohol-enriched hydrocarbon stream into the dimerization reactor.

Abstract: A process is provided for converting oxygenate to olefins from a fluidized bed reactor which comprises removal of catalyst fines from a quenched vaporous effluent by contacting with a liquid low in catalyst fines content, e.g., oxygenate feedstock, or by-product water from the oxygenates to olefins conversion which is stripped and/or filtered.

Abstract: Process for obtaining a hydrocarbon fraction that can be used as a feedstock of an etherification unit and that contains a small amount of diene compounds, nitrogen-containing compounds and sulfur-containing compounds, starting from an initial hydrocarbon feedstock that comprises a mixture of olefins, dienes, and nitrites as well as sulfur-containing compounds, whereby said process comprises at least the following successive stages: a) a selective hydrogenation of said initial hydrocarbon feedstock in the presence of a catalyst of group VIII of the periodic table, b) a fractionation by distillation of the effluents that are obtained from stage a) under conditions that make it possible to obtain at least two fractions including said hydrocarbon fraction and that comprises a small amount of diene compounds, nitrogen-containing compounds and sulfur-containing compounds, and a heavy fraction that contains heavy hydrocarbons and the majority of the nitrogen-containing compounds and sulfur-containing compounds