Abstract: A nanocomposite composition for oxidative desulfurization of liquid hydrocarbon fuels, is disclosed. The nanocomposite composition comprises an amorphous mesoporous titania-silica (TiO2—SiO2) nanocomposite oxidative desulfurization (ODS) catalyst-adsorbent, including, a chelating agent, an alcohol, an alkoxides precursor of silica and titania, water, an organic polymer and a textural agent. The nanocomposite ODS catalyst-adsorbent is prepared with the aid of polyethylene glycol (PEG) as directing agent and citric acid (CA) as chelating agent. The PEG increases the specific surface area and average pore diameter of ODS catalyst-adsorbent, which facilitates the diffusion of bulky sulfur compounds into porosities of catalyst and adsorption of oxidized sulfur compounds on the catalyst surface. The citric acid controls the hydrolysis and condensation of titanium precursor, which improves ODS performance of catalyst-adsorbent.

Abstract: Improvements in the commercial viability of oxygen transfer agents (OTAs) and/or catalysts associated with the OCM and the ODH of hydrocarbons to olefins through enhancement of one or more of the selectivity, yield, rate and lifetime of the OTA and/or catalyst is described by one or more of (i) exposing the OTA or the catalyst to a sulfur-containing compound at a site or at a time that is different from where and when the saturated hydrocarbon is converted by the OTA or the catalyst to an unsaturated hydrocarbon; (ii) increasing the particle density of the OTA or the catalyst by treating the OTA or the catalyst with a reducing agent at a site different from where the saturated hydrocarbon is converted by the OTA or by the catalyst to an unsaturated hydrocarbon; and (iii) removing non-selective redox oxygen (NSRO) present on the OTA by subjecting the OTA to a gas that is substantially free of any molecular oxygen.

Abstract: The present disclosure provides systems and methods for producing olefins via an oxidative coupling of methane (OCM) process. The systems and methods may comprise the use of a staged process comprising at least one non-adiabatic section that is in thermal communication with a heat transfer medium and at least one substantially adiabatic section. The systems and methods may also comprise the use of a diluent stream which may improve methane conversion in an OCM reactor and an ethylene/ethane ratio in a post-bed cracking unit. The methods and systems may further comprise injecting oxygen (O2) and a paraffin into a gas stream containing a radical transfer agent to provide a reaction mixture. The reaction mixture may be held in a vessel for a time period greater than an auto-ignition delay time (AIDT), such that the reaction mixture may ignite to liberate heat and convert to a product mixture comprising olefins.

Abstract: The invention relates to a process for the steam cracking of a feedstock composed of at least 80% by weight, in particular of at least 90% by weight, of ethane, the process comprising a steam cracking of the feedstock in a furnace (2), then a quenching of the pyrolysis products, then a compression operation, then a series of successive operations on the products resulting from the quenching, the said series of operations comprising a washing operation, followed by a drying operation and at least one compression operation, and finally a fractionation by cryogenic distillation. A selective hydrogenation operation, followed by a catalytic conversion operation, will be inserted into the said process, after the drying operation and before the fractionation, in order to partially convert the ethylene predominantly into propylene.

Abstract: The present invention describes a process for the conversion of a heavy feed which can be used to improve the selectivity for middle distillate. The process employs a catalytic cracking unit followed by one or more units for the oligomerization of C2 to C9 olefins which can preferentially produce an additional cut termed the middle distillate. The light portion of the oligomerate produced which cannot be incorporated into the middle distillate cut is recycled to the FCC unit for cracking into light olefins which are returned to the oligomerization units as a supplement to the olefins of the feed in order to preferentially form heavy oligomerates which can be incorporated into the middle distillate cut.

Abstract: Disclosed herein are processes for dehydrogenation of an alkane to an alkene using an iridium pincer complex and iridium pincer complexes. In the dehydrogenation reactions, hydrogen that is co-formed during the process must be removed for the chemical reaction to proceed and to prevent the excess hydrogen from poisoning the catalyst. In one embodiment the process comprises providing an alkane feedstock comprising at least one alkane and contacting the alkane with an iridium pincer complex in the presence of a hydrogen acceptor selected from the group consisting of ethylene, propene, or mixtures to form an alkene product. The processes disclosed herein can accomplish facile, low-temperature transfer dehydrogenation of alkanes with unprecedented selectivities and TONs at a reasonable rate of conversion.

Abstract: A process for increasing the yields of light olefins and the yields of aromatics from a hydrocarbon stream is presented. The process includes a first separation to direct the light components that are not reformable to a cracking unit, with the remainder passed to a second separation unit. The second separation unit extracts normal components from the hydrocarbon stream to pass to the cracking unit. The resulting hydrocarbon stream with reduced light ends and reduced normals is passed to a reforming unit.

Abstract: A process for increasing the yields of light olefins and the yields of aromatics from a hydrocarbon stream is presented. The process includes a first separation to direct the light components that are not reformable to a cracking unit, with the remainder passed to a second separation unit. The second separation unit extracts normal components from the hydrocarbon stream to pass to the cracking unit. The resulting hydrocarbon stream with reduced light ends and reduced normals is passed to a reforming unit.

Abstract: A process for producing olefins from a coal feed includes providing a coal tar stream and fractionating the coal tar stream to provide a hydrocarbon stream that includes hydrocarbons having an initial boiling point of about 250° C. or greater. The hydrocarbon stream is hydrotreated to reduce a concentration of one or more of nitrogen, sulfur, and oxygen in the hydrocarbon stream, and the hydrotreated hydrocarbon stream is cracked in a fluidized catalytic cracking zone to produce an olefin stream.

Abstract: The present invention relates to a process to make alpha olefins comprising: dehydrating ethanol to recover an ethylene stream, introducing said ethylene stream into an oligomerization zone containing an oligomerization catalyst and into contact with said oligomerization catalyst, operating said oligomerization zone at conditions effective to produce an effluent consisting essentially of 1-butene, 1-hexene, optionally heavier alpha olefins and unconverted ethylene if any, introducing the above effluent into a fractionation zone to recover a stream consisting essentially of 1-butene, a stream consisting essentially of 1-hexene, optionally a stream consisting essentially of heavier alpha olefins and an optional ethylene stream. In an advantageous embodiment the 1-hexene or at least one heavier alpha olefins, if any, are isomerized to an internal olefin and subsequently transformed by metathesis with the aid of additional ethylene into different alpha-olefins with even or odd number of carbons.

Abstract: Disclosed is a hydrocarbon conversion process in which an alkane component is catalytically converted in the presence of an oxygen or oxidizing component (i.e., oxidant). The hydrocarbon conversion process can be an oxidative coupling reaction, which refers to the catalytic conversion of alkane in the presence of oxidant to produce an olefin product, i.e., a composition containing C2+ olefin. Reverse-flow reactors can be used to carry out the oxidative coupling reaction.

Abstract: The invention relates to a method of producing olefinic monomers for the production of a polymer. The invention particularly relates to the production of tall oil-based biopolymers, such as polyolefins. In the stages of the method bio oil, with a content of over 50% of fatty acids of tall oil and no more than 25% of resin acids of tall oil, and hydrogen gas are fed into a catalyst bed (7); the oil is catalytically deoxygenated in the bed by hydrogen; the flow exiting the bed is cooled down and divided into a hydrocarbon-bearing liquid phase (10) and a gas phase; and the hydrocarbon-bearing liquid (13) is subjected to steam cracking (4) to provide a product containing polymerizing olefins. The deoxygenation in the bed can be followed by a catalytic cracking or, with a suitable catalyst, the deoxygenation and cracking can be simultaneous. The separated hydrogen-bearing gas phase can be circulated in the process.

Abstract: A liquid phase dehydrogenation process is described. The process includes reacting a liquid feed stream containing C10 to C28 paraffins and dissolved hydrogen in a dehydrogenation reaction zone in the presence of a dehydrogenation catalyst under liquid dehydrogenation conditions to dehydrogenate the paraffins to form a liquid dehydrogenation product stream comprising monoolefins, unreacted paraffins, and hydrogen, wherein the monoolefins in the product stream have 10 to 28 carbon atoms.

Abstract: The present invention relates to a management method for a wax fraction storage tank that stores a wax fraction produced by Fischer-Tropsch synthesis until the wax fraction is hydrocracked, the management method including maintaining the temperature inside the tank at 90° C. to 130° C. and maintaining the atmosphere inside the tank to be an inert gas atmosphere.

Abstract: Described herein are processes and related devices and systems for the conversion of higher hydrocarbons, such as in the form of waste plastics, petroleum sludge, slope oil, vegetable oil, and so forth, into lower hydrocarbons, which can be used as fuels or raw materials for a variety of industrial and domestic uses.

Abstract: The present invention provides a process for producing olefins, comprising: a. cracking an ethane-comprising feed in a cracking zone under cracking conditions to obtain at least olefins and hydrogen; b. converting an oxygenate feedstock in an oxygenate-to-olefin zone to obtain at least olefins; wherein at least part of the oxygenate feedstock is obtained by providing hydrogen obtained in step a) and a feed containing carbon monoxide and/or carbon dioxide to an oxygenate synthesis zone and synthesizing oxygenates. In another aspect the invention provides an integrated system for producing olefins.

Abstract: The invention relates to processes for converting a mixture of hydrocarbon and sulfur-containing molecules such as mercaptan into products comprising acetylene, ethylene, and hydrogen sulfide, to processes utilizing the acetylene and ethylene resulting from the conversion, and to equipment useful for such processes.

Abstract: An apparatus and method are provided for processing hydrocarbon feeds. The method enhances the conversion of hydrocarbon feeds into conversion products, such as ethylene. In particular, the present techniques utilize a high-severity thermal pyrolysis reactor that exposes a feed at a peak pyrolysis gas temperature ?1540° C. to produce a reactor product comprising ethylene and acetylene and has a C3+ to acetylene weight ratio ?0.5. Then, the method separates a product comprising tars and/or solids from at least a portion of the reactor product and converts at least a portion of the remaining reactor product into a conversion product, such as ethylene.

Abstract: Methods are provided for oligomerizing a dilute ethylene feed to form oligomers suitable for use as fuels and/or lubricant base oils. The fuels and/or lubricant base oils are formed by oligomerization of impure dilute ethylene with a zeolitic catalyst, where the zeolitic catalyst is resistant to the presence of poisons such as sulfur and nitrogen in the ethylene feed. The oligomers can also be formed in presence of diluents such as light paraffins.

Abstract: The process and apparatus converts ethylene in a dilute ethylene stream that may be derived from an FCC product to heavier hydrocarbons. The catalyst may be an amorphous silica-alumina base with a Group VIII and/or VIB metal. The catalyst is resistant to feed impurities such as hydrogen sulfide, carbon oxides, hydrogen and ammonia. At least 40 wt-% of the ethylene in the dilute ethylene stream can be converted to heavier hydrocarbons.

Abstract: The process and apparatus converts ethylene in a dilute ethylene stream that may be derived from an FCC product to heavier hydrocarbons. The catalyst may be an amorphous silica-alumina base with a Group VIII and/or VIB metal. The catalyst is resistant to feed impurities such as hydrogen sulfide, carbon oxides, hydrogen and ammonia. At least 40 wt-% of the ethylene in the dilute ethylene stream can be converted to heavier hydrocarbons.

Abstract: The present invention relates to a process for the conversion of an alcohol mixture (A) comprising about 20 w % to 100% isobutanol to make essentially propylene, comprising: a) introducing in a reactor (A) a stream comprising the mixture (A), optionally water, optionally an inert component, b) contacting said stream with a catalyst (A1) at a temperature above 450° C.

Abstract: A process and apparatus that uses a debutanizer with a side stripper can recover a light stream, an intermediate stream and a liquid stream. One of the intermediate stream and the liquid stream can be recycled to oligomerization or to fluid catalytic cracking.

Abstract: Catalytic forms and formulations are provided. The catalytic forms and formulations are useful in a variety of catalytic reactions, for example, the oxidative coupling of methane. Related methods for use and manufacture of the same are also disclosed.

Abstract: Methods and systems are provided for converting methane in a feed stream to acetylene. The method includes the further conversion of the acetylene to a hydrocarbon stream having olefins. The hydrocarbon stream is introduced into a supersonic reactor and pyrolyzed to convert at least a portion of the methane to acetylene. The reactor effluent stream is be treated to convert acetylene to another hydrocarbon, and in particular olefins. The method according to certain aspects includes controlling the level of contaminants in the hydrocarbon stream.

Abstract: The process and apparatus converts ethylene in a dilute ethylene stream that may be derived from an FCC product to heavier hydrocarbons. The catalyst may be an amorphous silica-alumina base with a Group VIII and/or VIB metal. The catalyst is resistant to feed impurities such as hydrogen sulfide, carbon oxides, hydrogen and ammonia. At least 40 wt-% of the ethylene in the dilute ethylene stream can be converted to heavier hydrocarbons.

Abstract: The present disclosure provides natural gas and petrochemical processing systems including oxidative coupling of methane reactor systems that integrate process inputs and outputs to cooperatively utilize different inputs and outputs of the various systems in the production of higher hydrocarbons from natural gas and other hydrocarbon feedstocks.

Abstract: A catalyst is described which comprises at least one IZM-2 zeolite, at least one matrix and at least one metal selected from metals from groups VIII, VIB and VIIB, said zeolite having a chemical composition expressed as the anhydrous base in terms of moles of oxides by the following general formula: XO2:aY2O3:bM2/nO, in which X represents at least one tetravalent element, Y represents at least one trivalent element and M is at least one alkali metal and/or alkaline-earth metal with valency n, a and b respectively representing the number of moles of Y2O3 and M2/nO; and a is in the range 0.001 to 0.5 and b is in the range 0 to 1.

Abstract: A simplified process for preparing polyolefins from saturated hydrocarbons is provided. The process involves partial and selective dehydrogenation of a saturated hydrocarbon in the presence of oxygen to form an olefin, unreacted hydrocarbon, and water, and optionally other by-products and oxygen. The water, other by-products (if present), and oxygen (if present) are separated from the olefin and unreacted hydrocarbon. No other separation is performed. The olefin and unreacted hydrocarbon are polymerized in the presence a polymerization catalyst or initiator to make polyolefin. Solid polyolefin is separated from unreacted hydrocarbon, which is recycled to the dehydrogenation reaction.

Abstract: The process and apparatus converts ethylene in a dilute ethylene stream that may be derived from an FCC product to heavier hydrocarbons. The catalyst may be an amorphous silica-alumina base with a Group VIII and/or VIB metal. The catalyst is resistant to feed impurities such as hydrogen sulfide, carbon oxides, hydrogen and ammonia. At least 40 wt-% of the ethylene in the dilute ethylene stream can be converted to heavier hydrocarbons.

Abstract: Disclosed herein are processes for producing and separating ethane and ethylene. In some embodiments, an oxidative coupling of methane (OCM) product gas comprising ethane and ethylene is introduced to a separation unit comprising two separators. Within the separation unit, the OCM product gas is separated to provide a C2-rich effluent, a methane-rich effluent, and a nitrogen-rich effluent. Advantageously, in some embodiments the separation is achieved with little or no external refrigeration requirement.

Abstract: The present invention provides a process for producing olefins from a feed comprising at least methane, ethane and carbon dioxide. The feed is separated into at least a methane-comprising feed, an ethane-comprising feed and a carbon dioxide-comprising feed. At least part of the methane-comprising feed is converted to a synthesis gas. The ethane-comprising feed is cracked to obtain at least olefins and hydrogen. At least part of the carbon dioxide-comprising feed and at least part of the synthesis gas are used to synthesis oxygenates. At least part of the oxygenates are converted in an oxygenate-to-olefin (OTO) zone to obtain at least olefins and hydrogen. At least part of the cracking effluent and at least part of the OTO zone effluent are combined to obtain a combined effluent from which hydrogen is separated. At least part of the hydrogen is supplied to the oxygenate synthesis zone.

Abstract: The present invention relates to a process for the conversion of an alcohols mixture (A) comprising about 20 w % to 100% isobutanol to make essentially propylene, comprising: a) introducing in a reactor (A) a stream comprising the mixture (A), mixed with a stream (D1) comprising olefins having 4 carbon atoms or more (C4+ olefins), optionally water, optionally an inert component, b) contacting said stream with a catalyst (A1) at a temperature above 500° C.

Abstract: The present invention relates to a method for producing a hydrocarbon product from coal and/or biomass comprising the following steps: converting the coal to a coal-oil and/or converting the biomass to bio-oil, optionally processing the coal-oil and/or bio-oil in a hydroprocessing reaction to remove one or more of oxygen, nitrogen or sulfur from hydrocarbon compounds in the coal-oil and/or bio-oil; and using at least a portion of the coal-oil and/or bio-oil as a feedstock in a cracking reaction to convert hydrocarbon compounds in the feedstock into a mixture of smaller hydrocarbon compounds comprising the hydrocarbon product.

Abstract: Process for the production of high-quality kerosene and diesel fuels and for the coproduction of hydrogen from a so-called light naphtha cut to which any quantity of LPG cut can be added where the steps of the process include: separating normal and iso-paraffins, dehydrogenation of the paraffins, oligomerization of the olefins and hydrogenation of the oligomerized olefins, the process permitting the production of kerosene and diesel fuels meeting market specifications, or even improved relative to the latter.

Abstract: The process converts FCC olefins to heavier compounds. The heavier compounds are more easily separated from the unconverted paraffins. The heavier compounds can be recycled to an FCC unit or delivered to a separate FCC unit. Suitable conversion zones are oligomerization and aromatic alkylation zones.

Abstract: Nanowires useful as heterogeneous catalysts are provided. The nanowire catalysts are prepared by polymer templated methods and are useful in a variety of catalytic reactions, for example, the oxidative coupling of methane to ethane and/or ethylene. Related methods for use and manufacture of the same are also disclosed.

Abstract: Isobutene, isoprene, and butadiene are obtained from mixtures of C4 and/or C5 olefins by dehydrogenation. The C4 and/or C5 olefins can be obtained by dehydration of C4 and C5 alcohols, for example, renewable C4 and C5 alcohols prepared from biomass by thermochemical or fermentation processes. Isoprene or butadiene can be polymerized to form polymers such as polyisoprene, polybutadiene, synthetic rubbers such as butyl rubber, etc. in addition, butadiene can be converted to monomers such as methyl methacrylate, adipic acid, adiponitrile, 1,4-butadiene, etc. which can then be polymerized to form nylons, polyesters, polymethylmethacrylate etc.

Abstract: A process for preparing poly alpha olefins from a Fisher-Tropsch product. The process comprising the steps of contacting a C5-C18 fraction of an alpha-olefinic hydrocarbon mixture produced from thermal cracking a C16-C40 Fisher-Tropsch product with an oligomerization catalyst under conditions to produce an oligomerized product; and fractionating the oligomerized product to obtain a fractionated product having an average carbon number greater than 30. A process for preparing lubricant base stocks from a Fisher-Tropsch product is also provided.

Abstract: Processes for upgrading condensate in a first hydrocarbon stream to provide distillate material may involve ionic liquid catalyzed olefin oligomerization of olefins in the first hydrocarbon stream to provide a first distillate enriched stream, dechlorination of the first distillate enriched stream, hydroprocessing at least one of a second and a third hydrocarbon stream to provide a second distillate enriched stream, and separation of a distillate product from the first and second distillate enriched streams.

Abstract: Process for the production of ethylene for chemical use starting with a hydrocarbon source according to which: a) the hydrocarbon source is subjected to a first cracking step, namely a pyrolysis step carried out in a cracking oven, thus producing a mixture of cracking products; b) the mixture of cracking products is subjected to a succession of treatment steps, including a compression step, which makes it possible to obtain a purified crude gas stream; c) the purified crude gas stream is then cooled to a temperature where hydrocarbons with 6 and more carbon atoms condense so that they can be removed from the purified crude gas stream; d) the resulting purified gas stream is afterwards supplied to one separating column, where a fraction A containing hydrogen, methane and ethylene is separated at the head of the column and a heavy fraction C is separated at the bottom of the column; e) a part of the reflux of this column is supplied to a refrigeration cycle leading to a fraction B enriched with ethylene; and f)

Abstract: The invention relates to a method of producing olefinic monomers for the production of a polymer. The invention particularly relates to the production of tall oil-based biopolymers, such as polyolefins. In the stages of the method bio oil, with a content of over 50% of fatty acids of tall oil and no more than 25% of resin acids of tall oil, and hydrogen gas are fed into a catalyst bed (7); the oil is catalytically deoxygenated in the bed by hydrogen; the flow exiting the bed is cooled down and divided into a hydrocarbon-bearing liquid phase (10) and a gas phase; and the hydrocarbon-bearing liquid (13) is subjected to steam cracking (4) to provide a product containing polymerizing olefins. The deoxygenation in the bed can be followed by a catalytic cracking or, with a suitable catalyst, the deoxygenation and cracking can be simultaneous. The separated hydrogen-bearing gas phase can be circulated in the process.

Abstract: A process for oligomerization of isobutene, the process including: feeding a hydrocarbon stream comprising n-butane, 1-butene, 2-butene, isobutane, and isobutene to a catalytic distillation reactor system comprising a hydroisomerization catalyst; feeding hydrogen to the catalytic distillation reactor system; concurrently in the catalytic distillation reactor system: contacting the 1-butene with the hydrogen in the presence of the hydroisomerization catalyst to convert at least a portion of the 1-butene to 2-butene; separating the isobutane and the isobutene from the n-butane and the 2-butene; recovering the isobutane and the isobutene from the catalytic distillation reactor system as an overheads fraction; recovering the n-butane and the 2-butene from the catalytic distillation reactor system as a bottoms fraction; contacting the overheads fraction in an oligomerization reaction system with an oligomerization catalyst to convert a portion of the isobutene to oligomers.

Abstract: A process (or steam cracking a hydrocarbon feedstock containing olefins to provide increased light olefins in the steam cracked effluent, the process comprising passing a first hydrocarbon feedstock containing one or more olefins through a reactor containing a crystalline silicate to produce an intermediate effluent with an olefin content of lower molecular weight than that of the feedstock, fractionating the intermediate effluent to provide a lower carbon fraction and a higher carbon fraction, and passing the higher carbon fraction, as a second hydrocarbon feedstock, through a stream cracker to produce a steam cracked effluent.

Abstract: The present invention relates to a process to make alpha olefins comprising: dehydrating ethanol to recover an ethylene stream, introducing said ethylene stream into an oligomerization zone containing an oligomerization catalyst and into contact with said oligomerization catalyst, operating said oligomerization zone at conditions effective to produce an effluent consisting essentially of 1-butene, 1-hexene, optionally heavier alpha olefins and unconverted ethylene if any, introducing the above effluent into a fractionation zone to recover a stream consisting essentially of 1-butene, a stream consisting essentially of 1-hexene, optionally a stream consisting essentially of heavier alpha olefins and an optional ethylene stream. In an advantageous embodiment the 1-hexene or at least one heavier alpha olefins, if any, are isomerized to an internal olefin and subsequently transformed by metathesis with the aid of additional ethylene into different alpha-olefins with even or odd number of carbons.

Abstract: It is an object of the present invention to provide an improved process whereby the yield structure of the components can be varied by a simple method, and the products can be produced stably and efficiently in a process for producing propylene and aromatic hydrocarbons from a hydrocarbon feedstock containing C4-12 olefins using a medium pore diameter zeolite-containing catalyst. A process for producing is disclosed which comprises a propylene production step wherein a specific zeolite catalyst is used to remove a C4+ hydrocarbon component from a reaction mixture, and part of the hydrocarbon component is recycled as necessary without modification, and an aromatic hydrocarbon production step wherein all or a part of the C4+ hydrocarbon component is used as the raw material.

Abstract: The present invention relates to a process for the producing propylene and ethylene from a light hydrocarbon stream comprising essentially ethane and butane. The process involves a non-catalytic cracking of ethane and normal-butane followed by a metathesis of ethylene and 2-butene to increase the propylene yield. Optionally the by-produced iso-butane is dehydrogenated and subsequently the produced iso-butene is converted to other valuable products like di-isobutylene, alkylate for gasoline blending tertiary-butyl-ethers, poly-isobutylene methyl-metacrylate or isoprene.

Abstract: Methods of oligomerizing hydrocarbons are disclosed. These methods include contacting olefins with an oligomerization catalyst in an oligomerization zone under oligomerization reaction conditions.

Abstract: A method of converting methanol feedstock to olefins is provided and includes contacting the methanol feedstock in a first conversion zone with a catalyst at reaction conditions effective to produce a first reaction zone effluent comprising DME, unreacted methanol and water, and recycling at least a portion of an overhead vapor product to the first conversion zone and/or to the second conversion zone.

Abstract: The present invention relates to a process for oligomerization/polymerization of ethylene and/or alpha-olefins, comprising the steps of oligomerizing/polymerizing ethylene and/or alpha-olefins to produce a reaction product which contains undesired reaction by-products, separating the reaction by-product from the reaction product as one or more reaction by-product fractions, and subjecting at least one of the reaction by-product fractions to steam cracking to produce a steam cracking product which comprises ethylene, which may be optionally purified and feed to the oligomerization/polymerization of ethylene and/or alpha olefins step.