Classifications

• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
  • C07C2/00—Preparation of hydrocarbons from hydrocarbons containing a smaller number of carbon atoms
  • C07C2/02—Preparation of hydrocarbons from hydrocarbons containing a smaller number of carbon atoms by addition between unsaturated hydrocarbons
  • C07C2/04—Preparation of hydrocarbons from hydrocarbons containing a smaller number of carbon atoms by addition between unsaturated hydrocarbons by oligomerisation of well-defined unsaturated hydrocarbons without ring formation
  • C07C2/06—Preparation of hydrocarbons from hydrocarbons containing a smaller number of carbon atoms by addition between unsaturated hydrocarbons by oligomerisation of well-defined unsaturated hydrocarbons without ring formation of alkenes, i.e. acyclic hydrocarbons having only one carbon-to-carbon double bond
  • C07C2/08—Catalytic processes
  • C07C2/12—Catalytic processes with crystalline alumino-silicates or with catalysts comprising molecular sieves
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
  • C07C7/00—Purification; Separation; Use of additives
  • C07C7/09—Purification; Separation; Use of additives by fractional condensation
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10G—CRACKING HYDROCARBON OILS; PRODUCTION OF LIQUID HYDROCARBON MIXTURES, e.g. BY DESTRUCTIVE HYDROGENATION, OLIGOMERISATION, POLYMERISATION; RECOVERY OF HYDROCARBON OILS FROM OIL-SHALE, OIL-SAND, OR GASES; REFINING MIXTURES MAINLY CONSISTING OF HYDROCARBONS; REFORMING OF NAPHTHA; MINERAL WAXES
  • C10G45/00—Refining of hydrocarbon oils using hydrogen or hydrogen-generating compounds
  • C10G45/32—Selective hydrogenation of the diolefin or acetylene compounds
  • C10G45/34—Selective hydrogenation of the diolefin or acetylene compounds characterised by the catalyst used
  • C10G45/36—Selective hydrogenation of the diolefin or acetylene compounds characterised by the catalyst used containing nickel or cobalt metal, or compounds thereof
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10G—CRACKING HYDROCARBON OILS; PRODUCTION OF LIQUID HYDROCARBON MIXTURES, e.g. BY DESTRUCTIVE HYDROGENATION, OLIGOMERISATION, POLYMERISATION; RECOVERY OF HYDROCARBON OILS FROM OIL-SHALE, OIL-SAND, OR GASES; REFINING MIXTURES MAINLY CONSISTING OF HYDROCARBONS; REFORMING OF NAPHTHA; MINERAL WAXES
  • C10G45/00—Refining of hydrocarbon oils using hydrogen or hydrogen-generating compounds
  • C10G45/32—Selective hydrogenation of the diolefin or acetylene compounds
  • C10G45/34—Selective hydrogenation of the diolefin or acetylene compounds characterised by the catalyst used
  • C10G45/40—Selective hydrogenation of the diolefin or acetylene compounds characterised by the catalyst used containing platinum group metals or compounds thereof
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10G—CRACKING HYDROCARBON OILS; PRODUCTION OF LIQUID HYDROCARBON MIXTURES, e.g. BY DESTRUCTIVE HYDROGENATION, OLIGOMERISATION, POLYMERISATION; RECOVERY OF HYDROCARBON OILS FROM OIL-SHALE, OIL-SAND, OR GASES; REFINING MIXTURES MAINLY CONSISTING OF HYDROCARBONS; REFORMING OF NAPHTHA; MINERAL WAXES
  • C10G50/00—Production of liquid hydrocarbon mixtures from lower carbon number hydrocarbons, e.g. by oligomerisation
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10G—CRACKING HYDROCARBON OILS; PRODUCTION OF LIQUID HYDROCARBON MIXTURES, e.g. BY DESTRUCTIVE HYDROGENATION, OLIGOMERISATION, POLYMERISATION; RECOVERY OF HYDROCARBON OILS FROM OIL-SHALE, OIL-SAND, OR GASES; REFINING MIXTURES MAINLY CONSISTING OF HYDROCARBONS; REFORMING OF NAPHTHA; MINERAL WAXES
  • C10G69/00—Treatment of hydrocarbon oils by at least one hydrotreatment process and at least one other conversion process
  • C10G69/02—Treatment of hydrocarbon oils by at least one hydrotreatment process and at least one other conversion process plural serial stages only
  • C10G69/12—Treatment of hydrocarbon oils by at least one hydrotreatment process and at least one other conversion process plural serial stages only including at least one polymerisation or alkylation step
  • C10G69/126—Treatment of hydrocarbon oils by at least one hydrotreatment process and at least one other conversion process plural serial stages only including at least one polymerisation or alkylation step polymerisation, e.g. oligomerisation
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
  • C07C2529/00—Catalysts comprising molecular sieves
  • C07C2529/04—Catalysts comprising molecular sieves having base-exchange properties, e.g. crystalline zeolites, pillared clays
  • C07C2529/06—Crystalline aluminosilicate zeolites; Isomorphous compounds thereof
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10G—CRACKING HYDROCARBON OILS; PRODUCTION OF LIQUID HYDROCARBON MIXTURES, e.g. BY DESTRUCTIVE HYDROGENATION, OLIGOMERISATION, POLYMERISATION; RECOVERY OF HYDROCARBON OILS FROM OIL-SHALE, OIL-SAND, OR GASES; REFINING MIXTURES MAINLY CONSISTING OF HYDROCARBONS; REFORMING OF NAPHTHA; MINERAL WAXES
  • C10G2300/00—Aspects relating to hydrocarbon processing covered by groups C10G1/00 - C10G99/00
  • C10G2300/10—Feedstock materials
  • C10G2300/1088—Olefins
  • C10G2300/1092—C2-C4 olefins
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10G—CRACKING HYDROCARBON OILS; PRODUCTION OF LIQUID HYDROCARBON MIXTURES, e.g. BY DESTRUCTIVE HYDROGENATION, OLIGOMERISATION, POLYMERISATION; RECOVERY OF HYDROCARBON OILS FROM OIL-SHALE, OIL-SAND, OR GASES; REFINING MIXTURES MAINLY CONSISTING OF HYDROCARBONS; REFORMING OF NAPHTHA; MINERAL WAXES
  • C10G2300/00—Aspects relating to hydrocarbon processing covered by groups C10G1/00 - C10G99/00
  • C10G2300/40—Characteristics of the process deviating from typical ways of processing
  • C10G2300/4081—Recycling aspects
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10G—CRACKING HYDROCARBON OILS; PRODUCTION OF LIQUID HYDROCARBON MIXTURES, e.g. BY DESTRUCTIVE HYDROGENATION, OLIGOMERISATION, POLYMERISATION; RECOVERY OF HYDROCARBON OILS FROM OIL-SHALE, OIL-SAND, OR GASES; REFINING MIXTURES MAINLY CONSISTING OF HYDROCARBONS; REFORMING OF NAPHTHA; MINERAL WAXES
  • C10G2400/00—Products obtained by processes covered by groups C10G9/00 - C10G69/14
  • C10G2400/06—Gasoil
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10G—CRACKING HYDROCARBON OILS; PRODUCTION OF LIQUID HYDROCARBON MIXTURES, e.g. BY DESTRUCTIVE HYDROGENATION, OLIGOMERISATION, POLYMERISATION; RECOVERY OF HYDROCARBON OILS FROM OIL-SHALE, OIL-SAND, OR GASES; REFINING MIXTURES MAINLY CONSISTING OF HYDROCARBONS; REFORMING OF NAPHTHA; MINERAL WAXES
  • C10G2400/00—Products obtained by processes covered by groups C10G9/00 - C10G69/14
  • C10G2400/08—Jet fuel

Definitions

• the present invention relates to a process for producing middle distillates, in particular kerosene and/or gas oil, meeting the specifications in force, in particular those defined in standard ASTM D1655 or ASTM D7566 for kerosene and those defined in standard ASTM D975 or European standard 15940 for diesel, by heterogeneous oligomerization of an olefinic feedstock, in particular a biosourced olefinic feedstock.
• Patent FR 2926812 thus discloses a process for the oligomerization of olefins, allowing the production of fuel, for example the production of gasoline and/or kerosene from light olefinic feedstocks containing between 2 and 8 carbon atoms (C2- C8), and in particular from light olefinic feeds containing high proportions of propylene and/or butenes and/or pentenes and using an oligomerization catalyst based, preferably consisting solely, of silica-alumina with reduced content in macropores.
• fuel for example the production of gasoline and/or kerosene from light olefinic feedstocks containing between 2 and 8 carbon atoms (C2- C8), and in particular from light olefinic feeds containing high proportions of propylene and/or butenes and/or pentenes
• an oligomerization catalyst based preferably consisting solely, of silica-alumina with reduced content in macropores
• Patent EP 1 396 532 describes a process for procurzing a liquid hydrocarbon feed, comprising: a) the separation from said hydrocarbon feed of a fraction (01) essentially comprising compounds containing 5 carbon atoms C5) including at least 2% by weight of pentenes; b) bringing said fraction (01) into contact with a cut of hydrocarbons (02) comprising hydrocarbons having a number of carbon atoms of between 6 and 10 (C6-C10), including at least 2% by weight of olefins, in the presence of an acid catalyst promoting the dimerization and alkylation reactions of the species; c) separation of the effluent obtained into at least two cuts including a gasoline cut (a) whose upper distillation point is less than 100°C and comprising the majority of the reagents not having reacted, and a kerosene cut ( ) with a distillation interval of between 100°C and 300°C.
• Patent EP 1 602 637 describes a process making it possible in a simple and economical way to modulate the respective production of gasoline and diesel, by transforming the initial charge of hydrocarbons comprising from 4 to 15 carbon atoms (C4-C15) into one gasoline fraction with an improved octane number compared to that of the feed and a diesel fraction with a high cetane number.
• Patent EP 1 739 069 describes a process for preparing a gas oil cut from an olefinic feedstock with 2-12 carbon atoms (C2-C12), comprising two oligomerization steps between which a separation step is inserted. .
• the intermediate separation step makes it possible to obtain a light cut of C4-C5 olefinic hydrocarbons, an intermediate cut having a T95 between 180°C and 240°C and a heavy cut of T95 greater than 240°C.
• the intermediate cut is then mixed with at least a fraction of the light cut in a mass ratio (intermediate cut / light cut) of between 60/40 and 80/20 and then undergoes a second oligomerization
• Patent EP 2 385 092 describes a process for producing middle distillate hydrocarbon bases from ethanol, more particularly bioethanol.
• Patent EP 2 707 462 discloses a process for the oligomerization of olefins comprising from 4 to 6 carbon atoms (C4-C6) in a middle distillate cut having predominantly 10 to 20 carbon atoms (C10-C20).
• the starting olefinic charge must contain a minimum of branched olefins (or iso-olefins), preferably at least 10% by weight and preferably 20% by weight of iso-olefins relative to to all of the olefins in the feed.
• Patent FR 2 959 750 describes a process for producing middle distillate hydrocarbon bases, preferably kerosene hydrocarbon base, from an ethanol feedstock derived from biomass, said process comprising the dehydration of the ethanol into a predominantly ethylenic effluent , two successive stages of oligomerization to obtain a middle distillate effluent.
• Patent FR 3 053 355 describes a process for the oligomerization of light olefinic charges containing between 2 and 10 carbon atoms (C2-C10) per molecule, using a catalytic system comprising a catalyst based on silica alumina and a catalyst based on zeolite having pore openings of 10 or 12 oxygen atoms, and used at a temperature between 130 and 350°C, at a pressure between 0.1 and 10 MPa and at a WH (hourly volume velocity) between between 0.1 and 5 a.m. 1 .
• the process of EP 3 053 355 makes it possible to improve the yield of middle distillates and in particular the yield of gas oil, compared to an oligomerization process using only one of the catalysts of the catalytic system used, at iso-volume of catalyst.
• US patent 6,372,949 describes the transformation of oxygenates into gasoline and distillates (C4-C12 cut) in a single dehydration-oligomerization step using a composite catalyst comprising a one-dimensional zeolite 10 MR chosen from the group formed by ZSM 22, ZSM 23 , ZSM 35, ZSM 48, ZSM 57 and ferrierite and mixtures thereof, with a multidimensional zeolite having a medium pore size, such as ZSM-5 zeolite.
• a composite catalyst comprising a one-dimensional zeolite 10 MR chosen from the group formed by ZSM 22, ZSM 23 , ZSM 35, ZSM 48, ZSM 57 and ferrierite and mixtures thereof, with a multidimensional zeolite having a medium pore size, such as ZSM-5 zeolite.
• the present invention relates to a process for preparing middle distillates from an olefinic feedstock, comprising: a) an oligomerization step supplied with at least the olefinic feedstock, a first recycle and a second recycle, and carried out in the presence of at least one oligomerization catalyst, at a temperature between 20 and 500°C, a pressure between 1.0 and 10 MPa and a WH between 0.1 and 0.5 h' 1 , to produce a reaction effluent comprising dimers, trimers and oligomers; b) a step of fractionating the reaction effluent obtained at the end of step a), into at least:
• a recycling step comprising the preparation of a first recycle comprising at least part of the light fraction; the preparation of a second recycle comprising at least part of the intermediate fraction; and transferring the first recycle and the second recycle to step a) of oligomerization; d) a step of hydrogenation of at least part of the heavy fraction separated in step b) in the presence of hydrogen, to obtain a hydrogenated heavy fraction comprising middle distillates.
• the advantage of the process according to the invention is to provide a process for the efficient conversion of light olefinic feedstocks, in particular comprising olefins with between 3 and 6, preferably between 3 and 4, carbon atoms, and more particularly at least in biosourced part, to selectively produce a middle distillate cut, and more particularly a kerosene cut or a diesel cut, meeting the specifications in force and in particular the specifications of standard ASTM D7566 or European standard 15940 respectively.
• the process according to the invention also makes it possible to greatly improve the selectivity for middle distillates, or more particularly for kerosene or diesel, compared to the oligomerization processes of the state of the art, and therefore to maximize the yields of middle distillates. , more particularly in kerosene or diesel, while maintaining an overall conversion of the initial olefinic charge that is satisfactory, or even high.
• Another advantage of the process according to the invention lies in the fact that any type of feedstock and in particular biosourced olefinic feedstocks which typically comprise a high proportion of olefins and are therefore very reactive, can be converted into hydrocarbon products and in particular with high yields of middle distillates, and more particularly of kerosene or diesel.
• the expressions "between ... and " and “between .... and " are equivalent and mean that the limit values of the interval are included in the range of values described . If this is not the case and the limit values are not included in the range described, such precision will be provided by the present invention.
• the different parameter ranges for a given step such as the pressure ranges and the temperature ranges can be used alone or in combination.
• a range of preferred pressure values can be combined with a range of more preferred temperature values.
• upstream and downstream are to be understood according to the general flow of the flow(s) in question in the process.
• biosourced means that the material/product/compound that it qualifies is an organic material/product/compound whose carbon comes from CO2 present in the atmosphere recently fixed (on a human scale) thanks to energy solar (photosynthesis). On land, this CO2 is captured or fixed by plant life (for example, agricultural crops or forest materials). In the oceans, CO2 is captured or fixed by photosynthesizing bacteria or phytoplankton. For example, a biosourced material has a 14 C/ 12 C isotopic ratio greater than 0. Conversely, a material of fossil origin has a 14 C/ 12 C isotopic ratio of approximately 0.
• the terms “renewable” or “from renewable sources” can also be used.
• its modern carbon content or percent modem carbon, pMC, according to the Anglo-Saxon term
• ASTM D 6866-21 Determination of biosourced content materials from the natural range using radiocarbon and isotopic ratio mass spectrometry analysis.
• the method of this standard measures the 14 C/ 12 C isotope ratio in a sample and compares it to the 14 C/ 12 C isotope ratio of a standard biosourced reference to obtain the percentage of biosourced content of the sample, the reference giving a radiocarbon content approximately equivalent to the atmospheric radiocarbon fraction in 1950.
• the pMC of the standard biosourced reference material is therefore equal to 100%.
• the pMC of a biosourced material is strictly greater than 0%, for example greater than or equal to 1%.
• the pMC of a material of fossil origin is approximately 0%.
• a current biosourced material can therefore also possibly have a pMC greater than 100%.
• T95 or “temperature T95” are interchangeable and designate the temperature at which 95% by weight of the product considered is evaporated. It is determined according to the standardized ASTM D2887 method.
• T5 or “T5 temperature” is the temperature at which 5% by weight of the product considered is evaporated, determined according to the same standardized ASTM D2887 method.
• Cx designates compounds containing x carbon atoms.
• a chemical compound C3 contains 3 carbon atoms.
• the term “Cx+” designates compounds having at least x carbon atoms.
• C9+ compounds are compounds containing at least 9 carbon atoms (i.e. 9 or more carbon atoms).
• the term “Cx-” designates compounds having at most x carbon atoms.
• groups of chemical elements are described according to the new IUPAC classification.
• groups 9 or 10 correspond to the metals respectively in columns 9 and 10 according to the IUPAC classification or to the last two columns of group VIIIB according to the CAS classification (CRC Handbook of Chemistry and Physics, CRC editor press, editor-in-chief DR Lide, 81st edition, 2000-2001).
• group 6 corresponds to the metals of column 6 according to the IUPAC classification or to the metals of columns VI B according to the CAS classification.
• the terms “olefin” and “mono-olefin” are used interchangeably and refer to hydrocarbons comprising a double bond.
• the olefins of the olefinic feedstock of the process comprise between 3 and 6 carbon atoms (C3-C6), preferably 3 and/or 4 carbon atoms (C3 and/or C4).
• the olefins obtained after oligomerization preferably comprise between 6 and 30 carbon atoms (C6-C30), preferably between 9 and 25 carbon atoms (C9-C25), in particular between 9 and 16 carbon atoms (C9-C16). ) or between 10 and 25 carbon atoms (C10-C25).
• oligomerization designates any reaction of addition of an olefin to another olefin, until compounds are obtained, in particular hydrocarbon compounds in particular mono-olefins, typically containing between 6 and 30 atoms of carbon, preferably between 9 and 25 carbon atoms (C9-C25), in particular 9 and 16 carbon atoms (C9-C16) or between 10 and 25 carbon atoms (C10-C25).
• the products obtained are dimers or trimers of the olefins of the olefinic feedstock, that is to say olefinic compounds resulting from the condensation of respectively two or three molecules of olefins of the olefinic feedstock, or oligomers which correspond to olefinic compounds resulting from the condensation of several olefin molecules of the olefinic charge (several here meaning more than 3 but less than 10, preferably less than or equal to 5, preferably less than or equal to 4).
• oligomers are obtained whose number of carbon atoms is largely less than or equal to 30, and for the majority preferably between 9 and 25, in particular between 9 and 16 or between 10 and 25.
• Oligomerization is distinguished from polymerization by an addition of molecules in limited number.
• the number of molecules adding up is in the context of the invention between 2 and 10, limits included, preferably between 3 and 6, and even more preferably between 3 and 6.
• the oligomers can however include traces of olefins. having been oligomerized with a number of molecules greater than 10. Most often, these traces represent less than 5% by weight relative to the oligomers formed.
• heterogeneous catalysis defines, in this presentation, a reaction, in particular oligomerization reactions, where at least two phases coexist, the catalyst being in solid form.
• the oligomerization step of the process according to the invention implements the oligomerization of the olefinic charge by heterogeneous catalysis, that is to say in the presence of a catalyst in solid form, the charge and advantageously the products obtained are preferably in the liquid phase.
• the present invention relates to a process for preparing middle distillates, preferably a kerosene cut and/or a gas oil cut, from a C3 to C6 olefinic feed, preferably C3 to C4 and in particular in C3, in C4 or their mixtures, comprising, preferably consisting of: a') optionally a step of pretreatment of the olefinic feed preferably implementing at least one adsorption section, a water washing section , a hydrotreatment section and/or a selective hydrogenation section; a”) optionally a step of separating the olefinic feedstock to at least partially separate the C5 and C6 compounds present in said olefinic feedstock; a) an oligomerization step supplied at least by the olefinic feedstock, optionally pretreated and/or separated, a first recycle and a second recycle, and carried out, preferably in the liquid phase, in the presence of at least one oligomerization catalyst preferably solid, at a temperature
• a recycling step comprising: the preparation of a first recycle comprising, preferably consisting of, at least part of the light fraction resulting from fractionation step b); the preparation of a second recycle comprising, preferably consisting of, at least part of the intermediate fraction resulting from fractionation step b); and transferring the first recycle and the second recycle to step a) of oligomerization; d) a step of hydrogenating at least part of the heavy fraction separated in step b) in the presence of hydrogen, to obtain a hydrogenated heavy fraction advantageously comprising at least one middle distillate cut; e) optionally a step of separating the heavy hydrogenated fraction, to obtain at least one middle distillate cut, in particular a kerosene cut and/or a gas oil cut.
• the olefinic charge comprising: the preparation of a first recycle comprising, preferably consisting of, at least part of the light fraction resulting from fractionation step b); the preparation of a second recycle comprising, preferably consisting of, at least part of the intermediate fraction
• the feed treated by the process according to the invention is advantageously a so-called light olefinic feed, that is to say comprising hydrocarbon compounds and in particular olefins, preferably mono-olefins, containing between 3 and 6 carbon atoms. (i.e. C3, C4, C5 and C6), preferably between 3 and 4 carbon atoms (i.e. C3 and C4), preferably 3 or 4 carbon atoms (i.e. i.e. C3 or C4).
• the C3 to C6 olefinic filler comprises at least 20% by weight, preferably at least 50% by weight, preferably at least 90% by weight of olefins, preferably at least 95% by weight of olefins, in in particular at least 98% of olefins or at least 99% by weight of olefins, relative to the total weight of the olefinic charge relative to the total weight of the C3 to C6 olefinic charge, the olefins containing between 3, 4, 5 and 6 carbon atoms, preferably 3 and/or 4 carbon atoms, said olefins preferably being mono-olefins.
• the olefinic feed may optionally comprise paraffins, in particular paraffins of the different cuts at the terminals of the initial and final distillation points of the feed considered, in particular at C3 to C6, that is to say fully hydrogenated hydrocarbon compounds, preferably aliphatic preferably containing between 3 and 6 carbon atoms.
• the olefinic filler may optionally comprise up to 80% by weight, preferably up to 50% by weight, preferably up to 10% by weight, preferably up to 5% by weight, in particular up to 2% by weight.
• the olefinic filler is devoid of paraffins, that is to say it comprises less than 0.5% by weight of paraffins, and preferably less than 0.1% by weight of paraffins, relative to the total weight of the olefinic charge.
• the preferred olefinic fillers contain mainly propylene and/or butenes and/or pentenes, preferably propylene and/or butenes (iso-butene and/or n-butenes).
• propylene and/or butenes iso-butene and/or n-butenes.
• An olefinic filler particularly suitable for the process according to the invention is an olefinic filler essentially in C3 and C4, preferably in C3 or C4, that is to say at least 90% by weight, preferably at least 95% by weight, of preferably at least 98% by weight of C3 and/or C4 olefins relative to the total weight of the olefins contained in the olefinic feedstock.
• the olefinic filler advantageously comprises at least 85% by weight of propylene and/or butenes (in particular isobutene and/or n-butenes), preferably at least 90% by weight, preferably at least 95% by weight, preferably at least 95% by weight.
• the olefinic filler can in particular be chosen from a “polymer grade” propylene filler (“propylene polymer grade” according to Anglo-Saxon terminology), a filler essentially comprising propylene (that is to say at least 90% by weight of propylene) and a small quantity of butenes (i.e. less than 10% by weight of butenes), a filler consisting essentially of isobutene (i.e.
• isobutene at least 90% by weight of isobutene
• a filler consisting essentially of n-butenes (but-1-ene and but-2-ene) (that is to say at least 90% by weight of but-1-ene and but-2-ene), and their mixtures.
• said olefinic filler may also contain C5 and/or C6 compounds.
• the content of C5 and/or C6 compounds is preferably less than or equal to 5% by weight in the olefinic feedstock, preferably preferably less than or equal to 2% by weight, or even preferably less than or equal to 1% by weight relative to the weight of the olefinic filler.
• the C5 and/or C6 olefin content of the olefinic feedstock is preferably less than 0.8% by weight, preferably less than 0.6% by weight.
• the olefinic filler of this preferred embodiment may also comprise paraffins, in particular propane and/or butane.
• the C3 and/or C4 olefinic filler is devoid of propane and/or butane (that is to say, comprises less than 0.5% by weight of paraffins, and preferably less than 0.1% by weight of paraffins, relative to the total weight of the olefinic feedstock), which makes it possible to carry out the oligomerization step at a lower pressure compared to the oligomerization of a feedstock comprising paraffins.
• the olefinic filler is free of C5 and/or C6 paraffins, that is to say it comprises less than 0.5% by weight, preferably less than 0.1% by weight of C5 and/or C6 paraffins. or C6, in order to limit the quantity of inert compounds introduced in particular in step a).
• a preferred olefinic feedstock is an olefinic C4 cut, which comprises at least 98% by weight of n-butenes 1-butene and 2-butene, preferably less than 2% of n-butane, and preferably less than 0.5% n-butane, the percentages being given in relation to the total weight of the olefinic charge.
• Another preferred olefinic filler is an olefinic C4 cut, which in particular comprises at least 90% by weight of isobutene, or even at least 92% by weight of isobutene, and in particular at most 97% by weight of isobutene, and optionally butane and/or isobutane and/or n-butenes, in particular between 3 and 10% by weight of butane and/or isobutane and/or n-butenes, the percentages being given in relation to the total weight of the olefinic charge.
• the olefinic filler can also be an olefinic C3-C4 cut (that is to say comprising propylene and butenes), comprising for example at least 90% by weight of propylene and up to 10% by weight of butenes, said filler being preferably free of paraffins (that is to say comprising less than 0.5% by weight of paraffins, preferably less than 0.1% by weight of paraffins), the percentages being given in relation to the total weight of the olefinic charge .
• an olefinic C3-C4 cut that is to say comprising propylene and butenes
• paraffins that is to say comprising less than 0.5% by weight of paraffins, preferably less than 0.1% by weight of paraffins
• Another preferred olefinic filler is an olefinic C3 cut, preferably comprising at least 90% by weight of propylene, preferably at least 98% by weight of propylene. It may include propane, preferably up to 2% by weight of propane.
• the olefinic feedstock is at least partly, very advantageously entirely, biosourced, in order to produce valuable biosourced products.
• the C3 to C6 olefinic feedstock preferably C3 and/or C4, may in particular come from a Fischer Tropsch unit, an olefin production unit from methanol and/or a dehydration unit.
• alcohols for example isobutanol, in particular from biomass, for example from the fermentation of sugars.
• the olefinic feed can also come from a conventional unit.
• it is preferably implemented in mixture with fillers of biosourced origin, preferably in weight proportions between a conventional olefinic filler relative to a biosourced olefinic filler between 90:10 and 10:90, preferably between 80:20 and 20:80.
• a conventional olefinic feedstock comes from a steam cracking unit, an FCC catalytic cracking unit (FCC for Fluid Catalytic Cracking according to Anglo-Saxon terminology), a unit for selective hydrogenation of diolefins (called SHU unit), or dehydrogenation of paraffins, pure or mixed and/or any other unit leading to the production of light olefins.
• the olefinic feedstock treated in the process according to the invention can advantageously undergo a pretreatment step before being sent to step a) of oligomerization.
• a pretreatment step makes it possible to eliminate any compound that could cause poisoning of the oligomerization catalysts, in particular basic nitrogen compounds, water, sulfur derivatives, basic nitrogen derivatives.
• the olefinic filler is free of sulfur or sulfur compounds, that is to say comprises a content less than or equal to 20 ppm by weight, preferably less than or equal to 12 ppm by weight, preferably less than or equal to 10 ppm by weight of sulfur relative to the weight of the olefinic feedstock, making it possible to avoid or at least limit poisoning of the oligomerization catalyst of step a). If the olefinic feed contains sulfur (i.e.
• the process advantageously comprises a step of pretreatment of the olefinic feed, located upstream of step a) of oligomerization, preferably implementing a section adsorption and/or a water washing section and/or a dedicated hydrotreatment section, thus making it possible to protect the oligomerization catalyst of step a).
• the feed of the process according to the invention is devoid of nitrogen or nitrogen compounds, that is to say comprises a content less than or equal to 0.1 ppm by weight of nitrogen element relative to the total weight of the olefinic charge, making it possible to avoid or at least limit poisoning of the oligomerization catalyst of step a).
• the process advantageously comprises a step of pretreatment of the olefinic feedstock, located upstream of step a) of oligomerization, preferably implementing an adsorption and/or washing section with water and/or hydrotreatment, thus making it possible to protect the oligomerization catalyst of step a).
• the olefinic feedstock treated by the process according to the invention is free of butadiene, in particular of 1,3-butadiene, that is to say comprises a content less than or equal to 0.1% by weight, of preferably less than or equal to 500 ppm weight of butadiene, in particular 1,3-butadiene, relative to the total weight of the olefinic charge, which makes it possible to protect the oligomerization catalyst.
• the process advantageously comprises a step of pretreatment of the olefinic feed, located upstream of step a) of oligomerization, putting preferably implement a selective hydrogenation section.
• the process may comprise an optional step of separation of the olefinic charge, advantageously located upstream of step a) of oligomerization, in order to at least partially separate the C5 compounds and C6 present in said olefinic feedstock.
• This optional separation step thus makes it possible to produce a fraction comprising the C5 and C6 compounds possibly present in the feed and at least one fraction comprising the C3 and C4 compounds.
• Those skilled in the art can adjust the separation so as to push the splitting more or less and separate fraction comprising the C3 and C4 compounds in a C3 fraction (in particular enriched in C3, in particular in propylene) and a C4 fraction (in particular enriched in C4, in particular in isobutene and/or in n-butenes).
• this optional separation step makes it possible to concentrate the load in compounds, particularly C3 and/or C4 olefinic compounds.
• the fraction comprising the C3 and C4 compounds, the C3 fraction or the C4 fraction is then advantageously sent to step a) of oligomerization, preferably directly.
• the fraction comprising the C5 and C6 compounds can be purged and recovered, for example by being integrated into a gasoline pool.
• the process can comprise an optional step of separation of the olefinic charge, located upstream of step a) of oligomerization, to separate at least one C3 fraction and one C4 fraction. , the two fractions, that in C3 and that in C4, each undergoing in parallel steps a), b) and c) and possibly d), and the heavy fractions can be re-mixed at the end of step c ) or possibly at the end of step d) of hydrogenation.
• the process according to the invention comprises an oligomerization step, more particularly implementing a heterogeneous oligomerization reaction (or called heterogeneous catalysis), carried out in the presence of at least one oligomerization catalyst, to produce a reaction effluent comprising dimers, trimers and oligomers.
• a heterogeneous oligomerization reaction or called heterogeneous catalysis
• this step a) of oligomerization makes it possible to obtain a mixture of hydrocarbons containing mono-olefins with a number of carbon atoms predominantly greater than or equal to 6, preferably greater than or equal to 8, preferably greater than or equal to equal to 9, the term "mainly” here meaning at least 90% by weight of C6+ hydrocarbons, preferably C8+, preferably C9+, relative to the weight of the mixture of hydrocarbons obtained.
• the resulting hydrocarbon mixture may also include unreacted C3 to C6 feedstock olefins.
• step a) of oligomerization is fed at least by the olefinic feedstock, optionally pretreated and/or optionally separated.
• step a) of oligomerization is also supplied by a first recycle comprising, preferably consisting of, at least part of the light fraction resulting from step b), said first recycle is advantageously prepared then transferred to step a) into step c).
• oligomerization step a) is also supplied by a second recycle comprising, preferably consisting of, at least part of the intermediate fraction resulting from step b), said first recycle is advantageously prepared then transferred to step a) into step c).
• step a) of oligomerization is carried out, preferably in the liquid phase (that is to say the olefinic feedstock and the products formed are in liquid form under the temperature and pressure conditions used), in the presence of an oligomerization catalyst, preferably solid.
• oligomerization step a) is carried out at a temperature between 20 and 500°C, at a pressure between 1.0 and 10 MPa, and with a WH preferably between 0.1 and 0. 5 h'1 , preferably between 0.2 and 0.3 h'1 .
• the WH (or hourly volumetric speed) is, according to the invention, defined by the ratio between the volume flow rate of fresh olefinic feedstock in particular at 15°C and 1 atm and the volume of oligomerization catalyst in particular in operation (called still in operation).
• the temperature at which oligomerization step a) is carried out between 20 and 500°C, advantageously corresponds to the temperature at the inlet of step a), preferably at the inlet of the reactor implemented in step a). .
• the operating conditions of temperature, pressure and hourly volume velocity can be adjusted by those skilled in the art depending in particular on the composition of the olefinic feedstock and the nature of the oligomerization catalyst used, to maximize the yields of middle distillates, in particular the yields of kerosene or diesel.
• step a) uses at least one oligomerization catalyst, preferably between one and three different oligomerization catalysts, preferably one oligomerization catalyst.
• Any type of oligomerization catalyst known to those skilled in the art can be used as an oligomerization catalyst in step a).
• the oligomerization catalyst(s) of step a) can be any type of acid catalyst, in particular chosen from catalysts based on phosphoric acid impregnated on silica (supported phosphoric acid, known as SPA type), ion exchange resins, alumina silicas and pure or supported zeolites on alumina support.
• the oligomerization catalyst(s) of step a) is(are) chosen from ion exchange resins, preferably cation exchange resins, alumina silicas (i.e. i.e. comprising silica and alumina) and zeolites pure or supported on alumina support.
• ion exchange resins preferably cation exchange resins
• alumina silicas i.e. i.e. comprising silica and alumina
• zeolites pure or supported on alumina support zeolites pure or supported on alumina support.
• step a) is preferably carried out at a temperature, advantageously at the inlet, between 100 and 300°C, preferably between 160 and 250°C, and at a pressure preferably between 1.5 and 6.5 MPa, preferably between 1.5 and 4.0 MPa.
• Zeolite-based catalysts are particularly suitable for producing linear or loosely branched heavy olefins, which in particular allow the production of high quality gas oil, that is to say, after hydrogenation, having a cetane number greater than 45.
• step a) is preferably carried out at a temperature, advantageously at the inlet, between 150 and 500°C, preferably between 200 and 350°C, at a pressure preferably between 2.0 and 10.0 MPa, preferably between 3.0 and 6.5 MPa.
• the zeolite-based oligomerization catalyst comprises at least one zeolite selected from the group consisting of aluminosilicate type zeolites having an overall Si/AI atomic ratio greater than 10 and a pore structure 8, 10 or 12MR.
• Said zeolite is more preferably selected from the group consisting of zeolites of structural type ferrierite, chabazite, Y and US-Y, ZSM-5, ZSM-12, NU-86, mordenite, ZSM-22, NU-10, ZBM-30, ZSM-11, ZSM-57, ZSM-35, IZM-2, ITQ-6 and IM-5, SAPO, and mixtures thereof.
• said zeolite is selected from the group consisting of ferrierite, ZSM-5, Mordenite, ZSM-22 zeolites, and their mixtures. Even more preferably, the zeolite used is ZSM-5.
• Ion exchange resin catalysts are chosen for their good mechanical strength in the temperature and pressure ranges used in step a).
• step a) is preferably carried out at a temperature, advantageously at the inlet, between 20°C to 250°C, preferably between 70°C and 180°C. °C, and at a pressure preferably between 2.0 and 10.0 MPa, preferably between 3.0 and 6.5 MPa.
• Catalysts such as ion exchange resins, inexpensive and non-regenerable, have the advantage of having acceptable cycle times in a fixed bed operation because they are less sensitive to contaminants than zeolites and alumina silicas.
• the ion exchange resin type catalyst used in step a) is a co-polymer of aromatic monovinyl and aromatic polyvinyl, preferably a copolymer of divinyl benzene and styrene, preferably sulfonated, in particular having a crosslinking rate of between 20 and 45%, preferably between 30 and 40%, and preferably equal to 35%, and an acid strength, representing the number of active sites of said resin, determined by dosage, preferably by conductimetry, H+ ions released by the acid resin after exchange with Na+ ions (see ASTM D4266), between 1 and 10 mmol H+ equivalent per gram and preferably between 3.5 and 6 mmol H+ equivalent per gram.
• the acid oligomerization catalyst, of the ion exchange resin type, used in step a) is a commercial acid resin sold under the reference TA801 by the company Axens.
• step a) is preferably carried out at a temperature between 20 and 300°C, preferably between 30 and 220°C, preferably between 40 and 200°C, and at a pressure preferably between 1.5 and 6.5 MPa, preferably between 2.0 and 4.0 MPa.
• the temperature at which step a) of oligomerization in the presence of silica-alumina is carried out preferably between 20 and 300°C, preferably between 30 and 220°C, preferably between 40 and 200°C, advantageously corresponds to the temperature at the inlet of step a), preferably at the inlet of the reactor implemented in step a).
• the oligomerization catalyst(s) based on silica alumina is(are) an amorphous catalyst(s) preferably consisting of an amorphous mineral material chosen from silica-aluminas and silica aluminas, and preferably among silica-aluminas.
• the SiCWAhOa mass ratio is between 0.1 and 10.
• the silica-alumina present in the oligomerization catalyst used in step a) oligomerization has the following characteristics:
• silica SiO2
• SiO2 silica
• a mass content of silica (SiO2) between 5% and 95% by weight, preferably between 10 and 80% by weight, more preferably between 20% and 80% by weight and even more preferably between 25% and 75% by weight, relative to the weight of the silica-alumina present in the oligomerization catalyst;
• a content of cationic impurities advantageously less than 0.1% by weight, preferably less than 0.05% by weight and even more preferably less than 0.025% by weight, relative to the weight of the silica-alumina present in the catalyst oligomerization, the content of cationic impurities being the total content of alkalis, in particular sodium.
• Catalysts as prepared as described in patent FR2926812 may be suitable as oligomerization catalyst for step a).
• the oligomerization catalyst used in step a) consists entirely of silica-alumina, that is to say it is devoid of any other element (i.e. i.e. it comprises less than 0.5% by weight, preferably less than 0.1% by weight of any element other than silica and alumina).
• the oligomerization catalyst used in step a) may contain at least one metallic element chosen from the metals of groups IVB, VB, VIB and VIII.
• the Group IVB metals titanium, zirconium and/or hafnium may be present in the oligomerization catalyst.
• the metals of group VB vanadium, niobium and/or tantalum may be present in the oligomerization catalyst.
• the metals of group VIB chromium, molybdenum and/or tungsten may be present in the oligomerization catalyst.
• the metals belonging to the first line of metals of group VIII namely iron, cobalt and nickel, are preferred.
• the content of these metals can be up to 10% by weight relative to the weight of the oligomerization catalyst.
• the oligomerization catalyst may optionally also contain silicon as a doping element deposited on the silica-alumina.
• step a) of oligomerization is carried out in the presence of a catalyst based on silica alumina at a temperature, advantageously at the inlet of step a), between 20°C and 300°C, preferably between 25 and 220°C, preferably between 30°C and 200°C, and at a pressure of between 1.5 and 6.5 MPa, preferably 2.0 to 4.0 MPa.
• step a) of oligomerization is preferably carried out in the presence of a silica-alumina catalyst, at a temperature, advantageously at the input of step a), preferably between 25 and 200°C, preferably between 30 and 190°C, and a pressure between 1.5 and 6.5 MPa, preferably between 2.0 and 4.0 MPa , to preferentially produce kerosene.
• a silica-alumina catalyst at a temperature, advantageously at the input of step a), preferably between 25 and 200°C, preferably between 30 and 190°C, and a pressure between 1.5 and 6.5 MPa, preferably between 2.0 and 4.0 MPa , to preferentially produce kerosene.
• step a) of oligomerization is preferably carried out in the presence of a silica-alumina catalyst, at a temperature , advantageously at the input of step a), preferably between 35 and 200°C, preferably between 40 and 190°C, and a pressure between 1.5 and 6.5 MPa, preferably between 2.0 and 4.0 MPa, to preferentially produce diesel.
• a silica-alumina catalyst at a temperature , advantageously at the input of step a), preferably between 35 and 200°C, preferably between 40 and 190°C, and a pressure between 1.5 and 6.5 MPa, preferably between 2.0 and 4.0 MPa, to preferentially produce diesel.
• the oligomerization catalyst(s) of step a) of oligomerization is in the form of spheres, pellets or extrudates, preferably extrudates.
• the oligomerization catalyst(s) is in the form of extrudates with a diameter of between 0.5 and 5 mm and more particularly between 0.7 and 2.5 mm.
• the shapes of the extrudates are cylindrical (which may or may not be hollow), twisted cylindrical, multilobed (2, 3, 4 or 5 lobes for example) or in the form of rings. Cylindrical and multilobed shapes are preferably used, but any other shape can be used.
• the oligomerization step is carried out in the presence of an oligomerization catalyst based on silica-alumina, preferably consisting of silica-alumina, which is present in the form of trilobed extrudates.
• an oligomerization catalyst based on silica-alumina preferably consisting of silica-alumina, which is present in the form of trilobed extrudates.
• the oligomerization step can use one or more reactors, preferably at least two, preferably at least three reactors, and up to ten, preferably six reactors, arranged in parallel or in series, preferably in series, comprising one or more different oligomerization catalysts, preferably comprising the same oligomerization catalyst.
• the operating conditions as well as the oligomerization catalysts described above can be applied to any of the reactors.
• the oligomerization step implements at least two or even at least three reactors in series.
• the oligomerization step can also use heat exchangers upstream of the reactor(s) to heat the olefinic feedstock.
• the oligomerization reaction is exothermic. At least part of the temperature increase linked to the exothermicity of the oligomerization reaction can be controlled by the first and second recycles (respectively comprising at least part of the light fraction corresponding at least in part to the non-load -converted and at least partly to the intermediate fraction), introduced in step a) of oligomerization.
• the exotherm can also be controlled at least in part by dilution of the olefinic charge by adding paraffins coming from a source external to the process, said paraffins being of the same molecular weight and/or heavier than the olefinic charge, said paraffins being aliphatic or cyclic, and/or by introducing an inert flow corresponding to a part of hydrogenated heavy fraction obtained at the end of step d), and in particular to a part of the kerosene cut and/or diesel fuel possibly separated in optional step e) or a mixture of kerosene and/or diesel cuts and residue from optional step e).
• the inert flow preferably represents between 0 and 6 times the fresh olefinic charge by weight, preferably between 0.5 to 4 by weight.
• the oligomerization step a) thus produces a reaction effluent which includes dimers, trimers and oligomers.
• This reaction effluent is sent in whole or in part to a fractionation step b).
• the process according to the invention comprises a step of fractionating the reaction effluent obtained at the end of step a), into at least:
• a heavy fraction comprising the oligomers present in the reaction effluent from step a), in particular olefinic compounds containing between 6 and 30, preferably between 9 and 25 carbon atoms, and more particularly between 9 and 16 carbon atoms in the case of kerosene or between 10 and 25 carbon atoms in the case of diesel.
• the light fraction comprises, preferably consisting of, at least a part, preferably all, of the olefinic feedstock not converted in step a). It therefore advantageously comprises C3 to C6 olefins, preferably C3 and/or C4, which have not been converted in step a).
• the light fraction may optionally also include compounds which do not react, that is to say which are not olefins, in particular paraffins in particular already present in the fresh olefinic feed.
• the quantity of this light fraction depends in particular on the conversion of the olefinic charge per pass of step a) of oligomerization.
• This fraction is advantageously recycled all or part in step a); it in fact constitutes at least part of the first recycle prepared in step c).
• part of this light fraction can be purged, continuously or discontinuously, in particular when the olefinic feed contains compounds which do not oligomerize, such as paraffins for example.
• the purged flow can be converted into liquefied petroleum gas or LPG (LPG or “liquified petroleum gas” according to Anglo-Saxon terminology) for example.
• the light fraction may comprise compounds 01 to 02, possibly generated during step a) and resulting from cracking and recombination reactions.
• a gaseous fraction can also be separated which includes compounds in 01 to C2, possibly generated during step a) and resulting from cracking and recombination reactions.
• the gaseous fraction possibly separated in step b) is preferably purged (i.e. removed from the process) continuously or discontinuously, for example to be recovered.
• the intermediate fraction comprises, preferably consisting of, at least a part, preferably all, of the dimers and trimers advantageously produced in step a).
• the products it contains, in particular the dimers and trimers, are too light to be converted into middle distillates, in particular into kerosene or diesel.
• the intermediate fraction can also optionally contain the unconverted 05 to 06 olefins if the olefinic feed contains 05 to 06 olefins.
• the intermediate fraction can also contain paraffins originating from the olefinic feed and boiling in the same ranges as the intermediate fraction.
• the intermediate fraction is free of paraffins, that is to say it comprises less than 0.5% by weight, preferably less than 0.1% by weight of paraffins relative to the total weight of the intermediate fraction.
• the intermediate fraction comprises 05+ olefin oligomers and preferably has a T95 lower than 140°C, in particular lower than 140°C in the case of kerosene production or preferably lower than 165°C. less than 170°C in the case of diesel production. She can therefore also be called C5-140°C or C5-165°C (preferably C5-170°C).
• at least part of the intermediate fraction can be recovered and removed from the process (that is to say purged) to be treated or directly recovered, in particular into gasoline.
• This possible purged part of the intermediate fraction can undergo a hydrogenation step, in particular can be sent to step d) of the process or to a hydrogenation step distinct from the process according to the invention and carried out for example under similar conditions to those described for step d), before being integrated into a gasoline pool.
• the heavy fraction advantageously comprises the oligomers present in the reaction effluent from step a).
• it comprises, in particular, olefinic compounds containing between 6 and 30, preferably between 9 and 25 carbon atoms.
• the heavy fraction has a T5 greater than or equal to 140°C, in particular greater than or equal to 140°C in the case of kerosene production or greater than or equal to 165°C, preferably greater than or equal to 170°C. C, in the case of diesel production.
• the heavy fraction is composed of C9+ olefin oligomers and very preferably boils between 140 and 300°C (also called 140-300°C fraction) or at a temperature greater than or equal to 165°C, preferably greater than or equal to 170°C.
• the heavy fraction can correspond to a kerosene fraction with a cut point making it possible to reach a flash point greater than or equal to 38°C.
• the heavy fraction can correspond to a diesel fraction with a cut point making it possible to reach a flash point greater than or equal to 55°C.
• fractionation step b) uses one or more distillation columns, preferably between one and three distillation columns.
• Recycling step c) of the process according to the invention comprises:
• all or part of the light fraction resulting from separation step b) constitutes the first recycle which is then recycled to step a) of oligomerization, preferably directly at the entrance to step a) and preferably upstream of the exchangers possibly implemented in step a) upstream of the reactors to heat the olefinic feedstock.
• the first recycle advantageously makes it possible to maximize the overall conversion and also to manage at least part of the exotherm of the oligomerization reaction in step a).
• the first recycle which corresponds to the part of the light fraction recycled to a), represents a quantity such that the weight ratio between the first recycle and the olefinic feedstock, which feed the oligomerization step a), is between 0.3 and 1.5, preferably between 0.5 and 1.2.
• all or part of the intermediate fraction resulting from separation step b) constitutes the second recycle which is then recycled to step a), preferably directly and in particular upstream of the exchangers possibly implemented upstream of the reactors in stage a).
• the intermediate fraction is not cooled before being transferred in whole or in part, as a second recycle, to step a) of oligomerization, which contributes in particular to the preheating of the olefinic feedstock at the input. of step a) by simple mixing.
• the second recycle which corresponds to the part of the intermediate fraction recycled to a), represents a quantity such that the weight ratio between the second recycle and the olefinic feedstock, which feed the oligomerization step a), is between 0.5 and 10.0, preferably between 1.0 and 5.0, preferably between 1.0 and 4.0.
• the heavy fraction comprising the oligomers and which results from fractionation step b) is not recycled, and in particular is not recycled to oligomerization step a).
• the heavy fraction comprises heavy olefinic compounds, in particular containing between 6 and 30, preferably between 9 and 25 carbon atoms.
• these compounds are known to have significant reactivity with respect to oligomerization.
• the process for preparing middle distillates according to the invention is therefore preferably devoid of recycling of the heavy fraction obtained in step b).
• the process advantageously does not require recycling of the heavy fraction whose T5 is greater than or equal to 140°C.
• the process advantageously does not require recycling of the heavy fraction whose T5 is greater than or equal to 165°C, preferably greater than or equal to 170°C.
• the olefinic filler is composed essentially of isobutene, preferably at least 90% by weight of isobutene and very advantageously less than 0.5% by weight, or even less than 0, 1% by weight of paraffins such as butane, relative to the total weight of the olefinic charge
• the oligomerization step a) is advantageously carried out in the presence of silica-alumina, preferably at a temperature between 20 and 100 °C, preferably between 30 and 90°C and very preferably between 35°C and 85°C, at a pressure preferably between 1.5 and 6.5 MPa, preferably between 2.0 and 4.0 MPa, and a VVH preferably between 0.20 and 0.30 h'1 , preferably between 0.20 and 0.25 h -1 .
• a flow of inerts (that is to say a flow of compounds inert to the oligomerization reaction, ie which do not react under the operating conditions of step a)), preferably composed of at least part of a portion of the hydrogenated heavy fraction obtained at the end of hydrogenation step d), is preferably used to feed step a) so as to control the exothermy of the oligomerization reaction and therefore reactivity.
• the intermediate fraction separated in step b) advantageously has a T95 lower than 140°C; the heavy fraction has a T5 greater than or equal to 140°C and preferably boils between 140 and 300°C.
• the second recycle prepared in step c) and which preferably consists of at least a part, preferably all, of the intermediate fraction separated in b), represents a quantity by weight such that the weight ratio between the second recycle and the olefinic feed at the input of step a) is between 1.0 and 5.0, preferably between 1.5 and 2.5, the second recycle being sent to step a ) oligomerization.
• the olefinic filler is composed essentially of propylene, preferably at least 90% by weight of propylene, optionally up to 10% by weight of butenes and very advantageously less than 0.5% weight, or even less than 0.1% by weight of paraffins, relative to the total weight of the olefinic charge
• the oligomerization step a) is advantageously carried out in the presence of silica-alumina, preferably at a temperature between 100 and 180°C, preferably between 110 and 170°C, preferably between 115 and 165°C, at a pressure preferably between 1.5 and 6.5 MPa, preferably between 2.0 and 4.0 MPa, and a VVH preferably between 0.20 and 0.30 h'1 , preferably between 0.20 and 0.25 h'1 .
• a flow of inerts (that is to say a flow of compounds inert to the oligomerization reaction, ie which do not react under the operating conditions of step a)) , preferably composed of at least part of a portion of the hydrogenated heavy fraction obtained at the end of hydrogenation step d), is preferably used to feed step a) so as to control the exothermy of the oligomerization reaction and therefore the reactivity.
• the intermediate fraction separated in step b) advantageously has a T95 lower than 140°C; the heavy fraction has a T5 greater than or equal to 140°C and preferably boils between 140 and 300°C.
• the second recycle prepared in step c) and which preferably consists of at least a part, preferably all, of the intermediate fraction separated in b), represents a quantity by weight such that the weight ratio between the second recycle and the olefinic feed at the input of step a) is between 1.0 and 5.0, preferably between 1.5 and 2.0, the second recycle being sent to step a ) oligomerization.
• the olefinic filler is composed essentially of n-butenes (but-1-enes and but-2-enes), preferably of at least 98% by weight of butenes and very advantageously less of 0.5% by weight of paraffins such as butane, relative to the total weight of the olefinic charge
• the oligomerization step a) is advantageously carried out in the presence of silica-alumina, preferably at a temperature between 130 and 200°C, preferably between 140 and 190°C, preferably between 145 and 185°C, at a pressure preferably between 1.5 and 6.5 MPa, preferably between 2.0 and 4.0 MPa, and a WH preferably between 0.20 and 0.30 h'1 , preferably between 0.20 and 0.25 h -1 .
• a flow of inerts (that is to say a flow of compounds inert to the oligomerization reaction, ie which do not react under the operating conditions of step a)), preferably composed at least in part of a portion of the hydrogenated heavy fraction obtained at the end of hydrogenation step d), can be used to feed step a) so as to control the exotherm of the reaction d oligomerization and therefore reactivity.
• the intermediate fraction separated in step b) advantageously has a T95 lower than 140°C; the heavy fraction has a T5 greater than or equal to 140°C and preferably boils between 140 and 300°C.
• the second recycle prepared in step c) and which preferably consists of at least a part, preferably all, of the intermediate fraction separated in b), represents a quantity by weight such that the weight ratio between the second recycle and the olefinic charge at the input of step a) is between 1.0 and 5.0, preferably between 3.5 and 4.0, the second recycle being sent to step a ) oligomerization.
• the olefinic filler is composed essentially of isobutene, preferably at least 90% by weight of isobutene and very advantageously less than 0.5% by weight, or even less than 0, 1% by weight of paraffins such as butane, relative to the total weight of the olefinic charge
• the oligomerization step a) is advantageously carried out in the presence of silica-alumina, preferably at a temperature between 30 and 100°C, preferably between 40 and 90°C, at a pressure preferably between 1.5 and 6.5 MPa, preferably between 2.0 and 4.0 MPa, and a WH preferably between 0.20 and 0.30 h -1 , preferably between 0.25 and 0.30 h'1 .
• an inert stream preferably composed of at least in part a portion of the heavy hydrogenated fraction obtained at the end of hydrogenation step d), is preferably used. to feed step a) so as to control the exotherm of the oligomerization reaction.
• the intermediate fraction separated in step b) advantageously has a T95 lower than 165°C; the heavy fraction has a T5 greater than or equal to 165°C.
• the second recycle which preferably consists of at least a part, preferably all, of the intermediate fraction separated in b), represents a weight quantity such that the weight ratio between the second recycle and the olefinic charge at the input to step a) is between 1.0 and 4.0, preferably between 1.0 and 2.0, the second recycle being sent to step a) of oligomerization.
• the olefinic filler is composed essentially of propylene, preferably at least 90% by weight of propylene, optionally up to 10% by weight of butenes and very advantageously less than 0.5% weight, or even less than 0.1% by weight of paraffins, relative to the total weight of the olefinic charge, and the oligomerization step a) is advantageously carried out in the presence of silica-alumina, preferably at a temperature between 110 and 180°C, preferably between 120 and 170°C, at a pressure preferably between 1.5 and 6.5 MPa, preferably between 2.0 and 4.0 MPa, and a WH preferably between 0.
• a flow of inerts preferably composed of at least in part a portion of the fraction heavy hydrogenated product obtained at the end of hydrogenation step d), is preferably used to feed step a) so as to control the exotherm of the oligomerization reaction.
• the intermediate fraction separated in step b) advantageously has a T95 lower than 165°C; the heavy fraction has a T5 greater than or equal to 165°C.
• the second recycle which preferably consists of at least a part, preferably all, of the intermediate fraction separated in b), represents a weight quantity such that the weight ratio between the second recycle and the olefinic charge at the input to step a) is between 1.0 and 4.0, preferably between 1.0 and 1.5, the second recycle being sent to step a) of oligomerization.
• the olefinic filler is composed essentially of n-butenes (but-1-enes and but-2-enes), preferably of at least 98% by weight of butenes and very advantageously less 0.5% by weight of paraffins such as butane, relative to the total weight of the olefinic charge
• the oligomerization step a) is advantageously carried out in the presence of silica-alumina, preferably at a temperature between 140 and 200°C, preferably between 145 and 190°C , at a pressure preferably between 1.5 and 6.5 MPa, preferably between 2.0 and 4.0 MPa, and a VVH preferably between 0.20 and 0.30 h' 1 , preferably between 0.
• an inert stream preferably composed of at least in part a portion of the heavy hydrogenated fraction obtained at the end of hydrogenation step d), is preferably used. to feed step a) so as to control the exotherm of the oligomerization reaction.
• the intermediate fraction separated in step b) advantageously has a T95 lower than 165°C; the heavy fraction has a T5 greater than or equal to 165°C.
• the second recycle which preferably consists of at least a part, preferably all, of the intermediate fraction separated in b), represents a weight quantity such as the weight ratio between the second recycle and the charge olefinic input to step a) is between 1.0 and 4.0, preferably between 3.0 and 3.5, the second recycle being sent to step a) of oligomerization.
• the temperature at which step a) of oligomerization in the presence of silica-alumina is implemented advantageously corresponds to the temperature at the inlet of step a), preferably in reactor inlet implemented in step a).
• the process according to the invention comprises a step of hydrogenating at least a part, preferably all, of the heavy fraction separated in step b) in the presence of hydrogen, to obtain a hydrogenated heavy fraction.
• the hydrogenation step makes it possible to saturate the olefinic bonds of at least part, preferably all, of the heavy fraction resulting from step c), in order to produce paraffins which can be incorporated directly into the fuel pools, notably the pool kerosene (or pool jet) and in a very particular way in the pool jet SPK (SPK for the Anglo-Saxon acronym for “Synthetic Paraffinic Kerosene”) which meets the specifications of standard ASTM D7566, Annex 5, or the gas oil pool and in a very particular manner in the gas oil pool which meets the specifications of European standard 15940.
• SPK synthetic Paraffinic Kerosene
• Step d) of hydrogenation of the unsaturated compounds makes it possible in particular to significantly improve the smoke point of the heavy fraction, and in particular of the middle distillates produced, and/or the elimination of possible sulfur and/or nitrogen impurities.
• step d) of hydrogenation is carried out in the presence of a catalyst preferably comprising at least one metal from group VIII, in particular nickel, palladium or platinum, deposited on an inert support, such as by example silica or alumina.
• the hydrogenation step is carried out in the presence of a catalyst based on palladium or nickel on an alumina support.
• any other catalyst making it possible to hydrogenate the product of the oligomerization step, and in particular the heavy fraction including C9+ olefins can be used.
• a catalyst chosen from NiMo, CoMo, NiCoMo on alumina type catalysts, and their mixtures can be used.
• Hydrogenation step d) is carried out, preferably in the liquid phase, advantageously at a pressure between 0.5 and 5.0 MPa, preferably between 1.0 and 5.0 MPa, and preferably at a temperature between 50 and 300°C, preferably between 60 and 200°C, in the presence of hydrogen preferably at a content between 0.5 and 3% by weight relative to the weight of the part of the heavy fraction feeding step d ).
• the hydrogenated heavy fraction comprises, preferably consists of, thus at least partly middle distillates, and more particularly a kerosene cut very advantageously meeting the kerosene specifications of the standards in force, in particular the kerosene specifications of the ASTM D7566 standard. , in particular of the ASTM D7566 Annex 5 standard, and/or a diesel cut meeting very advantageously the diesel specifications of the standards in force, in particular the diesel specifications of the European standard 15940.
• the hydrogenated heavy fraction obtained at the end of the step d) can possibly be sent in whole or in part to an optional separation step e).
• part of the heavy hydrogenated fraction obtained at the end of step d) is separated to constitute an inert flow which can then be recycled to step a) to help control the exotherm of the reaction oligomerization in step a), in parallel with the first recycle.
• the quantity by weight of the inert flow recycled to step a) represents 0 to 6 times, preferably 0.5 to 4 by weight of the weight of the fresh olefinic feedstock.
• the process according to the invention comprises a step of separating the heavy hydrogenated fraction, to obtain at least one middle distillate cut, in particular at least one kerosene cut and/or a gas oil fraction and optionally a gasoline fraction.
• a kerosene base is separated in step e) and this kerosene base preferably has a final evaporation temperature between 140 and 300°C and advantageously a flash point greater than or equal to 38°C;
• the separated diesel cut preferably has an evaporation temperature greater than or equal to 165°C, preferably greater than or equal to 170°C, and advantageously a flash point of at least 55°C.
• the optional separation step e) advantageously makes it possible to obtain:
• the optional separation step e) advantageously makes it possible to obtain:
• a head cut which corresponds to a gasoline advantageously comprising hydrocarbons having a number of carbon atoms of between 5 and 10;
• an intermediate cut advantageously comprising hydrocarbons having a number of carbon atoms of between 9 and 24, preferably between 9 and 16, and which constitutes a kerosene cut meeting commercial specifications
• the optional separation step e) advantageously makes it possible to obtain:
• kerosene cut whose lower (initial) distillation point is preferably at least 140°C and very preferably at least 150°C, and the final distillation point is less than or equal to 300°C, which constitutes a kerosene base meeting commercial specifications
• the optional separation step e) advantageously makes it possible to obtain:
• a head cut which corresponds to a gasoline advantageously comprising hydrocarbons having a number of carbon atoms of between 5 and 10;
• an intermediate cut advantageously comprising hydrocarbons having a number of carbon atoms of between 10 and 24, and which constitutes a diesel cut meeting commercial specifications.
• the process according to the invention thus makes it possible to improve the selectivity of a process for the oligomerization of light olefins towards middle distillates, in particular kerosene and/or diesel, and therefore to maximize the yields of middle distillates. , while having an optimal overall conversion of the olefin charge.
• the process according to the invention is a particularly flexible process since those skilled in the art can adapt the selectivity of the oligomerization and the separation of the effluents in order to maximize the production of kerosene and/or diesel, up to possibly producing only diesel or kerosene.
• Figure 1 schematically represents an implementation of the method according to the invention.
• a feedstock (1) rich in C3 and C4 olefins is treated in an oligomerization section (a).
• the reaction effluent 5 is sent to a separation step (b) and separated in a series of columns to produce:
• Stream 4 is at least partly recycled at the oligomerization inlet (a). Part of the flow (4) can be purged or recovered in another unit (flow 6), either continuously or from time to time, depending on the nature of the load.
• Stream 3 is sent to the oligomerization step, at least in part, preferably in full, at the oligomerization inlet (a). Part of stream 3 can also be sent for recovery in a gasoline pool (stream 8). Stream 8 can possibly be sent to hydrogenation c) to then be upgraded with stream 11.
• Stream 9 is sent to a hydrogenation section (c).
• the hydrogenated effluent 10 is then separated in a section (d), into:
• An optional stream 2 constituted for example from a kerosene + diesel mixture (stream 12) is sent to step a) of oligomerization. It corresponds to an inert flow used to control the exothermicity of the reaction in the reactors of the oligomerization section a).
• a C4 olefinic hydrocarbon feedstock comprising 24.8% by weight of 1-butene, 75% by weight of 2-butenes and 0.2% by weight of n-butane, is oligomerized according to the embodiment of the process described in Figure 1, in the presence of a silica-alumina catalyst (commercial IP 811 catalyst from Axens), at a temperature between 140 and 190° C., a pressure of 3.5 MPa and at a WH of 0.3 h' 1 .
• the oligomerization reaction is carried out in 3 reactors in series, with an intermediate exchanger between each reactor, allowing cooling before entering the next reactor.
• reaction effluent obtained at the end of the oligomerization step is separated by distillation into three cuts:
• the conversion of the olefinic feedstock is greater than or equal to 90% by weight.
• Hydrogenation is carried out in the presence of a nickel catalyst on an alumina support, at 180°C under 3.0 MPa of hydrogen with a WH of 0.5 h -1 and a hydrogen flow rate of 50 NL/h.
• the rate of olefins observed after hydrogenation is very low (bromine number ⁇ 0.8 g/100g), i.e. a high hydrogenation rate (greater than 99%).
• the hydrogenation effluent is then sent to a distillation section where it is separated into three cuts:
• a biosourced C4 olefinic hydrocarbon feedstock (from the dehydration of isobutanol obtained by fermentation of sugars), comprising 94.5% by weight of isobutene and
• reaction effluent obtained at the end of the oligomerization step is separated by distillation into four cuts:
• the conversion of the olefinic feedstock is greater than or equal to 90% by weight.
• the hydrogenation of the 140-300°C cut is carried out in the presence of a nickel catalyst on an alumina support, at 180°C under 3.0 MPa of hydrogen with a WH of 0.5 h -1 and a hydrogen flow rate of 50 NL/h.
• the rate of olefins observed after hydrogenation is very low (bromine number ⁇ 0.8 g/100g), i.e. a high hydrogenation rate (greater than 99%).
• the hydrogenation effluent is then sent to a distillation section where it is separated into three cuts:
• a C4 olefinic hydrocarbon feedstock similar to that treated by the process described in Example 1 is treated in Example 3: it comprises 24.8% by weight of 1-butene, 75% by weight of 2-butenes and 0.2 % weight of n-butane.
• the C4 olefinic hydrocarbon feedstock is oligomerized under operating conditions similar to those of the process described in Example 1. However, the C5-140°C cut of the reaction effluent is not recycled at the entrance to the oligomerization stage.
• reaction effluent obtained at the end of the oligomerization step is separated by distillation into three cuts:
• Hydrogenation is carried out under the same conditions as Example 1.
• the hydrogenation effluent is then sent to a distillation section where it is separated into three cuts:

Landscapes

• Chemical & Material Sciences (AREA)
• Oil, Petroleum & Natural Gas (AREA)
• Organic Chemistry (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Engineering & Computer Science (AREA)
• General Chemical & Material Sciences (AREA)
• Water Supply & Treatment (AREA)
• Analytical Chemistry (AREA)
• Crystallography & Structural Chemistry (AREA)
• Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
• Production Of Liquid Hydrocarbon Mixture For Refining Petroleum (AREA)
• Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)
• Catalysts (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=82594853

Family Applications (1)

Country Status (10)

Citations (1)

Family Cites Families (12)

• 2022
  • 2022-04-05 FR FR2203112A patent/FR3134110B1/fr active Active
• 2023
  • 2023-03-31 TW TW112112528A patent/TW202407085A/zh unknown
  • 2023-04-03 AR ARP230100829A patent/AR128982A1/es unknown
  • 2023-04-04 JP JP2024558987A patent/JP2025511370A/ja active Pending
  • 2023-04-04 US US18/854,277 patent/US20250243133A1/en active Pending
  • 2023-04-04 CA CA3245471A patent/CA3245471A1/fr active Pending
  • 2023-04-04 WO PCT/EP2023/058741 patent/WO2023194337A1/fr not_active Ceased
  • 2023-04-04 EP EP23717472.7A patent/EP4504870A1/de active Pending
  • 2023-04-04 KR KR1020247034775A patent/KR20240170924A/ko active Pending
  • 2023-04-04 AU AU2023251159A patent/AU2023251159A1/en active Pending

Patent Citations (1)

Also Published As

Similar Documents

Legal Events