METHOD FOR PROCESSING A TIRE PYROLYSIS OIL

Abstract

The present invention relates to a process for treating a feed comprising at least 5% by weight of a tire pyrolysis oil relative to the total weight of the feed, said tire pyrolysis oil having a sulfur content of between 2000 and 10000 ppm by weight relative to the total weight of the oil, comprising: a) an optional selective hydrogenation step, b) a hydrogenation step in the presence of hydrogen and a catalyst to obtain a hydrogenated effluent, c) a hydrotreating step of said hydrogenated effluent in the presence of hydrogen and a catalyst to obtain a hydrotreated effluent, d) a separation step, carried out between steps b) and c) and / or after step c), said step being fed by the hydrogenated effluent from step b) and / or by the hydrotreated effluent from step c), and an aqueous solution, to obtain at least a gaseous effluent, an aqueous effluent and a hydrocarbon effluent.

Description

Title of the invention: METHOD FOR TREATMENT OF A TIRE PYROLYSIS OIL technical field

[0001] The present invention relates to the field of tire recycling. More particularly, the present invention concerns a process for treating a feedstock comprising pyrolysis oil, of which at least 5% by weight is derived from tires. Tire pyrolysis oils generally contain a high sulfur content. The process makes it possible to eliminate, at least partially, the impurities that said feedstock may contain in relatively large quantities, while reducing, by using a pyrolysis oil with a high sulfur content, the consumption of sulfurizing agent required to maintain the catalysts in sulfide form during the catalytic stages of the process. Previous technique

[0002] Plastics from collection and sorting streams, recycled tires, or solid recovered fuels (SRF) can undergo a pyrolysis step to recover their value. Pyrolysis consists of heating, with or without a catalyst, a feed containing plastic and / or recycled tires and / or SRF in the absence of oxygen, leading to the formation of three main products: a liquid hydrocarbon phase at room temperature, also called pyrolysis oil; a light gas phase, also called pyrolysis gas; and a solid residue, also called char in Anglo-Saxon terminology.

[0003] The liquid hydrocarbon phase, pyrolysis oil, can be used in a fuel storage unit for gasoline, kerosene or diesel.

[0004] Another way of valorizing pyrolysis oils is the use of these pyrolysis oils as a feed in a steam cracking unit in order to (re)create olefins, the latter being monomers constituting certain polymers.

[0005] However, pyrolysis oils often contain high levels of impurities that are incompatible with direct storage in a fuel storage unit or with steam cracking units or units located downstream of steam cracking units, particularly polymerization and selective hydrogenation processes. These impurities can generate operability problems, including corrosion (especially due to the presence of chlorine), coking, catalytic deactivation, and incompatibility issues with the target polymers. The presence of diolefins can also lead to pyrolysis oil instability problems characterized by the formation of Gums. Gums and insolubles that may be present in pyrolysis oil can cause clogging problems in the processes.

[0006] One way to remove these impurities contained in pyrolysis oils is to carry out hydrotreatment (HDT) in the presence of catalysts. Such processes are described, for example, in WO2018 / 055555, WO2021 / 165178 or WO2022 / 144235.

[0007] Application WO2022 / 144235 describes a process for treating plastic pyrolysis oil to reduce and / or eliminate impurities contained in the pyrolysis oil in order to obtain an effluent suitable for a steam cracker. The process comprises the following steps:

[0008] a) hydrogenation of said feed in the presence of at least hydrogen and at least one hydrogenation catalyst at an average temperature between 140 and 340°C, the temperature at the outlet of step a) is at least 15°C higher than the temperature at the inlet of step a), to obtain a hydrogenated effluent; b) hydrotreating said hydrogenated effluent in the presence of at least hydrogen and at least one hydrotreating catalyst, to obtain a hydrotreated effluent, the average temperature of step b) being higher than the average temperature of step a); c) separation of the hydrotreated effluent in the presence of an aqueous stream, at a temperature between 50 and 370°C, to obtain at least a gaseous effluent, an aqueous liquid effluent and a hydrocarbon liquid effluent.

[0009] One way to eliminate impurities contained in pyrolysis oils is to carry out hydrotreatment in the presence of catalysts which are active in the form of sulfides.

[0010] In the context of feedstocks containing plastic pyrolysis oil, the feedstocks are generally quite low in sulfur. However, a minimum ppH2S is necessary in the hydrotreating reactor to maintain the catalysts in sulfide form and thus prevent their reduction. To maintain a sufficient ppH2S in the reactor, and given that ex-plastic feedstocks do not contain enough sulfur, a sulfurizing agent is generally, or even necessarily, added continuously, typically DMDS (dimethyl disulfide), to the feedstock. The sulfurizing agent decomposes very rapidly into H2S through the action of temperature and hydrogen at the reactor inlet and therefore provides the quantity of H2S necessary to ensure a minimum and sufficient ppH2S.

[0011] The levels of sulfur, oxygen, and / or nitrogen compounds often depend on the origin of the pyrolysis oil. Thus, pyrolysis oils from tires generally contain more heteroatoms than pyrolysis oils from plastics and / or RDF, particularly sulfur compounds.

[0012] The process according to the invention notably takes advantage of the significant quantity of sulfur impurities contained in tire pyrolysis oil by using these impurities as a sulfurizing agent to maintain the catalysts in sulfide form during the catalytic steps of the process. Using tire pyrolysis oil thus allows for a significant reduction in the consumption of sulfurizing agents that would normally be added, generally of the DMDS type. Summary of the invention

[0013] More specifically, the invention relates to a process for treating a feed comprising at least 5% by weight of a tire pyrolysis oil relative to the total weight of the feed, said tire pyrolysis oil having a sulfur content of between 2000 and 15000 ppm by weight relative to the total weight of the tire pyrolysis oil, said process comprising the following steps:

[0014] a) optionally a selective hydrogenation step implemented in a reaction section implementing at least one fixed-bed reactor having n catalytic beds, n being an integer greater than or equal to 1, each comprising at least one selective hydrogenation catalyst, said selective hydrogenation reaction section being fed at least by said feed and a gaseous stream comprising hydrogen, in the presence of at least one selective hydrogenation catalyst, at an average temperature between 100 and 280°C, a partial pressure of hydrogen between 1.0 and 10.0 MPa abs. and an hourly volumetric velocity between 0.1 and 10.0 h1, to obtain a selectively hydrogenated effluent;

[0015] b) a hydrogenation step carried out in a hydrogenation reaction section, employing at least one fixed-bed reactor having n catalytic beds, n being an integer greater than or equal to 1, each comprising at least one hydrogenation catalyst, said hydrogenation reaction section being fed at least by said feedstock or said selectively hydrogenated effluent from step a) and a gas stream comprising hydrogen, said hydrogenation reaction section being carried out at an average temperature between 140 and 400°C, a partial pressure of hydrogen between 1.0 and 10.0 MPa abs. and an hourly volumetric velocity between 0.1 and 10.0 h1, to obtain a hydrogenated effluent,

[0016] c) a hydrotreating step implemented in a hydrotreating reaction section, employing at least one fixed-bed reactor having n catalytic beds, n being an integer greater than or equal to 1, each comprising at least one hydrotreating catalyst, said hydrotreating reaction section being fed at least by said hydrocarbon effluent from step d) when separation step d) is carried out between steps b) and c), and / or at least by the hydrogenated effluent from step b) when separation step d) is carried out after step (c) and a gaseous stream comprising hydrogen, said hydrotreating reaction section being operated at an average temperature between 250 and 430°C, a partial pressure of hydrogen between 1.0 and 10.0 MPa abs. and an hourly volumetric velocity between 0.1 and 10.0 h1, to obtain a hydrotreated effluent,

[0017] d) a separation step, carried out between steps b) and c) and / or after step c), said step being fed with the hydrogenated effluent from step b) when separation step d) is carried out between steps b) and c), and / or with the hydrotreated effluent from step c) when separation step d) is carried out after step c), and an aqueous solution, said step being carried out in a separation section, to obtain at least one gaseous effluent, one aqueous effluent and one hydrocarbon effluent.

[0018] The present invention therefore relates to a process for purifying an oil from the pyrolysis of tires, possibly supplemented with pyrolysis oil from plastics and / or RDF, of at least part of its impurities, which allows it to be hydrogenated and thus to be able to be valorized in particular by incorporating it directly into the fuel storage unit or by making it compatible with treatment in a steam cracking unit while being able to considerably reduce the consumption of the sulfurizing agent.

[0019] Another advantage of the invention is that it prevents the risks of clogging and / or corrosion of the treatment unit in which the process of the invention is implemented, risks exacerbated by the presence, often in significant quantities, of diolefins, metals, and halogenated compounds in pyrolysis oil. These risks of clogging and / or corrosion are notably reduced by a separation step involving washing with an aqueous solution.This washing / separation step makes it possible, in particular, to remove ammonium chloride salts, which are formed by the reaction between chloride ions, released by the hydrogenation of chlorinated compounds in the form of HCl, notably during the hydrogenation step followed by dissolution in water, and ammonium ions, generated by the hydrogenation of nitrogen compounds in the form of NH3 during the hydrotreatment step and / or introduced by the injection of an amine when the content of chlorinated compounds is high, followed by dissolution in water. The high content of nitrogen compounds in tire pyrolysis oil makes it possible to reduce, or even eliminate, the need to add a nitrogen compound, which presents another advantage of the invention.

[0020] The process of the invention thus makes it possible to obtain a hydrocarbon effluent from a tire pyrolysis oil that is at least partially free of impurities from the starting tire pyrolysis oil, thereby limiting operability problems, such as corrosion, coking or catalytic deactivation problems, which can be caused by these impurities, particularly in steam cracking units and / or in units located downstream of steam cracking units.

[0021] According to one variant, the charge comprises a plastics pyrolysis oil and / or solid recovered fuels.

[0022] According to one variant, the charge consists of tire pyrolysis oil and plastic pyrolysis oil(s) and / or solid recovered fuels.

[0023] According to one variant, the charge comprises a pyrolysis oil from tyres in a content of between 5 and 99% by weight and a pyrolysis oil from plastics and / or CSR in a content of between 1 and 95% by weight relative to the total weight of the charge.

[0024] According to one variant, separation step d) comprises the following steps: dl) a separation step, fed by the hydrogenated effluent from step b) when separation step d) is carried out between steps b) and c), and / or by the hydrotreated effluent from step c) when separation step d) is carried out after step c), said step being carried out at a temperature above the precipitation temperature of ammonium halides and at a pressure substantially identical to the pressure of step b) to obtain at least a first gaseous effluent and a liquid effluent, part of which may be recycled, as recycled effluent, upstream of step b),

[0025] d2) a separation stage, fed by the first gaseous effluent and even at least a portion of the liquid effluent from step dl), and an aqueous solution, said step being carried out at a temperature lower than the precipitation temperature of ammonium halides and at a pressure substantially the same as or lower than the pressure of step b), to obtain at least a second gaseous effluent, an aqueous effluent and a hydrocarbon effluent.

[0026] According to one variant, step d1) is carried out at a temperature between 200 and 450°C and step d2) is carried out at a temperature greater than or equal to 20°C and less than 200°C.

[0027] According to one variant, said process includes at least one pretreatment step of the feed comprising a tire pyrolysis oil, said pretreatment step being carried out upstream of step a) and / or upstream of step b) and includes an adsorption step and / or a filtration step and / or a centrifugation step and / or a decantation step and / or an electrostatic separation step and / or a washing step using an aqueous solution and / or a gas stripping step.

[0028] According to one variant, said process includes a step e) of fractionating all or part of the hydrocarbon effluent from step d) when separation step d) is carried out after step c), and / or of all or part of the hydrotreated effluent from step c) when separation step d) is carried out between steps b) and c), to obtain at least one gas stream, one naphtha cut and at least one middle distillates cut.

[0029] According to one variant, said process comprises a step f) of hydrocracking put into work in a hydrocracking reaction section, employing at least one fixed-bed reactor having n catalytic beds, n being an integer greater than or equal to 1, each comprising at least one hydrocracking catalyst, said hydrocracking reaction section being fed by at least a portion of said hydrocarbon effluent from step d) when separation step d) is carried out after step c), and / or by at least a portion of the hydrotreated effluent from step c) when separation step d) is carried out between steps b) and c), and / or by at least a portion of the middle distillate cut from fractionation step e) and a gas stream comprising hydrogen, said hydrocracking reaction section being operated at an average temperature between 250 and 450°C, a partial pressure of hydrogen between 1.5 and 20.0 MPa abs.and an hourly volumetric velocity between 0.1 and 10.0 h⁻¹ to obtain a first hydrocracked effluent.

[0030] According to one variant, said hydrogenation catalyst of step b) comprises a support selected from alumina, silica, silica-aluminas, magnesia, clays and mixtures thereof and a hydro-dehydrogenating function comprising either at least one element from group VIII and at least one element from group VIB, or at least one element from group VIII.

[0031] According to one variant, said hydrotreating catalyst of step c) comprises a support selected from alumina, silica, silica-aluminas, magnesia, clays and mixtures thereof, and a hydro-dehydrogenating function comprising at least one element from group VIII and / or at least one element from group VIB.

[0032] According to one variant, at least part of the hydrocarbon effluent from step d) when separation step d) is carried out after step c), and / or at least part of the hydrotreated effluent from step c) when separation step d) is carried out between steps b) and c) and / or at least one of the cuts from fractionation step e) is sent to steam cracking step g) carried out in at least one pyrolysis furnace at a temperature between 700 and 900°C and at a pressure between 0.05 and 0.3 MPa relative.

[0033] According to one variant, the process includes step a) of selective hydrogenation.

[0034] According to one variant, said selective hydrogenation catalyst of step a) comprises a support selected from alumina, silica, silica-aluminas, magnesia, clays and mixtures thereof, and a hydro-dehydrogenating function comprising at least one element from group VIII and / or at least one element from group VIB.

[0035] The present invention also relates to the product obtained by the process according to the invention.

[0036] According to one variant, the product comprises, in relation to the total weight of the product: - a total metallic content of less than or equal to 10.0 ppm by weight, - including an iron content of less than or equal to 200 ppb by weight, and / or - a silicon content less than or equal to 5.0 ppm by weight, and / or - a sulfur content less than or equal to 100 ppm by weight, and / or - a nitrogen content less than or equal to 100 ppm by weight, and / or - a chlorine content less than or equal to 10 ppm by weight, and / or - a mercury content less than or equal to 5 ppb by weight.

[0037] According to one variant, the product has a biological carbon content according to ASTM D6866 of between 1 and 70% by weight.

[0038] According to the present invention, 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 were not the case and the limit values ​​were not included in the range described, such clarification will be provided by the present invention.

[0039] In this description, the term "include" is synonymous with (means the same as) "include" and "contain," and is inclusive or open and does not exclude other elements not mentioned. It is understood that the term "include" includes the exclusive and closed term "consist."

[0040] In the sense of the present invention, the different parameter ranges for a given step, such as pressure ranges and temperature ranges, can be used alone or in combination. For example, in the sense of the present invention, a range of preferred pressure values ​​can be combined with a range of preferred temperature values.

[0041] According to the present invention, the pressures are absolute pressures, also noted as abs., and are given in absolute MPa (or abs. MPa), unless otherwise indicated.

[0042] In the following, particular and / or preferred embodiments of the invention may be described. They may be implemented separately or in combination with each other, without limitation of combination where technically feasible.

[0043] In the following, the groups of chemical elements are given according to the CAS classification (CRC Handbook of Chemistry and Physics, publisher CRC Press, editor-in-chief DR Lide, 81st edition, 2000-2001). For example, group VIII (or VIIIB) according to the CAS classification corresponds to the metals in columns 8, 9 and 10 according to the new IUP AC classification.

[0044] The metal content is measured by X-ray fluorescence. DETAILED DESCRIPTION The charge

[0045] According to the invention, the charge comprises at least 5% by weight of a tire pyrolysis oil having a sulfur content between 2000 and 15000 ppm by weight relative to the total weight of the tire pyrolysis oil.

[0046] The charge may also include any other pyrolysis oil, including plastic pyrolysis oil and / or solid recovered fuels (SRF).

[0047] In addition, the feed can optionally be supplemented with a conventional petroleum feed and / or a feed from biomass conversion.

[0048] In the following text, "pyrolysis oil" means an oil obtained from the pyrolysis of plastics and / or tires and / or RDF, unless otherwise specified. When the origin of the pyrolysis oil is important, its source is added (for example, tire pyrolysis oil).

[0049] Tires are mainly made of rubber for their elastic properties (mixture of elastomers of the natural and synthetic cross-linked type, with added additives of the type silica, resin, sulfur, zinc oxide, carbon black, etc.) and textile and metallic fibers for their reinforcing properties.

[0050] As for plastic waste, it is generally a mixture of several polymers. It may include, alone or in mixtures, polyethylene (low and / or high density), polypropylene, polyethylene terephthalate, polyvinyl chloride, and polystyrene. Furthermore, depending on its use, plastics may contain, in addition to polymers, other compounds such as plasticizers, pigments, dyes, or residues of polymerization catalysts. Plastic waste may also contain, in small quantities, biomass originating, for example, from household waste.

[0051] Solid recovered fuels (SRF), also called refuse derived fuel (RDF) or solid recovered fuels (SRF) in English, are non-hazardous solid wastes prepared for energy recovery, whether they originate from household and similar waste, waste from economic activities, or construction and demolition waste. SRF is generally a mixture of any combustible waste such as used tires, food by-products (fats, animal meal, etc.), viscose and wood waste, light fractions from shredders (e.g., end-of-life vehicles, waste electrical and electronic equipment (WEEE)), household and commercial waste, and residues from the recycling of various types of waste, including certain municipal waste, plastic, textile, and wood waste, among others. SRF generally contains plastic waste.

[0052] The pyrolysis oil included in the feed, whether it comes from tires, plastics and / or RDF, comes from a pyrolysis step of a feed containing tires, plastic(s) and / or RDF in a pyrolysis unit.

[0053] The pyrolysis step can be carried out by a thermal pyrolysis treatment, catalytic or even be prepared by hydropyrolysis (pyrolysis in the presence of a catalyst and hydrogen).

[0054] The pyrolysis step is generally carried out at a temperature between 250°C and 750°C. The pyrolysis step can be carried out under more or less severe conditions.

[0055] The low-severity pyrolysis step is carried out at a temperature between 250°C and 450°C, preferably between 275°C and 425°C, and particularly preferably between 300°C and 400°C. The low-severity pyrolysis step produces pyrolysis oils rich in mono- and diolefins as well as a significant amount of aromatics, which may include chlorinated compounds.

[0056] The high-severity pyrolysis step is carried out at a temperature between 450°C and 750°C, preferably between 500°C and 700°C, and particularly preferably between 550°C and 650°C. The high-severity pyrolysis step produces pyrolysis oils rich in aromatics, which may include chlorinated compounds.

[0057] The pyrolysis unit may include one or more reactors configured to convert the feed into gaseous and liquid-phase products (for example, simultaneously). The reactor(s) may contain one or more beds of inert materials or pyrolysis catalysts, including sand, zeolite, or combinations thereof. Generally, the pyrolysis catalyst is capable of transferring heat to the components undergoing the pyrolysis process in the pyrolysis unit.

[0058] The pyrolysis unit may include one or more pieces of equipment, for example one or more heated extruders, a heated rotary kiln, heated tank-type reactors, empty heated containers, closed heated surfaces where the charge flows along the wall, containers surrounded by furnaces or ovens or other equipment providing a heated surface.

[0059] In one or more embodiments of the pyrolysis unit, a purge gas is used in all or part of the pyrolysis stage(s) to enhance the cracking of plastics and / or tires and / or RDF, produce valuable products, provide a feed for steam cracking, or combinations thereof. The purge gas may comprise hydrogen (H2), nitrogen (N2), steam, produced gases, or combinations thereof.

[0060] Pyrolysis oil, whether derived from tires, plastics, and / or RDF, generally has a boiling point range of 40°C to 1000°C, preferably between 45°C and 650°C. Tire pyrolysis oil generally has a boiling point range of 100°C to 1000°C, preferably between 150°C and 650°C. Plastic pyrolysis oil, which is generally lighter in concentration, generally has a boiling point range of 40°C to 700°C, preferably between 45°C and 550°C.

[0061] It is also possible to use only a part of the pyrolysis oil obtained by pyrolysis, for example a pyrolysis oil which has been topped and / or tailed beforehand by a pre-fractionation step.

[0062] The density of pyrolysis oil, whether derived from tires, plastics, and / or RDF, generally has a density, measured at 15°C according to the ASTM D4052 method, of between 0.75 and 1.05 g / cm³, preferably between 0.75 and 0.95 g / cm³. The density of tire pyrolysis oil, measured at 15°C according to the ASTM D4052 method, is generally between 0.75 g / cm³ and 1.05 g / cm³, preferably between 0.80 g / cm³ and 0.98 g / cm³. The density of the pyrolysis oil of plastics and / or RDF, measured at 15°C according to the ASTM D4052 method, is generally lower and is usually between 0.75 and 0.99 g / cm3, preferably between 0.75 and 0.95 g / cm3.

[0063] Pyrolysis oil, whether derived from tires, plastics, and / or RDF, is advantageously in liquid form at ambient temperature and comprises, in particular, a mixture of hydrocarbon compounds, notably paraffins (n- and i-paraffins), olefins (mono- and / or diolefins), naphthenes, and aromatics. In particular, depending on the origin of the feedstock processed by the pyrolysis unit, the pyrolysis oil may comprise up to 70% by weight of paraffins, up to 90% by weight of naphthenes, up to 90% by weight of olefins, and up to 90% by weight of aromatics, it being understood that the sum of the paraffins, naphthenes, olefins, and aromatics is equal to 100% by weight of the hydrocarbon compounds.

[0064] Tyre pyrolysis oil generally contains a significant amount of aromatic compounds, for example an aromatic compound content greater than 30% wt, preferably greater than 40% wt, and particularly preferably greater than 50% wt relative to the weight of the tyre pyrolysis oil.

[0065] Pyrolysis oil, whether derived from tires, plastics, and / or RDF, may contain diolefins. The diolefin content is commonly determined indirectly as the maleic anhydride value (MAV). The method is based on the Diels-Aider addition reaction between conjugated diolefins and maleic anhydride. The method for determining the MAV is described in C. López-Garcla et al., Near Infrared Monitoring of Low Conjugated Diolefins Content in Hydrotreated FCC Gasoline Streams, Oil & Gas Science and Technology - Rev. IFP, Vol. 62 (2007), No. 1, pp. 57-68. The MAV is expressed as mg of maleic anhydride reacted with 1 g of sample (mg / g). MAV preferably varies between 5 and 100 mg / g in pyrolysis oils.

[0066] Pyrolysis oil, whether derived from tires, plastics and / or RDF, may contain some compounds of biological origin, such as an oil Pyrolysis oil from tires produced from natural rubber elastomers, or pyrolysis oil from plastics and / or RDF produced from plastic waste and / or RDF, which may contain, in small quantities, biomass from sources such as municipal solid waste. The biocarbon content (according to the C14 radiocarbon analytical method according to ASTM D6866) may be between 0 and 70% by weight, preferably between 0.1 and 60% by weight relative to the total weight of the pyrolysis oil. In the case of pyrolysis oil from tires, the biocarbon content (according to the C14 radiocarbon analytical method according to ASTM D6866) may be between 20 and 70% by weight, preferably between 30 and 60% by weight relative to the total weight of the pyrolysis oil. This allows a biological composition to be incorporated into the products of the process according to the invention.

[0067] The impurity content in pyrolysis oils often depends on the oil's origin. Thus, pyrolysis oils from tires generally contain more heteroatoms than pyrolysis oils from plastics and / or RDF, particularly sulfur compounds, but also nitrogenous, oxygenated, and halogenated compounds (especially chlorinated compounds). They also generally contain more metals (especially silicon).

[0068] Pyrolysis oil, whether derived from tires, plastics, and / or RDF, may include, and most often does include, impurities such as metals, particularly iron and silicon, and halogenated compounds, particularly chlorinated compounds. These impurities may be present at high levels, for example up to 500 ppm by weight, or even 700 ppm by weight, or even 1000 ppm by weight, and even 5000 ppm by weight, of halogenated elements (particularly chlorine, but also bromine, fluorine, or iodine) supplied by halogenated compounds, and generally between 1 and 1000 ppm by weight, or between 1 and 700 ppm by weight, or between 1 and 500 ppm by weight of halogenated elements. Pyrolysis oil can contain up to 500 ppm by weight or even 700 ppm by weight or even 1000 ppm by weight and even 5000 ppm by weight of chlorine element supplied by chlorinated compounds, and generally between 1 and 1000 ppm by weight or between 1 and 700 ppm by weight or between 1 and 500 ppm by weight of chlorine element.Pyrolysis oil can contain up to 50 ppm by weight or even 100 ppm by weight of bromine from brominated compounds, and generally between 1 and 100 ppm by weight or between 1 and 50 ppm by weight of bromine.

[0069] Pyrolysis oil, whether derived from tires, plastics, and / or RDF, may contain up to 200 ppm by weight, or even 1500 ppm by weight, of metallic or semi-metallic elements, and generally between 1 and 1500 ppm by weight or between 1 and 200 ppm by weight of metallic or semi-metallic elements. Alkali metals, alkaline earth metals, transition metals, post-transition metals, and metalloids may be These contaminants are considered metallic, referred to as metals or metallic or semi-metallic elements. Specifically, metals or metallic or semi-metallic elements include silicon, iron, or both. Pyrolysis oil may contain up to 200 ppm by weight or 1000 ppm by weight of silicon, and typically between 1 and 1000 ppm by weight, or between 1 and 500 ppm by weight, or between 1 and 200 ppm by weight of silicon. Pyrolysis oil may also contain up to 50 ppm by weight or 100 ppm by weight of iron, and typically between 1 and 100 ppm by weight, or between 1 and 50 ppm by weight of iron. Pyrolysis oil may also contain phosphorus, sodium, calcium, potassium, and magnesium.

[0070] Pyrolysis oil, whether derived from tires, plastics and / or RDF, may also include other impurities such as heteroelements supplied in particular by sulfur compounds, oxygenated compounds and / or nitrogenous compounds, at levels generally less than 40,000 ppm weight of heteroelements and preferably less than 15,500 ppm weight of heteroelements, and generally between 1 and 40,000 ppm weight or between 1 and 15,500 ppm weight of heteroelements.

[0071] Oxygenated compounds are generally present in a content of less than 15000 ppm by weight and preferably less than 10000 ppm by weight, and generally between 1 and 15000 ppm by weight or between 1 and 10000 ppm by weight of oxygen.

[0072] Nitrogen compounds are generally present in a concentration of less than 10,000 ppm by weight and preferably less than 8,000 ppm by weight, and generally between 1 and 10,000 ppm by weight or between 1 and 8,000 ppm by weight of nitrogen. Tire pyrolysis oils are generally more heavily loaded with nitrogen compounds than plastic and / or RDF pyrolysis oils. The nitrogen compounds present in a tire pyrolysis oil are generally present in a concentration of less than 10,000 ppm by weight and preferably less than 8,000 ppm by weight, and generally between 2,000 and 10,000 ppm by weight or between 2,500 and 8,000 ppm by weight of nitrogen compounds.

[0073] The nitrogen compounds present in a plastics pyrolysis oil are generally present in a content of less than 5000 ppm by weight and preferably less than 2500 ppm by weight, and generally between 5 and 5000 ppm by weight or between 10 and 2500 ppm by weight of nitrogen compounds.

[0074] The sulfur content varies greatly depending on the origin of the pyrolysis oil.

[0075] The sulfur compounds present in a tire pyrolysis oil are generally present in a content of less than 15000 ppm by weight and preferably less than 10000 ppm by weight, and generally between 2000 and 15000 ppm by weight or between 2500 and 12000 ppm by weight of sulfur compounds, preferably between 3000 and 11000 ppm by weight of sulfur compounds.

[0076] Sulfur compounds present in a plastic pyrolysis oil are gen- rarely present in a content of less than 2000 ppm by weight and preferably less than 500 ppm by weight, and generally between 5 and 2000 ppm by weight or between 10 and 500 ppm by weight of sulfur compounds.

[0077] Pyrolysis oil, whether derived from tires, plastics and / or RDF, may also include other impurities such as heavy metals like mercury, arsenic, zinc and lead, for example up to 500 ppb weight of mercury or arsenic, and generally between 1 and 300 ppb weight or between 1 and 200 ppb weight of heavy metals.

[0078] The feedstock of the process according to the invention comprises at least 5% by weight of a tire pyrolysis oil relative to the total weight of the feedstock. Said feedstock may consist solely of tire pyrolysis oil(s).

[0079] The charge may also include, in addition to at least 5% by weight of tire pyrolysis oil, any other pyrolysis oil, including plastic pyrolysis oil and / or solid recovered fuels (SRF), in any proportion.

[0080] Said charge may consist solely of tire pyrolysis oil(s) and plastic pyrolysis oil(s) and / or RDF. In this case, the charge comprises tire pyrolysis oil in a content of between 5 and 99% by weight, preferably between 5 and 80% by weight, and particularly preferably between 5 and 50% by weight, and plastic pyrolysis oil and / or RDF in a content of between 1 and 95% by weight relative to the total weight of the charge, preferably between 20 and 95% by weight, and particularly preferably between 50 and 95% by weight.

[0081] Said charge may comprise at least 50% by weight, preferably between 70 and 100% by weight, of pyrolysis oil, of which at least 5% by weight is tire pyrolysis oil, relative to the total weight of the charge, i.e. preferably between 50 and 100% by weight, preferably between 70% and 100% by weight of pyrolysis oil of which at least 5% by weight is tire pyrolysis oil.

[0082] The feed of the process according to the invention may further comprise, at a low content, typically between 1% and 50% by weight of the feed, or even between 1% and 30% or between 1% and 10% by weight, in addition to tire pyrolysis oil and possibly plastics pyrolysis oil and / or RDF, a conventional petroleum feed or a feed from biomass conversion which is then co-treated with the pyrolysis oil of the feed.

[0083] The conventional petroleum feed can advantageously be a cut or a mixture of cuts of the naphtha, diesel or vacuum diesel type.

[0084] The feedstock resulting from biomass conversion can advantageously be chosen from vegetable oils, algae or algal oils, fish oils, Used cooking oils and fats of vegetable or animal origin; or mixtures of such fillers. These vegetable oils may advantageously be crude or refined, wholly or partially, and derived from plants selected from rapeseed, sunflower, soybean, palm, olive, coconut, copra, castor, cottonseed, peanut, linseed, and crambe oils, and all oils derived, for example, from sunflower or rapeseed by genetic modification or hybridization, this list not being exhaustive. These animal fats are advantageously selected from lard and fats composed of residues from the food industry or from the catering industry. Frying oils, various animal oils such as fish oil, tallow, and lard may also be used.The feedstock from biomass conversion can also advantageously be chosen from methyl esters of fatty acids of vegetable and / or animal origin, or from methyl esters of fatty acids from used edible vegetable oils.

[0085] The feedstock resulting from biomass conversion can also be selected from feedstocks obtained from thermal or catalytic biomass conversion processes, such as oils produced from biomass, particularly lignocellulosic biomass, using various liquefaction methods, such as hydrothermal liquefaction or pyrolysis. The term "biomass" refers to material derived from recently living organisms, including plants, animals, and their by-products. The term "lignocellulosic biomass" refers to biomass derived from plants or their by-products. Lignocellulosic biomass is composed of carbohydrate polymers (cellulose, hemicellulose) and an aromatic polymer (lignin).

[0086] The feed from biomass conversion can also advantageously be chosen from feeds from the paper industry. Pre-treatment (optional)

[0087] Said feed comprising tire pyrolysis oil can advantageously be pretreated in at least one optional pretreatment step, prior to optional selective hydrogenation step a) and / or hydrogenation step b), to obtain a pretreated feed that feeds step a) and / or step b).

[0088] According to one embodiment, this optional pretreatment step reduces the quantity of contaminants and solid particles. In particular, this optional pretreatment step allows for the removal of sediments that may form due to the instability of pyrolysis oils and / or a compatibility issue between two different feedstocks.

[0089] This optional pretreatment step can be implemented by any method known to those skilled in the art that reduces the amount of contaminants. It may, in particular, include an adsorption step and / or a step filtration and / or a centrifugation step and / or a decantation step and / or an electrostatic separation step and / or a washing step using an aqueous solution and / or a gas stripping step.

[0090] The optional pretreatment step is advantageously carried out at a temperature between 20 and 400°C, preferably between 40 and 350°C, and at a pressure between 0.15 and 10.0 MPa abs, preferably between 0.2 and 7.0 MPa abs.

[0091] According to one embodiment, said optional pretreatment step is carried out in an adsorption section operated in the presence of at least one adsorbent. The adsorbent may be selected from zeolite, activated carbon, clay, silica, or alumina. Advantageously, said adsorbent comprises less than 1% by weight of metallic elements, preferably being free of metallic elements. By metallic elements of the adsorbent, we mean the elements of groups VIB, VIIB, and VIII.

[0092] According to another embodiment, the optional pretreatment step is carried out in a washing section with an aqueous solution, for example, water or an acidic or basic solution, or with an organic solvent. This washing section may include equipment for contacting the feed with the aqueous solution and separating the phases so as to obtain the pretreated feed on the one hand and the aqueous solution containing impurities on the other. This equipment may include, for example, a stirred reactor, a decanter, a mixer-decanter, and / or a co-current or counter-current washing column.

[0093] According to another embodiment, the optional pretreatment step is carried out by filtration. The filtration step removes inorganic solids, sediments, and / or fines contained in the feed, including metals, metal oxides, and metal chlorides. A filter with a pore size (e.g., diameter or equivalent diameter) of less than 25 pm is generally used, preferably less than or equal to 10 pm, and even more preferably less than or equal to 5 pm. Alternatively, a series of filters with different pore sizes can be used, in particular a series of filters with decreasing pore sizes in the direction of feed flow. These filter media are well known for industrial applications. Cartridge filters and self-cleaning filters are suitable examples.

[0094] According to one variant, filtration aids, for example diatomaceous earths, can be used in the filtration system, by seeding, i.e. in suspension in the charge or as a pre-coat on the filter.

[0095] Regardless of the filters, especially those with additives, two filters can be used in parallel to perform unclogging and maintenance on one, while the other is in operation.

[0096] According to another variant, said optional pretreatment step is carried out by centrifugation, by decantation or by electrostatic separation.

[0097] According to another embodiment, the optional pretreatment step is implemented by gas stripping, thereby reducing the oxygen content in the feed. Gas stripping can remove oxygen (O2) that may be dissolved in the feed, thereby reducing the likelihood of free radical formation leading to polymerization in downstream steps. The process generally involves contacting the feed with a stripping gas (e.g., H2, N2, or a mixture thereof), thereby transferring at least some of the dissolved oxygen from the feed or the cut to the stripping gas, followed by separation of the stripping gas from the feed. Any dissolved H2 remaining in the feed after the gas stripping step is not a problem, given the downstream hydrogenation steps.

[0098] Said optional pretreatment step generally includes one or more, preferably several treatments described above.

[0099] Said optional pretreatment step thus makes it possible to obtain a pretreated feed which then feeds the hydrogenation step b) and / or the selective hydrogenation step a) when it is present. Step a) Selective hydrogenation (optional)

[0100] According to the invention, the process optionally includes a step a) of selective hydrogenation carried out in a reaction section employing at least one fixed-bed reactor having n catalytic beds, n being an integer greater than or equal to 1, each comprising at least one selective hydrogenation catalyst, said selective hydrogenation reaction section being fed at least by said feed and a gaseous stream comprising hydrogen, in the presence of at least one selective hydrogenation catalyst, at an average temperature between 100 and 280°C, a partial pressure of hydrogen between 1.0 and 10.0 MPa abs. and an hourly volumetric velocity between 0.3 and 10.0 h1, to obtain a selectively hydrogenated effluent.

[0101] The selective hydrogenation step is carried out under hydrogen pressure and temperature conditions that maintain the feedstock in the liquid phase and with just the amount of soluble hydrogen necessary for the selective hydrogenation of the diolefins present in the feedstock. Selective hydrogenation of the diolefins in the liquid phase thus avoids, or at least limits, the formation of "gums," i.e., the polymerization of the diolefins and therefore the formation of oligomers and polymers, which can clog the reaction section of downstream steps b) and c). This selective hydrogenation step yields a selectively hydrogenated effluent, i.e., an effluent with a reduced olefin content, particularly diolefins, and preferably free of diolefins.

[0102] Said reaction section implements a selective hydrogenation, in a fixed bed, in the presence of at least one selective hydrogenation catalyst, advantageously at an average temperature between 100 and 280°C, preferably between 110 and 250°C, preferably between 130 and 200°C, a partial pressure of hydrogen between 1.0 and 10.0 MPa abs. preferably between 1.5 and 8.0 MPa abs. and most preferably between 2.0 and 6.0 MPa abs. and at a volumetric rate per hour (WH) between 0.1 and 10.0 h 1 , preferably between 0.2 and 5.0 h1 , and most preferably between 0.3 and 3.0 h1 .

[0103] According to the invention, the "average temperature" of a reaction section corresponds to the Weight Average Bed Temperature (WABT), a term well known to those skilled in the art. The average temperature is advantageously determined based on the catalytic systems, equipment, and their configuration used. The average temperature (or WABT) is calculated as follows:

[0104] [Math.l] WABT = (T^ +

[0105] with Tinlet: the temperature of the flow at the inlet of the reaction section and Toutlet: the temperature of the effluent at the outlet of the reaction section. Unless otherwise specified, the "average temperature" of a reaction section is given at the start of the cycle.

[0106] The hourly volumetric velocity (WH) is defined here as the ratio between the hourly volumetric flow rate of the charge and the volume of catalyst(s).

[0107] The quantity of the gaseous flow comprising hydrogen (H2), feeding said reaction section of step a), is advantageously such that the hydrogen coverage is between 1 and 200 Nm3 of hydrogen per m3 of charge (Nm3 / m3), preferably between 1 and 150 Nm3 of hydrogen per m3 of charge (Nm3 / m3), preferably between 5 and 100 Nm3 of hydrogen per m3 of charge (Nm3 / m3).

[0108] Hydrogen coverage is defined as the ratio of the volumetric flow rate of hydrogen taken under normal temperature and pressure conditions to the volumetric flow rate of the feed, without taking into account a recycled fraction, at 15°C (in normal m3, noted Nm3, of H2 per m3 of feed).

[0109] The gaseous flow comprising hydrogen, which feeds the reaction section of step a), may consist of a hydrogen make-up and / or recycled hydrogen from in particular the separation step d).

[0110] Advantageously, the reaction section of said selective hydrogenation step comprises between 1 and 5 reactors. According to a particular embodiment of the invention, the reaction section comprises between 2 and 5 reactors, which operate in a switchable mode, referred to in English as "PRS" for Permutable Reactor The PRS system, also known as the "lead and lag" system, involves combining at least two reactors in PRS mode. This allows one reactor to be isolated, the spent catalyst to be discharged, the reactor to be refilled with fresh catalyst, and the reactor to be restarted without interrupting the process. PRS technology is described, in particular, in patent FR2681871.

[0111] Advantageously, reactor internals, for example of the filter plate type, can be used to prevent clogging of the reactor(s). An example of a filter plate is described in patent FR3051375.

[0112] Advantageously, said at least selective hydrogenation catalyst comprises a support, preferably mineral, and a hydro-dehydrogenating function.

[0113] The hydro-dehydrogenating function comprises, in particular, at least one element from Group VIII, preferably selected from nickel and cobalt, and / or at least one element from Group VIB, preferably selected from molybdenum and tungsten. The total oxide content of the metallic elements from Groups VIB and VIII (i.e., the sum of the metallic elements from Groups VIB and VIII) is preferably between 1% and 40% by weight, and preferably between 5% and 30% by weight, relative to the total weight of the catalyst. The weight ratio, expressed as a metal oxide, of the metal(s) from Group VIB to the metal(s) from Group VIII is preferably between 1 and 20, and preferably between 2 and 10.For example, the selective hydrogenation catalyst comprises between 0.5% and 10% by weight of nickel, preferably between 1% and 5% by weight of nickel (expressed as nickel oxide NiO relative to the weight of said catalyst), and between 1% and 30% by weight of molybdenum, preferably between 3% and 20% by weight of molybdenum (expressed as molybdenum oxide MoO3 relative to the weight of said catalyst) on a preferably mineral support.

[0114] The support for said at least one selective hydrogenation catalyst is preferably selected from alumina, silica, silica-aluminas, magnesia, clays, and mixtures thereof. This support may contain dopant compounds, in particular oxides selected from boron oxide, especially boron trioxide, zirconia, cerium, titanium dioxide, phosphoric anhydride, and mixtures thereof. Preferably, said selective hydrogenation catalyst comprises an alumina support, preferably doped with phosphorus and optionally boron. When phosphoric anhydride (P₂O₅) is present, its concentration is less than 10% by weight relative to the alumina and advantageously at least 0.001% by weight relative to the total alumina.When boron trioxide (B2O3) is present, its concentration is less than 10% by weight relative to the weight of the alumina and advantageously at least 0.001% relative to the total weight of the alumina. The alumina used may be, for example, a gamma (γ) or β (β) alumina.

[0115] Said selective hydrogenation catalyst is for example in the form of extrudates.

[0116] According to another aspect of the invention, the selective hydrogenation catalyst as described above further comprises one or more organic compounds containing oxygen and / or nitrogen and / or sulfur. Such a catalyst is often referred to as an "additized catalyst." Generally, the organic compound is chosen from among compounds having one or more chemical functionalities selected from among a carboxyl group, alcohol, thiol, thioether, sulfone, sulfoxide, ether, aldehyde, ketone, ester, carbonate, amine, nitrile, imide, oxime, urea, and amide, or compounds including a furan ring, or sugars.

[0117] Preferably, the selective hydrogenation step may implement, upstream of the selective hydrogenation catalyst(s), at least one guard bed containing adsorbents such as alumina, silica-alumina, zeolite, and / or activated carbon, possibly containing metals from groups VIB and / or VIII in the selective hydrogenation section. Alternatively, a series of guard beds with particles of different diameters may be used, in particular a series of guard beds with diameters decreasing in the direction of the feed flow (also called "grading" in Anglo-Saxon terminology).

[0118] The impurity content, particularly diolefins, of the selectively hydrogenated effluent obtained at the end of the selective hydrogenation step is reduced compared to that of the same impurities, particularly diolefins, contained in the feed. The selective hydrogenation step (a) converts at least 60% and preferably at least 70% of the diolefins contained in the feed. The selectively hydrogenated effluent obtained at the end of the selective hydrogenation step (a) is sent at least partially and preferably entirely, preferably directly, to the hydrogenation step (b). Step b) of hydrogenation

[0119] According to the invention, the process comprises a hydrogenation step b) carried out in a hydrogenation reaction section, employing at least one fixed-bed reactor having n catalytic beds, n being an integer greater than or equal to 1, each comprising at least one hydrogenation catalyst, said hydrogenation reaction section being fed at least by said feed or said selectively hydrogenated effluent from step a) and a gas stream comprising hydrogen, said hydrogenation reaction section being carried out at an average temperature between 140 and 400°C, a partial pressure of hydrogen between 1.0 and 10.0 MPa abs. and an hourly volumetric velocity between 0.1 and 10.0 h1, to obtain a hydrogenated effluent.

[0120] Step b) is in particular carried out under hydrogen pressure and temperature conditions enabling the hydrogenation of diolefins, possibly remaining after the optional selective hydrogenation step, and of olefins at the beginning of the hydrogenation reaction section, while a rising temperature profile allows for hydrodemetallation and hydrodechlorination, particularly at the end of the hydrogenation reaction section. A sufficient quantity of hydrogen is injected to enable the hydrogenation of at least some of the diolefins and olefins present in the pyrolysis oil, the hydrodemetallation of at least some of the metals, notably the retention of silicon, and also the conversion of at least some of the chlorine (to HCl). The hydrogenation of the diolefins and olefins thus prevents, or at least limits, the formation of "gums," i.e., the polymerization of the diolefins and olefins and therefore the formation of oligomers and polymers, which can clog the reaction section of step c) of hydrotreating.In parallel with hydrogenation, hydrometallation, and in particular the retention of silicon during step b), helps to limit the catalytic deactivation of the reaction section in step c) of hydrotreating. Furthermore, the conditions of step b) allow for the conversion of at least some of the chlorine.

[0121] A person skilled in the art will easily understand that, in step b) of hydrogenation, hydrogenation reactions such as those described above are carried out, but also in parallel some of the other hydrotreating reactions, and in particular hydrodesulfurization and hydrodeazotation, even if these reactions are rather favoured in step c) of hydrotreating, which is generally carried out at a higher temperature.

[0122] The temperature in step b) whether it be the average temperature (WABT), the temperature at the inlet of the reaction section or the temperature rise in step b) between inlet and outlet of the reaction section can in particular be controlled by injecting a diluent into step b), preferably a recycle of a part of the hydrocarbon effluent from step d) (or dl)) and / or at least a part of one or more cuts from step e), in particular by the recycle rate and / or by the temperature of the recycled effluent.

[0123] Said reaction section implements hydrogenation in the presence of at least one hydrogenation catalyst, advantageously at an average temperature (or WABT as defined below) between 140 and 400°C, preferably between 240 and 350°C, and particularly preferably between 260 and 330°C, a partial pressure of hydrogen between 1.0 and 10.0 MPa abs, preferably between 1.5 and 8.0 MPa abs. and at a volumetric hourly rate (WH) between 0.1 and 10.0 h1, preferably between 0.2 and 5.0 h1, and most preferably between 0.3 and 3.0 h1.

[0124] The quantity of the gaseous flow comprising hydrogen (H2), feeding said reaction section of step b), is advantageously such that the hydrogen coverage is between 100 and 1500 Nm3 of hydrogen per m3 of feed (Nm3 / m3), preferably between 200 and 1000 Nm3 of hydrogen per m3 of feed (Nm3 / m3), so preferred between 250 and 800 Nm3 of hydrogen per m3 of charge (Nm3 / m3).

[0125] The definitions of mean temperature (WABT), WH and hydrogen cover correspond to those described above in step a).

[0126] Hydrogen can be obtained from a fossil source or from a renewable source, for example from the gasification of plastic waste or produced by electrolysis.

[0127] Advantageously, the reaction section of said step b) comprises between 1 and 5 reactors, preferably between 2 and 5 reactors, and particularly preferably comprises two reactors. The advantage of a hydrogenation reaction section comprising several reactors lies in optimized feedstock processing, while reducing the risk of fouling of the catalytic bed(s) and thus preventing unit shutdown due to fouling.

[0128] According to a preferred embodiment, these reactors operate in a switchable mode, known as a "PRS" (Permutable Reactor System) or "lead and lag." Combining at least two reactors in PRS mode allows one reactor to be isolated, the spent catalyst to be discharged, the reactor to be refilled with fresh catalyst, and the reactor to be restarted without interrupting the process. The PRS technology is described, in particular, in patent FR2681871.

[0129] According to a particularly preferred embodiment, the hydrogenation reaction section of step b) comprises two reactors operating in switchable mode.

[0130] The hydrogenation reaction section employing at least one fixed-bed reactor can operate with downward or upward flow of gas and liquid.

[0131] Advantageously, reactor internals, for example of the filter plate type, can be used to prevent clogging of the reactor(s). An example of a filter plate is described in patent FR3051375.

[0132] Advantageously, said hydrogenation catalyst comprises a support, preferably mineral, and a hydro-dehydrogenating function.

[0133] According to one embodiment, the hydro-dehydrogenating function comprises, in particular, at least one element from Group VIII, preferably selected from nickel and cobalt, and at least one element from Group VIB, preferably selected from molybdenum and tungsten. According to this embodiment, the total content, expressed as oxides, of the metallic elements from Groups VIB and VIII is preferably between 1% and 40% by weight, preferably from 5% to 30% by weight relative to the total weight of the catalyst. When the metal is cobalt or nickel, the metal content is expressed as CoO and NiO, respectively. When the metal is molybdenum or tungsten, the metal content is expressed as MoO3 and WO3, respectively. The weight ratio, expressed as metal oxide, of the metal (or metals) from Group VIB relative to the metal (or metals) from Group VIII is preferably between 1 and 20, and preferably between 2 and 10.

[0134] According to this variant, the reaction section of said step b) comprises for example a hydrogenation catalyst comprising between 0.5% and 12% by weight of nickel, preferably between 0.9% and 10% by weight of nickel (expressed as nickel oxide NiO relative to the weight of said catalyst), and between 1% and 30% by weight of molybdenum, preferably between 3% and 20% by weight of molybdenum (expressed as molybdenum oxide MoO3 relative to the weight of said catalyst) on a support preferably mineral, preferably on an alumina support.

[0135] According to another embodiment, the hydro-dehydrogenating function comprises, and preferably consists of, at least one element from Group VIII, preferably nickel. According to this embodiment, the nickel oxide content is preferably between 1 and 50% by weight, preferably between 10% and 30% by weight relative to the weight of said catalyst. This type of catalyst is preferably used in its reduced form, on a support, preferably mineral, preferably on an alumina support.

[0136] The support for said hydrogenation catalyst is preferably selected from alumina, silica, silica-aluminas, magnesia, clays, and mixtures thereof. This support may contain dopant compounds, in particular oxides selected from boron oxide, especially boron trioxide, zirconia, cerium, titanium dioxide, phosphoric anhydride, and mixtures thereof. Preferably, said hydrogenation catalyst comprises an alumina support, optionally doped with phosphorus and optionally with boron. When phosphoric anhydride (P₂O₅) is present, its concentration is less than 10% by weight relative to the weight of the alumina and advantageously at least 0.001% by weight relative to the total weight of the alumina. When boron trioxide B2O3 is present, its concentration is less than 10% by weight relative to the weight of alumina and advantageously at least 0.001% relative to the total weight of alumina.The alumina used can be, for example, a y (gamma) or q (eta) alumina.

[0137] Said hydrogenation catalyst is for example in the form of extrudates.

[0138] Preferably, step b) may implement, in addition to the hydrogenation catalyst(s) described above, at least one further hydrogenation catalyst used in step b) comprising less than 1% by weight of nickel and at least 0.1% by weight of nickel, preferably 0.5% by weight of nickel, expressed as nickel oxide NiO by weight of said catalyst, and less than 5% by weight of molybdenum and at least 0.1% by weight of molybdenum, preferably 0.5% by weight of molybdenum, expressed as molybdenum oxide MoO3 by weight of said catalyst, on an alumina support. This low-metal content catalyst may preferably be placed upstream or downstream of the hydrogenation catalyst(s) described above, preferably upstream.

[0139] Preferably, step b) may implement upstream of the hydrogenation catalyst(s) at least one guard bed containing adsorbents of the type alumina, silica-alumina, zeolite and / or activated carbon possibly containing metals of group VIB and / or VIII. A series of guard beds with particles of different diameters may also be used, in particular a series of guard beds having diameters decreasing in the direction of the flow of the charge (also called "grading" according to Anglo-Saxon terminology).

[0140] Said hydrogenation step b) makes it possible to obtain a hydrogenated effluent, that is to say, an effluent with a reduced content of olefins, in particular diolefins, and of metals, in particular silicon, and of halogens, in particular chlorine. Hydrogenation step b) generally makes it possible to convert at least 40%, and preferably at least 60%, of the diolefins and at least 40%, and preferably at least 60%, of the olefins contained in the initial feed. The heat released by the saturation of the double bonds makes it possible to raise the temperature of the reaction medium and to initiate the hydrotreating reactions, in particular the removal, at least in part, of other contaminants, such as silicon and chlorine or nitrogen. Preferably, at least 50%, and more preferably at least 75%, of the chlorine and silicon of the initial feed are respectively removed during step a).Generally, the silicon content is less than 10 ppm by weight in the hydrogenated effluent of step b).

[0141] When step d) of separation is carried out after step c) of hydrotreatment, the hydrogenated effluent obtained at the end of step b) of hydrogenation is sent at least in part and preferably in full, preferably directly, to step c) of hydrotreatment.

[0142] When step d) of separation is carried out between steps b) and c), the hydrogenated effluent obtained at the end of step b) of hydrogenation is sent, at least in part and preferably in whole, preferably directly, to step d) of separation. Step c) of hydrotreatment

[0143] According to the invention, the treatment process comprises a hydrotreating step (c) carried out in a hydrotreating reaction section, employing at least one fixed-bed reactor having n catalytic beds, n being an integer greater than or equal to 1, each comprising at least one hydrotreating catalyst, said hydrotreating reaction section being fed at least by said hydrocarbon effluent from step (d) when separation step (d) is carried out between steps (b) and (c), and / or at least by the hydrogenated effluent from step (b) when separation step (d) is carried out after step (c), and a gas stream comprising hydrogen, said hydrotreating reaction section being carried out at a average temperature between 250 and 430°C, a partial pressure of hydrogen between 1.0 and 10.0 MPa abs. and an hourly volumetric velocity between 0.1 and 10.0 h1, to obtain a hydrotreated effluent.

[0144] Advantageously, step c) implements hydrotreating reactions well known to those skilled in the art, and more particularly hydrotreating reactions such as aromatic hydrogenation, hydrodesulfurization, and hydrodeazotation. In addition, the hydrogenation of the remaining olefins and halogenated compounds, as well as hydrodemetallation, are carried out.

[0145] Said hydrotreating reaction section is advantageously implemented at a pressure equivalent to that used in the reaction section of step b) of hydrogenation, and generally at a higher average temperature than that of the reaction section of step b) of hydrogenation. Thus, said hydrotreating reaction section is advantageously implemented at an average hydrotreating temperature between 250 and 430°C, preferably between 280 and 380°C, at a partial pressure of hydrogen between 1.0 and 10.0 MPa abs. and at a volumetric rate per hour (WH) between 0.1 and 10.0 h1, preferably between 0.1 and 5.0 h1, preferably between 0.2 and 2.0 h1, preferably between 0.2 and 1h'.The hydrogen coverage in step c) is advantageously between 100 and 1500 Nm3 of hydrogen per m3 of fresh feed, and preferably between 200 and 1000 Nm3 of hydrogen per m3 of fresh feed, and more preferably between 250 and 800 Nm3 of hydrogen per m3 of fresh feed. The definitions of mean temperature (WABT), WH, and hydrogen coverage correspond to those described above.

[0146] Advantageously, the reaction section of said step c) comprises between 1 and 5 reactors, preferably between 2 and 5 reactors. These reactors can operate in series and / or in parallel and / or in switchable mode (or PRS).

[0147] In a preferred mode, said hydrotreating reaction section comprises a single fixed-bed reactor containing n catalytic beds, n being an integer greater than or equal to one, preferably from one to ten, and preferably from two to five. In a particularly preferred mode, the hydrogenation reaction section of step b) comprises two reactors operating in switchable mode followed by the hydrotreating reaction section of step c) which comprises a single fixed-bed reactor.

[0148] The hydrotreating reaction section employing at least one fixed-bed reactor can operate with downward or upward flow of gas and liquid.

[0149] Advantageously, reactor internals, for example of the filter tray type, can be used to prevent clogging of the reactor(s).

[0150] Advantageously, said hydrotreating catalyst used in said step c) may be chosen from among known catalysts for hydrodemetallation, hydrotreating, silicon capture, used in particular for the treatment of petroleum fractions, and their combinations. Examples of known hydrometallation catalysts are those described in patents EP 0113297, EP 0113284, US 5221656, US 5827421, US 7119045, US 5622616, and US 5089463. Examples of known hydrotreating catalysts are those described in patents EP 0113297, EP 0113284, US 6589908, US 4818743, and US 6332976. Examples of known silicon capture catalysts are those described in patent applications CN 102051202 and US 2007 / 080099.

[0151] In particular, said hydrotreating catalyst comprises a support, preferably mineral, and at least one metallic element having a hydro-dehydrogenating function. Said metallic element having a hydro-dehydrogenating function advantageously comprises at least one element from Group VIII, preferably selected from the group consisting of nickel and cobalt, and / or at least one element from Group VIB, preferably selected from the group consisting of molybdenum and tungsten. The total content, expressed as oxides of the metallic elements from Groups VIB and VIII, is preferably between 0.1% and 40% by weight, preferably from 5% to 35% by weight, relative to the total weight of the catalyst. When the metal is cobalt or nickel, the metal content is expressed as CoO and NiO, respectively. When the metal is molybdenum or tungsten, the metal content is expressed as MoO3 and WO3, respectively.The weight ratio, expressed as metal oxide, of the metal (or metals) of Group VIB to the metal (or metals) of Group VIII is preferably between 1.0 and 20, preferably between 2.0 and 10. For example, the hydrotreating reaction section comprises a hydrotreating catalyst comprising between 0.5% and 10% by weight of nickel, preferably between 1% and 8% by weight of nickel, expressed as nickel oxide NiO relative to the total weight of the hydrotreating catalyst, and between 1.0% and 30% by weight of molybdenum, preferably between 3.0% and 29% by weight of molybdenum, expressed as molybdenum oxide MoO3 relative to the total weight of the hydrotreating catalyst, on a mineral support, preferably on an alumina support.

[0152] The support for said hydrotreating catalyst is advantageously selected from alumina, silica, silica-aluminas, magnesia, clays, and mixtures thereof. This support may further contain doping compounds, in particular oxides selected from boron oxide, especially boron trioxide, zirconia, cerium, titanium dioxide, phosphoric anhydride, and mixtures thereof. Preferably, said hydrotreating catalyst comprises an alumina support, more preferably an alumina support doped with phosphorus and optionally boron. When phosphoric anhydride (P₂O₅) is present, its concentration is in less than 10% by weight relative to the weight of the alumina and advantageously at least 0.001% by weight relative to the total weight of the alumina. When boron trioxide (B₂O₃) is present, its concentration is less than 10% by weight relative to the weight of the alumina and advantageously at least 0.001% relative to the total weight of the alumina. The alumina used may be, for example, gamma (γ) or eth (β) alumina.

[0153] Said hydrotreating catalyst is for example in the form of extrudates.

[0154] Advantageously, said hydrotreating catalyst of the process has a specific surface area of ​​between 200 and 800 m² / g, preferably between 250 and 600 m² / g, and more preferably between 300 and 400 m² / g. The specific surface area of ​​the hydrotreating catalyst is measured by the BET method, that is, the specific surface area determined by nitrogen adsorption in accordance with ASTM D 3663-78, established from the Brunauer-Emmett-Teller method described in the periodical 'The Journal of the American Chemical Society', 6Q, 309 (1938). Such a specific surface area further improves the removal of contaminants, particularly metals such as silicon.

[0155] According to another aspect of the invention, the hydrotreating catalyst as described above further comprises one or more organic compounds containing oxygen and / or nitrogen and / or sulfur as described above (additized catalyst).

[0156] Preferably, step c) may implement upstream of the hydrotreating catalyst(s) at least one guard bed or a series of guard beds of the "grading" type as described above for step b).

[0157] Advantageously, hydrotreating step c) enables the hydrogenation of at least 80%, and preferably all, of the olefins and halogenated compounds remaining after hydrogenation step b), but also the conversion, at least in part, of other impurities present in the feedstock, such as aromatic compounds, metallic compounds, sulfur compounds, nitrogen compounds, and oxygenated compounds. Preferably, the nitrogen content at the outlet of step c) is less than 100 ppm by weight, and preferably less than 10 ppm by weight. Preferably, the sulfur content at the outlet of step c) is less than 100 ppm by weight, and preferably less than 10 ppm by weight. Step c) can also further reduce the content of contaminants, such as metals, in particular silicon.Preferably, the metal content at the outlet of step d) is less than 10 ppm by weight, and preferably less than 2 ppm by weight, and the silicon content is less than 5 ppm by weight. Preferably, the halogen element content at the outlet of step c) is less than 5 ppm by weight.

[0158] The preparation of the catalysts for the selective hydrogenation, hydrogenation, hydrotreating and hydrocracking steps (see below) is known and The process generally includes an impregnation step with Group VIII and Group VIB metals (when present), and possibly phosphorus and / or boron on the support, followed by drying and then possibly calcination. In the case of an additive catalyst, preparation is generally carried out by simple drying without calcination after the introduction of the organic compound. Calcination is defined here as heat treatment under a gas containing air or oxygen at a temperature of 200°C or higher. Before their use in a process step, catalysts are generally subjected to sulfidation to form the active species.

[0159] Depending on the sulfur content in the initial feed to be treated, a stream containing a sulfurizing agent may be injected upstream of the optional pretreatment step, the optional selective hydrogenation step a) and / or the hydrogenation step b) and / or the hydrotreating step c) and / or upstream of one of the optional hydrocracking steps when present, preferably upstream of the hydrogenation step b) and / or the hydrotreating step c) in order to ensure a sufficient quantity of sulfur to form the active species of the catalyst (in sulfide form).

[0160] This activation or sulfidation step is carried out by methods well known to those skilled in the art, and advantageously under a sulfur-reducing atmosphere in the presence of hydrogen and hydrogen sulfide. The sulfidating agents are preferably H2S gas, elemental sulfur, CS2, mercaptans, sulfides and / or polysulfides, hydrocarbon fractions with a boiling point below 400°C containing sulfur compounds, or any other sulfur-containing compound used for activating hydrocarbon feedstocks in order to sulfide the catalyst. Said sulfur-containing compounds are advantageously chosen from among alkyl disulfides such as, for example, dimethyl disulfide (DMDS), alkyl sulfides, such as, for example, dimethyl sulfide, thiols such as, for example, n-butylmercaptan (or 1-butanethiol) and polysulfide compounds of the tertiononylpolysulfide type.The catalyst can also be sulfided by the sulfur contained in the feed to be desulfurized. Preferably, the catalyst is sulfided in situ in the presence of a sulfurizing agent and a hydrocarbon feed. Most preferably, the catalyst is sulfided in situ in the presence of the feed supplemented with dimethyl disulfide.

[0161] The injection of a sulfurizing agent is particularly necessary at the beginning of the catalytic cycle, while the H2S is being formed. Additional injections throughout the catalytic cycle may be necessary to compensate for natural losses. However, using a tire pyrolysis oil with a high sulfur content significantly reduces the consumption of the sulfurizing agent, or even eliminates its use entirely. Step d) separation

[0162] According to the invention, the treatment process comprises a separation step d) carried out between steps b) and c) and / or after step c), said step being fed with the hydrogenated effluent from step b) when the separation step d) is carried out between steps b) and c), and / or with the hydrotreated effluent from step c) when the separation step d) is carried out after step c), and an aqueous solution, said step being carried out in a separation section, to obtain at least a gaseous effluent, an aqueous effluent and a hydrocarbon effluent.

[0163] This washing / separation step makes it possible in particular to remove ammonium chloride salts, which are formed by reaction between chloride ions, released by the hydrogenation of chlorinated compounds in the form of HCl, in particular during the hydrogenation step and subsequent dissolution in water, and ammonium ions, generated by the hydrogenation of nitrogen compounds in the form of NH3 during the hydrotreatment step and / or supplied by the injection of an amine and subsequent dissolution in water, and thus to limit the risks of clogging, in particular in the transfer lines and / or in the sections of the process of the invention and / or the transfer lines to the steam cracker, due to the precipitation of ammonium chloride salts.This step also removes hydrochloric acid formed by the reaction of hydrogen ions and halide ions released by the hydrogenation of halogenated compounds during the hydrogenation and possibly hydrotreating steps, which dissolve in the aqueous solution. When H2S is present in the hydrotreated effluent from the hydrotreating step, the washing / separation step also removes ammonium sulfide salts ((NH4)2S) that form by the reaction between H2S from the hydrodesulfurization of sulfide compounds and NH3, dissolving them in the aqueous solution.

[0164] The washing / separation step is advantageously carried out at a temperature between 50 and 450°C, preferably between 100 and 440°C, most preferably between 200 and 420°C, and particularly preferably between 250 and 420°C. It is important to operate within this temperature range (and therefore not to overcool the hydrotreatment effluent) to avoid the risk of blockages in the lines due to the precipitation of ammonium chloride salts. Advantageously, the washing / separation step is carried out at a pressure close to that used in the hydrogenation or hydrotreatment step, preferably between 1.0 and 10.0 MPa abs, in order to facilitate hydrogen recycling.

[0165] The aqueous solution can be water. It can also be a basic aqueous solution (for example, by adding NaOH). Using a basic solution neutralizes hydrogen halides and any dissolved salts.

[0166] Said separation section may include any means of separation known to those skilled in the art, in particular one or more expansion balloons arranged in series, and / or one or more steam and / or hydrogen stripping columns, and / or an atmospheric distillation column, and / or a vacuum distillation column. The washing / separation step can advantageously be carried out in common or separate washing and separation equipment, such equipment being well known (separating vessels capable of operating at different pressures and temperatures, pumps, heat exchangers, washing columns, etc.).

[0167] Advantageously, the washing / separation step includes an injection of an aqueous solution, preferably an injection of water, into the hydrogenated effluent and / or the hydrotreated effluent, upstream of the washing / separation section, so as to dissolve at least part and preferably all of the hydrogen halides (HCl in particular) and any salts present.

[0168] In a possible embodiment of the invention, the washing / separation step comprises the injection of an aqueous solution into the hydrogenated effluent and / or the hydrotreated effluent, followed by the washing / separation section advantageously comprising a separation phase enabling the production of at least one aqueous effluent containing hydrogen halides (in particular HCl) and any dissolved salts, said hydrocarbon effluent, and a partially washed gaseous effluent. Said aqueous effluent and said hydrocarbon effluent can then be separated in a settling tank to obtain said washed hydrocarbon effluent and said aqueous effluent.The partially washed gaseous effluent can simultaneously be introduced into a scrubbing column where it flows counter-currently to an aqueous stream, preferably of the same nature as the aqueous solution injected into the hydrogenated and / or hydrotreated effluent. This allows for the removal, at least in part, and preferably entirely, of the hydrochloric acid contained in the partially washed gaseous effluent, thus obtaining the gaseous effluent, preferably consisting essentially of hydrogen, and an acidic aqueous stream. The aqueous effluent from the settling tank can optionally be mixed with the acidic aqueous stream and used, possibly mixed with the acidic aqueous stream, in a water recycling circuit to supply the scrubbing / separation stage with the aqueous solution upstream of the scrubbing / separation section and / or with the aqueous stream in the scrubbing column.The said water recycling circuit may include a water top-up and / or a basic solution and / or a purge to remove impurities.

[0169] According to one embodiment, and depending on the content of chlorinated compounds in said feed, a stream containing a nitrogenous compound such as ammonia or an amine, for example monoethanolamine, diethanolamine, monodiethanolamine and / or aniline, may be injected upstream of the selective hydrogenation step and / or upstream of the hydrogenation step and / or upstream of the hydrotreating step in order to ensure a sufficient quantity of ammonium ions to combine the chloride ions formed during The hydrotreating stage uses ammonium chloride salts, thus limiting the formation of hydrochloric acid and consequently reducing corrosion downstream of the separation section. The high nitrogen content in tire pyrolysis oil reduces, or even eliminates, the need for additional nitrogen compounds.

[0170] The aqueous effluent obtained at the end of the washing / separation step advantageously comprises ammonium salts and / or hydrochloric acid.

[0171] Said gaseous effluent obtained at the end of the washing / separation step advantageously comprises hydrogen, preferably comprising at least 60% by volume, preferably at least 70% by volume, of hydrogen. Said gaseous effluent obtained at the end of the washing / separation step contains very little chlorine, generally at a concentration of less than 3 ppm by weight of chlorine, which allows it to be sent to a refining unit requiring hydrogen. According to one embodiment, said gaseous effluent can at least partially be recycled to one of the steps of the process according to the invention requiring hydrogen (steps a), b), c)) and optionally to at least one hydrocracking step when it is / are present), the recycling system being able to include a purification section (for example, for the adsorption of heavy metals such as mercury).

[0172] According to one embodiment, the separation step d) is carried out after the hydrotreating step c). When the separation step d) is carried out after the hydrotreating step c), the hydrocarbon effluent from the separation step d) can be sent, in part or in whole, either directly to the inlet of a steam cracking unit or to an optional fractionation step e). Preferably, the hydrocarbon effluent is sent, in part or in whole, to a fractionation step e. Preferably, the separation step d) is carried out after the hydrotreating step c.

[0173] According to another embodiment, the separation step d) is carried out between steps b) and c). When the separation step d) is carried out between steps b) and c), the hydrocarbon effluent from the separation step d) is sent, at least in part and preferably in whole, preferably directly, to the hydrotreating step c). This embodiment is advantageous when the feedstock contains a large amount of halogenated compounds, particularly chlorinated compounds. Indeed, the chlorine (in the form of HCl) contained in the effluent from the hydrogenation step b) can be deposited on the hydrotreating catalyst in step c), thus leading to a decrease in activity and a reduction in the duration of the catalytic cycle.

[0174] According to another embodiment, the separation step d) can be carried out after step c) and between steps b) and c). In this case, step d) is carried out twice. This embodiment is advantageous for feeds heavily loaded with halogenated compounds, and in particular in chlorinated compounds.

[0175] At least a portion of the hydrocarbon effluent from the separation step d) when the separation step d) is carried out after the hydrotreatment step c), and / or at least a portion of the hydrotreated effluent from the step c) when the separation step d) is carried out between steps b) and c), can be recycled upstream of step b) and / or step c) and / or upstream of the selective hydrogenation step a). Recycling to or upstream of at least one of the reaction steps advantageously allows, on the one hand, the dilution of impurities and, on the other hand, the control of the temperature in the reaction step(s), in which the reactions involved may be highly exothermic. Recycl stream injection can be carried out at the first catalytic bed of the reaction section of steps a), b) and / or c) or between the different catalytic beds of each section.When the reaction section comprises two reactors operating in switchable mode, at least part of the recycle stream can be recycled between the two reactors.

[0176] Advantageously, the quantity of recycled effluent is adjusted so that the weight ratio between the recycle stream and the feed, i.e. the feed to be treated supplying the overall process, is less than or equal to 10, preferably less than or equal to 7, and preferably greater than or equal to 0.001, preferably greater than or equal to 0.01, and preferably greater than or equal to 0.1. Preferably, the quantity of recycle is adjusted so that the weight ratio between the recycle stream and the feed is between 0.01 and 10, preferably between 0.1 and 7, and particularly preferably between 0.2 and 5.

[0177] This recycle rate makes it possible in particular to control the temperature rise in step b). Indeed, when the recycle rate is high, the rate of dilution of the feed is high, and the temperature rise at the beginning of the reaction section of step b), in particular due to the hydrogenation reactions of the diolefins, is thus controllable by the dilution effect.

[0178] Preferably, an additional gas stream including hydrogen is advantageously introduced at the inlet of each reactor, particularly those operating in series, and / or at the inlet of each catalytic bed from the second catalytic bed of the reaction section. These additional gas streams are also called cooling streams. They allow for temperature control in the reactor, in which the reactions carried out are generally highly exothermic. This cooling stream can be injected into the reaction section of step a), b), c), or f).

[0179] According to a preferred embodiment, at least a portion of the recycled effluent may advantageously be either cooled or preheated, if necessary, or kept at the same temperature as at the outlet of separation step d) when separation step d) is carried out after step c) of hydrotreatment, and / or only at the exit of step c) of hydrotreatment when step d) of separation is carried out between steps b) and c), before reintroducing it into the process according to the invention.

[0180] According to one embodiment, the feed, before preferably being mixed with at least a portion of the recycled effluent, can be preheated by direct heating to a temperature of up to 200°C, preferably up to 180°C, and particularly preferably up to 150°C. Above this temperature, contact with a wall during direct heating can induce the formation of gums and / or coke, which can cause fouling and an increase in the pressure drop of the feed heating system as well as of the catalyst bed(s), particularly when a selective hydrogenation step (a) is not carried out. Heating the feed to a temperature above 150°C, preferably above 180°C, and particularly preferably above 200°C, is preferably carried out by indirect heating with a hot diluent, preferably with at least a portion of the recycled effluent.Thus, the temperature rise above 150°C, preferably above 180°C, and particularly preferably above 200°C, of ​​the feedstock is caused by mixing with a hotter liquid, and not by contact with a heated wall. This allows for localized limitation of high temperatures. This type of heating by mixing with a hot inert liquid therefore limits undesirable reactions such as the polymerization of diolefins (gum formation) and / or coke formation, and allows for adjusting the inlet temperature of the flow in step b) so as to initiate the hydrogenation reaction of unsaturates, preferably at the lowest possible temperature, while controlling the exothermicity of these reactions through a dilution effect on the reactive species.

[0181] According to another embodiment, the feed is entirely heated by indirect heating from at least a portion of the recycled effluent. In this case, the feed is not preheated before being mixed with at least a portion of the recycled effluent.

[0182] Another heating stream advantageously consists of a hydrogen-rich gaseous effluent from the hydrogen make-up and / or the gaseous effluent from the separation step d). Variant step d) of two-step separation

[0183] In a possible embodiment of the invention, the separation step d) which can be carried out after step c) and / or between steps b) and c) may comprise two steps, a first separation step carried out "hot", followed by a second separation step carried out "cold".

[0184] This embodiment allows for the clever removal of chlorine in the form of ammonium chloride salts by combining the hot separation step d1) followed by the cold separation / washing step d2). The chloride ions, released by The hydrogenation of chlorinated compounds as HCl in steps b) and c) (hydrodechlorination) and the ammonia generated by the hydrogenation of nitrogen compounds as NH3 in step c) (hydrodeazotation) are largely removed in the gaseous effluent thanks to the hot separation in step d1). Indeed, the high temperature of this separation step d1 prevents the precipitation of ammonium chloride salts, which form through the reaction between chloride and ammonium ions. The separation at a lower temperature in step d2) of the gaseous effluent and a portion of the liquid effluent causes these ammonium chloride salts to precipitate. The water washing in this step d2) dissolves these salts in the aqueous effluent. This yields a hydrocarbon effluent free of chlorine.

[0185] According to this embodiment, step d) of separation may comprise the following steps:

[0186] dl) a separation step, fed by the hydrogenated effluent from step b) when separation step d) is carried out between steps b) and c), and / or by the hydrotreated effluent from step c) when separation step d) is carried out after step c), said step being operated at a temperature above the precipitation temperature of ammonium halides and at a pressure substantially identical to the pressure of step b) to obtain at least a first gaseous effluent and a liquid effluent, part of which may be recycled, as recycled effluent, upstream of step b),

[0187] d2) a separation stage, fed by the first gaseous effluent and even at least a portion of the liquid effluent from step dl), and an aqueous solution, said step being carried out at a temperature lower than the precipitation temperature of ammonium halides and at a pressure substantially the same as or lower than the pressure of step b), to obtain at least a second gaseous effluent, an aqueous effluent and a hydrocarbon effluent.

[0188] When separation step d) is carried out after step c) and between steps b) and c), a (first) separation step d1) can be carried out "hot" (without step d2), followed by a (second) separation step d1) and / or d2) after step c). This results in at least a first gaseous effluent and a liquid effluent being obtained from the first "hot" separation d1) between steps b) and c), a portion of which is recycled upstream of step b). The gaseous effluent and the remaining portion of the liquid effluent are then introduced into hydrotreatment step c). The hydrotreated effluent is then treated according to step d2) (separation "cold" with washing), possibly supplemented by a step d1) after step c). This configuration has the advantage of obtaining a hot recycle which allows the load to be preheated and the exothermicity of this step b) to be controlled while requiring only one wash (after step c) to remove the salts. Step dl) of hot separation

[0189] The high temperature of this separation step dl) prevents the precipitation of ammonium halide salts which are formed by reaction between halide ions and ammonium ions in order to recover a gaseous effluent containing the majority of the halides in the form of hydrogen halides (HCl) and gaseous ammonia, and a liquid effluent containing very little halide and ammonia.

[0190] The "precipitation temperature" of ammonium halides is defined as the temperature (under given conditions, such as concentration and pressure) at which gaseous ammonia and hydrogen halides precipitate, either by reacting to form solid ammonium halide crystals or by dissolving in water. The precipitation temperature depends on the halide concentrations and pressure according to thermodynamic principles. The precipitation temperature of ammonium halides is generally between 150 and 300°C, often between 180 and 295°C, and particularly between 200 and 290°C, under the conditions of use of the present process.

[0191] The temperature at which the separation of step dl) is carried out must be higher than the precipitation temperature of ammonium halides in order to recover a gaseous effluent containing the majority of the halides in the form of hydrogen halides (HCl) and gaseous ammonia, and a liquid effluent containing very little halides and ammonia. The temperature at which the separation of step dl) is carried out is generally between 200 and 450°C, preferably between 220 and 330°C, and particularly preferably between 240 and 300°C.

[0192] The term "pressure substantially equal to the pressure of step b)" means the pressure of step b) with a pressure difference of between 0 and 1 MPa, preferably between 0.005 and 0.3 MPa, and particularly preferably between 0.01 and 0.3 MPa with respect to the pressure of step b). Preferably, the pressure of step dl) is the pressure of step b) less the pressure losses.

[0193] The separation step dl) can advantageously be carried out by any method known to those skilled in the art, such as, for example, the combination of one or more separators (balloons) and / or one or more stripping columns, these separators (balloons) and / or columns optionally being supplied with a stripping gas, for example, a hydrogen-rich gas stream. Preferably, the step dl) is carried out with a single separator (balloon).

[0194] The separation step dl) is a so-called high-pressure or medium-pressure, high-temperature separation step, also known to those skilled in the art as HHPS (for "Hot High Pressure Separator" in Anglo-Saxon terminology). Thus, this step dl) preferably uses a so-called "hot high pressure separator". pressure”, the pressure being substantially equal to the operating pressure of step b).

[0195] The gas / liquid separation has an efficiency corresponding to the solubility and Henry's law. This means that an equilibrium quantity of halides in the form of hydrogen halides will remain in the liquid effluent obtained in step d1). These halides will be released into the gaseous effluent during step d2) of cold separation and then removed by dissolution in the aqueous effluent.

[0196] Advantageously, a portion of the liquid effluent from step dl) is recycled upstream of step b) and / or possibly upstream of step a) as recycled effluent in the quantities of recycle described above. In addition to the advantages of impurity dilution and temperature control as described above, the recycle allows, in particular, indirect heating of the feed or selectively hydrogenated effluent, by simply mixing the "cold" feed or the "cold" selectively hydrogenated effluent with the hot recycle.

[0197] According to a preferred embodiment, at least part of the recycled effluent can advantageously be either cooled, or pre-heated, if necessary, or kept at the same temperature as at the outlet of the separation step dl) when the separation step d) is carried out after the hydrotreatment step c), and / or as at the outlet of the hydrotreatment step c) when the separation step d) is carried out between steps b) and c), before being reintroduced into the process according to the invention.

[0198] High-pressure, high-temperature separation allows, on the one hand, for maximizing energy recovery by hot recycling of a portion of the liquid effluent. Indeed, the energy required to reach the inlet temperature in step b), and / or possibly in step a), is at least partially supplied by the heat from a portion of the recycled effluent from step dl), and also reduces or even eliminates the need for preheating by directly heating the feed above 200°C to prevent gum formation. Furthermore, preferably recycling at least a portion of the liquid effluent at high pressure saves energy for its pressurization in step b).

[0199] High-pressure, high-temperature separation also minimizes the amount of light fraction (naphtha cut) contained in the liquid effluent. At this temperature, almost all of the light fraction of the effluent (naphtha) is released as a gaseous effluent to step d2) of cold separation / washing, while the liquid phase consists mainly of the heavy fraction of the feedstock (middle distillates cut). When recycling part of the liquid effluent to step b), the ppH2 is increased in step b) because the light fraction (naphtha) could partially vaporize and lower the ppH2 if it were not at least partially removed during the high-pressure, high-temperature separation. The removal of the light fraction, including naphtha, can optionally be increased by a slight expansion upstream of at least one se The parator implemented in step d2) is used, although this implementation is not preferred due to the energy loss associated with the expansion. Another option to increase the removal of the light fraction, including naphtha, could be to perform stripping, for example by injecting a hydrogen-rich gas in step d1). Step d2) of cold separation and washing

[0200] According to the invention, the treatment process may include a separation step d2), fed by the first gaseous effluent and optionally at least part of the liquid effluent from step d1) and an aqueous solution, said step being carried out at a temperature lower than the precipitation temperature of ammonium halides, and at a pressure substantially the same as or lower than the pressure of step b), to obtain at least a second gaseous effluent, an aqueous effluent and a hydrocarbon effluent.

[0201] Separation from step d2) at a temperature lower than the precipitation temperature of ammonium halides from the gaseous effluent and possibly at least part of the liquid effluent from step dl) causes the ammonium halide salts which are formed by reaction between halide ions and ammonium ions contained in particular in the gaseous effluent.

[0202] The cold separation step d2 is fed with the gaseous effluent alone from step d1) or with the mixture of the gaseous effluent and at least a portion of the liquid effluent from step d1). Preferably, the cold separation step d2 is fed with the mixture of the gaseous effluent and at least a portion of the liquid effluent. According to one embodiment, the cold separation step d2 is fed with the mixture of the gaseous effluent and all of the liquid effluent. Performing the cold separation step d2 on the mixture of gaseous and liquid effluent has the advantage of extracting not only contaminants from the gaseous effluent, but also hydrogen halides (HCl) dissolved in the liquid effluent. Indeed, the hydrogen halides dissolved in the liquid effluent from step dl) are released and also form ammonium halides with the ammonia present in the gaseous effluent.

[0203] Washing with an aqueous solution in this step d2) allows these salts to dissolve in the aqueous effluent. This yields a hydrocarbon effluent free of halides, a gaseous effluent free of halides, and an aqueous effluent in which the ammonium halide salts are dissolved.

[0204] The temperature at which the separation in step d2) is carried out must be lower than the precipitation temperature of ammonium halides in order to precipitate the ammonium halide salts. The temperature at which the separation in step d2) is carried out is greater than or equal to 20°C and less than 200°C, preferably between 25 and 120°C, and particularly preferably between 30 and 70°C.

[0205] The term "pressure substantially equal to the pressure of step b)" means the pressure of step b) with a pressure difference of between 0 and 1 MPa, preferably between 0.005 and 0.3 MPa, and particularly preferably between 0.01 and 0.3 MPa, relative to the pressure of step b). Preferably, the pressure of step d2) is the pressure of step b) less pressure losses. Furthermore, operating at least part of the separation step d2) at a pressure substantially identical to the operating pressure of step b) facilitates the recycling of hydrogen contained in the gaseous effluent.

[0206] The separation step d2) can also be carried out at a pressure lower than the pressure of step b).

[0207] The separation step d2) may also include a (first) separation step at a pressure substantially equal to the operating pressure of step b), followed by at least one other separation step carried out at the same or lower temperature and pressure than each separation step of the preceding step d2).

[0208] Step d2) of separation can advantageously be implemented by any method known to those skilled in the art, such as, for example, the combination of one or more separators (flasks) and / or one or more stripping columns, these separators (flasks) and / or columns optionally being supplied with a stripping gas, for example, a hydrogen-rich gas stream. Step d2) of separation may, for example, include a stripping column for the acid water (also called a "sour water stripper" in Anglo-Saxon terminology) of the withdrawn aqueous effluent, an acid gas scrubbing column to purify the hydrogen-rich gas before recycling, and a stabilization column for the washed liquid effluent to remove dissolved gases.

[0209] Preferably, step d2) is carried out with a single separator (balloon). The separation step d2) is preferably carried out in at least one so-called high-pressure or medium-pressure, low-temperature separator ball, also known to those skilled in the art as CHPS (for "Cold High Pressure Separator" according to Anglo-Saxon terminology). Thus, this step d2) preferably uses a so-called "cold high-pressure separator", the pressure being substantially equal to the operating pressure of step b). Step e) of splitting (optional)

[0210] The process according to the invention may include a fractionation step of all or part, preferably all, of the hydrocarbon effluent from step d) when separation step d) is carried out after step c), and / or of all or part, preferably all, of the hydrotreated effluent from step c) when separation step d) is carried out between steps a) and c), to obtain at least one gas flow, a naphtha cut and at least one middle distillates cut.

[0211] The term "naphtha cut" means a hydrocarbon cut comprising compounds having a boiling point generally less than or equal to 175°C, in particular between 80 and 175°C.

[0212] The term "middle distillate cut" means a hydrocarbon cut comprising compounds having a boiling point generally above 175°C. The heavy cut may include middle distillates such as a diesel cut and / or a kerosene cut. It may also include heavier compounds.

[0213] Depending on the destination or use of the fractions from step e) of fractionation, a person skilled in the art will adjust the cut points in the stripping and / or distillation operations. For example, it may be necessary to adjust the endpoint of the naphtha cut to 150, 175 or 200°C, or even 250°C.

[0214] Step e) in particular allows the removal of gases dissolved in the hydrotreated liquid effluent, such as ammonia, hydrogen sulfide and light hydrocarbons having 1 to 4 carbon atoms.

[0215] The optional fractionation step e) is advantageously carried out at a pressure less than or equal to 1.0 MPa abs., preferably between 0.1 and 1.0 MPa abs.

[0216] According to one embodiment, step e) can be carried out in a section advantageously comprising at least one stripping column equipped with a reflux circuit including a reflux flask. Thus, the lighter compounds are carried to the top of the column and into the reflux circuit including a reflux flask in which a gas / liquid separation takes place. The gaseous phase, which includes the light hydrocarbons, is withdrawn from the reflux flask as a gas stream. The naphtha fraction is advantageously withdrawn from the reflux flask as a liquid stream. The middle distillates fraction is advantageously withdrawn from the bottom of the stripping column.

[0217] According to another embodiment, step e) can be carried out in a section comprising one or more separator tank(s). Advantageously, at least one low-pressure, low-temperature separator tank will be used to remove gases dissolved in the hydrotreated liquid effluent.

[0218] According to other embodiments, the fractionation step e) may employ a stripping column or a balloon separator followed by a distillation column or only a distillation column.

[0219] The naphtha cut and the middle distillates cut, possibly mixed, may be sent, in whole or in part, to a steam cracking unit, at the end of which olefins may be (re)formed to participate in polymer formation. Preferably, only a portion of said cuts is sent to a steam cracking unit; at least a fraction of the remaining portion is optionally recycled in at least one of the process steps and / or sent to a storage unit fuel, for example a naphtha storage unit, a diesel storage unit or a kerosene storage unit, derived from conventional petroleum feedstocks.

[0220] According to a preferred method, the naphtha cut, in whole or in part, is sent to a steam cracking unit, while the middle distillates cut is sent to a hydrocracking step f) and / or sent to a fuel storage unit.

[0221] In a particular embodiment, the optional fractionation step e) can provide, in addition to a gas stream, a naphtha cut (generally comprising compounds having a boiling point less than or equal to 175°C, preferably between 80 and 175°C), and a middle distillates cut (generally comprising compounds having a boiling point greater than 175°C and less than 385°C), and a heavy hydrocarbon cut (generally comprising compounds having a boiling point greater than or equal to 385°C).The naphtha cut can be sent, in whole or in part, to a steam cracking unit and / or to the naphtha storage unit from conventional petroleum feedstocks, or it can also be recycled; the middle distillate cut can also be sent, in whole or in part, either to a steam cracking unit, or to a diesel storage unit from conventional petroleum feedstocks, or to the hydrocracking stage f) when present, or it can also be recycled; the heavy cut can, for its part, be sent, at least in part, to a steam cracking unit, or be sent to the hydrocracking stage when present.

[0222] In another particular embodiment, the optional fractionation step e) can provide, in addition to a gas stream, a naphtha cut (generally comprising compounds having a boiling point less than or equal to 175°C, preferably between 80 and 175°C), and a kerosene cut (generally comprising compounds having a boiling point greater than 175°C and less than or equal to 280°C), a diesel cut (generally comprising compounds having a boiling point greater than 280°C and less than 385°C) and a heavy hydrocarbon cut (generally comprising compounds having a boiling point greater than or equal to 385°C). The naphtha cut, the kerosene cut and / or the diesel cut can be, in whole or in part, either sent to a steam cracking unit, or respectively to a naphtha, kerosene or diesel pool from conventional petroleum feedstocks, or recycled.Diesel and / or kerosene fractions can also be sent to the hydrocracking stage (f) when available. Heavy fractions, on the other hand, can be sent, at least in part, to a steam cracking unit, or sent to the hydrocracking stage (f) when available.

[0223] In another particular embodiment, the naphtha cut from step e) is fractionated into a heavy naphtha cut (generally comprising compounds having a boiling point between 80 and 175°C) and a light naphtha cut (generally comprising (relative to compounds having a boiling point below 80°C), at least a portion of said heavy naphtha cut being sent to an aromatic complex comprising at least one naphtha reforming step for the production of aromatic compounds. According to this embodiment, at least a portion of the light naphtha cut is sent to the steam cracking step (g) described below.

[0224] When the content of tire pyrolysis oil is significant in the feed (i.e., greater than 50% of the feed weight), the naphtha fraction obtained from the process according to the invention can also be sent to a catalytic reforming unit. Indeed, the high aromatic content in tire pyrolysis oils makes it possible to obtain a highly aromatic and naphthenic naphtha fraction that exhibits a high octane number (high RON / MON (RON = Research Octane Number and Motor Octane Number according to Anglo-Saxon terminology)).

[0225] The gaseous effluent(s) from step e) of fractionation may be subjected to further purification and separation in order to recover at least light hydrocarbons, in particular ethane, propane and butane, which may advantageously be sent separately or mixed to one or more furnaces of step g) of steam cracking so as to increase the overall olefin yield. Step f) of hydrocracking (optional)

[0226] According to one variant, the process of the invention may include a hydrocracking step f) with at least a portion of said effluent from step d) when separation step d) is carried out after step c), and / or with at least a portion of the hydrotreated effluent from step c) when separation step d) is carried out between steps b) and c), and / or with at least a portion of the middle distillate cut from fractionation step e).

[0227] Advantageously, step f) implements hydrocracking reactions well known to those skilled in the art, and more particularly allows the conversion of heavy compounds, for example compounds having a boiling point above 175°C, into compounds having a boiling point less than or equal to 175°C. Other reactions, such as the hydrogenation of olefins, aromatics, hydrodemetallation, hydrodesulfurization, hydrodeazotation, etc., can be carried out.

[0228] Compounds with a boiling point above 175°C contain, compared to lighter compounds, more naphthenic, naphtheno-aromatic, and aromatic compounds, thus leading to a higher C / H ratio. This high ratio causes coking in the steam cracker, necessitating steam cracking furnaces dedicated to this cut. When it is desired to minimize the yield of these heavy compounds (middle distillate cut) and maximize the yield of light compounds (naphtha cut), these compounds can be converted, at least partially, into light compounds by hydrocracking, a cut generally preferred for a steam cracking unit.

[0229] Thus, the process of the invention may comprise a hydrocracking step (f) carried out in a hydrocracking reaction section, employing at least one fixed-bed reactor having n catalytic beds, n being an integer greater than or equal to 1, each comprising at least one hydrocracking catalyst, said hydrocracking reaction section being fed by at least a portion of said effluent from step (d) when separation step (d) is carried out after step (c), and / or by at least a portion of the hydrotreated effluent from step (c) when separation step (d) is carried out between steps (b) and (c), and / or by at least a portion of the middle distillate cut from fractionation step (e) and a gas stream comprising hydrogen, said hydrocracking reaction section being carried out at an average temperature between 250 and 450°C, a partial pressure of hydrogen between 1.5 and 20.0 MPa abs.and an hourly volumetric velocity between 0.1 and 10.0 h⁻¹ to obtain a first hydrocracked effluent.

[0230] Thus, said hydrocracking reaction section is advantageously implemented at an average temperature between 250 and 480°C, preferably between 320 and 450°C, at a partial pressure of hydrogen between 1.5 and 20.0 MPa abs., preferably between 3 and 18.0 MPa abs., and at a volumetric rate per hour (WH) between 0.1 and 10.0 h⁻¹, preferably between 0.1 and 5.0 h⁻¹, preferably between 0.2 and 4 h⁻¹. The hydrogen coverage in step f) is advantageously between 80 and 2000 Nm³ of hydrogen per m³ of fresh feedstock supplying step f), and preferably between 200 and 1800 Nm³ of hydrogen per m³ of fresh feedstock supplying step f). The definitions of mean temperature (WABT), WH and hydrogen cover correspond to those described above.

[0231] Advantageously, said hydrocracking reaction section is implemented at a pressure equivalent to that used in the reaction section of step b) of hydrogenation or step c) of hydrotreating.

[0232] Advantageously, said step f) is implemented in a hydrocracking reaction section comprising at least one, preferably between one and five, fixed-bed reactor(s) having n catalytic beds, n being an integer greater than or equal to one, preferably between one and ten, preferably between two and five, said bed(s) each comprising at least one, and preferably not more than ten, hydrocracking catalysts.

[0233] The hydrocracking reaction section employing at least one fixed-bed reactor can operate with downward or upward flow of gas and liquid.

[0234] The hydrocracked effluent can at least partly be recycled in steps b), c), d) or e).

[0235] The hydrocracking step can be carried out in one step (step f) or two steps (steps f and f'). When carried out in two steps, the effluent is separated from the first hydrocracking step f) allowing to obtain a hydrocarbon cut comprising compounds having a boiling point above 175°C (middle distillate cut), which is introduced into the second hydrocracking step f') comprising a second dedicated hydrocracking reaction section, different from the first hydrocracking reaction section f). This configuration is particularly suitable when it is desired to produce only a naphtha cut.

[0236] The second hydrocracking step f') is carried out in a hydrocracking reaction section, employing at least one fixed-bed reactor having n catalytic beds, n being an integer greater than or equal to 1, each comprising at least one hydrocracking catalyst, said hydrocracking reaction section being fed with at least a portion of the first hydrocracking effluent from the first hydrocracking step f) and a gas stream comprising hydrogen, said hydrocracking reaction section being carried out at an average temperature between 250 and 450°C, a partial pressure of hydrogen between 1.5 and 20.0 MPa abs., and a volumetric flow rate between 0.1 and 10.0 h⁻¹, to obtain a second hydrocracking effluent. The preferred operating conditions and catalysts used in the second hydrocracking step are those described for the first hydrocracking step.The operating conditions and catalysts used in the two hydrocracking stages may be identical or different.

[0237] Said second hydrocracking step is preferably carried out in a hydrocracking reaction section comprising at least one, preferably between one and five, fixed bed reactor(s) having n catalytic beds, n being an integer greater than or equal to one, preferably between one and ten, preferably between two and five, said bed(s) each comprising at least one, and preferably not more than ten, hydrocracking catalyst(s).

[0238] These operating conditions used in the hydrocracking step(s) generally allow for conversions per pass to products having at least 80% by volume of compounds with boiling points of 175°C or lower, preferably lower than 160°C and preferably lower than 150°C, and greater than 15% by weight, and even more preferably between 20 and 95% by weight. When the process is carried out in two hydrocracking steps, the conversion per pass in the second step is kept moderate in order to maximize selectivity for naphtha cut compounds (having a boiling point of 175°C or lower, in particular between 80 and 175°C or lower). The conversion per pass is limited by the use of a high recycle ratio on the loop of the second hydrocracking step.This rate is defined as the ratio between the feed rate of stage f') and the charge rate of stage b), preferably this ratio is . between 0.2 and 4, preferably between 0.5 and 2.5.

[0239] The hydrocracked effluent from the second hydrocracking step f') can at least partly be recycled in steps b), c), d) or e).

[0240] The hydrocracking step(s) do not necessarily allow the conversion of all hydrocarbon compounds in the middle distillates cut into hydrocarbon compounds with a boiling point of 175°C or lower (naphtha cut). After the fractionation step e), a more or less significant proportion of compounds with a boiling point above 175°C may therefore remain. At least part of this unconverted cut can be introduced into a second hydrocracking step f'). Another part can be purged. Depending on the process operating conditions, this purge can be between 0 and 10% by weight of the cut containing compounds with a boiling point above 175°C relative to the incoming feed, and preferably between 0.5% and 5% by weight.

[0241] According to the invention, the hydrocracking step(s) operate in the presence of at least one hydrocracking catalyst.

[0242] The hydrocracking catalyst(s) used in the hydrocracking step(s) are conventional hydrocracking catalysts known to those skilled in the art, of a bifunctional type combining an acid function with a hydro-dehydrogenating function and optionally at least one binding matrix. The acid function is provided by large surface area supports (generally 150 to 800 m² / g) exhibiting surface acidity, such as halogenated aluminas (particularly chlorinated or fluorinated), combinations of boron and aluminum oxides, amorphous silica-aluminas, and zeolites. The hydro-dehydrogenating function is provided by at least one metal from group VIB of the periodic table and / or at least one metal from group VIII.

[0243] Preferably, the hydrocracking catalyst(s) comprise a hydro-dehydrogenating function including at least one metal from Group VIII selected from iron, cobalt, nickel, ruthenium, rhodium, palladium, and platinum, and preferably from cobalt and nickel. Preferably, said catalyst(s) also comprise at least one metal from Group VIB selected from chromium, molybdenum, and tungsten, alone or in a mixture, and preferably from molybdenum and tungsten. NiMo, NiMoW, and NiW type hydro-dehydrogenating functions are preferred.

[0244] Preferably, the content of Group VIII metal in the hydrocracking catalyst(s) is advantageously between 0.5 and 15 wt% and preferably between 1 and 10 wt%, the percentages being expressed as a wt% of oxides relative to the total weight of the catalyst. When the metal is cobalt or nickel, the metal content is expressed as CoO and NiO, respectively.

[0245] Preferably, the content of group VIB metal in the hydrocracking catalyst(s) is advantageously between 5 and 35 wt%, and preferably between 10 and 30 wt%, the percentages being expressed as a wt% of oxides relative to the total weight of the catalyst. When the metal is molybdenum or tungsten, the metal content is expressed as MoO3 and WO3 respectively.

[0246] The hydrocracking catalyst(s) may also optionally include at least one promoting element deposited on the catalyst and selected from the group formed by phosphorus, boron and silicon, optionally at least one element from group VIIA (chlorine, fluorine preferred), optionally at least one element from group VIIB (manganese preferred), and optionally at least one element from group VB (niobium preferred).

[0247] Preferably, the hydrocracking catalyst(s) comprise at least one amorphous or poorly crystallized porous mineral matrix of the oxide type selected from aluminas, silicas, silica-aluminas, aluminates, alumina-boron oxide, magnesia, silica-magnesia, zirconia, titanium oxide, clay, alone or in mixture, and preferably aluminas or silica-aluminas, alone or in mixture.

[0248] Preferably, the silica-alumina contains more than 50% by weight of alumina, preferably more than 60% by weight of alumina.

[0249] Preferably, the hydrocracking catalyst(s) may also include a zeolite selected from the Y zeolites, preferably from the US Y zeolites, alone or in combination with other zeolites from the beta zeolites, ZSM-12, IZM-2, ZSM-22, ZSM-23, SAPO-11, ZSM-48, ZBM-30, alone or in mixtures. Preferably, the zeolite is the USY zeolite alone.

[0250] In the case where said catalyst includes a zeolite, the zeolite content in the hydrocracking catalyst(s) is advantageously between 0.1 and 80% by weight, preferably between 3 and 70% by weight, the percentages being expressed as a percentage of zeolite relative to the total weight of the catalyst.

[0251] A preferred catalyst comprises, and preferably consists of, at least one metal from group VIB and optionally at least one non-noble metal from group VIII, at least one promoting element, preferably phosphorus, at least one zeolite Y and at least one alumina binder.

[0252] An even more preferred catalyst comprises, and is preferably made up of, nickel, molybdenum, phosphorus, a USY zeolite, and possibly also a beta zeolite, and alumina.

[0253] Another preferred catalyst comprises, and is preferably made up of, nickel, tungsten, alumina and silica-alumina.

[0254] Another preferred catalyst comprises, and is preferably made up of, nickel, tungsten, USY zeolite, alumina and silica-alumina.

[0255] Said hydrocracking catalyst is for example in the form of extrudates.

[0256] In one embodiment, the hydrocracking catalyst used in the second hydrocracking step comprises a hydro-dehydrogenating function including at least one Group VIII noble metal selected from palladium and platinum, alone or in a mixture. The Group VIII noble metal content is advantageously between 0.01 and 5 wt% and preferably between 0.05 and 3 wt%, the percentages being expressed as a wt% of oxides (PtO or PdO) relative to the total wt% of the catalyst.

[0257] According to another aspect of the invention, the hydrocracking catalysts as described above further comprise one or more organic compounds containing oxygen and / or nitrogen and / or sulfur as described above (additized catalyst).

[0258] Said hydrocarbon effluent or hydrocarbon fraction(s) thus obtained by treatment according to the process of the invention, have a composition compatible with the specifications of an inlet feed for a steam cracking unit. In particular, the composition of the hydrocarbon effluent or hydrocarbon fraction(s) resulting from the process is preferably such that: - the total metallic content is less than or equal to 10.0 ppm by weight, preferably less than or equal to 2.0 ppm by weight, preferably less than or equal to 1.0 ppm by weight and preferably less than or equal to 0.8 ppm by weight, with: a silicon (Si) content of less than or equal to 5.0 ppm by weight, preferably less than or equal to 1 ppm by weight, and preferably less than or equal to 0.6 ppm by weight and an iron (Fe) content less than or equal to 200 ppb by weight, - the sulfur content is less than or equal to 500 ppm by weight, preferably less than or equal to 200 ppm by weight, - the nitrogen content is less than or equal to 100 ppm by weight, preferably less than or equal to 50 ppm by weight, preferably less than or equal to 10 ppm by weight, and particularly preferably less than or equal to 5 ppm by weight - the total chlorine content is less than or equal to 5.0 ppm by weight, preferably less than 1.0 ppm by weight, - the content of olefinic compounds (mono- and di-olefins) is less than or equal to 5.0% by weight, preferably less than or equal to 2.0% by weight, preferably less than or equal to 0.1% by weight. - the mercury content is less than or equal to 5 ppb by weight, preferably less than 3 ppb by weight.

[0259] The contents are given as relative weight concentrations, percentage (%) by weight, part(s) per million (ppm) by weight or part(s) per billion (ppb) by weight, relative to the total weight of the stream considered.

[0260] The process according to the invention therefore makes it possible to treat pyrolysis oils to obtain at least one effluent which can be injected, in whole or in part, into at least one steam cracking unit. Step g) of steam cracking (optional)

[0261] At least part of the effluent from step d) when separation step d) is carried out after step c), and / or at least part of the hydrotreated effluent from step c) when separation step d) is carried out between steps b) and c) and / or at least one of the liquid hydrocarbon cuts from optional fractionation step e), may be sent in whole or in part to a steam cracking step g).

[0262] Advantageously, the gaseous effluent(s) from step d) of separation and / or e) of fractionation and containing ethane, propane and butane, may, in whole or in part, also be sent to step g) of steam cracking.

[0263] Said steam cracking step (g) is advantageously carried out in at least one pyrolysis furnace at a temperature between 700 and 900°C, preferably between 750 and 850°C, and at a pressure between 0.05 and 0.3 MPa relative. The residence time of the hydrocarbon compounds is generally less than or equal to 1.0 second (denoted s), preferably between 0.1 and 0.5 s. Advantageously, steam is introduced upstream of the optional steam cracking step (g) and after the separation (or fractionation). The quantity of water introduced, advantageously in the form of steam, is advantageously between 0.3 and 3.0 kg of water per kg of hydrocarbon compounds entering step (g). Preferably, the optional step g) is carried out in several pyrolysis ovens in parallel in order to adapt the operating conditions to the different flows feeding step g), in particular from step e), and also to manage the decoking times of the tubes.A furnace comprises one or more tubes arranged in parallel. A furnace can also refer to a group of furnaces operating in parallel. For example, a furnace might be dedicated to cracking the middle distillate cut.

[0264] The effluents from the various steam cracking furnaces are generally recombined before separation to form a single effluent. It is understood that step g) of steam cracking includes the steam cracking furnaces but also the substeps associated with steam cracking that are well known to those skilled in the art. These substeps may include, in particular, heat exchangers, columns and catalytic reactors, and recirculation to the furnaces. A column generally allows the effluent to be fractionated in order to recover at least a light fraction comprising hydrogen and compounds having 2 to 5 carbon atoms, and a fraction comprising pyrolysis gasoline, and possibly a heavier fraction. Columns allow for The process separates the different components of the light fractionation fraction to recover at least one ethylene-rich cut (C2 cut), one propylene-rich cut (C3 cut), and possibly one butene-rich cut (C4 cut). Catalytic reactors are used to hydrogenate the C2, C3, and even C4 cuts, as well as pyrolysis gasoline. Saturated compounds, particularly those with 2 to 4 carbon atoms, are advantageously recycled to steam cracking furnaces to increase overall olefin yields.

[0265] This steam cracking step (g) yields at least one effluent containing olefins comprising 2, 3, and / or 4 carbon atoms (i.e., C2, C3, and / or C4 olefins) at satisfactory levels, in particular greater than or equal to 30 wt%, especially greater than or equal to 40 wt%, or even greater than or equal to 50 wt% of total olefins comprising 2, 3, and 4 carbon atoms relative to the weight of the steam cracking effluent considered. These C2, C3, and C4 olefins can then be advantageously used as polyolefin monomers. (Optional) heavy metal adsorption step

[0266] Any gaseous effluent and / or any liquid effluent from at least one of the separation steps d) or from the fractionation step e) may be subjected to an optional heavy metal adsorption step.

[0267] The optional adsorption step makes it possible to eliminate or reduce the quantity of metallic impurities, in particular the quantity of heavy metals such as arsenic, zinc, lead, and especially mercury, which may be present in said gaseous and liquid effluents. The metallic impurities, and in particular heavy metals, are present in the feedstock. Certain impurities, particularly those based on mercury, can be transformed in one of the steps of the process according to the invention. Their transformed form is easier to trap. Their elimination or reduction may be necessary, in particular, when at least a portion of said gaseous and liquid effluents is intended to be sent, either directly or after undergoing one or more optional additional steps such as the fractionation step (e), to a step having strict specifications for metallic impurities, such as a steam cracking step.

[0268] Thus, an optional step of adsorption of a gaseous effluent and / or a hydrocarbon effluent from the process according to the invention is advantageously carried out in particular when at least one of these effluents or the feed includes respectively more than 20 ppb by weight, in particular more than 15 ppb by weight of metallic elements of heavy metals (As, Zn, Pb, Hg, ...), and in particular when at least one of these effluents or the feed includes respectively more than 10 ppb by weight of mercury, more particularly more than 15 ppb by weight of mercury.

[0269] Said optional adsorption step is advantageously implemented at a time temperature between 20 and 250°C, preferably between 40 and 200°C, and at a pressure between 0.15 and 10.0 MPa abs, preferably between 0.2 and 1.0 MPa abs.

[0270] Said optional adsorption step can be implemented by any adsorbent known to those skilled in the art that allows the quantity of such contaminants to be reduced.

[0271] According to one variant, said optional adsorption step is implemented in an adsorption section operated in the presence of at least one adsorbent comprising a porous support, and optionally at least one active phase which may be sulfur-based in elemental form, or in the form of metallic sulfide or metallic oxide, or even in metallic form in elemental form.

[0272] The porous support may be chosen indifferently from the families of aluminas, silica-aluminas, silicas, zeolites and / or activated carbons. Advantageously, the porous support is alumina-based.

[0273] Said adsorption section may comprise one or more adsorption columns. When the adsorption section comprises two adsorption columns, one operating mode may be a so-called "swing" mode, in which one of the columns is in operation, while the other column is in reserve. Another operating mode is to have at least two columns operating in series in a switchable mode.

[0274] Preferably, said adsorption section comprises an adsorption column for the gaseous effluent(s) and an adsorption column for the liquid effluent(s). ANALYTICAL METHODS USED

[0275] The analytical methods and / or standards used to determine the characteristics of the various flows, in particular the load to be treated and the effluents, are known to those skilled in the art. They are listed below for information purposes. Other methods considered equivalent may also be used, including equivalent IP, EN, or ISO methods:

[0276] [Tables 1] Description Methods Density @15°C ASTM D4052 Sulfur Content ISO 20846 Nitrogen Content ASTM D4629 Acid Value ASTM D664 Bromine Value ASTM DI 159 Maleic Anhydride Value MAV Method (1) Oxygen Content Combustion + Infrared Paraffin Content UOP990-11 Naphthenes and Olefins Content UOP990-11 Aromatics Content UOP990-11 Halogen Content ASTM D7359 Chlorine Content ASTM D7536 Metal Content: ASTM D5185 P Fe Si Na B Simulated Distillation ASTM D2887

[0277] (1) MAV method described in the article: C. Lôpez-Garcla et al., Near Infrared Mo- nitoring of Low Conjugated Diolefins Content in Hydrotreated FCC Gasoline Streams, Oil & Gas Science and Technology - Rev. IFP, Vol. 62 (2007), No. 1, pp. 57-68. LIST OF FIGURES

[0278] Mention of the elements referenced in Figures 1 to 4 allows for a better understanding of the invention, without the latter being limited to the particular embodiments illustrated in Figures 1 to 4. The different embodiments presented can be used alone or in combination with each other, without limitation of combination.

[0279] Figures 1 and 2 refer to the embodiment in which step d) of se- The preparation is carried out after step c) of hydrotreatment.

[0280] Figures 3 and 4 refer to the embodiment in which the separation step d) is carried out between the hydrogenation step b) and the hydrotreating step c). [Fig 1]

[0281] Figure 1 shows a diagram of a particular embodiment of the process of the present invention, comprising:

[0282] - a step a) of selective hydrogenation (optional) of a feed 1 comprising at less 5% weight of a tire pyrolysis oil relative to the total weight of the load, said tire pyrolysis oil having a sulfur content between 2000 and 10000 ppm weight relative to the total weight of the oil, in the presence of a hydrogen-rich gas 2, to obtain a selectively hydrogenated effluent 3;

[0283] - a step b) of hydrogenating said selectively hydrogenated effluent 3 from step a) in the presence of a hydrogen-rich gas 4 and possibly an amine supplied by the stream 5 and possibly a sulfurating agent by the stream 6, to obtain a hydrogenated effluent 7;

[0284] - a step c) hydrotreatment fed by the hydrogenated effluent 7 from step b) hydrogenation and by a flow of a hydrogen-rich gas 8, to obtain a hydrotreated effluent 9;

[0285] - a separation step d) fed by the effluent 9 from step c) hydrotreating and in the presence of an aqueous solution 12 to obtain at least one gaseous effluent 13, one aqueous effluent 14 and one hydrocarbon effluent 15. [Fig 2]

[0286] [Fig.2] represents the diagram of another particular embodiment of the process of the present invention which is based on the diagram of [Fig.1]. This diagram includes a step d) carried out in two steps, steps d1) and d2), then a step e) of fractionation and a step f) of hydrocracking in addition.

[0287] Step a) of elective hydrogenation (optional), step b) of hydrogenation, and step c) of hydrotreating are carried out as described in [Fig. 1]. Step d) of separation, carried out in two stages, includes in particular:

[0288] - a step d1) of separation of the hydrotreated effluent 9 carried out at high pressure and high temperature (HHPS) to obtain at least a first gaseous effluent 10 and a liquid effluent 11 of which part 1a can be recycled upstream of step b) or upstream of step a) (not shown),

[0289] - a separation step d2) carried out at high pressure and low temperature (HPLS) and supplied by the gaseous effluent 10 and the other part of the liquid effluent 11b from step dl) and an aqueous solution 12 and allowing to obtain at least one gaseous effluent 13 comprising hydrogen, an aqueous effluent 14 containing salts dissolved and dissolved H2S and NH3, and a hydrocarbon effluent 15;

[0290] Optionally, a step e) of fractionation of the effluent 15 is carried out to obtain at least a gaseous effluent 16, a naphtha cut 17 and a middle distillates cut 18.

[0291] Following step e), a portion of the naphtha 17 cut can be sent to a steam cracking process (not shown). Another portion of the naphtha 17 cut can feed into step a) selective hydrogenation, step b) hydrogenation, and / or step c) hydrotreating (recycling not shown).

[0292] In [Fig.2], at least a portion of the middle distillate cut 18 from step e) feeds a hydrocracking step f) which is carried out in at least one fixed bed reactor comprising at least one hydrocracking catalyst and is supplied with hydrogen 19. The hydrocraced effluent 20 can be recycled between the separation steps d1) and d2) or upstream of the separation step d) (not shown). [Fig 3]

[0293] Figure 3 shows a diagram of a particular embodiment of the process of the present invention, comprising:

[0294] - a step a) of selective hydrogenation (optional) of a feed 1 comprising at less 5% weight of a tire pyrolysis oil relative to the total weight of the load, said tire pyrolysis oil having a sulfur content between 2000 and 10000 ppm weight relative to the total weight of the oil, in the presence of a hydrogen-rich gas 2, to obtain a selectively hydrogenated effluent 3;

[0295] - a step b) of hydrogenating said selectively hydrogenated effluent 3 from step a) in the presence of a hydrogen-rich gas 4 and possibly an amine supplied by the stream 5 and possibly a sulfurating agent by the stream 6, to obtain a hydrogenated effluent 7;

[0296] - a separation step d) fed by the hydrogenated effluent 7 from step b) hydrogenation and in the presence of an aqueous solution 12 to obtain at least a gaseous effluent 13, an aqueous effluent 14 and a washed hydrocarbon effluent 23 freed in particular from chlorine impurities.

[0297] - a step c) hydrotreatment fed by the washed hydrogenated effluent 23 cleared including chlorine impurities from separation step d) and by a flow of hydrogen-rich gas 8, to obtain a hydrotreated hydrocarbon effluent 15. [Fig 4]

[0298] Figure 4 shows a diagram of another particular embodiment of the process of the present invention which is based on the diagram of Figure 3. This diagram includes a step d) carried out in two steps, steps d1 and d2), then a fractionation step e) and a hydrocracking step f) in addition.

[0299] Step a) selective hydrogenation (optional) and step b) hydrogenation are carried out as described in [Fig. 3]. Step d) separation, carried out in two stages, includes in particular:

[0300] - a step d1) of separation of the hydrogenated effluent 7 carried out at high pressure and high temperature (HHPS) to obtain at least a first gaseous effluent 21 and a liquid effluent 22 of which a part 22a can be recycled upstream of step b) or upstream of step a) (not shown),

[0301] - a separation step d2) carried out at high pressure and low temperature (HPLS) and supplied by the gaseous effluent 21 and the other part of the liquid effluent 22b from step dl) and an aqueous solution 12 and enabling the production of at least a second gaseous effluent 13 comprising hydrogen, an aqueous effluent 14 containing dissolved salts and dissolved H2S and NH3, and a washed hydrocarbon effluent 23;

[0302] - a step c) hydrotreatment fed by the washed hydrocarbon effluent 23 de cleansed in particular of chlorine impurities from separation step d) and by a flow of hydrogen-rich gas 8, to obtain a hydrotreated hydrocarbon effluent 15.

[0303] Optionally, a step e) of fractionation of the hydrotreated hydrocarbon effluent 15 is carried out, allowing at least one gaseous effluent 16, one naphtha cut 17 and one middle distillates cut 18 to be obtained.

[0304] Following step e), a portion of the naphtha 17 cut can be sent to a steam cracking process (not shown). Another portion of the naphtha 17 cut can feed into step a) selective hydrogenation, step b) hydrogenation, and / or step c) hydrotreating (recycling not shown).

[0305] In [Fig.4], at least a portion of the middle distillate cut 18 from step e) feeds a hydrocracking step f) which is carried out in at least one fixed bed reactor comprising at least one hydrocracking catalyst and is supplied with hydrogen 19. The hydrocraced effluent 20 can be recycled between the separation steps d1) and d2) or upstream of the separation step d) (not shown).

[0306] Only the main stages, with the principal flows, are shown in Figures 1 to 4, to facilitate a better understanding of the invention. It is understood that all the equipment necessary for operation is present (tanks, pumps, heat exchangers, furnaces, columns, etc.), even if not shown. It is also understood that hydrogen-rich gas flows (make-up or recycle), as described above, can be injected at the inlet of each reactor or catalytic bed or between two reactors or two catalytic beds. Methods well known to those skilled in the art for hydrogen purification and recycling can also be implemented. EXAMPLES Example 1 (in accordance with the invention)

[0307] The feed treated in the process with a flow rate of 10000 kg / h (10 T / h) is a tire pyrolysis oil (i.e. comprising 100% by weight of said tire pyrolysis oil) having the characteristics indicated in Table 2.

[0308] Table 2: Load characteristics

[0309] [Tables2] Property Method Unit Tire Pyrolysis Oil Density at 15°C NF EN ISO 12185 g / cm3 0.907 Bromine Index ASTM DI 159 g / 100g 73 MAV IFPEN 9407 mg / g 34 S ASTM D5453 mg / kg 4892 N ASTM D4629 mg / kg 2720 Cl ASTM D7536 mg / kg 6 Si ASTM D5185 mg / kg 10 Simulated Distillation ASTM D2887 Initial boiling point (0.50%) °C 87 10% °C 173 30% °c 243 50% °c 302 70% °c 363 90% °c 440 Final boiling point (99.50%) °c 551

[0310] The feedstock is mixed with a liquid recycle, i.e., a portion of the liquid effluent from a hot tank in separation step d), in a mass ratio of 80 / 20, i.e., 40 T / h of liquid recycle for 10 T / h of feedstock. The resulting mixture is subjected to hydrogenation step b) in a fixed-bed reactor in the presence of hydrogen and a NiMo-alumina hydrogenation catalyst under the conditions specified in Table 3.

[0311] Table 3: Conditions for step b) of hydrogenation

[0312] [Tables3] Reactor inlet temperature °C 290 Reactor outlet temperature °C 320 Average temperature (WABT) °C 305 Partial pressure of hydrogen MPa abs 5.7 H2 / HC (hydrogen volume coverage relative to feed volume) NmVm3 300 WH (fresh feed volume flow rate / catalyst volume) h1 0.8

[0313] The conditions indicated in Table 3 correspond to cycle start conditions.

[0314] At the end of step b) of hydrogenation, the conversion rates (= (initial concentration - final concentration) / initial concentration) observed are shown in Table 4.

[0315] Table 4: Species conversions during step b) of hydrogenation

[0316] [Tables4] Diolefin conversion rate % >80 Olefin conversion rate % >70 Silicon retention % >85

[0317] The effluent from step b) of hydrogenation is directly subjected, without separation, to a step b) of hydrotreatment carried out in a fixed bed and in the presence of hydrogen and a NiMo on alumina type hydrotreatment catalyst under the conditions presented in Table 5.

[0318] Table 5: Conditions of step c) of hydrotreatment

[0319] [Tables5] Average Water Treatment Temperature (WABT) °C 325 Partial Pressure of Hydrogen MPa abs 5.5 Partial Pressure of Hydrogen Sulfide MPa abs 0.019 H2 / HC (Volume Coverage of Hydrogen relative to Feed Volume) NmVm3 400 WH (Volume Flow Rate of Feed / Volume of Catalysts) h1 0.5

[0320] The conditions indicated in Table 5 correspond to start conditions cycle.

[0321] The effluent from hydrotreatment step c) is subjected to a separation step d) comprising a separation step d1) and a separation step d2). The effluent from hydrotreatment step c) is subjected to separation step d1) which includes a high-pressure separator tank operated at 300°C and 5.2 MPa abs. The fraction obtained at the bottom of the high-pressure separator tank is used via a pump to recycle a portion of the effluent to the inlet of hydrogenation step b). The fraction obtained at the top of the high-pressure separator tank is mixed with the portion obtained at the bottom of the high-pressure separator tank that is not recycled to the inlet of hydrogenation step b). This hydrocarbon mixture is subjected to separation step d2, in which a stream of water is injected.The hydrocarbon mixture and the water stream are then treated in an acid gas scrubbing column and separator vessels to obtain a gas fraction, an aqueous effluent containing salts, and a liquid effluent. The yields and quality of the different fractions obtained after separation are shown in Table 6 (the yields correspond to the ratios of the mass quantities of the different products obtained to the mass of feed upstream of step b), expressed as a percentage and noted as % w / w).

[0322] Table 6: Yields and quality of the different products obtained after separation

[0323] [Tables] Yield Gas fraction (NH3 + H2S + C1-C4) % w / w 1.43 Yield Liquid fraction % w / w 100.12 Nitrogen content of liquid fraction (ASTM D4629) mg / kg 7 Sulfur content of liquid fraction (ASTM D5453) mg / kg 33 Chlorine content of liquid fraction (ASTM D7536) mg / kg 3 Silicon content of liquid fraction (ASTM D5185) mg / kg < 1

[0324] All or part of the liquid fraction obtained can then be valorized in a steam cracking step in order to form olefins which can be polymerized in order to form recycled plastics.

[0325] The tire pyrolysis oil feed contains a large amount of sulfur (4892 ppm by weight). This sulfur, which is in the form of sulfur molecules, is hydrogenated in the reaction section and transformed into hydrogen sulfide (H2S). This H2S, under The partial pressure of H₂S (ppH₂S) of 0.019 MPa abs at the outlet of the hydrotreating reactor contributes to maintaining the sulfide phase of the NiMo catalysts on alumina and therefore to the catalyst activity. Consequently, the loss of catalytic activity in step c) of hydrotreating is low (< 1°C less) and it is not necessary to inject hydrogen sulfide or a sulfur compound such as DMDS to maintain catalytic activity. Example 2 (according to the invention)

[0326] The feed treated in the process with a flow rate of 10000 kg / h (10 T / h) is a 6 / 94 w / w mixture of tire pyrolysis oil of Example 1 and plastic pyrolysis oil (i.e. comprising 6 wt% of said tire pyrolysis oil and 94 wt% of said plastic pyrolysis oil) having the characteristics indicated in Table 7.

[0327] Table 7: Load characteristics

[0328] [Tables?] Property Method NF EN ISO 12185 Unit Mixture 6 / 94 w / w Tyre pyrolysis oil and plastic pyrolysis oil Density at 15°C g / cm3 0.804 Bromine Number ASTM DI 159 g / 100g 50 MAV IFPEN 9407 mg / g 12 S ASTM D5453 mg / kg 355 N ASTM D4629 mg / kg 965 Cl ASTM D7536 mg / kg 88 Si ASTM D5185 mg / kg 19 Simulated Distillation ASTM D2887 Initial boiling point (0.50%) °C 60 10% °C 134 30% °C 198 50% °C 267 70% °C 330 90% °C 397 Final boiling point (99.50%) °C 561

[0329] The feedstock is mixed with a liquid recycle, i.e., a portion of the liquid effluent from a hot tank in separation step d), in a mass ratio of 80 / 20, i.e., 40 T / h of liquid recycle for 10 T / h of feedstock. The resulting mixture is subjected to hydrogenation step b) in a fixed-bed reactor in the presence of hydrogen and a NiMo-alumina hydrogenation catalyst under the conditions specified in Table 8.

[0330] Table 8: Conditions for step b) of hydrogenation

[0331] [Tables8] Reactor inlet temperature °C 290 Reactor outlet temperature °C 320 Average temperature (WABT) °C 305 Partial pressure of hydrogen MPa abs 5.7 H2 / HC (hydrogen volume coverage relative to feed volume) NmVm3 300 WH (feed volume flow rate / catalyst volume) h1 0.8

[0332] The conditions indicated in Table 8 correspond to cycle start conditions.

[0333] At the end of step b) of hydrogenation, the conversion rates (= (initial concentration - final concentration) / initial concentration) observed are shown in Table 9.

[0334] Table 9: Species conversions during step b) of hydrogenation

[0335] [Tables9] Diolefin conversion rate % >85 Olefin conversion rate % >75 Silicon retention % >90

[0336] The effluent from step b) of hydrogenation is directly subjected, without separation, to a step b) of hydrotreatment carried out in a fixed bed and in the presence of hydrogen and a NiMo on alumina type hydrotreatment catalyst under the conditions presented in Table 10.

[0337] Table 10: Conditions of step c) of hydrotreatment

[0338] [TableauxlO] Average Water Treatment Temperature (WABT) °C 325 Partial Pressure of Hydrogen MPa abs 5.5 Partial Pressure of Hydrogen Sulfide MPa abs 0.0027 H2 / HC (Volume Coverage of Hydrogen relative to Feed Volume) NmVm3 400 WH (Volume Flow Rate of Feed / Volume of Catalysts) h1 0.5

[0339] The conditions indicated in Table 10 correspond to cycle start conditions.

[0340] The effluent from hydrotreatment step c) is subjected to a separation step d) comprising a separation step d1) and a separation step d2). The effluent from hydrotreatment step c) is subjected to separation step d1) which includes a high-pressure separator tank operated at 300°C and 5.2 MPa abs. The fraction obtained at the bottom of the high-pressure separator tank is used via a pump to recycle a portion of the effluent to the inlet of hydrogenation step b). The fraction obtained at the top of the high-pressure separator tank is mixed with the portion obtained at the bottom of the high-pressure separator tank that is not recycled to the inlet of hydrogenation step b). This hydrocarbon mixture is subjected to separation step d2, in which a stream of water is injected.The hydrocarbon mixture and the water stream are then treated in an acid gas scrubbing column and separator vessels to obtain a gas fraction, an aqueous effluent including salts, and a liquid effluent. The yields and quality of the different fractions obtained after separation are shown in Table 11 (the yields correspond to the ratios of the mass quantities of the different products obtained to the mass of feed upstream of step b), expressed as a percentage and noted as % w / w).

[0341] Table 11: Yields and quality of the different products obtained after separation

[0342] [Table 11] Yield Gas fraction (NH3 + H2S + C1-C4) % w / w 1.19 Yield Liquid fraction % w / w 99.87 Nitrogen content of liquid fraction (ASTM D4629) mg / kg 3 Sulfur content of liquid fraction (ASTM D5453) mg / kg 8 Chlorine content of liquid fraction (ASTM D7536) mg / kg 2 Silicon content of liquid fraction (ASTM D5185) mg / kg < 1

[0343] All or part of the liquid fraction obtained can then be valorized in a steam cracking step in order to form olefins which can be polymerized in order to form recycled plastics.

[0344] The feedstock consisting of a mixture of plastic pyrolysis oil and tire pyrolysis oils has a significant sulfur content (355 ppm wt). This sulfur, which is in the form of sulfur molecules, is hydrogenated in the reaction section and transformed into hydrogen sulfide (H2S). This H2S, in the form of The partial pressure of H2S (ppH2S) of 0.0027 MPa abs at the outlet of the hydrotreating reactor contributes to maintaining the sulfide phase of the NiMo catalysts on alumina and therefore to the catalyst activity. Consequently, the loss of catalytic activity in step c) of hydrotreating is low (< 1°C less) and it is not necessary to inject hydrogen sulfide or a sulfur compound such as DMDS to maintain catalytic activity. Example 3 (not in accordance with the invention)

[0345] According to Example 3, the processed feedstock is a plastics pyrolysis oil (i.e. comprising 100% by weight of said plastics pyrolysis oil) having the characteristics indicated in Table 12.

[0346] Table 12: Load characteristics

[0347] [Tables 12] Property Method NF EN ISO 12185 ASTM D159 Unit Plastics Pyrolysis Oil Density at 15°C g / cm³ 0.798 Bromine Value g / 100 g 50 MAV IFPEN 9407 mg / g 11 S ASTM D5453 mg / kg 67 N ASTM D4629 mg / kg 871 Cl ASTM D7536 mg / kg 95 Si ASTM D5185 mg / kg 20 Simulated Distillation ASTM D2887 Initial Boiling Point (0.50%) °C 60 10% °C 134 30% °C 199 50% °C 270 70% °C 335 90% °C 403 Final Boiling Point (99.50%) °C 574

[0348] The pyrolysis oil of plastics according to example 3 is treated under the same conditions as pyrolysis oil of tyres according to example 1.

[0349] The plastic pyrolysis oil feed contains very little sulfur (67 ppm wt). This sulfur, which is in the form of sulfur molecules, is hydrogenated in the reaction section and transformed into H2S. This H2S, in the form of a partial pressure of H2S (ppH2S) of 0.0004 MPa abs at the outlet of the hydrotreating reactor, partially contributes to maintaining the sulfide phase of the ca NiMo catalysts on alumina. However, the ppH2S obtained with this sulfur content in the feed (67 ppm wt) is insufficient to maintain the catalysts in the sulfide phase throughout the cycle. This results in a rapid deactivation of catalyst activity. Example 4 (not in accordance with the invention)

[0350] According to Example 4, the feed treated is identical to the plastics pyrolysis oil treated in Example 3. The feed according to Example 4 is treated under the same conditions as in Example 3, but H₂S is added to the reaction system to achieve a sufficient ppH₂S. This addition of H₂S can be done by injecting it into the dimethyl disulfide pyrolysis oil (DMDS) feed at the unit inlet. The DMDS decomposes readily upon contact with the catalyst into CH₄ and H₂S, thus generating a sufficient ppH₂S to maintain the catalysts in sulfide form. This method results in high DMDS consumption, which is detrimental to the economics of the process.

[0351] Given the sulfur content of the feedstock, DMDS is injected at a concentration of 800 ppm (equivalent to 544 ppm by weight of sulfur) to achieve the same partial pressure of hydrogen sulfide as that obtained in Example 2, i.e., 0.0027 MPa abs. For a processing capacity of 10 T / h of feedstock, this represents a DMDS consumption of 8.0 kg / h and therefore a significant operating and environmental cost. Example 5 (not in accordance with the invention)

[0352] According to Example 5, the feedstock treated is identical to the plastic pyrolysis oil treated in Example 3, except that it has a very high chlorine content (2000 ppm wt.) and a nitrogen content of 700 ppm wt. The plastic pyrolysis oil according to Example 5 is treated under the same conditions as the tire pyrolysis oil according to Example 3. An injection of 16.5 kg / h of aniline is required to capture all the Cl ions. Example 6 (according to the invention)

[0353] According to Example 6, the feedstock treated is a mixture comprising 15 wt% of tire pyrolysis oil of Example 1 (with a nitrogen content of 2720 ppm wt) and 85 wt% of plastic pyrolysis oil of Example 5 (with a sulfur content of 2000 ppm wt and a nitrogen content of 700 ppm wt). The feedstock according to Example 6 is treated under the same conditions as the feedstock (100 wt plastic oil) according to Example 5. It is not necessary to inject an amine since the tire pyrolysis oil provides the nitrogen necessary to capture all the Cl ions. Furthermore, it is not necessary to inject hydrogen sulfide or a sulfur compound such as DMDS to maintain catalytic activity.

Claims

Claims

1. A method of treating a feedstock comprising at least 5% by weight of a tire pyrolysis oil relative to the total weight of the feedstock, said tire pyrolysis oil having a sulfur content of between 2000 and 10000 ppm by weight relative to the total weight of the oil, said method comprising the following steps: a) optionally a selective hydrogenation step carried out in a reaction section implementing at least one fixed-bed reactor having n catalytic beds, n being an integer greater than or equal to 1, each comprising at least one selective hydrogenation catalyst, said selective hydrogenation reaction section being supplied at least by said feedstock and a gas stream comprising hydrogen, in the presence of at least one selective hydrogenation catalyst, at an average temperature between 100 and 280°C, a partial pressure of hydrogen between 1.0 and 10.0 MPa abs. and an hourly volumetric flow rate between 0.1 and 10.0 h1, to obtain a selectively hydrogenated effluent; b) a hydrogenation step carried out in a hydrogenation reaction section, using at least one fixed bed reactor having n catalytic beds, n being an integer greater than or equal to 1, each comprising at least one hydrogenation catalyst, said hydrogenation reaction section being fed at least by said feedstock or said selectively hydrogenated effluent from step a) and a gas stream comprising hydrogen, said hydrogenation reaction section being carried out at an average temperature between 140 and 400°C, a partial pressure of hydrogen between 1.0 and 10.0 MPa abs.and an hourly volumetric flow rate between 0.1 and 10.0 h *, to obtain a hydrogenated effluent, c) a hydrotreatment step carried out in a hydrotreatment reaction section, using at least one fixed-bed reactor having n catalytic beds, n being an integer greater than or equal to 1, each comprising at least one hydrotreatment catalyst, said hydrotreatment reaction section being fed at least with said hydrocarbon effluent from step d) when the separation step d) is carried out between steps b) and c), and / or at least with the hydrogenated effluent from step b) when the separation step d) is carried out after step c), and a gas stream comprising. hydrogen, said hydrotreatment reaction section being carried out at an average temperature between 250 and 430°C, a hydrogen partial pressure between 1.0 and 10.0 MPa abs. and an hourly volumetric flow rate between 0.1 and 10.0 h1, to obtain a hydrotreated effluent, d) a separation step, carried out between steps b) and c) and / or after step c), said step being fed with the hydrogenated effluent from step b) when separation step d) is carried out between steps b) and c), and / or with the hydrotreated effluent from step c) when separation step d) is carried out after step c), and an aqueous solution, said step being carried out in a separation section, to obtain at least one gaseous effluent, one aqueous effluent and one hydrocarbon effluent.

2. A method according to claim 1, wherein the feedstock comprises plastic pyrolysis oil and / or recovered solid fuels.

3. A method according to any preceding claim, wherein the feedstock consists of tire pyrolysis oil and plastic pyrolysis oil(s) and / or solid recovered fuels.

4. Method according to one of the preceding claims, in which the feedstock comprises a tire pyrolysis oil in a content of between 5 and 99% by weight and a plastic pyrolysis oil and / or solid recovered fuels in a content of between 1 and 95% by weight relative to the total weight of the feedstock.

5. Method according to one of the preceding claims, in which the separation step d) comprises the following steps: dl) a separation step, fed with the hydrogenated effluent from step b) when the separation step d) is carried out between steps b) and c), and / or with the hydrotreated effluent from step c) when the separation step d) is carried out after step c), said step being carried out at a temperature higher than the precipitation temperature of the ammonium halides and at a pressure substantially identical to the pressure of step b) to obtain at least a first gaseous effluent and a liquid effluent, a part of which is optionally recycled, as recycled effluent, upstream of step b), d2) a separation step, fed with the first gaseous effluent and optionally at least a part of the liquid effluent from step dl), and an aqueous solution, said step being carried out at a temperature lower than the precipitation temperature of the ammonium halides and at a pressure substantially identical to or lower than the pressure of step b), to obtain at least a second gaseous effluent, an aqueous effluent and a hydrocarbon effluent.

6. Method according to the preceding claim, in which step dl) is carried out at a temperature between 200 and 450°C and step d2) is carried out at a temperature greater than or equal to 20°C and less than 200°C.

7. Method according to one of the preceding claims, comprising at least one step of pretreatment of the feedstock comprising a tire pyrolysis oil, said pretreatment step being carried out upstream of step a) and / or upstream of step b) and comprises an adsorption step and / or a filtration step and / or a centrifugation step and / or a decantation step and / or an electrostatic separation step and / or a step of washing using an aqueous solution and / or a gas stripping step.

8. Process according to one of the preceding claims, comprising a step e) of fractionation of all or part of the hydrocarbon effluent from step d) when the separation step d) is carried out after step c), and / or of all or part of the hydrotreated effluent from step c) when the separation step d) is carried out between steps b) and c), to obtain at least one gas stream, a naphtha cut and at least one middle distillate cut.

9. Process according to one of the preceding claims, comprising at least one hydrocracking step f) carried out in a hydrocracking reaction section, using at least one fixed-bed reactor having n catalytic beds, n being an integer greater than or equal to 1, each comprising at least one hydrocracking catalyst, said hydrocracking reaction section being fed with at least a portion of said hydrocarbon effluent from step d) when the separation step d) is carried out after step c), and / or with at least a portion of the hydrotreated effluent from step c) when the separation step d) is carried out between steps b) and c), and / or with at least a portion of the middle distillate cut from the fractionation step e) and a gas stream comprising hydrogen, said hydrocracking reaction section being carried out at an average temperature between 250 and 450°C, a partial pressure of hydrogen between 1.5 and 20.0 MPa abs. and an hourly volumetric flow rate between 0.1 and 10.0 h 1 to obtain a first hydrocracked effluent.

10. Process according to one of the preceding claims, in which said hydrogenation catalyst of step b) comprises a support chosen from alumina, silica, silica-aluminas, magnesia, clays and their mixtures and a hydro-dehydrogenating function comprising either at least one element from group VIII and at least one element from group VIB, or at least one element from group VIII.

11. Process according to one of the preceding claims, in which said one hydrotreatment catalyst of step c) comprises a support chosen from alumina, silica, silica-aluminas, magnesia, clays and their mixtures, and a hydro-dehydrogenating function comprising at least one element from group VIII and / or at least one element from group VIB.

12. Process according to one of the preceding claims, in which at least a portion of the hydrocarbon effluent from step d) when the separation step d) is carried out after step c), and / or at least a portion of the hydrotreated effluent from step c) when the separation step d) is carried out between steps b) and c) and / or at least one of the cuts from the fractionation step e) is sent to a steam cracking step g) carried out in at least one pyrolysis furnace at a temperature of between 700 and 900°C and at a pressure of between 0.05 and 0.3 MPa relative.

13. Process according to one of the preceding claims comprising step a) of selective hydrogenation.

14. Process according to the preceding claim, in which said selective hydrogenation catalyst of step a) comprises a support chosen from alumina, silica, silica-aluminas, magnesia, clays and mixtures thereof, and a hydro-dehydrogenating function comprising at least one element from group VIII and / or at least one element from group VIB.

15.

16. Product obtained by the process according to one of claims 1 to 14. Product according to claim 15, which comprises, relative to the total weight of the product: - a total content of metallic elements less than or equal to 10.0 ppm by weight, - including an iron element content less than or equal to 200 ppb by weight, and / or - a silicon element content less than or equal to 5.0 ppm by weight, and / or - a sulfur content less than or equal to 100 ppm by weight, and / or - a nitrogen content less than or equal to 100 ppm by weight, and / or - a chlorine element content of less than or equal to 10 ppm by weight, and / or - a mercury content less than or equal to 5 ppb by weight.

17. Product according to claims 15 and 16 comprising a biological carbon content according to ASTM D6866 of between 1 and 70% by weight.

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