Process for simultaneously treating plastics pyrolysis oils and a feedstock derived from renewable sources

Abstract

This invention relates to a method for processing a feedstock containing plastic pyrolysis oil and a feedstock derived from a renewable source, comprising: a) selectively hydrogenating the feedstock containing plastic pyrolysis oil, as appropriate; b) hydrodemetallizing the feedstock containing plastic pyrolysis oil or the effluent from step a); c) hydrogenating the effluent obtained from step b), wherein the feedstock derived from the renewable source is introduced into steps a) and / or b) and / or c), the weight ratio between the flow rate of the feedstock containing the plastic pyrolysis oil and the flow rate of the feedstock derived from the renewable source is between 0.05 and 20; and d) separating the feedstock in the presence of an aqueous stream.

Description

Technical Field

[0001] This invention relates to a method for simultaneously processing plastic pyrolysis oil and feedstocks from renewable sources to obtain a hydrocarbon-based effluent, which may be incorporated, for example, directly into a naphtha or diesel fuel cell or used as feedstock for purification in a steam cracking unit. More specifically, this invention relates to a method for simultaneously processing feedstocks from the pyrolysis of plastic waste and feedstocks from renewable sources to at least partially remove impurities that may be present in relatively high quantities in these feedstocks. Prior Technology

[0002] Plastics obtained from collection and sorting channels can undergo a pyrolysis step to obtain pyrolysis oil. This pyrolysis oil is typically burned to generate electricity and / or used as fuel for industrial furnaces or municipal heating.

[0003] Another approach to purifying plastic pyrolysis oil is to use it as feedstock in a steam cracking unit to (re)generate olefins, which are monomers of certain polymers. However, plastic waste is generally a mixture of several polymers, such as polyethylene, polypropylene, polyethylene terephthalate, polyvinyl chloride, and polystyrene. Furthermore, depending on the application, plastics may contain other compounds besides polymers, such as plasticizers, pigments, dyes, or polymerization catalyst residues. Plastic waste may also contain trace amounts from renewable sources, such as municipal solid waste. The treatment of waste, especially storage, mechanical processing, sorting, and pyrolysis, as well as the storage and transportation of pyrolysis oil, can cause corrosion. Therefore, oil obtained from the pyrolysis of plastic waste contains a large number of impurities, specifically dienes, metals, metalloids (especially iron and silicon), or halogenated compounds (especially chlorine-based compounds); heterogeneous elements, such as sulfur, oxygen, and nitrogen; and often higher levels of insoluble matter in the contents of the steam cracking unit or downstream units (especially polymerization and selective hydrogenation processes). These impurities can cause operational problems, particularly corrosion, coking, or catalyst deactivation, or incompatibility issues in the application of the target polymer. The presence of dienes can also cause instability problems in pyrolysis oils, characterized by the formation of gels. The gels and insolubles that may be present in the pyrolysis oil can lead to clogging problems in the process.

[0004] Furthermore, during the steam cracking step, the yield of light olefins (especially ethylene and propylene) sought for petrochemical use largely depends on the quality of the feedstock sent to the steam cracker. The Bureau of Mines Correlation Index (BMCI) is commonly used to characterize hydrocarbon fractions. Calculated from measurements of density and average boiling point, this index is applied to hydrocarbon-based products derived from crude oil: it equals 0 for straight-chain alkanes and 100 for benzene. Higher values ​​are observed if the analyzed products have aromatic condensation structures, with cycloalkanes containing intermediate BMCI values ​​between the alkanes and aromatics. Generally, the yield of light olefins increases with increasing alkane content and therefore increases with decreasing BMCI. Conversely, the yield of undesirable heavy compounds and / or coke increases with increasing BMCI.

[0005] Over the past few decades, there has been considerable interest in integrating refining methods for novel plant-derived products derived from the conversion of renewable sources of lignocellulose or from the production of vegetable oils or animal fats, driven by rising costs of fossil materials and the need to reduce the carbon footprint of transportation. Consequently, many biofuels (primarily ethanol, methyl esters of vegetable oils, and hydrogenated vegetable oils) have achieved real-world status as petroleum-based supplements in fuel pools.

[0006] Hydrogenation of triglycerides and fatty acids derived from biological and / or animal sources makes it possible to obtain long-chain alkanes, which may be hydroisomerized as appropriate for incorporation into fuel pools of injector fuels or diesel fuels.

[0007] However, the rapid electrification of land-based transport vehicles could limit reliance on biologically derived feedstocks in the coming years. Therefore, there is an advantage to finding new upgrade methods.

[0008] WO 2018 / 055555 discloses a general method for recycling plastic waste, which is extremely general and relatively complex, encompassing steps from pyrolysis of plastic waste to steam cracking. The method in application WO 2018 / 055555 specifically includes: a step of hydrogenating the liquid phase obtained from direct autopyrolysis, preferably under rather stringent conditions, particularly in terms of temperature, for example, between 260 and 300°C; a step of separating the hydrogenated effluent; and a subsequent step of hydrogenating and dealkylating the separated heavy effluent, preferably at a high temperature, for example, between 260 and 400°C.

[0009] Unpublished patent application FR 20 / 01758 describes a method for treating plastic pyrolysis oil, comprising: a) Selectively hydrogenate the feedstock in the presence of hydrogen and a selective hydrogenation catalyst to obtain a hydrogenated effluent; b) The hydrogenated effluent is hydrogenated in the presence of hydrogen and a hydrogenation catalyst to obtain a hydrogenated effluent; c) In the presence of an aqueous stream, the hydrotreated effluent is separated at a temperature between 50 and 370°C to obtain a gaseous effluent, an aqueous liquid effluent, and a hydrocarbon-based liquid effluent; d) A fractionation step, as appropriate, wherein all or part of the fractionation is obtained from the hydrocarbon-based effluent of step c), to obtain a gas stream and at least two hydrocarbon-based streams, which may be naphtha fractions and heavier fractions; e) A recycling step comprising recovering a portion of the hydrocarbon-based effluent obtained from separation step c) or a portion of the hydrocarbon-based stream obtained from fractionation step d) and / or at least one of them to a stage of selective hydrogenation step a) and / or hydrotreating step b).

[0010] Document FR2910017 discloses a method for processing petroleum-based and bio-based feedstocks, wherein the petroleum-based feedstock is injected into a catalytic section located upstream of the injection point of the bio-based feedstock. The solution described in document FR2910017 is incompatible with processing plastic pyrolysis oil in mixtures with bio-based feedstocks.

[0011] Therefore, the simultaneous processing of plastic pyrolysis oil and feedstocks from renewable sources allows for the optimization of both feedstocks by effectively removing existing impurities and converting them into refining products. For the purpose of generating olefins, these products can be used, in particular, as feedstocks for steam-cracking units. After polymerization, these olefins enable the production of polymers not only from the plastic source of the pyrolysis oil but also from bio-based sources. These products can also be upgraded into a foundation for fuel pools. Summary of the Invention

[0012] This invention relates to a method for processing feedstocks comprising plastic pyrolysis oil and feedstocks derived from renewable sources, comprising: a) A selective hydrogenation step, selected as appropriate, is carried out in the presence of at least one selective hydrogenation catalyst at a temperature between 80 and 280°C, a hydrogen partial pressure between 1.0 and 20.0 MPa abs., and a space velocity between 0.3 and 10.0 h⁻¹, in a reaction section fed with at least the feedstock containing the plastic pyrolysis oil and a gas stream containing hydrogen, to obtain a hydrogenated effluent. b) A hydrodemetallization step, performed in a hydrodemetallization reaction section comprising at least one hydrodemetallization catalyst, the hydrodemetallization reaction section being fed at least a feedstock comprising plastic pyrolysis oil and / or the hydrogenated effluent from step a) and a hydrogen-containing gas stream, the hydrodemetallization reaction section being carried out at an average temperature between 140 and 400°C, a hydrogen partial pressure between 1.0 and 20.0 MPa abs., and a space velocity between 0.1 and 10.0 h⁻¹, to obtain a demetallized effluent. c) A hydrotreating step, performed in a hydrotreating reaction section comprising at least one hydrotreating catalyst, the hydrotreating reaction section being fed at least the demetallized effluent obtained from step b) and a hydrogen-containing gas stream, the hydrotreating reaction section being operated at a temperature between 250 and 450°C, a hydrogen partial pressure between 1.0 and 10.0 MPa abs., and a space velocity between 0.1 and 10.0 h⁻¹ to obtain the hydrotreating effluent; Furthermore, the raw material derived from a renewable source is introduced, as appropriate, as a mixture with the raw material containing plastic pyrolysis oil in steps a) and / or b) and / or c). The weight ratio between the flow rate of the feedstock containing the plastic pyrolysis oil and the flow rate of the feedstock introduced from renewable sources is between 0.05 and 20. c') A hydrocracking step, selected as appropriate, is performed in a hydrocracking reaction section containing at least one hydrocracking catalyst. This hydrocracking reaction section is fed at least the hydrotreated effluent from step c') and / or the fraction containing compounds with boiling points greater than 175°C from step e') and a hydrogen-containing gas stream. The hydrocracking reaction section is operated at an average temperature between 250 and 450°C, a hydrogen partial pressure between 1.5 and 20.0 MPa abs., and a space velocity between 0.1 and 10.0 h⁻¹ to obtain the hydrocracking effluent to be conveyed to the separation step d'). d) A separation step, wherein the feed consists of the hydrotreated effluent from step c) and / or the hydrocracked effluent from step c') and an aqueous solution, the step being performed at a temperature between 50 and 450°C to obtain at least one gaseous effluent, an aqueous effluent, and a hydrocarbon-based effluent. e) Select, as appropriate, a fractionation step of all or part of the hydrocarbon-based effluent obtained from step d) to obtain at least one gaseous effluent and at least one fraction containing a compound with a boiling point less than or equal to 175°C and a hydrocarbon fraction containing a compound with a boiling point greater than 175°C.

[0013] One advantage of the method of the present invention is that it simultaneously purifies feedstocks comprising oil obtained from the pyrolysis of plastic waste and feedstocks derived from renewable sources to at least partially remove impurities and hydrogenate such feedstocks, thereby enabling the purification of the obtained products, particularly by directly incorporating them into a fuel pool and / or by making them compatible with the processing in a steam cracking unit, to obtain light olefins, which can be used as monomers in the manufacture of polymers.

[0014] The most significant feature of the method of this invention is its great flexibility, making it possible to introduce raw materials derived from renewable resources into each step of the method, depending on their impurities. In practice, when raw materials derived from renewable resources contain numerous impurities, they can be partially or completely introduced into steps a) and / or b). When such treatment is not necessary, raw materials derived from renewable resources can also be partially or completely introduced into step c).

[0015] Another advantage of this invention is the limitation of the temperature rise between the inlet and outlet of plug flow reactors (e.g., fixed beds), particularly that induced by heat release from the hydrotreating of feedstocks derived from renewable sources, which is partially absorbed by the simultaneously processed plastic pyrolysis oil. This results in an optimized method whose limits are significantly dependent on the recycling of the effluent and / or gas and / or liquid cooling streams.

[0016] Therefore, the method of the present invention makes it possible to obtain hydrocarbon-based effluents from plastic pyrolysis oil and feedstocks derived from renewable sources, and to remove at least partially the initial impurities therefrom, thus limiting the operability problems such as corrosion, coking, or catalyst deactivation that these impurities may cause, particularly in steam cracking units and / or downstream units (especially polymerization and selective hydrogenation units). The removal of at least some of the impurities from oils obtained from plastic waste pyrolysis and feedstocks derived from renewable sources also makes it possible to increase the applicability of the target polymer and reduce application incompatibilities.

[0017] According to one variation, the method of the present invention includes a fractionation step e).

[0018] According to one variation, the method of the present invention includes a hydrocracking step c').

[0019] According to one variation, the method of the present invention includes the selective hydrogenation step a).

[0020] According to one variation, raw materials derived from renewable sources include oils and / or fats of plant and / or animal origin.

[0021] According to one variation, at least a portion of the raw material derived from renewable resources is introduced in step c).

[0022] According to one variation, the temperature of the reaction zone in step c) is higher than the temperature of the hydrogenation demetallization reaction zone in step b).

[0023] According to a variation, at least a portion of the hydrocarbon-based effluent obtained from separation step d) or at least a portion of the naphtha fraction containing compounds with a boiling point less than or equal to 175°C obtained from fractionation step e) is fed as a recycle stream to selective hydrogenation step a) and / or hydrodemetallization step b) and / or hydrotreatment step c).

[0024] According to one variation, at least a portion of the fraction containing compounds with boiling points greater than 175°C obtained from fractionation step e) is fed as a recycle stream to hydrodemetallization step b) and / or hydrotreatment step c) and / or hydrocracking step c').

[0025] According to one variation, the weight ratio between the recycled stream and the feedstock containing plastic pyrolysis oil and feedstock from renewable sources is less than or equal to 10.

[0026] According to one variation, the method of the present invention includes a step a0) of pretreating the raw materials, which is carried out upstream of the selective hydrogenation step a) and includes a filtration step and / or an electrostatic separation step and / or a washing step by means of an aqueous solution and / or an adsorption step.

[0027] According to a variation, at least one of the hydrocarbon-based effluent obtained from separation step d) or the two hydrocarbon-based liquid streams obtained from step e) is wholly or partially transported to a steam cracking step f) carried out in at least one pyrolysis furnace at a temperature between 700 and 900°C and a pressure between 0.05 and 0.3 MPa.

[0028] According to one variation, the selective hydrogenation catalyst comprises a support and a hydrodehydrogenation function, wherein the support is selected from alumina, silicon dioxide, silicon dioxide-alumina, magnesium oxide, clay, and mixtures thereof, and the hydrodehydrogenation function comprises at least one Group VIII element and at least one Group VIB element, or at least one Group VIII element.

[0029] According to one variation, the hydrodemetallization catalyst and the hydrotreatment catalyst comprise a support and hydrodehydrogenation functionality, wherein the support is selected from the group consisting of alumina, silicon dioxide, silicon dioxide-alumina, magnesium oxide, clay, and mixtures thereof, and the hydrodehydrogenation functionality comprises at least one group VIII element and / or at least one group VIB element.

[0030] According to a variation, the method of the present invention also includes a second hydrocracking step c'') performed in a hydrocracking reaction section containing at least one hydrocracking catalyst, the hydrocracking reaction section being fed a fraction containing compounds with a boiling point greater than 175°C obtained from step e) and a gas stream containing hydrogen, the hydrocracking reaction section being operated at a temperature between 250 and 450°C, a hydrogen partial pressure between 1.5 and 20.0 MPa abs., and a space velocity between 0.1 and 10.0 h⁻¹, to obtain the hydrocracking effluent to be conveyed to the separation step d).

[0031] According to one variation, the hydrocracking catalyst comprises a support and hydrodehydrogenation functionality, wherein the support is selected from a combination of alumina halides, boron and aluminum oxides, amorphous silica-alumina, and zeolites, and the hydrodehydrogenation functionality comprises at least one group VIB metal selected from chromium, molybdenum, and tungsten alone or in mixtures, and / or at least one group VIII metal selected from iron, cobalt, nickel, ruthenium, rhodium, palladium, and platinum.

[0032] According to one variation, the raw material has the following characteristics: - The content of aromatic compounds is between 0% and 90% by weight. - The content of halogenated compounds is between 2 and 5000 ppm by weight. - The content of metallic elements is between 10 and 10,000 ppm by weight. - Including iron content between 0 and 100 ppm by weight, - The silicon content is between 0 and 1000 ppm by weight.

[0033] This invention also relates to products that can be obtained by the processing method according to the invention.

[0034] According to one variation, the product comprises, relative to its total weight: - The total content of metallic elements is less than or equal to 5.0 ppm by weight. - The iron content, by weight, is less than or equal to 100 ppb. - The silicon content is less than or equal to 1.0 ppm by weight. - Sulfur content is less than or equal to 500 ppm by weight. - Nitrogen content is less than or equal to 100 ppm by weight. - The chlorine content is less than or equal to 10 ppm by weight. []

[0035] According to the present invention, unless otherwise indicated, pressure is absolute pressure, also written as abs. and given in absolute megapascals (or MPa abs.).

[0036] According to the present invention, the expression "contained between..." and "between..." is equivalent to "between..." and means that the limit value of the interval is included within the range of values ​​described. If this is not the case and if the limit value is not included within the range described, such clarification will be provided by the present invention.

[0037] For the purposes of this invention, various ranges of parameters for a given step, such as pressure ranges and temperature ranges, can be used individually or in combination. For example, for the purposes of this invention, a preferred pressure range can be combined with a preferred temperature range.

[0038] Specific and / or preferred embodiments of the invention may be described herein. Where technically feasible, these embodiments may be implemented separately or in combination without limitation.

[0039] Subsequently, chemical element groups were assigned according to the CAS classification (CRC Handbook of Chemistry and Physics, published by CRC Press, edited by DR Lide, 81st edition, 2000-2001). For example, Group VIII according to the CAS classification corresponds to metals in rows 8, 9, and 10 according to the new IUPAC classification.

[0040] Metal content is measured by X-ray fluorescence. Simple Explanation of the Diagram

[0041] Figure 1 illustrates a flow chart of a specific embodiment of the method of the present invention. Figure 2 illustrates the flow of another specific embodiment of the method of the present invention, which is based on the flow of Figure 1. Implementation

[0042] [raw material] [] According to the present invention, the raw materials processed in the method of the present invention are raw materials comprising plastic pyrolysis oil and raw materials derived from renewable sources.

[0043] "Plastic pyrolysis oil" is an oil derived from the pyrolysis of plastics, preferably particularly from plastic waste collected and sorted in the industry. Specifically, it comprises hydrocarbon-based compounds, particularly a mixture of alkanes, mono- and / or dienes, cycloalkanes, and aromatics. At least 80% by weight of these hydrocarbon-based compounds preferably have a boiling point below 700°C, and more preferably below 550°C. Specifically, depending on the source of the pyrolysis oil, the oil contains up to 70% by weight of alkanes, up to 90% by weight of olefins, and up to 90% by weight of aromatics; it should be understood that the sum of alkanes, olefins, and aromatics is 100% by weight of hydrocarbon-based compounds.

[0044] The density of pyrolysis oil measured at 15°C according to ASTM D4052 is generally between 0.75 and 0.99 g / cm³, preferably between 0.75 and 0.95 g / cm³.

[0045] Plastic pyrolysis oil may also contain, and often does contain, impurities such as metals, especially iron, silicon, or halogenated compounds, especially chlorinated compounds. High levels of these impurities can be present in plastic pyrolysis oil, for example, up to 350 ppm, 700 ppm, or even 1000 ppm by weight of halogenated elements (especially chlorine), and up to 100 ppm or even 200 ppm by weight of metallic or semi-metallic elements. Alkali metals, alkaline earth metals, transition metals, post-transition metals, and metalloids can be likened to metallic contaminants and are referred to as metals or metallic elements or semi-metallic elements. Specifically, the metals or metallic elements or semi-metallic elements that may be present in oil obtained from the pyrolysis of plastic waste include silicon, iron, or both. Plastic pyrolysis oil may also contain other impurities, such as heterologous elements provided, especially by sulfur compounds, oxygen compounds and / or nitrogen compounds, generally less than 10,000 ppm by weight and preferably less than 4,000 ppm by weight.

[0046] Plastic pyrolysis oil can be prepared by autothermal catalytic pyrolysis or by additional hydropyrolysis (pyrolysis in the presence of a catalyst and hydrogen).

[0047] The raw materials processed in the method of this invention also include those derived from renewable sources.

[0048] According to the first variation, the raw materials derived from renewable sources are advantageously selected from oils and / or fats of plant and / or animal origin. The plant and / or animal-derived oils or fats used in this invention contain triglycerides and / or free fatty acids and / or esters. Vegetable oils may advantageously be crude or wholly or partially refined and are derived from plants such as rapeseed, sunflower, soybean, palm, palm kernel, olive, coconut, and Jatropha curcas, without limitation. Algae oil or fish oil is also relevant. Animal fats are advantageously selected from residues from the food industry or from lard or fats derived from the catering industry.

[0049] These raw materials essentially contain chemical structures known to those skilled in the art as triglycerides and / or triglycerides of free fatty acids. Therefore, a triglyceride is composed of three fatty acid chains. These fatty acid chains, in triester or free fatty acid form, have multiple degrees of unsaturation per chain, also known as multiple carbon-carbon double bonds per chain, generally between 0 and 3, but can be higher, especially in oils derived from algae, typically with 5 to 6 degrees of unsaturation per chain.

[0050] Therefore, the molecules present in the raw materials containing oils or fats or plant and / or animal sources used in this invention have multiple degrees of unsaturation per molecule, advantageously between 0 and 18. In these raw materials, the ratio between the sum of the number of unsaturated molecules and the number of molecules is advantageously between 0 and 6.

[0051] According to the second variation, the feedstock derived from renewable sources is advantageously selected from feedstocks derived from methods for thermal and / or catalytic conversion of lignocellulose biomass, such as oils produced from lignocellulose biomass by 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 byproducts. The term "lignocellulose biomass" indicates a renewable source derived from plants and their byproducts. Renewable sources of lignocellulose consist of carbohydrate polymers (cellulose, hemicellulose) and aromatic polymers (lignin).

[0052] These raw materials, derived from renewable sources, may be crude, refined, or semi-refined and may contain impurities, particularly phospholipids, alkali metals, and alkaline earth metals, especially iron, phosphorus, sodium, calcium, and magnesium.

[0053] Preferably, the raw materials derived from renewable sources include oils and / or fats of plant and / or animal origin.

[0054] The raw materials of the method of the present invention comprise at least one plastic pyrolysis oil and at least one raw material derived from a renewable source. The raw materials may consist solely of plastic pyrolysis oil and a raw material derived from a renewable source. Preferably, the raw materials comprise at least 50% by weight, more preferably between 75% by weight and 100% by weight, of plastic pyrolysis oil and a raw material derived from a renewable source; in other words, preferably between 50% by weight and 100% by weight, more preferably between 70% by weight and 100% by weight, of plastic pyrolysis oil and a raw material derived from a renewable source.

[0055] The weight ratio between the flow rate of the feedstock containing plastic pyrolysis oil and the flow rate of the feedstock derived from a renewable source introduced into the method of the present invention is generally between 0.02 and 50, typically between 0.05 and 20, and preferably between 0.1 and 10. The term "weight ratio" is intended to refer to the total weight ratio in the method of the present invention, and is independent of the step of introducing the feedstock derived from a renewable source.

[0056] The raw materials for the method of the present invention may also include conventional petroleum-based feedstocks, which are subsequently co-processed with plastic pyrolysis oil and feedstocks derived from renewable sources. Advantageously, conventional petroleum-based feedstocks may be fractions or types of naphtha, gaseous oil, or mixtures of fractions of gaseous oil under vacuum. In this case, the petroleum-based feedstock may be injected in steps a) and / or b) and / or c) and / or c'), and preferably in step c).

[0057] [] [Preprocessing] [(] [Select as needed] [)] [] The feedstock containing plastic pyrolysis oil and / or feedstock derived from renewable resources may advantageously be pretreated in a pretreatment step a0) as appropriate prior to the selective hydrogenation step a) to obtain at least one pretreated feedstock for feeding into step a) or step b).

[0058] The raw materials pretreated in step a0) as appropriate may include, in particular: - A mixture of plastic pyrolysis oil and raw materials derived from renewable sources. - It contains raw materials derived from plastic pyrolysis oil, but none from renewable sources. It is derived from renewable sources and contains no plastic pyrolysis oil. - Two different streams, one of which contains plastic pyrolysis oil and the other of which contains feedstock from a renewable source, are processed in parallel in pretreatment step a0) under different processing conditions and operations.

[0059] When the raw material pretreated in step a0) is a raw material containing plastic pyrolysis oil and there is no raw material from a renewable source, the raw material from a renewable source may be introduced into step a) and / or step b) and / or step c), and the pretreated raw material containing plastic pyrolysis oil may be introduced into step a) or step b) as appropriate.

[0060] When the raw material pretreated in step a0) is from a renewable source and does not contain plastic pyrolysis oil, the raw material containing plastic pyrolysis oil may be introduced into step a) and / or step b) as appropriate, and the pretreated raw material from a renewable source may be introduced into step a) and / or step b) and / or step c) as appropriate.

[0061] This pretreatment step a0), selected as appropriate, makes it possible to reduce the amount of contaminants that may be present in feedstocks containing plastic pyrolysis oil and / or feedstocks derived from renewable sources, particularly the amounts of iron and / or silicon and / or chlorine and / or phosphorus and / or sodium and / or calcium. Therefore, the pretreatment step a0), selected as appropriate, for feedstocks containing plastic pyrolysis oil and / or feedstocks derived from renewable sources, is advantageously performed, particularly when the feedstock contains more than 10 ppm by weight, particularly more than 20 ppm by weight, and more specifically more than 50 ppm by weight of a metallic element, and especially when the feedstock contains more than 5 ppm by weight of silicon, more specifically more than 10 ppm by weight or even more than 20 ppm by weight of silicon. Similarly, the pretreatment step a0), selected as appropriate, is advantageously performed, particularly when the feedstock contains more than 10 ppm by weight, particularly more than 20 ppm by weight, and more specifically more than 50 ppm by weight of chlorine. Similarly, the pretreatment step a0), selected as appropriate, is advantageously carried out, especially when the raw material contains phosphorus at a concentration greater than 100 ppm by weight, particularly greater than 200 ppm by weight, and more specifically greater than 500 ppm by weight. Likewise, the pretreatment step a0), selected as appropriate, is advantageously carried out, especially when the raw material contains acidic species that result in a TAN (total acid value) value greater than 1 mg KOH / g, or even greater than 3 mg KOH / g, or even greater than 6 mg KOH / g.

[0062] The pretreatment step (a0), chosen as appropriate, can be performed by any method known to those skilled in the art to reduce the amount of contaminants. It may include, in particular, a filtration step and / or an electrostatic separation step and / or a washing step by means of an aqueous solution and / or an adsorption step.

[0063] The pretreatment step a0, which may be selected as appropriate, is advantageously performed at a temperature between 0 and 150°C, preferably between 5 and 100°C, and at a pressure between 0.15 and 10.0 MPa abs, preferably between 0.2 and 1.0 MPa abs.

[0064] According to one variation, the pretreatment step a0), selected as appropriate, is performed in an adsorption section in the presence of at least one adsorbent of a preferred alumina type with a specific surface area greater than or equal to 100 m² / g, preferably greater than or equal to 200 m² / g. The specific surface area of ​​the at least one adsorbent is suitably less than or equal to 600 m² / g, specifically less than or equal to 400 m² / g. The specific surface area of ​​the adsorbent is the surface area measured by the BET method, i.e., the specific surface area determined by nitrogen adsorption according to the standard ASTM D 3663-78, derived from the Brunauer-Emmett-Teller method described in the periodic journal *The Journal of the American Chemical Society*, 60, 309 (1938).

[0065] Advantageously, the adsorbent contains less than 1% by weight of a metal element, and preferably contains no metal element. The term "metal element in the adsorbent" should be understood to refer to elements from Groups 6 to 10 of the periodic table (new IUPAC classification). The residence time of the feedstock in the adsorption zone is generally between 1 and 180 minutes.

[0066] The adsorption section of step a0), selected as appropriate, includes at least one adsorption column containing the adsorbent, preferably at least two adsorption columns, and more preferably two to four adsorption columns. When the adsorption section includes two adsorbent columns, one operating mode may be referred to as "swinging" according to technical terms, where one column is online (i.e., in use) and the other is in reserve. When the adsorbent in the online column is depleted, this column is isolated, leaving the reserve column online (i.e., in use). The depleted adsorbent can then be regenerated in situ and / or replaced with fresh adsorbent, allowing the column containing the adsorbent to be online again after the other column has been isolated.

[0067] Another operating mode involves at least two columns operating in series. When the adsorbent in the first column is depleted, this first column is isolated, and the depleted adsorbent is regenerated in situ or replaced with fresh adsorbent. The last column is then brought back online, and so on. This operating mode is called a switchable mode or a switchable reactor system (PRS), or, according to specific terminology, "lead and lag." The combination of at least two adsorption columns makes it possible to overcome the potential for rapid poisoning and / or clogging of the adsorbent due to the combined effects of metallic contaminants, dienes, colloids derived from dienes, phosphorus, sodium, calcium, and insoluble substances present in the feedstock being treated. This is because the presence of at least two adsorption columns facilitates the advantageous replacement and / or regeneration of the adsorbent without stopping the pretreatment unit or even the process, thus reducing the risk of clogging and thus avoiding unit shutdown due to clogging, thereby controlling costs and limiting adsorbent consumption.

[0068] According to another variation, the pretreatment step a0), selected as appropriate, is carried out in the washing section by contacting the feedstock with at least one washing liquid, which can be an organic solvent, an aqueous solution, or an aqueous solution containing organic compounds. Preferably, the washing liquid is an aqueous solution, which can be, for example, water, preferably demineralized water and carbonated water, or an acidic or alkaline solution. This washing section may contain devices for contacting the feedstock with the washing liquid and for separating the stages, so as to obtain, on the one hand, a pretreated feedstock, and on the other hand, a washing liquid containing impurities. Among these devices, there may be, for example, a stirred reactor, a decanter, a mixer-decanter, and / or a co-current or counter-current washing column. Advantageously, the washing column is a packed column, a disc, a stirred column, or a pulsed column; the ratio between the amount of washing liquid and the amount of feedstock is between 0.01 and 100, preferably between 0.1 and 10, and more preferably between 0.15 and 2.

[0069] The pretreatment step a0), which may be selected as appropriate, may also feed at least a portion of the recycle stream, which is advantageously obtained from step d) of the method or step e), which may be selected as appropriate, in the form of a mixture of feedstock containing plastic pyrolysis oil and / or feedstock derived from renewable resources, or separately containing feedstock containing plastic pyrolysis oil and / or feedstock derived from renewable resources.

[0070] Therefore, the pretreatment step a0) selected as appropriate makes it possible to obtain pretreated raw materials, which are then fed into selective hydrogenation step a) or hydrodemetallization step b).

[0071] [Selective hydrogenation step] [a) (] [Select as needed] [)] [] According to the present invention, the method may include step a), selective hydrogenation of a feedstock comprising plastic pyrolysis oil and, where appropriate, a feedstock derived from renewable resources (when the latter is injected into step a), performed in the presence of hydrogen at a hydrogen pressure and temperature that makes it possible to maintain the feedstock in a liquid phase, and with a certain amount of soluble hydrogen that is just necessary for the selective hydrogenation of the dienes present in the feedstock. Thus, selective hydrogenation of at least a portion of the liquid-phase dienes makes it possible to avoid or at least limit the formation of a "gel," i.e., the polymerization of the dienes, thereby forming oligomers and polymers that can block the reaction sections of the hydrodemetallization step b) and / or the hydrotreatment step c). Styrene compounds, where appropriate, present in the feedstock, particularly styrene, can also behave similarly to dienes in terms of gel formation because the vinyl double bonds are bonded to the aromatic nuclei. This selective hydrogenation step a) makes it possible to obtain a selectively hydrogenated effluent, i.e., an effluent containing a reduced content of olefins (specifically dienes) and, where appropriate, styrene.

[0072] According to the present invention, the selective hydrogenation step a) is performed in a reaction section where at least the feedstock containing plastic pyrolysis oil, which has been pretreated as appropriate, and a gas stream containing hydrogen (H2) are fed.

[0073] Depending on the circumstances, the reaction zone of step a) may also be fed with at least a portion of pre-treated feedstock derived from renewable resources.

[0074] Depending on the circumstances, the reaction zone of step a) may also be fed with at least a portion of the recycled stream from step d) of the method or, as appropriate, step e).

[0075] Feed from renewable resources and / or recycled streams can be fed in the form of a mixture with the feed containing plastic pyrolysis oil, or advantageously separately from the feed at the inlet of the reaction section in step a).

[0076] This reaction section involves selective hydrogenation, preferably in a fixed bed, in the presence of at least one selective hydrogenation catalyst, advantageously at an average temperature (or WABT as defined below) between 80 and 280 °C, more preferably between 120 and 260 °C, more preferably between 130 and 250 °C, at a hydrogen partial pressure between 1.0 and 20.0 MPa abs., more preferably between 5.0 and 15.0 MPa abs., and at a space-time velocity (HSV) between 0.3 and 10.0 h⁻¹, more preferably between 0.5 and 5.0 h⁻¹.

[0077] According to the present invention, the "temperature" of a reaction section comprising at least one fixed-bed reactor is the average temperature of the reaction section comprising at least one fixed-bed reactor and corresponds to the weight average bed temperature (WABT) in technical terms well known to those skilled in the art. The average temperature is advantageously determined based on the catalytic system, apparatus, and configuration used. The average temperature (or WABT) is calculated as follows: WABT = (T inlet + T outlet) / 2 Where T inlet: temperature of the effluent at the inlet of the reaction section, and T outlet: temperature of the effluent at the outlet of the reaction section.

[0078] Space velocity (HSV) is defined here as the ratio of the hourly volumetric flow rate of the feedstock entering the reaction zone to the volume of the catalyst. The expression "feedstock entering the reaction zone of step a)" is intended to mean, where applicable, all "fresh" feedstock that has been pretreated, i.e., including at least cracked oil and, where applicable, some or all of the feedstock derived from renewable resources, supplemented, where applicable, by the recycled stream obtained from steps d) and / or e).

[0079] The amount of hydrogen (H2) gas flow fed into the reaction zone of step a) is advantageously such that the hydrogen coverage is between 1 and 200 Nm3 hydrogen / m3 of the feedstock entering the reaction zone (Nm3 / m3), preferably between 1 and 50 Nm3 hydrogen / m3 of the feedstock (Nm3 / m3), and more preferably between 5 and 20 Nm3 hydrogen / m3 of the feedstock (Nm3 / m3).

[0080] Hydrogen coverage is defined as the ratio of the volumetric flow rate of hydrogen obtained under standard temperature and pressure conditions to the volumetric flow rate of feedstock that has been pretreated as appropriate and enters the reaction zone at 15°C without considering any recirculation (the unit is H2 / m3 feedstock in standard m3, written as Nm3).

[0081] The hydrogen-containing gas stream fed into the reaction zone of step a) may be composed of hydrogen supplied and / or advantageously obtained from recycled hydrogen from step d) or, as appropriate, step e).

[0082] The selective hydrogenation step a) is preferably carried out in a fixed bed. It can also be carried out in a fluidized bed or a moving bed.

[0083] Advantageously, the reaction section of step a) comprises 1 to 5 reactors. According to a particular embodiment of the invention, the reaction section comprises 2 to 5 reactors operating in a switchable mode, referred to by the term PRS or "swinging" for switchable reactor systems. A combination of reactors in at least two PRS modes makes it possible to isolate a reactor, discharge spent catalyst, reload the reactor with fresh catalyst, and return the reactor to operation without stopping the process. PRS technology is particularly described in patent FR2681871.

[0084] According to a particularly preferred variation, the selective hydrogenation reaction section of step a) is comprised of two fixed-bed reactors operating in a displacement mode.

[0085] Advantageously, reactor inserts of the filter plate type, for example, can be used to prevent reactor clogging. Examples of filter plates are described in patent FR3051375.

[0086] Advantageously, the selective hydrogenation catalyst includes a support (preferably a mineral support) and hydrogenation / dehydrogenation functionality.

[0087] According to one variation, the hydrodehydrogenation functionality particularly includes at least one Group VIII element preferably selected from nickel and cobalt, and at least one Group VIB element preferably selected from molybdenum and tungsten. According to this variation, the total content of oxides of Group VIB and Group VIII metal elements, expressed relative to the total weight of the catalyst, is preferably between 1 wt% and 40 wt%, and more preferably between 5 wt% and 30 wt%. 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.

[0088] The weight ratio of metal oxides of Group VIB metals to metal oxides of Group VIII metals is preferably between 1 and 20, and more preferably between 2 and 10.

[0089] According to this variation, the reaction section of step a) includes, for example, a hydrogenation catalyst, which comprises 0.5% to 12% by weight of nickel, preferably 1% to 10% by weight of nickel (in terms of the weight of nickel oxide NiO relative to the catalyst) on a support (preferably a mineral support, preferably an alumina support), and 1% to 30% by weight of molybdenum, preferably 3% to 20% by weight of molybdenum (in terms of the weight of molybdenum oxide MoO3 relative to the catalyst).

[0090] According to another variation, the hydrodehydrogenation functionality comprises at least one Group VIII element (preferably nickel) and is preferably composed of it. According to this variation, the nickel content of NiO, expressed relative to the weight of the catalyst, is preferably between 1 wt% and 50 wt%, and more preferably between 10 wt% and 30 wt%. This type of catalyst is preferably used in its reduced form on a support, preferably a mineral support, and more preferably on an alumina support.

[0091] The support for the at least one selective hydrogenation catalyst is preferably selected from alumina, silicon dioxide, silicon dioxide-alumina, magnesium oxide, clay, and mixtures thereof. The support may contain other doped compounds, particularly selected from oxides such as boron oxide (specifically boron trioxide), zirconium oxide, cerium dioxide, titanium oxide, phosphorus pentoxide, and mixtures thereof. Preferably, the at least one selective hydrogenation catalyst comprises an alumina support doped with phosphorus and, depending on the situation, boron. When phosphorus pentoxide (P₂O₅) is present, its concentration is less than 10% by weight relative to the weight of alumina and advantageously at least 0.001% by weight relative to the total weight of 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% by weight relative to the total weight of alumina. The alumina used may be, for example, γ (gamma) or η (eta) alumina.

[0092] This selective hydrogenation catalyst is, for example, in extrusion form.

[0093] Preferably, in order to selectively hydrogenate the diene as much as possible, in addition to the selective hydrogenation catalyst described above, step a) may also use at least one selective hydrogenation catalyst used in step a), which comprises 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 the weight of nickel oxide NiO relative to the 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 oxide MoO3 relative to the catalyst, on an alumina support. This catalyst, with a small amount of metal supported, is preferably placed upstream of the selective hydrogenation catalyst described above.

[0094] The content of impurities (specifically, dienes) in the hydrogenated effluent obtained at the end of step a) is lower than the content of the same impurities (specifically, dienes) included in the feedstock used in the process. The selective hydrogenation step a) typically makes it possible to convert at least 30%, and preferably at least 40%, of the dienes contained in the initial feedstock. The hydrogenated effluent obtained at the end of the selective hydrogenation step a) is preferably fed directly to the hydrodemetallization step b).

[0095] [Hydrodemetallization step] [b)] [] According to the present invention, the method comprises a hydrodemetallization step b) performed in a hydrodemetallization reaction section containing at least one hydrodemetallization catalyst, the hydrodemetallization reaction section being fed at least the feedstock containing plastic pyrolysis oil, which has been pretreated as appropriate, and / or the hydrogenated effluent obtained from a), and a gas stream containing hydrogen, the hydrodemetallization reaction section being performed at an average temperature between 140 and 400°C, a hydrogen partial pressure between 1.0 and 20.0 MPa abs., and a space velocity between 0.1 and 10.0 h⁻¹, to obtain a demetallized effluent.

[0096] Depending on the circumstances, the reaction section of step b) may also be fed with at least a portion of pre-treated feedstock derived from renewable resources.

[0097] Depending on the circumstances, the reaction zone of step b) may also be fed with at least a portion of the recycled stream from step d) of the method or, as appropriate, step e).

[0098] Depending on the composition of the raw materials, the conditions for the hydrodemetallization step enable hydrodemetallization reactions (especially the retention of silicon), hydrogenation reactions (especially the hydrogenation of dienes and alkenes), hydrotreatment reactions (especially the conversion of chlorine, nitrogen and sulfur), hydrogenolysis of ester functional groups and / or decarboxylation reactions.

[0099] The hydrodemetallization step b) can be performed in a hydrodemetallization reaction section containing at least one hydrodemetallization catalyst using at least one fluidized bed, entrained bed, moving bed and / or fixed bed reactor.

[0100] According to a preferred model, step b) is carried out in a fixed bed. Step b) in a fixed bed is particularly carried out at the starting point of the hydrodemetallization reaction section under hydrogen pressure and temperature conditions that enable at least partial hydrogenation of the dienes and olefins, especially in the absence of a selective hydrogenation step a), while allowing an increasing temperature distribution such that the outlet temperature of the reaction section of step b) is preferably at least 15°C higher than the inlet temperature of the reaction section of b). In practice, the required amount of hydrogen is injected to allow for the hydrogenation of at least a portion of the dienes and olefins present in the feedstock, the hydrodemetallization of at least a portion of the metals and / or metalloids, especially the retention of silicon, and the conversion of at least a portion of chlorine (to HCl according to the hydrodechlorination mechanism). Therefore, the hydrogenation of the dienes and olefins makes it possible to avoid or at least limit the formation of "gels," i.e., the polymerization of the dienes and olefins and the resulting formation of oligomers and polymers that can clog the reaction section of the hydrotreatment step c). In parallel with hydrogenation, hydrodemetallization, and especially the retention of silicon during step b), it is possible to limit the catalytic deactivation of the reaction section in step c) of the hydrotreatment process. Furthermore, the conditions of step b), particularly the temperature and the increasing temperature distribution, enable the conversion of at least a portion of the chlorine to carry out a portion of the hydrotreatment and thus remove a portion of the nitrogen and sulfur, thereby partially converting triglycerides and / or free fatty acids into hydrocarbon-based molecules via ester functional group decarboxylation and / or hydrogenolysis mechanisms.

[0101] When step b) is carried out in a fixed bed, temperature control is therefore crucial and must meet antagonistic constraints. On the one hand, the inlet and overall temperature of the hydrodemetallization reaction section must be sufficiently low to allow hydrogenation of dienes and olefins at the start of the hydrodemetallization reaction section, especially in the absence of step a), which may be chosen as appropriate. On the other hand, the inlet temperature of the hydrodemetallization reaction section must be sufficiently high to avoid catalyst deactivation induced by impurity deposits at low temperatures. Since hydrogenation reactions, especially the hydrogenation of some olefins and dienes, the decarboxylation and / or hydrogenolysis of ester functional groups are highly exothermic, an increasing temperature distribution is observed in the hydrodemetallization reaction section. This higher temperature at the end of this section makes it possible to perform hydrodemetallization and hydrodechlorination reactions. Therefore, the outlet temperature of the reaction section in step b) is at least 15°C higher than the inlet temperature of the reaction section in step b), preferably at least 25°C higher, and particularly preferably at least 30°C higher.

[0102] The temperature difference between the inlet and outlet of the reaction section in step b) is compatible with any gas (hydrogen) cooling stream or liquid cooling stream injected as appropriate (e.g., recirculation of the stream from steps d) and / or e).

[0103] The temperature difference between the inlet and outlet of the reaction section in step b) is solely due to the exothermic nature of the chemical reaction carried out in the reaction section and is therefore compatible without the use of heating elements (oven, heat exchanger, etc.).

[0104] The inlet temperature of the reaction zone in step b) is between 135 and 385°C, preferably between 210 and 335°C.

[0105] The outlet temperature of the reaction section in step b) is between 150 and 400°C, preferably between 225 and 350°C.

[0106] According to the invention, it is advantageous to carry out, at least partially, the hydrogenation of dienes and olefins, the hydrodemetallization reaction, especially the retention of silicon, and a portion of the hydrotreatment reaction in the same step and at a temperature sufficient to limit the deactivation of the catalyst in step c). This same step also makes it possible to benefit from the heat from the reaction so as to have an increasing temperature distribution in this step and thus eliminate the need for apparatus for heating between the catalytic section of hydrodemetallization and the catalytic section of hydrotreatment.

[0107] In the presence of at least one hydrodemetallization catalyst, the hydrodemetallization is advantageously performed at an average temperature (or WABT as defined in step a) between 140 and 400 °C, preferably between 220 and 350 °C, particularly preferably between 260 and 330 °C, at a hydrogen partial pressure between 1.0 and 20.0 MPa abs., preferably between 1.5 and 15.0 MPa abs., and at a space-time rate (HSV) between 0.1 and 10.0 h⁻¹, preferably between 0.2 and 5.0 h⁻¹, and most preferably between 0.3 and 3.0 h⁻¹.

[0108] The amount of hydrogen (H2) gas feed into the reaction section of step b) is advantageously such that the hydrogen coverage is between 50 and 1000 Nm3 hydrogen / m3 feed (Nm3 / m3), more preferably between 50 and 500 Nm3 hydrogen / m3 feed (Nm3 / m3), and even more preferably between 200 and 300 Nm3 hydrogen / m3 feed (Nm3 / m3). In practice, the amount of hydrogen required to allow at least a portion of the hydrogenation of dienes and olefins, and at least a portion of the hydrogenation and demetallization of metals, especially the retention of silicon, and at least a portion of the conversion of chlorine (to HCl) and, where applicable, at least a portion of the conversion of esters from renewable sources, is greater than the amount of hydrogen required to perform only the hydrogenation of dienes as described in FR20 / 01.758.

[0109] Space velocity (HSV) and hydrogen coverage are defined as described in step a), wherein the “feed entering the reaction zone” is, as appropriate, pretreated (step a0) and selectively hydrogenated (step a)), i.e., all “fresh” feedstock containing at least cracked oil and, as appropriate, some or all of the feedstock derived from renewable resources, supplemented by the recycled stream obtained from steps d) and / or e).

[0110] Advantageously, the reaction section of step b) comprises between 1 and 5 reactors, preferably between 2 and 5 reactors, and especially preferably it comprises two reactors.

[0111] One or more reactors in the reaction section of step b) may be of the type of fixed bed, fluidized bed, entrained bed and / or moving bed reactor.

[0112] According to one variation, the reaction section comprises a fluidized bed reactor or a moving bed reactor that allows for catalyst introduction and removal operations to compensate for deactivation.

[0113] According to another preferred variation, the reaction section includes a fixed-bed reactor, preferably two fixed-bed reactors, each having n catalyst beds, where n is an integer greater than or equal to 1, each containing at least one hydrodemetallization catalyst.

[0114] According to a particular embodiment, all or part of the feedstock can be injected at the inlet of the catalyst bed for each stage to manage exothermic reactions, as described in FR2969642. In this case, the entire feedstock stream is divided into a certain number of distinct streams equal to the number of catalyst beds in the reactor, and the distinct streams are injected at the inlet of the continuous catalyst bed in an increasing proportion.

[0115] According to one variation, the catalytic bed reactor operates in a "PRS" (Plasma Replacement System), also known as a "rocking" fixed-bed displacement mode. A combination of reactors in at least two PRS modes makes it possible to isolate a reactor, discharge spent catalyst, reload the reactor with fresh catalyst, and return the reactor to operation without stopping the process. PRS technology is specifically described in patent FR2681871. The advantage of a hydrodemetallization reaction section comprising several reactors in displacement modes lies in optimized feedstock handling, while simultaneously making it possible to reduce the risk of blockage and / or deactivation of the catalytic bed, thereby avoiding shutdown of the unit due to blockage and / or deactivation.

[0116] According to a particularly preferred variation, the hydrogenation demetallization reaction section of step b) is contained in two reactors operating in a displacement mode.

[0117] Advantageously, reactor inserts of the filter plate type, for example, can be used to prevent reactor clogging. Examples of filter plates are described in patent FR3051375.

[0118] Advantageously, the hydrodemetallization catalyst includes a support (preferably a mineral support) and hydrodehydrogenation functionality.

[0119] According to one variation, the hydrodehydrogenation functionality particularly includes at least one Group VIII element preferably selected from nickel and cobalt, and at least one Group VIB element preferably selected from molybdenum and tungsten. According to this variation, the total content of oxides of Group VIB and Group VIII metal elements, expressed relative to the total weight of the catalyst, is preferably between 1 wt% and 40 wt%, and more preferably between 5 wt% and 30 wt%. 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.

[0120] The weight ratio of metal oxides of Group VIB metals to metal oxides of Group VIII metals is preferably between 1 and 20, and more preferably between 2 and 10.

[0121] According to this variation, the reaction section of step b) includes, for example, a hydrodemetallization catalyst comprising 0.5% to 12% by weight of nickel, preferably 1% to 10% by weight of nickel (in terms of the weight of nickel oxide NiO relative to the catalyst) on a support (preferably a mineral support, preferably an alumina support), and 1% to 30% by weight of molybdenum, preferably 3% to 20% by weight of molybdenum (in terms of the weight of molybdenum oxide MoO3 relative to the catalyst).

[0122] According to another variation, the hydrodehydrogenation functionality comprises at least one Group VIII element (preferably nickel) and is preferably composed of it. According to this variation, the nickel oxide content relative to the weight of the catalyst is preferably between 1 and 50% by weight, and more preferably between 10 and 30% by weight. This type of catalyst is preferably used in its reduced form on a support, preferably a mineral support, and more preferably on an alumina support.

[0123] The support for the hydrodemetallization catalyst is preferably selected from alumina, silicon dioxide, silicon dioxide-alumina, magnesium oxide, clay, and mixtures thereof. The support may contain other doped compounds, particularly selected from oxides such as boron oxide (specifically boron trioxide), zirconium oxide, cerium dioxide, titanium oxide, phosphorus pentoxide, and mixtures thereof. Preferably, the hydrodemetallization catalyst comprises an alumina support doped with phosphorus and, depending on the situation, boron. When phosphorus pentoxide (P₂O₅) is present, its concentration is less than 10% by weight relative to the weight of alumina and advantageously at least 0.001% by weight relative to the total weight of 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% by weight relative to the total weight of alumina. The alumina used may be, for example, γ (gamma) or η (eta) alumina.

[0124] The hydrodemetallization catalyst is, for example, in extrusion form.

[0125] Preferably, step b) can also use at least one hydrodemetallization catalyst used in step b) other than the hydrodemetallization catalyst described above on an alumina support, comprising less than 1 wt% nickel and at least 0.1 wt% nickel, preferably 0.5 wt% nickel (expressed as nickel oxide NiO relative to the catalyst), and less than 5 wt% molybdenum and at least 0.1 wt% molybdenum, preferably 0.5 wt% molybdenum (expressed as molybdenum oxide MoO3 relative to the catalyst). This catalyst, not highly loaded with metal, can preferably be positioned upstream or downstream of the hydrodemetallization catalyst described above, preferably downstream.

[0126] Advantageously, the catalyst used in step b) can be selected from known hydrodemetallization catalysts, hydrotreatment catalysts, or silicon removal catalysts and combinations thereof, particularly for processing petroleum fractions. Known hydrodemetallization catalysts are, for example, those described in patents EP 0113297, EP 0113284, US 5221656, US 5827421, US 7119045, US 5622616, and US 5089463. Known silicon removal catalysts are, for example, those described in patent applications CN 102051202 and US 2007 / 080099.

[0127] The hydrodemetallization step b) makes it possible to obtain a demetallized effluent, i.e., with reduced silicon content and, where applicable, reduced olefins (especially dienes), metals, and chlorine content. Preferably, at least 50% and more preferably at least 75% of the chlorine and silicon in the initial feedstock are removed during step b). The demetallized effluent obtained at the end of the hydrodemetallization step b) is preferably fed directly to the hydrotreating step c).

[0128] [Hydrogenation treatment steps] [c)] [] According to the present invention, the processing method includes a hydrotreating step c), which is carried out in a hydrotreating reaction section containing at least one hydrotreating catalyst, the hydrotreating reaction section being fed at least the demetallized effluent obtained from step b) and a gas stream containing hydrogen, the hydrotreating reaction section being used at a temperature between 250 and 450°C, a hydrogen partial pressure between 1.0 and 20.0 MPa abs., and a space velocity between 0.1 and 10.0 h⁻¹ to obtain the hydrotreating effluent.

[0129] Depending on the circumstances, the reaction zone of step c) may also be fed with at least a portion of pre-treated feedstock derived from renewable resources.

[0130] According to one variation, in step c), at least a portion and preferably all of the raw materials derived from renewable resources are introduced.

[0131] Depending on the circumstances, the reaction zone of step c) may also be fed with at least a portion of the recycled stream from step d) of the method or, as appropriate, step e).

[0132] Advantageously, step c) performs hydrogenation reactions well known to those skilled in the art, and more specifically, hydrogenation reactions such as hydrogenation of aromatic compounds, hydrodesulfurization, and hydrodenitrogenation. Furthermore, hydrogenation of olefins and remaining halogenated compounds and hydrodemetallization are continued. Step c) also performs hydrogenolysis and / or decarboxylation reactions on ester functional groups derived from triglycerides and / or free fatty acids from renewable sources.

[0133] Advantageously, the hydrotreating reaction section is carried out at a pressure equal to that used in the reaction section of the hydrodemetallization step b), but at a higher temperature. Therefore, the hydrotreating reaction section is advantageously carried out at an average hydrotreating temperature between 250 and 450°C, preferably between 280 and 380°C, at a hydrogen partial pressure between 1.0 and 20.0 MPa abs., and at a space time (HSV) between 0.1 and 10.0 h⁻¹, preferably between 0.1 and 5.0 h⁻¹, preferably between 0.2 and 2.0 h⁻¹, and between 0.2 and 1 h⁻¹. The hydrogen coverage in step c) is advantageously between 50 and 1000 Nm³ of hydrogen / m³ feed to the feedstock in step c), more preferably between 50 and 500 Nm³ of hydrogen / m³ feed to the feedstock in step c), and even more preferably between 100 and 300 Nm³ of hydrogen / m³ feed to the feedstock in step c). The definitions of temperature (WABT), HSV, and hydrogen coverage correspond to those described above, wherein the feedstock entering the reaction zone of step c) is obtained from the demetallized effluent of step b) and, where applicable, part or all of the feedstock derived from renewable resources is supplemented by the recycled stream obtained from steps d) and / or e).

[0134] The (average) temperature of the reaction zone in step c) is preferably higher than the (average) temperature of the hydrogenation demetallization reaction zone in step b), preferably at least 10°C higher, and preferably at least 15°C higher.

[0135] The hydrogen-containing gas stream fed into the reaction zone of step c) may consist of hydrogen supplied and / or advantageously obtained from recycled hydrogen in step d) or, as appropriate, step e).

[0136] Advantageously, the reaction section of step c) comprises 1 to 5 reactors, preferably 2 to 5 reactors, and especially preferably two reactors.

[0137] One or more reactors in the reaction section of step c) may be of the type of fixed bed, fluidized bed, entrained bed and / or moving bed reactor.

[0138] According to one variation, the reaction section comprises a fluidized bed reactor or a moving bed reactor that allows for catalyst introduction and removal operations to compensate for deactivation.

[0139] Advantageously, step c) is carried out in a hydrotreatment reaction section comprising at least one, preferably one to five, fixed-bed reactors containing n catalyst beds, where n is an integer greater than or equal to one, preferably between 1 and 10, and preferably between 2 and 5, each of the beds comprising at least one and preferably no more than ten hydrotreatment catalysts. When the reactor comprises several catalyst beds, i.e., at least two, preferably two to ten, preferably two to five catalyst beds, these catalyst beds are preferably arranged in series in the reactor.

[0140] In a preferred embodiment of the present invention, the hydrogenation reaction section comprises a single fixed-bed reactor containing n catalyst beds, where n is an integer greater than or equal to one, preferably between one and ten, and more preferably between two and five.

[0141] According to one embodiment, all or part of the feedstock can be injected at the inlet of the catalyst bed into each stage to manage exothermic reactions, as described above. According to a variation, particularly when feedstock derived from renewable resources is injected in step c), the feedstock (cracked oil) obtained from step b) is introduced at the top of the hydrotreating reaction section c), while feedstock derived from renewable resources is injected into each stage at the inlet of each catalyst bed in an increasing proportion. This makes it possible to manage exothermic reactions more successfully.

[0142] When step c) is performed in a hydrotreatment reaction section comprising several reactors, preferably two reactors, these reactors may be operated in series and / or in parallel and / or in a displacement (or PRS) mode and / or a tumbling mode. Various operating modes, PRS (or tumbling) modes, and tumbling modes, as appropriate, are well known to those skilled in the art and are advantageously defined above.

[0143] Advantageously, the hydrotreating catalyst comprises a support (preferably a mineral support) and at least one metallic element having hydrotreating and dehydrogenating functionality. The metallic element having hydrotreating and dehydrogenating functionality advantageously comprises at least one Group VIII element preferably selected from the group consisting of nickel and cobalt, and / or at least one Group VIB element preferably selected from the group consisting of molybdenum and tungsten. The total content of oxides of Group VIB and Group VIII metallic elements relative to the total weight of the catalyst is preferably between 0.1 wt% and 40 wt%, and more preferably between 5 wt% and 35 wt%. 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 of metal oxides representing Group VIB metals to metal oxides representing Group VIII metals is preferably between 1.0 and 20, and more preferably between 2.0 and 10. For example, the hydrotreating reaction section of step b) of the method includes a hydrotreating catalyst comprising 0.5% to 10% by weight of nickel, preferably 1% to 8% by weight of nickel (represented as total weight of nickel oxide NiO relative to the hydrotreating catalyst) on a mineral support (preferably an alumina support), and 1.0% to 30% by weight of molybdenum, preferably 3.0% to 29% by weight of molybdenum (represented as total weight of molybdenum oxide MoO3 relative to the hydrotreating catalyst).

[0144] The support for the hydrotreating catalyst is advantageously selected from alumina, silicon dioxide, silicon dioxide-alumina, magnesium oxide, clay, and mixtures thereof. The support may also contain other doped compounds, particularly selected from oxides such as boron oxide (specifically boron trioxide), zirconium oxide, cerium dioxide, titanium oxide, phosphorus pentoxide, and mixtures thereof. Preferably, the hydrotreating catalyst comprises an alumina support, more preferably an alumina support doped with phosphorus and, where appropriate, boron. When phosphorus pentoxide (P₂O₅) is present, its concentration is less than 10% by weight relative to the weight of alumina and advantageously at least 0.001% by weight relative to the total weight of 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% by weight relative to the total weight of alumina. The alumina used may be, for example, γ (gamma) or η (eta) alumina.

[0145] The hydrotreating catalyst is, for example, in extrusion form.

[0146] Known hydrogenation catalysts are those described in, for example, patents EP0113297, EP0113284, US6589908, US4818743 or US6332976.

[0147] Advantageously, the hydrotreating catalyst used in step c) of this method has a specific surface area greater than or equal to 250 m² / g, preferably greater than or equal to 300 m² / g. The specific surface area of ​​the hydrotreating catalyst is advantageously less than or equal to 800 m² / g, preferably less than or equal to 600 m² / g, and particularly less than or equal to 400 m² / g. The specific surface area of ​​the hydrotreating catalyst is measured by the BET method, i.e., by nitrogen adsorption according to the standard ASTM D 3663-78, derived from the Brunauer-Emmett-Teller method described in the periodic journal *The Journal of the American Chemical Society*, 60, 309 (1938). This specific surface area may further improve the removal of contaminants (specifically, metals such as silicon).

[0148] According to another aspect of the invention, the hydrotreating catalyst described above also comprises one or more organic compounds containing oxygen and / or nitrogen and / or sulfur. This catalyst is generally referred to by the term "additive catalyst". Generally, the organic compound is selected from compounds with chemical functions selected from: carboxylic acids, alcohols, thiols, thioethers, sulfides, sulfides, sulfides, ethers, aldehydes, ketones, esters, carbonates, amines, nitriles, amides, oximes, ureas, and amides, or other compounds including furan rings or sugars.

[0149] Since the feedstocks from renewable sources contain very little or no sulfur, depending on the sulfur content of the feedstocks derived from plastic pyrolysis, it is advantageous to inject sulfur-containing compounds (e.g., DMDS) to maintain the active phase of the catalyst in thioether form. Sulfur-containing compounds can also be added to the catalysts in other steps (steps a), b), and / or c').

[0150] Advantageously, the hydrotreating step c) allows for the hydrotreating of at least 80% of the nitrogen remaining after the hydrodemetallization step b), and the conversion of at least 80% of the triglycerides. Step c) also allows for the partial removal of other impurities present in the feedstock, such as aromatic compounds, metal compounds, sulfur-containing compounds, nitrogen-containing compounds, halogenated compounds (especially chlorinated compounds), or oxygen-containing compounds. Preferably, the nitrogen content at the output of step c) is less than 10 ppm by weight. Step c) also allows for further reduction of contaminants, such as metals, especially silicon. Preferably, the metal content at the output of step c) is less than 10 ppm by weight and the silicon content is less than 5 ppm by weight.

[0151] [Hydrocracking Step] [c')] [(] [Select as needed] [)] [] According to one variation, the method of the present invention may include a hydrocracking step c' performed directly after the hydrotreating step c) or after the fractionation step e) on a hydrocarbon fraction containing compounds with a boiling point greater than 175°C.

[0152] Advantageously, step c') carries out a hydrocracking reaction well known to those skilled in the art, and more specifically, makes it possible to convert heavy compounds, such as those with boiling points greater than 175°C, into compounds with boiling points less than or equal to 175°C, which are contained in the hydrotreated effluent obtained from step c) or separated during a fractionation step e), if appropriate. Other reactions can then be carried out, such as hydrogenation of olefins or aromatics, hydrodemetallization, hydrodesulfurization, hydrodenitrogenation, etc.

[0153] Compounds with boiling points above 175°C have high BMCI and contain more cycloalkanes, cycloalkanes, and aromatics compared to lighter compounds, resulting in a higher C / H ratio. This high ratio leads to coking in the steam cracker, thus requiring a dedicated steam cracker for this fraction. When it is necessary to minimize the yield of these heavy compounds (diesel fraction) and maximize the yield of light compounds (naphtha fraction), these compounds can be converted into lighter compounds, at least partially, by hydrocracking, a process generally advantageous for steam cracking units.

[0154] Therefore, the method of the present invention may include a hydrocracking step c') performed in a hydrocracking reaction section comprising at least one hydrocracking catalyst, the hydrocracking reaction section being fed with the hydrotreated effluent obtained from step c) and / or a fraction containing compounds with a boiling point greater than 175°C and a gas stream containing hydrogen obtained from step e), the hydrocracking reaction section being operated at an (average) temperature between 250 and 450°C, a hydrogen partial pressure between 1.5 and 20.0 MPa abs., and a space velocity between 0.1 and 10.0 h⁻¹, to obtain the hydrocracking effluent to be conveyed to separation step d).

[0155] Therefore, the hydrocracking reaction section is advantageously carried out at a hydrocracking temperature between 250°C and 450°C, preferably between 320°C and 440°C, at a hydrogen partial pressure between 1.5 and 20.0 MPa abs., preferably between 2 and 18.0 MPa abs., and at a space velocity (HSV) 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 c') is advantageously between 80 and 2000 Nm³ of hydrogen / m³ of feed to the feedstock in step c'), and preferably between 200 and 1800 Nm³ of hydrogen / m³ of feed to the feedstock in step c'). Temperature (WABT), HSV, and hydrogen coverage correspond to those described above, wherein the hydrogenated effluent obtained from step c) and / or the hydrocarbon fraction containing compounds with boiling points greater than 175°C obtained from step e) are used as "feeds to the reaction zone of step c').

[0156] Advantageously, the hydrocracking reaction section is carried out at a pressure equal to the pressure used in the reaction section of the hydrodemetallization step b) or the hydrotreatment step c). According to another variation, the hydrocracking reaction section is carried out at a pressure equal to the pressure used in the reaction section of the hydrodemetallization step b) or the hydrotreatment step c).

[0157] One or more reactors in the reaction section of step c') may be of the type of fixed bed, fluidized bed, entrained bed and / or moving bed reactor, preferably of the type of fixed bed.

[0158] Advantageously, step c') is performed in a hydrocracking reaction section comprising at least one, preferably one to five, fixed-bed reactors containing n catalyst beds, where n is an integer greater than or equal to one, preferably between one and ten, and preferably between two and five, each of the beds comprising at least one and preferably no more than ten hydrocracking catalysts. When the reactor comprises several catalyst beds, i.e., at least two, preferably two to ten, and preferably two to five catalyst beds, these catalyst beds are preferably arranged in series in the reactor.

[0159] The hydrotreating step c) and the hydrocracking step c') can advantageously be performed in the same reactor or in different reactors. When performed in the same reactor, the reactor comprises several catalyst beds, the first catalyst bed containing a hydrotreating catalyst and subsequent catalyst beds containing a hydrocracking catalyst.

[0160] The hydrocracking step can be performed in one step (step c') or in two steps (steps c' and c''). When performed in two steps, fractionation is carried out on the effluent obtained from the first hydrocracking step c'), making it possible to obtain a fraction (diesel fraction) containing compounds with boiling points greater than 175°C during steps d) and e), which is then introduced into a second hydrocracking step c'') containing a dedicated second hydrocracking reaction section different from the first hydrocracking reaction section c'). This configuration is particularly suitable when maximizing naphtha fraction is required.

[0161] In the hydrocracking reaction section, a second hydrocracking step c'' is performed using at least one fixed bed containing n catalyst beds (n being an integer greater than or equal to 1), each containing at least one hydrocracking catalyst. The hydrocracking reaction section is fed at least a fraction from step e) containing compounds with boiling points greater than 175°C and a gas stream containing hydrogen. The hydrocracking reaction section is operated at an average temperature between 250 and 450°C, a hydrogen partial pressure between 1.5 and 20.0 MPa abs., and a space velocity between 0.1 and 10.0 h⁻¹ to obtain the hydrocracking effluent to be conveyed to separation step d). 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 steps may be the same or different.

[0162] The second hydrocracking step is preferably performed in a hydrocracking reaction section of a fixed-bed reactor containing at least one, preferably one to five, n catalyst beds, where n is an integer greater than or equal to one, preferably one to ten, and preferably two to five, and each of the beds contains at least one and preferably no more than ten hydrocracking catalysts.

[0163] The operating conditions used in one or more hydrocracking steps generally enable a single-pass conversion to a product having at least 80% by volume of a compound with a boiling point less than or equal to 175°C, preferably less than 160°C and more preferably less than 150°C, and greater than 15% by weight, and even more preferably between 20% and 95% by weight. When the method is performed with two hydrocracking steps, the single-pass conversion in the second step is kept moderate to maximize selectivity for compounds in the naphtha fraction (boiling point less than or equal to 175°C, specifically between 80% and 175°C). This recycling ratio is defined as the ratio between the flow rate of the compound with a boiling point greater than 175°C obtained from step e) and the flow rate of the feedstock from step c); preferably, this ratio is between 0.2 and 4, and more preferably between 0.5 and 2.5.

[0164] Therefore, the hydrocracking step does not necessarily require converting all compounds with boiling points greater than 175°C (diesel fraction) into compounds with boiling points less than or equal to 175°C (naphtha fraction). After fractionation step e), a substantially significant proportion of compounds with boiling points greater than 175°C can thus be retained. To improve conversion, at least a portion of this unconverted fraction can be recycled to step c') as described below or additionally fed to a second hydrocracking step c''). Another portion can be purged. Depending on the operating conditions of the method, this purging, relative to the feedstock, can be between 0 and 10 wt%, and preferably between 0.5 and 5 wt%, of a fraction containing compounds with boiling points greater than 175°C.

[0165] According to the present invention, the hydrocracking step is carried out in the presence of at least one hydrocracking catalyst.

[0166] The hydrocracking catalyst used in the hydrocracking step is a known hydrocracking catalyst of the bifunctional type, characterized by a combination of acid functionality and hydrodehydrogenation functionality, and, where applicable, at least one binder matrix. Acid functionality is provided by a support with a large surface area (typically 150 to 800 m² / g) exhibiting surface acidity, such as halogenated (especially chlorinated or fluorinated) alumina, combinations of boron and alumina, amorphous silica-alumina, and zeolites. Hydrodehydrogenation functionality is provided by at least one Group VIB metal and / or at least one Group VIII metal from the periodic table.

[0167] Preferably, the hydrocracking catalyst includes hydrodehydrogenation functionality, comprising at least one Group VIII metal selected from iron, cobalt, nickel, ruthenium, rhodium, palladium, and platinum, and more preferably cobalt and nickel. Preferably, the catalyst also comprises at least one Group VIB metal selected from chromium, molybdenum, and tungsten, either alone or in mixtures, and more preferably molybdenum and tungsten. Hydrodehydrogenation functionality of the NiMo, NiMoW, or NiW type is preferred.

[0168] Preferably, the content of Group VIII metals in the hydrocracking catalyst is advantageously between 0.5% by weight and 15% by weight, and more preferably between 1% by weight and 10% by weight, where the percentage is expressed as a weight percentage of the oxide 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.

[0169] Preferably, the content of Group VIB metals in the hydrocracking catalyst is advantageously between 5% by weight and 35% by weight, and more preferably between 10% by weight and 30% by weight, where the percentage is expressed as a weight percentage of the oxide 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.

[0170] The hydrocracking catalyst may also include, where appropriate, at least one promoter element deposited on the catalyst and selected from the group consisting of phosphorus, boron and silicon, at least one group VIIA element (preferably chlorine and fluorine), at least one group VIIB element (preferably manganese), and at least one group VB element (preferably niobium).

[0171] Preferably, the hydrocracking catalyst comprises an amorphous or poorly crystalline porous mineral matrix selected from alumina, silicon dioxide, silicon dioxide-alumina, aluminates, alumina-boron oxide, magnesium oxide, silicon dioxide-magnesium oxide, zirconium oxide, titanium oxide, or clay, and more preferably selected from at least one oxide type of alumina or silicon dioxide-alumina, either alone or in mixtures.

[0172] Preferably, the silica-alumina contains more than 50% by weight of alumina, more preferably more than 60% by weight of alumina.

[0173] Preferably, the hydrocracking catalyst also includes, where appropriate, a zeolite selected alone or in combination with other zeolites, of which Y zeolite (preferably USY zeolite): β zeolite alone or in mixtures, ZSM-12 zeolite, IZM-2 zeolite, ZSM-22 zeolite, ZSM-23 zeolite, SAPO-11 zeolite, ZSM-48 zeolite, or ZBM-30 zeolite. Preferably, the zeolite is a single USY zeolite.

[0174] When the catalyst contains zeolite, the zeolite content in the hydrocracking catalyst is advantageously between 0.1% by weight and 80% by weight, more preferably between 3% by weight and 70% by weight, the percentage being expressed as a percentage of the total weight of zeolite relative to the catalyst.

[0175] The preferred catalyst comprises, and preferably consists of, at least one Group VIB metal and, where appropriate, at least one Group VIII non-precious metal, at least one promoter element (preferably phosphorus), at least one Y zeolite, and at least one alumina binder.

[0176] The preferred catalyst comprises nickel, molybdenum, phosphorus, USY zeolite (and, in some cases, β-zeolite) and alumina, and preferably consists of each of the above.

[0177] Another preferred catalyst comprises nickel, tungsten, alumina, and silicon dioxide-alumina, and preferably consists of each of the above.

[0178] Another preferred catalyst includes nickel, tungsten, USY zeolite, alumina, and silica-alumina, and preferably consists of each of the above.

[0179] The hydrocracking catalyst is, for example, in extrusion form.

[0180] In one variation, the hydrocracking catalyst used in step c'') comprises hydrodehydrogenation functionality, containing at least one Group VIII noble metal selected from palladium and platinum, either alone or in mixtures. The content of the Group VIII noble metal is advantageously between 0.01 wt% and 5 wt%, and more preferably between 0.05 wt% and 3 wt%, expressed as a weight percentage of the oxide (PtO or PdO) relative to the total weight of the catalyst.

[0181] According to another aspect of the invention, the hydrocracking catalyst described above also comprises one or more organic compounds containing oxygen and / or nitrogen and / or sulfur. This catalyst is generally referred to by the term "additive catalyst". Generally, the organic compound is selected from compounds with chemical functions selected from: carboxylic acids, alcohols, thiols, thioethers, sulfides, sulfides, sulfides, ethers, aldehydes, ketones, esters, carbonates, amines, nitriles, amides, oximes, ureas, and amides, or other compounds including furan rings or sugars.

[0182] The preparation of catalysts used in steps a), b), c), c'), or c'') is known and generally involves impregnating a Group VIII metal and a Group VIB metal (if present) and, where appropriate, phosphorus and / or boron onto a support, followed by drying, and subsequently calcination, where appropriate. For additive catalysts, preparation is generally carried out by simple drying without calcination after the introduction of the organic compound. The term "calcination" herein means heat treatment at a temperature greater than or equal to 200°C in a gas containing air or oxygen. The catalyst generally undergoes sulfidation to form the active material before being used in the process steps. The catalyst in step a) can also be a catalyst used in its reduced form, and therefore its preparation involves a reduction step.

[0183] The hydrogen-containing gas stream fed into reaction sections a), b), c), c'), or c'') can consist of hydrogen supplied and / or advantageously obtained from recycled hydrogen from step d) or, if appropriate, step e). Preferably, another hydrogen-containing gas stream is advantageously introduced into the inlet of each reactor, particularly those operating in series, and / or from the inlet of each catalyst bed of the second catalyst bed in the reaction section. This additional gas stream is also referred to as a cooling stream. The cooling stream controls the temperature in the hydrocracking reactor, where the reaction is typically highly exothermic.

[0184] Depending on the circumstances, each of steps a), b), c), c'), or c'') may use a heating section located upstream of the reaction section, wherein the incoming effluent is heated to a suitable temperature. This heating section, chosen as appropriate, may therefore include one or more heat exchangers, preferably allowing heat exchange between the hydrotreated effluent and / or the hydrocracking effluent and the feedstock to steps b), c), and c'), and / or a preheating oven.

[0185] However, performing step b) at a relatively high temperature in an increasing distribution may, as appropriate, eliminate the need for a heating device or at least reduce the thermal requirements between the hydrodemetallization catalytic section of step b) and the hydrotreatment catalytic section of step d).

[0186] [Separation Steps]d [)] [] According to the invention, the processing method includes a separation step d) advantageously performed in at least one washing / separation section, wherein the feed consists at least of a hydrotreated effluent obtained from step c) or a hydrocracked effluent obtained from steps c') and c'') as selected, and an aqueous solution, to obtain at least one gaseous effluent, an aqueous effluent, and a hydrocarbon-based effluent.

[0187] The gas effluent obtained at the end of step d) advantageously contains hydrogen, preferably at least 80% by volume, more preferably at least 85% by volume. Advantageously, the gas effluent can be at least partially recycled to the selective hydrogenation step a) and / or the hydrodemetallization step b) and / or the hydrotreatment step c) and / or the hydrocracking step c') and / or the hydrocracking step c'').

[0188] The aqueous effluent obtained at the end of step d) advantageously contains ammonium salts and / or hydrochloric acid.

[0189] This separation step d) particularly removes ammonium chloride salts formed through a reaction between chloride ions (released by hydrogenation of chlorinated compounds, particularly in the form of HCl, during step c) and ammonium ions (generated by hydrogenation of nitrogen-containing compounds, particularly in the form of NH3, during step c) and / or by injection of amines, which then dissolve in water). This limits the risk of blockage due to ammonium chloride precipitation in the transfer lines and / or sections and / or transfer lines leading to the steam cracker, particularly in the method of the present invention. Hydrochloric acid formed by the reaction of hydrogen and chloride ions can also be removed.

[0190] Depending on the content of chloride compounds in the initial feedstock to be treated, a stream containing amines (e.g., monoethanolamine, diethanolamine, and / or monodiethanolamine) can be injected upstream of or between the selective hydrogenation step a) and / or the hydrodemetallization step b) and / or the hydrotreatment step c) and / or the hydrocracking step c') and / or the separation step d), preferably upstream of the hydrotreatment step c), to ensure a sufficient amount of ammonium ions combine with the chloride ions formed during the hydrotreatment step c), thus making it possible to limit the formation of hydrochloric acid and therefore limit corrosion downstream of the separation section.

[0191] Advantageously, separation step d) includes injecting an aqueous solution, preferably water, upstream of the washing / separation section into the hydrotreated effluent obtained from step c) or, as appropriate, the hydrocracked effluent obtained from steps c') and c''), in order to at least partially dissolve ammonium chloride and / or hydrochloric acid and thus improve the removal of chlorinated impurities and reduce the risk of clogging caused by the accumulation of ammonium chloride.

[0192] Separation step d) is advantageously carried out at a temperature between 50 and 450°C, preferably between 100 and 440°C, and more preferably between 200 and 420°C. It is crucial to perform this step within this temperature range (and therefore without overcooling the effluent from step c) due to the risk of blockage in the pipeline caused by ammonium chloride precipitation)

[0193] The washing / separation section of step d) may be performed at least in part in a common or separate washing and separation unit, which is well known (separation vessel, pump, heat exchanger, washing column, etc. that can operate at various pressures and temperatures).

[0194] In one embodiment of the invention, which may be chosen as appropriate, separation step d) comprises injecting an aqueous solution into the hydrogenated effluent obtained from step c), followed by a washing / separation section, which advantageously includes a separation stage for obtaining at least one aqueous effluent carrying an ammonium salt, a washed hydrocarbon-based liquid effluent, and a partially washed gaseous effluent. The aqueous effluent carrying the ammonium salt and the washed hydrocarbon-based liquid effluent can then be separated in a decanter to obtain the hydrocarbon-based effluent and the aqueous effluent. The partially washed gaseous effluent can be introduced in parallel into a washing column, in which the effluent preferably has a countercurrent circulation of an aqueous stream with properties similar to that of the aqueous solution injected into the hydrogenated effluent, making it possible to at least partially and preferably completely remove hydrochloric acid and CO2 contained in the partially washed gaseous effluent and thereby obtain the gaseous effluent preferably substantially containing hydrogen and an acidic aqueous stream. The aqueous effluent from the decanter may be mixed with the acidic aqueous stream, and may be used in a mixture with the acidic aqueous stream in a water recirculation loop, to be fed into the aqueous solution upstream of the washing / separation section and / or into the aqueous stream in the washing column in separation step d). The water recirculation loop may include the supply of water and / or alkaline solution, and / or for purging to remove dissolved salts.

[0195] The purification of hydrogen-containing gaseous effluents can be performed using known techniques (purging, amine washing, pressure swing adsorption, or PSA, etc.). Preferably, the purification of hydrogen-containing gaseous effluents is performed at least by means of an amine washing column capable of at least partially removing carbon dioxide formed during the decarboxylation of ester functional groups from a renewable source. Monoethanolamine, diethanolamine, and / or monodiethanolamine are examples of amines that can be used in columns for washing gases.

[0196] In another, optionally chosen, embodiment of the invention, separation step d) may advantageously be included in a "high-pressure" scrubbing / separation section at pressures close to those of selective hydrogenation step a) and / or hydrodemetallization step b) and / or hydrotreatment step c) and / or, optionally, hydrocracking step c'), preferably operating between 1.0 and 20.0 MPa to facilitate hydrogen recirculation. This optionally chosen "high-pressure" section of step d) may be completed in a "low-pressure" section to obtain a hydrocarbon-based liquid fraction that does not contain the gas dissolved under high pressure and is intended to be processed directly during steam cracking or, optionally, fed to fractionation step e).

[0197] The gas fraction obtained from separation step d) may undergo additional purification and separation in order to recover at least one hydrogen-rich gas and / or light hydrocarbons, particularly ethane, propane and butane, which can be recycled upstream of steps a) and / or b) and / or c) and / or c') and / or c''), which may be advantageously transported separately or in mixture form to one or more furnaces in steam cracking step f) in order to increase the overall yield of olefins.

[0198] The hydrocarbon-based effluent obtained from separation step d) is partially or entirely fed directly to the inlet of the steam cracking unit, or to a fractionation step e, as appropriate. Preferably, the hydrocarbon-based liquid effluent is partially or entirely (preferably all) fed to fractionation step e.

[0199] [Fracturing Steps] [e) (] [Select as needed] [)] The method of the present invention may include fractionation of all or part of step d), preferably all of the hydrocarbon-based effluents to obtain at least one gas stream and at least two hydrocarbon-based liquid streams, the two hydrocarbon-based liquid streams being at least one naphtha fraction containing compounds with a boiling point less than or equal to 175°C, particularly between 80 and 175°C, and a hydrocarbon fraction containing compounds with a boiling point greater than 175°C.

[0200] Step e) can in particular remove gases (e.g., ammonia), hydrogen sulfide, and light hydrocarbons containing 1 to 4 carbon atoms dissolved in hydrocarbon-based liquid effluents.

[0201] The fractionation step e) may be selected as appropriate and is preferably performed at a pressure of less than or equal to 1.0 MPa abs., preferably between 0.1 and 1.0 MPa abs.

[0202] According to one embodiment, step e) can be performed in a section advantageously comprising at least one stripping tower equipped with a reflux loop including a reflux vessel. The stripping tower is fed with a hydrocarbon-based liquid effluent obtained from step d) and a vapor stream. The hydrocarbon-based liquid effluent obtained from step d) may be heated before entering the stripping tower, if appropriate. Thus, the lightest compounds are entrained to the top of the column and into the reflux loop including the reflux vessel, where gas / liquid separation is performed. A gas phase containing light hydrocarbons is drawn from the reflux vessel as a gas stream. Advantageously, a naphtha fraction containing compounds with a boiling point less than or equal to 175°C is drawn from the reflux vessel. Advantageously, a hydrocarbon fraction containing compounds with a boiling point greater than 175°C is drawn from the bottom of the stripping tower.

[0203] According to other embodiments, the fractionation step e) may involve both a stripping column and a distillation column, or only the distillation column.

[0204] Naphtha fractions containing compounds with boiling points less than or equal to 175°C and fractions containing compounds with boiling points greater than 175°C, depending on the situation, may be entirely or partially fed to a steam cracking unit, whereby olefins may be (re)formed at the outlet of the steam cracking unit to participate in polymer formation. Preferably, only a portion of such fractions is fed to the steam cracking unit; at least a portion of the remaining portion is recycled to at least one of the steps in the method and / or fed to a fuel storage unit derived from a known petroleum-based feedstock, such as a naphtha storage unit, a diesel storage unit, or a kerosene storage unit.

[0205] According to a preferred embodiment, naphtha fractions containing compounds with a boiling point less than or equal to 175°C are completely or partially fed to a steam cracking unit, while fractions containing compounds with a boiling point greater than 175°C are recycled to steps a) and / or b) and / or c) and / or c') and / or fed to a fuel storage unit.

[0206] In a particular embodiment, the fractionation step e) selected as appropriate may result in, in addition to the gas stream, a naphtha fraction containing compounds with boiling points less than or equal to 175°C, preferably between 80°C and 175°C, a diesel fraction containing compounds with boiling points greater than 175°C and less than 385°C, and a hydrocarbon fraction containing compounds with boiling points greater than or equal to 385°C, referred to as a heavy hydrocarbon fraction. The naphtha fraction may be completely or partially fed to a steam cracking unit and / or to a storage unit of a naphtha pool obtained from a conventional petroleum-based feedstock; it may also be recycled; the diesel fraction may also be completely or partially fed to a steam cracking unit or to a diesel pool obtained from a conventional petroleum-based feedstock, or may additionally be recycled; the heavy fraction may, in itself, be at least partially fed to a steam cracking unit, or may be recycled, particularly in step c') or step c'').

[0207] In another specific embodiment, the naphtha fraction obtained from step e) containing compounds with a boiling point less than or equal to 175°C is fractionated into a heavy naphtha fraction containing compounds with a boiling point between 80 and 175°C and a light naphtha fraction containing compounds with a boiling point less than 80°C. At least a portion of the heavy naphtha fraction is fed into an aromatic complex unit including at least one naphtha reforming step to produce aromatic compounds. According to this embodiment, at least a portion of the light naphtha fraction is fed into the steam cracking step f) described below.

[0208] The gas fraction obtained from fractionation step e) can undergo additional purification and separation to recover at least light hydrocarbons, especially ethane, propane and butane, which can be advantageously separated or transported in a mixture to a furnace in steam cracking step f) to increase the overall yield of olefins.

[0209] [] [Including boiling points greater than]

[0175] [℃] [Of] [Recycling of Compound Fractions] [] At least a portion of the fraction containing compounds with boiling points greater than 175°C from fractionation step e) can be recovered to form a recirculation stream fed upstream of or directly into at least one of the reaction steps of the method of the present invention (especially selective hydrogenation step a) and / or hydrodemetallization step b) and / or hydrotreatment step c) and / or hydrocracking step c') and / or hydrocracking step c''). Depending on the circumstances, a portion of the recirculation stream may be fed to step a0).

[0210] The recirculated stream can be fed into the reactant step a) and / or b) and / or c) and / or c') and / or c'') in a single injection, or it can be divided into several fractions and fed into each reaction step in several injections, that is, fed into different catalyst beds.

[0211] Advantageously, the amount of the recirculated stream containing compounds with boiling points greater than 175°C is adjusted such that the weight ratio of the recirculated stream to the feedstock containing plastic pyrolysis oil and the feedstock from renewable sources (i.e., the feedstock to be processed throughout the process) is less than or equal to 10, preferably less than or equal to 5, and more preferably greater than or equal to 0.001, more preferably greater than or equal to 0.01, and more preferably greater than or equal to 0.1. Most preferably, the amount of the recirculated stream is adjusted such that the weight ratio of the recirculated stream to the feedstock containing plastic pyrolysis oil and the feedstock from renewable sources is between 0.2 and 5.

[0212] According to a preferred variation, when present, at least a portion of the fraction obtained from fractionation step e) containing compounds with boiling points greater than 175°C is fed to hydrocracking step c').

[0213] According to another preferred variation, when present, at least a portion of the fraction obtained from fractionation step e) containing compounds with boiling points greater than 175°C is fed to the second hydrocracking step c'').

[0214] A portion of the fraction containing compounds with boiling points greater than 175°C is recycled to at least one of the reaction steps of the method of the present invention or upstream of at least one of the reaction steps of the method of the present invention, particularly to the hydrocracking steps c') and / or c''), which advantageously increases the yield of naphtha fractions with boiling points less than 175°C. Recycling also dilutes impurities and controls the temperature in the highly exothermic reaction steps involved.

[0215] A purging system can be installed for the recirculation of fractions containing compounds with boiling points greater than 175°C. Depending on the operating conditions of the method, the purging can be 0 to 10% by weight of the fraction containing compounds with boiling points greater than 175°C relative to the incoming feed, and preferably 0.5% to 5% by weight.

[0216] [] [Originated from steps] [d)] [Based on hydrocarbon effluents and] [ / ] [Or obtained from the steps] [e)] [its boiling point is less than or equal to]

[0175] [℃] [Recycling of naphtha fractions] [, , ] A portion of the hydrocarbon-based effluent obtained from separation step d) or a portion of the naphtha fraction with a boiling point less than or equal to 175°C obtained from a fractionation step e) selected as appropriate may be recovered to form a recirculation stream. This recirculation stream is fed upstream of at least one of the reaction steps of the method of the present invention or directly to at least one of the reaction steps of the method of the present invention, particularly to the selective hydrogenation step a) and / or the hydrodemetallization step b) and / or the hydrotreatment step c). Depending on the circumstances, a portion of the recirculation stream may be fed to a pretreatment step a0 selected as appropriate.

[0217] Preferably, at least a portion of the hydrocarbon-based effluent obtained from separation step d) or the naphtha fraction with a boiling point less than or equal to 175°C obtained from a fractionation step e) selected as appropriate is fed into hydrotreating step c).

[0218] Advantageously, the amount of the recirculated stream (i.e., the portion of the obtained recycled product) is adjusted such that the weight ratio of the recirculated stream to the feedstock containing the plastic pyrolysis oil and the feedstock from the renewable source (i.e., the feedstock to be processed throughout the process) is less than or equal to 10, preferably less than or equal to 5, and more preferably greater than or equal to 0.001, more preferably greater than or equal to 0.01, and more preferably greater than or equal to 0.1. Most preferably, the amount of the recirculated stream is adjusted such that the weight ratio of the recirculated stream to the feedstock containing the plastic pyrolysis oil and the feedstock from the renewable source is between 0.2 and 5.

[0219] Advantageously, in the initial stages of the process, the hydrocarbon fraction outside the process can be used as a recycle stream. Those skilled in this technique will subsequently learn how to select this hydrocarbon fraction.

[0220] Recycling a portion of the obtained product to at least one of the reaction steps of the method of the present invention or upstream of at least one of the reaction steps of the method of the present invention advantageously makes it possible to first dilute impurities and secondly control the temperature in the reaction step in which the reaction involved is highly exothermic.

[0221] Therefore, the hydrocarbon-based effluent or the hydrocarbon-based stream obtained by processing plastic pyrolysis oil and feedstock from renewable sources according to the method of the present invention has a composition compatible with the specifications of the feedstock entering the steam cracking unit. Specifically, the composition of the hydrocarbon-based effluent or the hydrocarbon-based stream (etc.) is preferably such that: - The total content of metallic elements is less than or equal to 5.0 ppm by weight, preferably less than or equal to 2.0 ppm by weight, more preferably less than or equal to 1.0 ppm by weight, and even more preferably less than or equal to 0.5 ppm by weight, wherein: The silicon (Si) content is less than or equal to 1.0 ppm by weight, preferably less than or equal to 0.6 ppm by weight, and The iron (Fe) content is less than or equal to 100 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 oxygen content is less than or equal to 0.5% by weight, preferably less than or equal to 0.1% 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, and even more preferably less than or equal to 5 ppm by weight. - The content of asphaltene is less than or equal to 5.0 ppm by weight. - The total chlorine content, by weight, is less than or equal to 10 ppm, preferably less than 1.0 ppm by weight. - The content of olefin compounds (monoolefins and dienes) is less than or equal to 5.0 wt%, preferably less than or equal to 2.0 wt%, and more preferably less than or equal to 0.1 wt%.

[0222] The content is given relative to the total weight of the stream under consideration as a relative weight concentration, weight percentage (%), weight parts per million (ppm), or weight parts per billion (ppb).

[0223] Therefore, the method of the present invention can process plastic pyrolysis oil and raw materials from renewable sources together to obtain effluents that can be wholly or partially injected into a steam cracking unit.

[0224] [Steam pyrolysis step] [f) (] [Select as needed] [)] [] The hydrocarbon-based effluent obtained from separation step d) or at least one of the two hydrocarbon-based liquid streams obtained from step e) (as appropriate) can be completely or partially transported to steam cracking step f).

[0225] Advantageously, all or part of the gas fraction obtained from separation step d) and / or fractionation step e) and containing ethane, propane and butane can also be transported to steam cracking step f).

[0226] The steam cracking step f) is advantageously performed in at least one pyrolysis furnace at a temperature between 700 and 900°C, preferably between 750 and 850°C, and at a relative pressure between 0.05 and 0.3 MPa. The residence time of the hydrocarbon-based compound is typically less than or equal to 1.0 second (denoted as s), preferably between 0.1 and 0.5 s. Steam is advantageously introduced upstream of the steam cracking step f) and after separation (or fractionation), as appropriate. The amount of water introduced in steam form is advantageously between 0.3 and 3.0 kg water / kg of hydrocarbon-based compound entering step f). Step f) is preferably performed in a plurality of parallel pyrolysis furnaces, thereby adapting the operating conditions to the various streams fed to step f) and, in particular, from step e), and to managing the decoking time in the piping. The furnace comprises one or more piping arranged in parallel. The furnace may also refer to a group of furnaces operating in parallel. For example, the furnace can be specifically used for cracking naphtha fractions containing compounds with a boiling point of less than or equal to 175°C.

[0227] Generally, the effluents from various steam cracking furnaces are recombined prior to separation to form the effluent. It should be understood that the steam cracking step f) includes the steam cracking furnace and, more importantly, sub-steps associated with steam cracking known to those skilled in the art. These sub-steps may include, in particular, heat exchangers, tubular columns and catalytic reactors, and steps for recycling back to the furnace. The tubular column can generally fractionate the effluent to recover at least one light fraction containing hydrogen and compounds containing 2 to 5 carbon atoms, a fraction containing pyrolysis gasoline, and, where applicable, a fraction containing pyrolysis oil. The tubular column can separate and fractionate the various components of the light fraction to recover at least one ethyl-rich fraction (C2 fraction) and a propylene-rich fraction (C3 fraction), and, where applicable, a butene-rich fraction (C4 fraction). The catalytic reactor can particularly perform the hydrogenation of the C2, C3, or even C4 fractions and pyrolysis gasoline. It is advantageous to recycle saturated compounds (especially those containing 2 to 4 carbon atoms) back to the steam cracking furnace to increase the overall yield of olefins.

[0228] This steam cracking step f) makes it possible to obtain an effluent containing at least one olefin comprising 2, 3, and / or 4 carbon atoms (i.e., C2, C3, and / or C4 olefins) in a satisfactory weight relative to the steam cracking effluent in question, specifically greater than or equal to 30% by weight, particularly greater than or equal to 40% by weight or even greater than or equal to 50% by weight of total olefins comprising 2, 3, and 4 carbon atoms. These C2, C3, and C4 olefins can then be advantageously used as polyolefin monomers.

[0229] According to a preferred embodiment of the present invention, a method for processing feedstock comprising plastic pyrolysis oil and feedstock derived from renewable sources comprises, preferably, the following steps in a sequence, and preferably in the following predetermined order: a) Hydrogenation demetallization, b) Hydrogenation treatment, c) Separation, d) or a) Hydrogenation demetallization, b) Hydrogenation treatment, c) Separation, d) Fractionation, e) or (b) Hydrodemetallization, (c) Hydrotreating, (d) Separation, (e) Fractionation, and recycling of fractions containing compounds with boiling points less than or equal to 175°C back to the hydrotreating step (c). In order to produce effluents, at least a portion of which are compatible with the treatment in the steam cracking unit.

[0230] According to another preferred embodiment of the present invention, a method for processing a feedstock containing cracked oil comprises, preferably, the following steps in a sequence, and preferably in the following predetermined order: Hydrodemetallization (b), hydrotreatment (c), hydrocracking (c'), separation (d) or a) Hydrodemetallization (b) Hydrotreating (c) Hydrocracking (c') Separation (d) Fractionation (e) or (b) Hydrodemetallization; (c) Hydrotreating; (c') Hydrocracking; (d) Complete separation; (e) Fractionation; and recycling of fractions containing compounds with boiling points greater than 175°C to the hydrocracking step (c') and recycling of fractions containing compounds with boiling points less than or equal to 175°C to the hydrotreating step (c). In order to produce effluents, at least a portion of which are compatible with the treatment in the steam cracking unit.

[0231] All embodiments may additionally include and preferably consist of a preprocessing step a0).

[0232] All embodiments may additionally include, and are preferably composed of, a selective hydrogenation step a).

[0233] All embodiments may additionally include, and preferably consist of, a steam cracking step f).

[0234] [Analysis Methods Used] [] Those skilled in this art are familiar with the analytical methods and / or standards used to determine the characteristics of various streams (specifically, the raw materials and effluents to be processed). These are specifically listed below with the aid of information. Other well-known equivalent methods, especially equivalent IP, EN, or ISO methods, may also be used: Table 1 [describe] [method] Density at 15°C ASTM D4052 Sulfur content ISO 20846 Nitrogen content ASTM D4629 acid value ASTM D664 bromine value ASTM D1159 Diene content based on maleic anhydride value MAV Method (1) Molecular content after oxidation Combustion + Infrared Alkane content UOP990-11 cycloalkanes and olefins content UOP990-11 Aromatic content UOP990-11 Halogen content ASTM D7359 Chloride content ASTM D7536 Metal content: ASTM D5185 P Fe Si Na B Simulated distillation ASTM D2887 (1) The MAV method described in the following article: C. López-García 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), 1st ed., pp. 57-68

[0235] [] [List of diagrams] [] The information regarding the elements mentioned in Figures 1 and 2 enables a better understanding of the invention, but the invention is not limited to the specific embodiments illustrated in Figures 1 and 2. The various embodiments presented can be used alone or in combination with each other without any limitation on the combination.

[0236] Figure 1 illustrates a flow chart of a specific embodiment of the method of the present invention, which includes: - Selective hydrogenation step a): Selective hydrogenation of feedstock 1 containing plastic pyrolysis oil in the presence of hydrogen-rich gas 2 and, if appropriate, amine supplied by stream 3, is carried out in at least one fixed-bed reactor including at least one selective hydrogenation catalyst to obtain effluent 4; - Hydrodemetallization step b): Hydrodemetallization of the effluent 4 obtained from step a) in the presence of hydrogen 5 is carried out in at least one fixed-bed reactor containing at least one hydrodemetallization catalyst to obtain demetallized effluent 6; - Hydrotreating step c): Hydrotreating at least a portion of the effluent obtained from step b) in the presence of hydrogen gas 7, which is carried out in at least one fixed-bed reactor containing at least one hydrotreating catalyst to obtain hydrotreating effluent 8; Furthermore, feedstock 20 from a renewable source is introduced into hydrotreating step c) (this feedstock may also be partially or completely introduced into steps a) and / or b) (not shown). - Hydrocracking step c' (optional): At least a portion of the effluent 8 obtained from step c) is hydrocracking in the presence of hydrogen 9, which is carried out in at least one fixed-bed reactor containing at least one hydrocracking catalyst to obtain hydrotreated effluent 10; - Separation step d): Separation effluent 10, which is performed in the presence of an aqueous washing solution 11, makes it possible to obtain at least one fraction 12 containing hydrogen, an aqueous fraction 13 containing dissolved salts, and a hydrocarbon-based liquid fraction 14; - Fractionation step e, as appropriate: Fractionate the hydrocarbon-based liquid fraction 14 to obtain at least one gas fraction 15, a hydrocarbon fraction 16 containing compounds with a boiling point less than or equal to 175°C, and a hydrocarbon fraction 17 containing compounds with a boiling point greater than 175°C.

[0237] At the end of step d) or e), at least a portion of the hydrogenated hydrocarbon-based liquid effluent 16 is fed to a steam cracking process (not shown).

[0238] Depending on the circumstances, a portion of the hydrocarbon fraction 16 containing compounds with a boiling point less than or equal to 175°C constitutes a portion of the recycle streams 16a and / or 16b and / or 16c, respectively fed into steps a) and / or b) and / or c).

[0239] Depending on the circumstances, a portion of fraction 17 containing compounds with a boiling point greater than 175°C is fed into hydrocracking step c' (part 17a), while another portion 17b constitutes a purging step.

[0240] Figure 2 illustrates a flow chart of another specific embodiment of the method of the present invention, based on the flow chart of Figure 1. This flow chart specifically includes a second hydrocracking step (c''), in which fraction 17, containing compounds with boiling points greater than 175°C obtained from step e), is fed into this second hydrocracking step (c'') (part 17a), which is carried out in at least one fixed-bed reactor containing at least one hydrocracking catalyst; and hydrogen 18 is fed into the reactor. The second hydrocracking effluent 19 is recycled to separation step d). Other portions of fraction 17 constitute purging step 17b.

[0241] Instead of injecting amine stream 3 at the inlet of selective hydrogenation step a), it may be injected at the inlets of steps b), c), c') and d), or it may not be injected at all depending on the characteristics of the feedstock.

[0242] Figures 1 and 2 show only the main steps using the primary flow to better understand the invention. It is clearly understood that even without the illustrations, all the necessary equipment for operation (containers, pumps, exchangers, furnaces, tubing, etc.) is present. It should also be understood that the hydrogen-rich gas flow (supply or recirculation) as described above can be injected into the inlet of each reactor or catalyst bed, or between two reactors or two catalyst beds. Methods for purifying and recirculating hydrogen, well-known to those skilled in the art, can also be used.

[0243] [] [Example] [] [Example] [1] [(] [According to the present invention] [)] [] The feedstock 1 processed in this method is plastic pyrolysis oil. The feedstock 2 processed in this method is a feedstock derived from a renewable source (rapeseed oil). The plastic pyrolysis oil is fed into the hydrodemetallization step b). The rapeseed oil is fed into the hydrotreating step c). The characteristics of these feedstocks are indicated in Table 2. Table 2: Raw Material Characteristics [describe] [method] [unit] [raw material] [1] [Plastic pyrolysis oil] [raw material] [2] [Rapeseed oil] Density at 15°C ASTM D4052 g / cm 3 0.7982 0.9201 Sulfur content ISO 20846 ppm weight (ppm poids) 71 4 Nitrogen content ASTM D4629 ppm by weight 871 18.4 bromine content ASTM D1159 g / 100g 50 18.4 Molecular content after oxidation Combustion + Infrared weight% 0.46 11 Chloride content ASTM D7536 ppm by weight 95 0 Metal content ASTM D5185 iron 2 <0.5 P ppm by weight 6.27 10 Si ppm by weight twenty two 0 Simulated distillation ASTM D2887 0% ℃ 60.0 319.5 10% ℃ 133.7 570.7 30% ℃ 199.1 600.9 50% ℃ 270.5 607.0 70% ℃ 334.7 611.7 90% ℃ 403.4 616.0 100% ℃ 574.5 660.6

[0244] The hydrodemetallization step b) of feedstock 1 is carried out in a fixed-bed reactor in the presence of hydrogen 5 and a hydrodemetallization catalyst of the CoMo on alumina type, under the conditions presented in Table 3. Table 3: Conditions for hydrogenation demetallization step b) Hydrodemetallization temperature ℃ 300 hydrogen partial pressure MPa abs 3.1 H₂ / HC (volume coverage of hydrogen relative to the feedstock volume) Nm³ / m³ 300 HSV (feed volumetric flow rate / catalyst volume) h -1 1

[0245] The characteristics of the effluent obtained from the hydrodemetallization step b) (which corresponds to liquid effluent 6) are presented in Table 4: Table 4: Characteristics of the effluent obtained from hydrodemetallization step b). [describe] [method] [unit] [Originated from steps] [b)] [Outflowing material] [(6)] Density at 15°C ASTM D4052 g / cm 3 0.7921 Sulfur content ASTM D5453 ppm by weight 37.8 Nitrogen content ASTM D4629 ppm by weight 586.3 bromine content ASTM D1159 g / 100 g 20.13 Molecular content after oxidation Combustion + Infrared weight% 0 Chloride content ASTM D7536 ppm by weight 4.7 Metal content: ASTM D5185 iron ppm by weight 1.4 P ppm by weight 1.4 Si ppm by weight < 1

[0246] The effluent 6 obtained from the hydrodemetallization step b) is subjected to a hydrotreating step c) according to the present invention. Feed 2 from renewable source 20 is also introduced into the hydrotreating step c). The feedstock in the hydrotreating step c) is a mixture of 50% by weight of the hydrodemetallization effluent obtained from plastic pyrolysis oil and 50% by weight of rapeseed oil.

[0247] The hydrotreating step c) is performed in a fixed-bed reactor under the conditions presented in Table 5, in the presence of hydrogen 7 and a hydrotreating catalyst of the NiMo on alumina type. Table 5: Conditions for hydrotreating step c) Hydrogenation processing temperature ℃ 310 hydrogen partial pressure MPa abs 5.1 H₂ / HC (volume coverage of hydrogen relative to the feedstock volume) Nm³ / m³ 700 HSV (feed volumetric flow rate / catalyst volume) h -1 0.5

[0248] The effluent 8 obtained from hydrotreating step c) is subjected to a separation step d) according to the invention, wherein a water stream 11 is injected into the effluent obtained from hydrotreating step c); the mixture is then conveyed to separation step d) and treated in a column for washing acidic gases. A gas fraction is obtained at the top of the acidic gas washing column, while at the bottom, a two-phase separation vessel separates the aqueous and liquid phases. The gas washing column and two-phase separator operate under high pressure. The liquid phase is then conveyed to a low-pressure vessel for recovery of the purged second gas fraction and the liquid effluent. The yields of the various products and fractions obtained at the outlet of hydrotreating step c) are indicated in Table 6 (yields correspond to the weight ratio of the various products obtained to the weight of the feedstock, expressed as a percentage and labeled % w / w). Table 6: Yields of various products and fractions obtained at the outlet of hydrotreating step c) H₂S - NH₃ % m / m 0.1 CO % m / m 0.1 CO2 % m / m 0.6 H₂O [%] % m / m 4.0 C1-C4 % m / m 2.7 PI -180℃ fraction % m / m 11.8 180℃+ grade % m / m 82.8 total % m / m 102.0

[0249] The characteristics of the effluent obtained from separation step d) (which corresponds to liquid effluent 14) are presented in Table 7: Table 7: Characteristics of effluent 14 obtained from separation step d) [describe] [method] [unit] [Effluent(14)] Density at 15°C ASTM D4052 g / cm3 0.7908 Sulfur content ASTM D5453 ppm by weight 4.5 Nitrogen content ASTM D4629 ppm by weight 2.2 bromine content ASTM D1159 g / 100 g <0.8 Molecular content after oxidation Combustion + Infrared weight% <0.1 Chloride content ASTM D7536 ppm by weight Not detected Iron content ASTM D5185 ppb by weight Not detected Total metal content ppm by weight Not detected

[0250] The hydrocarbon-based effluent 14 obtained from separation step d) has a composition compatible with the steam cracking unit because: - It contains no olefins (monoolefins and dienes); - It contains no chlorine (no chlorine was detected and the content is below the limit required for steam cracking feedstock); - It contains no iron (Fe) or any other metals (no metal content was detected and the content was below the limits required for steam cracking feedstock, i.e., ≤ 5.0 ppm by weight for metals and preferably ≤ 1 ppm by weight; and ≤ 100 ppb by weight for Fe). Finally, it contains very little sulfur (<5.5 ppm by weight) and very little nitrogen (<1.8 ppm by weight), which are far below the limits required for steam cracking feedstock (≤ 500 ppm by weight for S and N, preferably ≤ 200 ppm by weight). []

[0251] The effluent 14 obtained from separation step d) consists of approximately 11.8% naphtha-type compounds with a boiling point less than or equal to 180°C.

[0252] Effluent 14 can be directly transported to steam cracking step f).

[0253] 1: Raw materials containing plastic pyrolysis oil 2: Hydrogen-rich gas 3: Amine flow 4: Effluent 5: Hydrogen 6: Drained metal effluent 7: Hydrogen 8: Effluent from hydrotreating 9: Hydrogen 10: Effluent from hydrotreating 11: Aqueous washing solution 12: Contains hydrogen fractions 13: Aqueous fraction containing dissolved salts 14: Liquid fractionation based on hydrocarbons 15: Gas stages 16: Hydrocarbon fractions containing compounds with a boiling point of 175°C or less. 16a: Recirculation Flow 16b: Recirculating Flow 16c: Recirculating Flow 17: Hydrocarbon fractions containing compounds with boiling points greater than 175°C 17a: Part 17b: Part 18: Hydrogen 19: Second hydrocracking effluent 20: Raw materials derived from renewable sources a): Selective hydrogenation step to be used as appropriate. b): Hydrodemetallization step c): Hydrogenation treatment steps c'): Hydrocracking steps to be selected as appropriate. c''): Second hydrocracking step d): Separation steps e): Fractionation steps

Claims

1. A method for processing feedstock comprising plastic pyrolysis oil and feedstock derived from a renewable source, comprising: a) a selective hydrogenation step, performed, as appropriate, in the presence of at least one selective hydrogenation catalyst, at a temperature between 80 and 280°C, a hydrogen partial pressure between 1.0 and 20.0 MPa abs., and an hourly space velocity between 0.3 and 10.0 h⁻¹, in a reaction section fed with at least the feedstock comprising plastic pyrolysis oil and a hydrogen-containing gas stream, to obtain a hydrogenated effluent; b) a hydrodemetallization step, performed in a hydrodemetallization reaction section comprising at least one hydrodemetallization catalyst, the hydrodemetallization reaction section being fed with at least the feedstock comprising plastic pyrolysis oil and / or the hydrogenated effluent from step a) and a hydrogen-containing gas stream, the hydrodemetallization reaction section being at an average temperature between 140 and 400°C, and at an hourly space velocity between 1.0 and 20.0 MPa abs. The process is carried out at a hydrogen partial pressure between abs. and a space velocity between 0.1 and 10.0 h⁻¹ to obtain a demetallized effluent; c) a hydrotreating step, which is carried out in a hydrotreating reaction section containing at least one hydrotreating catalyst, the hydrotreating reaction section being fed at least the demetallized effluent obtained from step b) and a hydrogen-containing gas stream, the hydrotreating reaction section being used at a temperature between 250 and 450°C, a hydrogen partial pressure between 1.0 and 10.0 MPa abs. and a space velocity between 0.1 and 10.0 h⁻¹, and wherein the feedstock from a renewable source is introduced into steps a) and / or steps b) and / or steps c) as a mixture with the feedstock containing plastic pyrolysis oil, the weight ratio between the flow rate of the feedstock containing the plastic pyrolysis oil and the flow rate of the feedstock from a renewable source being introduced is between 0.05 and 20; c') The selected hydrocracking step, as appropriate, is carried out in a hydrocracking reaction section containing at least one hydrocracking catalyst. This hydrocracking reaction section is fed at least the hydrotreated effluent from step c) and / or the fraction containing compounds with boiling points greater than 175°C from step e) and a hydrogen-containing gas stream. The hydrocracking reaction section is maintained at an average temperature between 250 and 450°C, a hydrogen partial pressure between 1.5 and 20.0 MPa abs., and a hydrogen partial pressure between 0.1 and 10 MPa abs.The process is used at a space velocity between 0 h⁻¹ to obtain the hydrocracked effluent delivered to separation step d). Step d) is a separation step, fed by the hydrotreated effluent from step c) and / or the hydrocracked effluent from step c') and an aqueous solution. This step is performed at a temperature between 50 and 450°C to obtain at least one gaseous effluent, an aqueous effluent, and a hydrocarbon-based effluent. Step e), as appropriate, involves fractionation of all or part of the hydrocarbon-based effluent from step d) to obtain at least one gaseous effluent and at least one fraction containing a compound with a boiling point less than or equal to 175°C and a hydrocarbon fraction containing a compound with a boiling point greater than 175°C.

2. The method of claim 1, which includes the fractionation step e).

3. The method as requested in claim 1 or 2, which includes the hydrocracking step c').

4. The method as claimed in claim 1 or 2, which includes the selective hydrogenation step a).

5. The method of claim 1 or 2, wherein the raw material derived from a renewable source is a raw material comprising oils and / or fats of plant and / or animal origin.

6. The method of claim 1 or 2, wherein at least a portion of the raw material derived from a renewable source is introduced in step c).

7. The method of claim 1 or 2, wherein the temperature of the reaction zone in step c) is higher than the temperature of the hydrogenation demetallization reaction zone in step b).

8. The method of claim 1 or 2, wherein at least a portion of the hydrocarbon-based effluent obtained from the separation step d) or at least a portion of the fraction containing compounds with a boiling point less than or equal to 175°C obtained from the fractionation step e) is fed as a recycle stream to the selective hydrogenation step a) and / or the hydrodemetallization step b) and / or the hydrotreatment step c).

9. The method of claim 1 or 2, wherein at least a portion of the fraction containing a compound with a boiling point greater than 175°C obtained from the fractionation step e) is fed as a recycle stream to the hydrodemetallization step b) and / or the hydrotreatment step c) and / or the hydrocracking step c').

10. The method of claim 8, wherein the weight ratio between the recycled stream and the feedstock comprising plastic pyrolysis oil and feedstock from a renewable source is less than or equal to 10.

11. The method of claim 1 or 2, comprising a step a0) of pretreating the raw material, the pretreating step being performed upstream of the selective hydrogenation step a) and comprising a filtration step and / or an electrostatic separation step and / or a washing step by means of an aqueous solution and / or an adsorption step.

12. The method of claim 1 or 2, wherein at least one of the hydrocarbon-based effluent obtained from the separation step d) or the two hydrocarbon-based liquid streams obtained from step e) is wholly or partially transported to a steam cracking step f) performed in at least one pyrolysis furnace at a temperature between 700 and 900°C and a pressure between 0.05 and 0.3 MPa.

13. The method of claim 1 or 2, wherein the selective hydrogenation catalyst comprises a support and a hydrodehydrogenation function, the support being selected from alumina, silicon dioxide, silicon dioxide-alumina, magnesium oxide, clay and mixtures thereof, and the hydrodehydrogenation function comprising at least one group VIII element and at least one group VIB element, or at least one group VIII element.

14. The method of claim 1 or 2, wherein the hydrodemetallization catalyst and the hydrotreatment catalyst comprise a support and hydrodehydrogenation functionality, the support being selected from the group consisting of alumina, silicon dioxide, silicon dioxide-alumina, magnesium oxide, clay and mixtures thereof, and the hydrodehydrogenation functionality comprising at least one group VIII element and / or at least one group VIB element.

15. The method of claim 1 or 2, further comprising a second hydrocracking step c'') performed in a hydrocracking reaction section containing at least one hydrocracking catalyst, the hydrocracking reaction section being fed with the fraction containing compounds with boiling points greater than 175°C obtained from step e) and a gas stream containing hydrogen, the hydrocracking reaction section being used at a temperature between 250 and 450°C, a hydrogen partial pressure between 1.5 and 20.0 MPa abs., and a space velocity between 0.1 and 10.0 h⁻¹, to obtain the hydrocracking effluent to be conveyed to the separation step d).

16. The method of claim 1 or 2, wherein the hydrocracking catalyst comprises a support and hydrodehydrogenation functionality, the support being selected from a combination of alumina halides, boron and aluminum oxides, amorphous silica-alumina, and zeolite, and the hydrodehydrogenation functionality comprising at least one group VIB metal selected from chromium, molybdenum, and tungsten alone or in mixtures, and / or at least one group VIII metal selected from iron, cobalt, nickel, ruthenium, rhodium, palladium, and platinum.

17. The method of claim 1 or 2, wherein the raw material has the following characteristics: the content of aromatic compounds is between 0 and 90% by weight, the content of halogenated compounds is between 2 and 5000 ppm by weight, the content of metal elements is between 10 and 10000 ppm by weight, including the content of iron elements is between 0 and 100 ppm by weight, and the content of silicon elements is between 0 and 1000 ppm by weight.

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