Method for hydrotreating and hydroisomerizing vegetable oil in one step using at least one hydrotreating catalyst based on group VIB and viii metals

Abstract

The present invention describes a method for treating a feedstock obtained from a renewable source implementing a sequence of at least one hydrotreating step using a specific hydrodeoxygenation catalyst comprising at least one metal from group VIII, in combination with at least one metal from group VIB of the periodic table, the molar ratio between the group VIII and group VIB elements being between 0.02 and 0.2, at least one organic additive and an oxide support comprising at least alumina, followed by a hydroisomerization step in a single step, in order to produce at least one gas oil fraction.

Description

[0001] One-step hydrotreating and hydroisomerizing process for vegetable oil using at least one hydrotreating catalyst based on metals from groups VIB and VIII.

[0002] Scope of the invention

[0003] The search for new renewable energy sources for fuel production is a major challenge to both meet fuel demand and address environmental concerns and the decarbonization of the road and air transport sector.

[0004] As such, the use of feedstocks from renewable sources in fuel production has seen a significant resurgence of interest in recent years. Examples of these feedstocks include vegetable oils such as rapeseed or soybean oil, animal fats, used cooking oils, and mixtures of such feedstocks. These feedstocks contain chemical structures such as triglycerides, esters, or fatty acids. Fat chains consist of a hydrocarbon structure with varying chain lengths and generally comprise 16 to 18 carbon atoms. Other types of feedstocks containing fatty acids include tall oil from the paper industry and fats derived from cover crops such as camelina and carinata oils.

[0005] One possible approach is the catalytic transformation of these feedstocks from renewable sources by hydrotreating (in the presence of hydrogen) into deoxygenated paraffinic fuel. Numerous metallic or sulfide catalysts are known to be active in this type of reaction. Depending on the length of the hydrocarbon chains, the resulting linear paraffins have boiling points compatible with the hydrocarbons present in fossil diesel and kerosene base fuels.

[0006] These hydrotreating processes for feedstock from renewable sources are already well known and are described in numerous patents. Examples include patents: US 4,992,605, US 5,705,722, EP 1,681,337 and EP 1,741,768.

[0007] Transition metal sulfide-based catalysts enable the production of linear paraffins by transforming oxygenated compounds via two reaction pathways:

[0008] - Hydrodeoxygenation (HDO) leading to the formation of water by hydrogen consumption and the formation of hydrocarbons of carbon number (C n ) equal to that of the initial fatty acid chains,

[0009] - Decarboxylation / decarbonylation (DCO) leading to the formation of carbon oxides (carbon monoxide and carbon dioxide: CO and CO2) and the formation of hydrocarbons with one less carbon atom (C n -i) compared to the initial fatty acid chains. This transformation also leads to the formation of by-products such as propane (from the glyceric structure of fats) and methane (by methanation reaction of carbon oxides under hydrotreating conditions).

[0010] The liquid effluent from these hydrotreating processes, after gas separation, consists primarily of n-paraffins and is substantially free of sulfur, nitrogen, and oxygen impurities. This effluent typically has a sulfur content between 1 and 20 ppm wt., a nitrogen content generally between 0.2 and 30 ppm wt., and an oxygen content generally below 2000 ppm wt. The paraffins typically have a carbon atom count between 9 and 25, which is mainly dependent on the fatty acid chain distribution of the renewable feedstock being hydrotreated.

[0011] However, this liquid effluent cannot generally be directly incorporated into the kerosene or diesel pool because it does not meet all fuel specifications, for example, due to insufficient cold-weather properties and / or excessively high boiling points. Indeed, the linear paraffins present lead to high pour points and therefore to freezing phenomena at low temperatures. For example, eicosane (a linear paraffin with 20 carbon atoms, C20H42) has a boiling point of 340°C and a melting point of 37°C. While eicosane's boiling point is compatible with its incorporation into a diesel pool, its melting point can cause freezing problems and limit its use. As an illustration, the maximum filter plugging point for winter diesel is -15°C according to French regulations (EN590 standard).Furthermore, the boiling point of eicosane makes it unsuitable for incorporation into the kerosene pool, for which the final temperature of the D86 distillation curve must be less than 300°C (ASTM D1655 standard).

[0012] Depending on the type of fuel being produced (kerosene or diesel) and the required fuel specifications, an additional hydroconversion step (hydroisomerization and / or hydrocracking reactions) may be necessary to transform the linear paraffins in the hydrotreated liquid effluent. Hydroisomerization converts a linear paraffin into a branched paraffin while preserving the number of carbon atoms in the molecule. This improves the cold-weather properties of the effluent because branched paraffins exhibit better cold-weather properties and a lower boiling point than corresponding linear paraffins with the same number of carbon atoms. For example, nonadecane has a melting point of 32°C, while one of its monobranch isomers, 7-methyloctadecane, has a melting point of -16°C. Hydrocracking allows the conversion of linear paraffin into linear or branched paraffins of smaller molecular weights.This allows the effluent distillation curve to be adjusted as needed to make it compatible with the kerosene pool, which has more stringent cold-weather property and maximum boiling point specifications. For example, hydrocracking one molecule of eicosane can lead to the production of two molecules of 2-methylnonane. The boiling point of 2-methylnonane is 167°C, which is compatible with its inclusion in the kerosene pool in terms of boiling point. The hydroconversion step is carried out on a bifunctional catalyst exhibiting both a hydro / dehydrogenating function and a Brønsted acid function. The operating conditions can be adapted to favor either hydroisomerization or hydrocracking reactions, depending on the requirements. In all cases, it is desirable to minimize the production of excessively light cracking products that cannot be incorporated into the kerosene and diesel fractions, in order to maximize their yield.

[0013] The appropriate choice of acidic phase promotes the isomerization of long linear paraffins and minimizes cracking. The shape selectivity of medium-pore (10 MR) or large-pore (12 MR) zeolites makes them particularly suitable for obtaining catalysts selective for isomerization and hydroconversion. Other acidic phases, such as halogenated aluminas (especially chlorinated or fluorinated), phosphorus aluminas, silica-aluminas, or silicified aluminas, can also be used.

[0014] However, it is well known that factors other than the acid phase have an impact on the activity and selectivity of a bifunctional catalyst. Hydroisomerization and hydrocracking of normal paraffins have thus been the subject of numerous academic studies since the original work of Weisz (Weisz P, Adv catal 1962, 13, 137) or Coonradt and Garwood (HL Coonradt, WE Garwood Ind. Eng. Chem. Process Des. Dev., 3 (1) (1964), pp. 38-45).

[0015] The most commonly accepted mechanism involves first dehydrogenating n-paraffin to n-olefin at a hydro-dehydrogenating site and then, after diffusion to a Brønsted acid site, protonating it to a carbenium ion. Following structural rearrangement and / or P-scission, the carbenium ions desorb from the acid phase as olefins after deprotonation. Then, after diffusion to a hydro-dehydrogenating site, the olefins are hydrogenated to form the final reaction products. It is therefore necessary to have a hydro / dehydrogenating group that is sufficiently active with respect to the acid group in order to both rapidly supply the acid phase with olefins and rapidly hydrogenate the olefinic intermediates after their reaction with the acid phase. This allows, on the one hand, the activity of the catalyst to be maximized and, on the other hand, the production of isomerized paraffins to be maximized by limiting overcracking towards light hydrocarbons.The use of a sufficiently active hydrogenating function is also desirable in order to limit the deactivation of the bifunctional catalyst by coking during the hydroconversion of n-paraffins (Alvarez et al., Journal of Catalysis, 162, 2, 179-189) for a range of fixed operating conditions.

[0016] Noble metals (Pt, Pd) or transition metals from group VIB (Mo, W) combined with transition metals from group VIII (Ni, Co) can act as hydro- / dehydrogenating agents for the catalyst. Noble metals are used in their reduced form, while transition metals from groups VIB and VIII are used in their sulfide form.

[0017] The choice of the type of hydro / dehydrogenating agent, whether a noble metal or a transition metal sulfide, depends on various criteria, including economic factors (noble metals are significantly more expensive than transition metals from groups VI B and VIII) and the nature of the feedstock to be converted (impact of contaminants). Thus, the hydro / dehydrogenating activity of noble metals is higher than that of transition metal sulfides when the partial pressure of hydrogen sulfide (H₂S) in the reaction medium is low or even zero.

[0018] US patent 8809610 (SHELL) claims a process for the production of paraffinic hydrocarbons from a feed containing triglycerides, diglycerides, monoglycerides, and / or fatty acids. The process comprises (a) a hydrodeoxygenation step in the presence of hydrogen and a catalyst to obtain an effluent comprising water and paraffins, (b) a separation step of the effluent from (a) to obtain a liquid effluent rich in paraffins, and (c) a hydroisomerization step of said paraffin-rich effluent in the presence of hydrogen and a catalyst comprising nickel sulfide and tungsten sulfide and / or molybdenum sulfide as hydrogenating phases and a support comprising silica-alumina and / or a zeolite. It is taught that the use of sulfide phases instead of noble metals as hydrogenating phases makes it possible not to have to completely remove impurities from the effluent from step (a).

[0019] US patent 8039682 describes a process for producing kerosene from a renewable feedstock, comprising a hydrotreating, isomerization, and selective hydrocracking step in the presence of a multifunctional catalyst or a series of catalysts, a gas / liquid separation step of the resulting effluent followed by a fractionation step to produce a jet effluent, naphtha, and a residual effluent heavier than the jet, and then recycling this residual effluent into the reaction zone with a recycle ratio relative to the fresh feedstock of between 0.1 and 8. The deoxygenation and hydrogenation function of the catalyst or series of catalysts that can be used in the process according to the invention can be ensured by a noble metal such as platinum, palladium, rhodium, and ruthenium, or by sulfide metals such as a sulfide-coated NiMo or sulfide-coated NiW active phase.The acid function required for isomerization and / or selective hydrocracking reactions can be provided by a zeolite such as, for example, 10MR and 12MR zeolites, structural zeolites BEA, MOR, MFI, or FAU, or by amorphous alumina silica. The patent cites numerous examples of catalysts that can be used in the process according to the invention: a Pt-based catalyst dispersed on a support comprising a Y zeolite (FAU), a catalyst comprising Pt and Pd on a support comprising a Y zeolite and amorphous alumina silica. In another embodiment, a catalyst comprising Pt and / or Pd on a Y zeolite, ZSM-5 (MFI), amorphous alumina silica, MOR, SAPO-11, and / or SM3 can be used to catalyze all types of reactions. In another embodiment, a catalyst comprising a sulfide NiMo phase on a zeolite Y, ZSM-5, an amorphous alumina silica, MOR, SAPO-11 and / or SM3 can also be used.A catalyst series can also consist of a sequence of NiMo sulfide supported on amorphous alumina silica followed by a Pt-based catalyst supported on amorphous alumina silica. Numerous other catalysts for deoxygenation, isomerization, and selective hydrocracking are also mentioned. For example, a long list of hydrocracking / isomerization catalysts is cited and includes a Group VIII metal such as Pt and / or Pd, and a support which may be amorphous or crystalline, said support being able to include aluminas, amorphous alumina silica, and ferrierite-type zeolites, ALPO-31, SAPO-11, SAPO-31, SAPO-37, SAPO-41, SM-3, MgAPSO-31, FU-9, NU-10, NU-23, ZSM-12, ZSM-22, ZSM-23, ZSM-35, ZSM-48, ZSM-50, ZSM-57, MeAPO-11, MeAPO-31, MeAPO-41, MeAPSO-11, MeAPSO-31, MeAPSO-41, MeAPSO-46, ELAPO-II, ELAPO-31, ELAPO-41, ELAPSO-I I, ELAPSO-31, ELAPSO-41.This patent also demonstrates that it is possible to carry out the hydroisomerization and hydrocracking steps without prior removal of the water and carbon oxides generated during the hydrotreatment step. The patent example does indeed describe the sequence of two catalysts without specifying their nature or the presence of zeolite.

[0020] In attempting to develop a process for treating feedstocks from renewable sources to produce middle distillates, the applicant surprisingly demonstrated that a sequence of at least one hydrotreating step of said feedstock using a specific hydrodeoxygenation catalyst comprising at least one metal from Group VIII, in combination with at least one metal from Group VIB of the periodic table, the molar ratio between the elements of Group VIII and Group VIB being between 0.02 and 0.2, at least one organic additive and an oxide support comprising at least alumina followed by a single-step hydroisomerization step (i.e. without any intermediate separation of the effluent from the hydrotreating step) made it possible to obtain improved activity of said hydroisomerization catalyst downstream, while increasing yields of middle distillates and preferably of diesel cut,compared to the implementation of catalysts conventionally used in the prior art in a one-step process.

[0021] The intrinsic selectivity of the hydrotreating catalyst and the attainment of high catalytic activity of the hydroisomerization catalyst thus make it possible, for example, to increase the lifetime of the hydroisomerization catalyst and to limit the frequency of replacement of fresh hydrotreating and hydroisomerization catalysts in a single-step process.

[0022] Another advantage of the present invention is that it provides a single-stage process comprising a single effluent fractionation zone from the hydroisomerization stage. This process is more economical than a two-stage process and allows the use of existing hydrotreating units with limited investment, while also enabling high yields of middle distillate fractions and, preferably, renewable diesel fractions. The intrinsic selectivity of the hydrotreating catalyst is particularly advantageous as it limits the accumulation of carbon oxides and methane in the single-stage process with a closed-loop hydrogen recycling circuit, and mitigates the gradual decrease in hydrogen partial pressure in the reactor associated with the concomitant increase in carbon oxide and methane partial pressures in such a process.

[0023] Another advantage of the present invention is to maximize the biogenic carbon yield of the process operating in a single step.

[0024] In the sense of the present invention, the different embodiments presented can be used alone or in combination with each other, without limitation of combination.

[0025] In the sense of the present invention, the different ranges of operating parameters for a given step, such as pressure ranges and temperature ranges, can be used alone or in combination. For example, in the sense of the present invention, a preferred range of pressure values ​​can be combined with a more preferred range of temperature values.

[0026] In the following text, chemical element groups are given according to the CAS classification (CRC Handbook of Chemistry and Physics, publisher CRC Press, editor-in-chief DR Lide, 81st edition, 2000-2001). For example, group VIII according to the CAS classification corresponds to the metals in columns 8, 9, and 10 according to the new IUPAC classification, and group VIB to the metals in column 6.

[0027] In the following text, the expressions "between ... and ..." and "between ... and ..." are equivalent and mean that the limit values ​​of the interval are included within the described range of values. If this were not the case and the limit values ​​were not included within the described range, this clarification will be provided by the present invention.

[0028] In this description, the expression "greater than..." is understood as strictly greater, and symbolized by the sign ">", and the expression "less than" as strictly less, and symbolized by the sign "<".

[0029] Object of the invention

[0030] More specifically, the present invention relates to a process for treating a feedstock from a renewable source comprising at least the following steps, and preferably consisting of the following steps: a) a hydrotreating step of said feedstock in the presence of at least one fixed-bed catalyst, said hydrodeoxygenation catalyst comprising at least one metal from Group VIII, in combination with at least one metal from Group VIB of the periodic table, the molar ratio between the elements of Group VIII and Group VIB being between 0.02 and 0.2, at least one organic additive, and a support comprising at least one oxide, at a temperature between 200 and 450°C, at a pressure between 1 MPa and 10 MPa, at a space-hour velocity between 0.1 h -1 and 10 a.m. -1 and in the presence of a total quantity of hydrogen mixed with the charge such that the hydrogen / charge ratio is between 70 and 1700 Nm 3 hydrogen / m3 of charge, b) a hydroisomerization step of all the hydrocarbon liquid effluent from step a) in the presence of a fixed-bed bifunctional hydroisomerization catalyst, said catalyst comprising a sulfide phase of at least one metal from Group VIII in combination with at least one metal from Group VIB of the periodic table and a support comprising at least one zeolite and / or silica-alumina, said hydroisomerization step being carried out at a temperature between 250°C and 500°C, at a pressure between 1 MPa and 10 MPa, at a spatial rate between 0.1 and 10 h -1 and in the presence of a total quantity of hydrogen mixed with the charge such that the hydrogen / charge ratio is between 70 and 1500 Nm 3 / m 3 of charge, c) a step of fractionating the effluent from step b) to obtain at least a diesel fraction.

[0031] Preferably, the hydrotreating step a) and hydroisomerization step b) are carried out in a single step, the process according to the invention not comprising an intermediate separation step, preferably for separating gases and liquids, between step a) and step b).

[0032] An advantage of the present invention is to provide a one-stage process comprising a single effluent fractionation zone from the hydroisomerization stage, which is more economical than a two-stage process and allows the use of existing hydrotreatment units with limited investment, while enabling high yields in middle distillate cuts and preferably in renewable diesel cuts.

[0033] Another advantage of the present invention is that it provides a process for treating feedstocks from renewable sources, employing a sequence of at least one hydrotreating step of said feedstock using a specific hydrodeoxygenation catalyst comprising at least one metal from Group VIII, in combination with at least one metal from Group VIB of the periodic table, the molar ratio between the Group VIII and Group VIB elements being between 0.02 and 0.2, at least one organic additive, and an oxide support comprising at least alumina, followed by a single-step hydroisomerization step. This process allows for improved downstream activity of said hydroisomerization catalyst, while increasing yields of middle distillates and preferably diesel fuel, compared to the use of catalysts conventionally employed in the prior art in a single-step process. Detailed description of the invention

[0034] Charges

[0035] The present invention is particularly dedicated to the preparation of diesel fuel bases and possibly kerosene fuel bases corresponding to the new environmental standards, from feedstocks from renewable sources.

[0036] The feedstocks from renewable sources used in the process according to the present invention are advantageously selected from oils and fats of vegetable or animal origin, or mixtures of such feedstocks, containing triglycerides and / or free fatty acids and / or esters. The vegetable oils may advantageously be crude or refined, wholly or partially, and derived from the following plants: rapeseed, sunflower, soybean, palm, palm kernel, olive, coconut, jatropha, this list not being exhaustive. Algae or fish oils are also suitable. The animal fats are advantageously selected from lard or fats composed of residues from the food industry or from the catering industry.

[0037] These fillers primarily contain triglyceride-type chemical structures, also known to those skilled in the art as fatty acid triesters, as well as free fatty acids. A fatty acid triester is thus composed of three fatty acid chains. These fatty acid chains, whether in triester or free fatty acid form, have a number of unsaturations per chain, also called the number of carbon-carbon double bonds per chain, generally between 0 and 3, but which can be higher, particularly for oils derived from algae, which typically have 5 to 6 unsaturations per chain.

[0038] The molecules present in the feeds from renewable sources used in the present invention therefore have a number of unsaturations, expressed per triglyceride molecule, advantageously between 0 and 18. In these feeds, the degree of unsaturation, expressed as the number of unsaturations per hydrocarbon fatty chain, is advantageously between 0 and 6.

[0039] Feedstocks from renewable sources generally also contain various impurities, including heteroatoms such as nitrogen. Nitrogen levels in vegetable oils, used cooking oils, and animal fats are typically between 1 ppm and approximately 300 ppm by weight, depending on their nature.

[0040] Other types of fillers containing fatty acids can also be mentioned, such as Tall Oil fillers from the paper industry.

[0041] Process and catalysts. Advantageously, the feedstock may undergo a pretreatment or pre-refining step prior to step a) of the process according to the invention in order to remove, by appropriate treatment, contaminants such as metals, alkali compounds (for example, on ion-exchange resins), alkaline earth metals, and phosphorus. Appropriate treatments may, for example, be thermal and / or chemical treatments well known to those skilled in the art.

[0042] According to step a) of the process according to the invention, the feed, optionally pretreated, is brought into contact with at least one fixed-bed hydrotreating catalyst at a temperature between 200 and 450°C, preferably between 220 and 350°C, most preferably between 220 and 320°C, and even more preferably between 220 and 310°C. The pressure is between 1 MPa and 10 MPa, most preferably between 1 MPa and 6 MPa, and even more preferably between 1 MPa and 4 MPa. The hourly spatial velocity, i.e., the feed volume per catalyst volume per hour, is between 0.1 h -1 and 10 a.m. 1 The feedstock is brought into contact with the catalyst in the presence of hydrogen. The total amount of hydrogen mixed with the feedstock is such that the hydrogen / feedstock ratio is between 70 and 1700 Nm 3 hydrogen / m 3 load and preferably between 150 and 1500 Nm 3 hydrogen / m 3 dump.

[0043] In step a) of the process according to the invention, the hydrodeoxygenation catalyst comprises at least one metal from group VIII, in combination with at least one metal from group VIB of the periodic table, the molar ratio between the elements of group VIII and group VIB being between 0.02 and 0.2, at least one organic additive and a support comprising at least one oxide.

[0044] Preferably, the oxide support comprises at least one oxide selected from titanium oxide, alumina, silica, and zirconia, alone or in mixtures. Preferably, said oxide support comprises at least alumina, and preferably, said support is made of alumina, and preferably comprises and is preferably made of alumina r|, 0 OR y, and preferably made of alumina r], 5 or y.

[0045] Said hydrotreating catalyst is advantageously a catalyst comprising at least one metal from group VIII preferably selected from nickel and cobalt, in combination with at least one metal from group VIB preferably selected from molybdenum and tungsten, taken alone or in mixture.

[0046] The content of Group VIII metal oxides, and preferably nickel oxide, is advantageously between 0.1 and 10% by weight, and preferably between 0.5 and 10% by weight of nickel oxide (NiO), and preferably between 0.7 and 5% by weight of nickel oxide. The content of Group VIB metal oxides, and preferably molybdenum trioxide, is advantageously between 5 and 35% by weight of molybdenum oxide (MoOa), preferably from 5 to 30% by weight, the percentages being expressed as % by weight relative to the total mass of the catalyst. The total content of Group VIB and VIII metal oxides in the catalyst used in step a) is advantageously between 5 and 45% by weight, and preferably between 6 and 35% by weight relative to the total mass of the catalyst.

[0047] According to the invention, said catalyst comprises at least one organic additive. Preferably, said catalyst comprises at least one organic additive selected from organic compounds containing oxygen, organic compounds containing nitrogen, organic compounds containing oxygen and nitrogen, and organic compounds containing sulfur, alone or in mixture.

[0048] An oxygen-containing organic compound can be one or more compounds with one or more chemical functionalities, including carboxyl groups, alcohols, ethers, aldehydes, ketones, esters, or carbonates, or compounds containing a furanic ring, or sugars. An oxygen-containing organic compound is defined here as a compound containing no other heteroatoms. As an example, the oxygen-containing organic compound may be one or more chosen from the group consisting of ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol (with a molecular weight between 200 and 1500 g / mol), propylene glycol, 2-butoxyethanol, 2-(2-butoxyethoxy)ethanol, 2-(2-methoxyethoxy)ethanol, triethylene glycol dimethyl ether, glycerol, acetophenone, 2,4-pentanedione, pentanone, acetic acid, oxalic acid, maleic acid, malic acid, malonic acid, oxalic acid,gluconic acid, tartaric acid, citric acid, γ-ketovaleric acid, a C1-C4 dialkyl succinate and more particularly dimethyl succinate, methyl acetoacetate, ethyl acetoacetate, 2-methoxyethyl 3-oxobutanoate, 2-methacryloyloxyethyl 3-oxobutanoate, dibenzofuran, a crown ether, orthophthalic acid, glucose, fructose, sucrose, sorbitol, xylitol, γ-valerolactone, 2-acetylbutyrolactone, propylene carbonate, 2-furaldehyde (also known as furfural), 5-hydroxymethylfurfural (also known as 5-(hydroxymethyl)-2-furaldehyde or 5-HMF), 2-acetylfuran, the 5-methyl-2-furaldehyde, the,

[0049] 2-methyl furoate, furfuryl alcohol (also known as furfuranol), furfuryl acetate, ascorbic acid, butyl lactate, ethyl lactate, butyl butyryllactate, the

[0050] ethyl 3-hydroxybutanoate, ethyl 3-ethoxypropanoate, methyl 3-methoxypropanoate, 2-ethoxyethyl acetate, 2-butoxyethyl acetate, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,5-hexanediol, 3-ethyl-1,5-pentanediol, 2,4-diethyl-1,5-pentanediol, 5-methyl-2(3H)-furanone, butyl glycolate, ethyl 4-oxo-pentanoate, diethyl maleate, dimethyl maleate, dimethyl fumarate, diethyl fumarate, adipate dimethyl, dimethyl 3-oxoglutarate, dimethyl tartrate, diethyl tartrate, diisopropyl tartrate, di-tert-butyl tartrate, dimethyl malate, diethyl malate, diisopropyl malate, and dibutyl malate. Preferably, the organic compound contains oxygen; preferably, it is selected from γ-valerolactone, 2-acetylbutyrolactone, triethylene glycol, and diethylene glycol.ethylene glycol, ethylenediaminetetraacetic acid (EDTA), maleic acid, malonic acid, citric acid, acetic acid, oxalic acid, gluconic acid, glucose, fructose, sucrose, sorbitol, xylitol, γ-ketovaleric acid, a C1-C4 dialkyl succinate and more particularly dimethyl succinate, dimethylformamide, 1-methyl-2-pyrrolidinone, propylene carbonate, 2-methoxyethyl 3-oxobutanoate, bicine, tricine, 2-furaldehyde (also known as furfural), 5-hydroxymethylfurfural (also known as 5-(hydroxymethyl)-2-furaldehyde or 5-HMF), 2-acetylfuran, 5-methyl-2-furaldehyde, ascorbic acid, butyl lactate, ethyl lactate, butyl butyryllactate, ethyl 3-hydroxybutanoate, ethyl 3-ethoxypropanoate, 2-ethoxyethyl acetate, 2-butoxyethyl acetate, 2-hydroxyethyl acrylate, 1-vinyl-2-pyrrolidinone, 1,3-dimethyl-2-imidazolidinone, 1,5-pentanediol, 1-(2-hydroxyethyl)-2-pyrrolidinone, 1-(2-hydroxyethyl)-2,5-pyrrolidinedione, 5-methyl-2(3H)-furanone, 1-methyl-2-piperidinone, 4-aminobutanoic acid, butyl glycolate, ethyl 2-mercaptopropanoate, ethyl 4-oxopentanoate, diethyl maleate, dimethyl maleate, dimethyl fumarate, diethyl fumarate, dimethyl adipate, and dimethyl 3-oxoglutarate.

[0051] Preferably, the organic compound is chosen from levulinic acid, citric acid, triethylene glycol, diethylene glycol, ethylene glycol, a mixture of acetic acid and dimethyl succinate.

[0052] The nitrogen-containing organic compound may be one or more compounds selected from among those containing one or more chemical functional groups, including either an amine or a nitrile group. Here, a nitrogen-containing organic compound is defined as a compound that does not contain any other heteroatoms. For example, the nitrogen-containing organic compound may be one or more compounds selected from the group consisting of ethylenediamine, diethylenetriamine, hexamethylenediamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, acetonitrile, octylamine, guanidine, or a carbazole.

[0053] The organic compound containing oxygen and nitrogen may be one or more compounds selected from among those having one or more chemical functional groups selected from among a carboxylic acid, alcohol, ether, aldehyde, ketone, ester, carbonate, amine, nitrile, imide, amide, urea, or oxime. Here, an organic compound containing oxygen and nitrogen is understood to be a compound that does not contain any other heteroatoms.As an example, the organic compound containing oxygen and nitrogen may be one or more chosen from the group consisting of 1,2-cyclohexanediaminetetraacetic acid, monoethanolamine (MEA), 1-methyl-2-pyrrolidinone, dimethylformamide, ethylenediaminetetraacetic acid (EDTA), alanine, glycine, nitrilotriacetic acid (NTA), N-(2-hydroxyethyl)ethylenediamine-N,N',N'-triacetic acid (HEDTA), diethylenetriaminepentaacetic acid (DTPA), tetramethylurea, glutamic acid, dimethylglyoxime, bicine, tricine, 2-methoxyethyl cyanoacetate, 1-ethyl-2-pyrrolidinone, 1-vinyl-2-pyrrolidinone, 1 ,3-dimethyl-2-imidazolidinone, 1-(2-hydroxyethyl)-2-pyrrolidinone, 1-(2-hydroxyethyl)-2,5-pyrrolidinedione, 1-methyl-2-piperidinone, 1-acetyl-2-azepanone, 1-vinyl-2-azepanone and 4-aminobutanoic acid.

[0054] The sulfur-containing organic compound may be one or more of the compounds having one or more chemical functions chosen from a thiol, thioether, sulfone, or sulfoxide group. For example, the sulfur-containing organic compound may be one or more of the following chosen from the group consisting of thioglycolic acid, 2,2'-thiodiethanol, 2-hydroxy-4-methylthiobutanoic acid, a sulfonated derivative of a benzothiophene or a sulfoxidized derivative of a benzothiophene, ethyl 2-mercaptopropanoate, methyl 3-(methylthio)propanoate, and ethyl 3-(methylthio)propanoate.

[0055] When present, the total content of organic compound(s) containing oxygen and / or nitrogen and / or sulfur present in the catalyst is generally between 1 and 30% by weight, preferably between 1.5 and 25% by weight, and more preferably between 2 and 20% by weight relative to the total weight of the catalyst.

[0056] The metals are advantageously introduced into the oxide support by any method known to those skilled in the art, such as co-mixing, dry impregnation, excess impregnation, or exchange impregnation. The organic compound(s) are introduced by dry or excess impregnation onto the support before, simultaneously with, or after the introduction of the metals.

[0057] During the preparation of the catalyst requiring a drying step, the drying step(s) following the introduction of the organic compound are advantageously carried out at a temperature below 200°C so as to retain preferably at least 30%, preferably at least 50%, and most preferably at least 70% of the quantity of at least said organic additive introduced, calculated on the basis of the carbon remaining on the catalyst. The remaining carbon is measured by elemental analysis according to ASTM D5373.

[0058] According to the invention, the molar ratio between group VIII elements and group VI B elements in the catalyst used in step a) is between 0.02 and 0.2, preferably between 0.05 and 0.15, and preferably between 0.06 and 0.12.

[0059] The organic compound(s) is / are advantageously introduced into an impregnation solution which, depending on the method of preparation, may be the same solution or a different solution from that containing the precursors of the metals of groups VI B and VIII, in a corresponding quantity:

[0060] - to a molar ratio of the organic compound to the sum of the elements of group VI B of the catalyst precursors of between 0.01 and 30, preferably between 0.03 and 15, preferably between 0.05 and 10 and most preferably between 0.1 and 8, calculated on the basis of the components introduced into the impregnation solution(s), and

[0061] - to a molar ratio of the organic compound to the element(s) of group VIII of the catalyst precursor (Ni) of between 0.02 and 300, preferably between 0.1 and 150, preferably between 0.5 and 100 and very preferably between 1 and 80, calculated on the basis of the components introduced into the impregnation solution(s).

[0062] When several organic compounds are present, the different molar ratios apply to each of the organic compounds present.

[0063] The hydrotreating catalyst used in step a) of the process according to the invention is chosen to orient the selectivity of the reaction as much as possible towards the deoxygenation reaction that conserves the number of carbon atoms in the fatty acid chains, i.e., the hydrodeoxygenation (HDO) pathway. This is done to maximize the recovery of the renewable feedstock into fuel fractions and the yield of hydrocarbons suitable for kerosene and / or diesel distillation, and thus limit carbon loss in the form of carbon oxides and methane. Therefore, it is preferably operated at a relatively low temperature. Maximizing the hydrogenating function also helps to limit polymerization and / or condensation reactions leading to coke formation, which would degrade the stability of the catalytic performance.

[0064] The catalyst used in step a) of the hydrotreating process according to the invention may also advantageously contain a dopant element selected from phosphorus and boron, alone or in a mixture, and preferably phosphorus. This dopant element may be introduced into the matrix or, preferably, deposited on the support. Silicon may also be deposited on the support, alone or with phosphorus and / or boron and / or fluorine.

[0065] The weight content of oxide of said dopant element in relation to the total weight of said catalyst is advantageously less than 20% and preferably less than 10% and is advantageously at least 0.001% and preferably between 0.01 and 8% by weight.

[0066] The metals of the catalysts used in step a) of hydrotreating of the process according to the invention are sulfide metals or metallic phases and preferably sulfide metals.

[0067] Using, simultaneously or successively, a single catalyst or several identical or different catalysts in step a) of the process according to the invention would not depart from the scope of the present invention. This step can be carried out industrially in one or more reactors with one or more catalytic beds.

[0068] Said hydrotreating step a) enables the hydrodeoxygenation, hydrodeazotation, and hydrodesulfurization of said feedstock. According to step b) of the process according to the invention, all of the effluent from step a) of the process according to the invention is converted in the presence of a bifunctional fixed-bed hydroisomerization catalyst, said catalyst comprising a sulfide phase of at least one metal from Group VIII in combination with at least one metal from Group VIB of the periodic table and a support comprising at least one zeolite and / or silica-alumina, said hydroisomerization step being carried out at a temperature between 250 and 500°C, at a pressure between 1 MPa and 10 MPa, at a spatial rate between 0.1 and 10 h -1 and in the presence of a total quantity of hydrogen mixed with the charge such that the hydrogen / charge ratio is between 70 and 1500 Nm 3 / m 3 dump.

[0069] Preferably, step a) hydrotreating and step b) hydroisomerizing are carried out in a single step, i.e. without any intermediate separation of the effluent from step a) hydrotreating and preferably without any gas and liquid separation step.

[0070] The operating conditions of step b) of hydroisomerization are adjusted to favor the hydroisomerization and / or hydrocracking reactions. Preferably, step b) of hydroisomerization of the process according to the invention operates at a temperature between 250°C and 450°C, and most preferably between 250°C and 400°C, at a pressure between 2 MPa and 10 MPa, and most preferably between 1 MPa and 9 MPa, at a volumetric rate advantageously between 0.2 and 7 h⁻¹. -1 and preferably between 0.5 and 5 hours -1, at a hydrogen flow rate such that the hydrogen / charge volume ratio is advantageously between 100 and 1000 normal m 3 of hydrogen per m 3 of load and preferably between 150 and 1000 normal m 3 of hydrogen per m 3 dump.

[0071] According to the invention, the hydroisomerization catalyst is a bifunctional catalyst comprising a sulfide phase of at least one metal from group VIII in combination with at least one metal from group VIB of the periodic table and a support comprising at least one zeolite and / or a silica-alumina.

[0072] The hydroisomerization catalyst is advantageously a catalyst comprising a sulfide phase of at least one Group VIII metal, preferably nickel and cobalt, alone or in a mixture, in association with at least one Group VIB metal, preferably molybdenum and tungsten, alone or in a mixture. Preferably, the hydroisomerization catalyst comprises a nickel-molybdenum sulfide phase, a nickel-molybdenum-tungsten sulfide phase, or a nickel-tungsten sulfide phase. Preferably, the hydroisomerization catalyst comprises a nickel-tungsten sulfide phase.

[0073] The content of metals from group VIB, and preferably tungsten and / or molybdenum, is advantageously between 5 and 45% by weight in oxide equivalent relative to the finished catalyst, preferably between 10 and 40% by weight, and most preferably between 15 and 35% by weight. The content of metals from group VIII, and preferably nickel and / or cobalt, of said catalyst is advantageously between 0.5 and 10% by weight in oxide equivalent relative to the finished catalyst, preferably between 1 and 8% by weight, and most preferably between 1.5 and 6% by weight. According to the invention, said catalyst is used in its sulfide form.

[0074] The catalyst used in step b) of the hydroisomerization process according to the invention may also advantageously contain a dopant element selected from phosphorus and boron, alone or in a mixture, and preferably phosphorus. This dopant element may be introduced into the matrix or, preferably, deposited on the support. Silicon may also be deposited on the support, alone or with phosphorus and / or boron and / or fluorine.

[0075] The weight content of the oxide of said dopant element is advantageously less than 20% and preferably less than 10% and is advantageously at least 0.001% and preferably between 0.01 and 8% by weight.

[0076] Metals are advantageously introduced into the catalyst by any method known to a person skilled in the art, such as co-mixing, dry impregnation, excess impregnation, or exchange impregnation.

[0077] Preferably, the hydroisomerization catalyst support comprises at least one zeolite selected from 10 MR and / or 12 MR zeolites, preferably selected from structural type zeolites MTT, MTW, *BEA, MOR, *MRE, MFI, FAU and IZM-2 zeolite, and / or a silica-alumina.

[0078] According to one variant, the hydroisomerization catalyst advantageously comprises at least one zeolite selected from structural zeolites of type MTT, preferably from ZSM-23, EU-13, alone or in mixtures; structural zeolites of type MTW, preferably from ZSM-12, TPZ-12, Theta-3, NU-13, CZH-5, alone or in mixtures; structural zeolites of type *BEA, preferably from Beta or Tschernichite alone or in mixtures; structural zeolites of type MOR, preferably from mordenite or LZ-211, alone or in mixtures; structural zeolites of type MFI, preferably from ZSM-5; structural zeolites of type *MRE, preferably ZSM-48; and structural zeolites of type FAU, preferably... zeolite Y and possibly at least one oxide binder.

[0079] Structural codes are defined in the International Zeolite Association (IZA) classification.

[0080] The zeolite may also be IZM-2, whose structural code is not known.

[0081] Preferably, the zeolite is selected from ZSM-12, IZM-2, and ZSM-23 zeolites, alone or in mixtures, and preferably from ZSM-12 and IZM-2 zeolites, alone or in mixtures. The oxide binder is advantageously selected from silica (SiCh), alumina (Al₂O₃), clays, titanium dioxide (TiCh), boron dioxide (B₂O₃), and zirconia (ZrCl₂), alone or in mixtures. Preferably, the binder is selected from silica, silica alumina, and alumina, and even more preferably, the binder is alumina in all its forms known to those skilled in the art, such as gamma alumina.

[0082] Preferably, said support comprises between 10 and 50% by weight of zeolite, preferably between 12% and 45% by weight, and most preferably between 15% and 40% by weight, relative to the total weight of said support.

[0083] According to another variant, the support for the hydroisomerization catalyst is preferably made of silica-alumina.

[0084] The silica-alumina support advantageously has a total pore volume between 0.1 and 1.5 cm³ 3 . g -1 preferably between 0.2 and 0.8 cm 3 . g -1 and in a particularly preferred manner between 0.3 and 0.6 cm 3 . g -1 The total pore volume is measured by mercury porosimetry according to ASTM D4284 with a wetting angle of 140°, as described in the book Rouquerol F.; Rouquerol J.; Singh K. “Adsorption by Powders & Porous Solids: Principle, methodology and applications”, Academic Press, 1999, for example using an Autopore III™ instrument from the brand Micromeritics™.

[0085] The specific surface area of ​​the silica-alumina support is advantageously between 5 and 400 m² 2 .g' 1preferably between 100 and 350 m 2 .g' 1 , preferably between 200 and 300 m 2 .g' 1 The specific surface area is determined in the present invention by the BET method according to ASTM D3663, a method described in the same work cited above.

[0086] The silica content in the substrate is at most 50% by weight relative to the total weight of the substrate, most often less than or equal to 45% by weight, preferably less than or equal to 40%. Preferably, the silica content in the substrate is between 10 and 50% by weight, preferably between 15 and 40% by weight, and particularly preferably between 20 and 35% by weight relative to the total weight of the substrate.

[0087] Sources of silicon are well known to those skilled in the art. Examples include silicic acid, silica in powder form or colloidal form (silica sol), and tetraethyl orthosilicate Si(OEt)4.

[0088] According to another variant, the hydroisomerization catalyst support is a silica-alumina that may advantageously also contain a zeolite. In this case, all sources of zeolites and all associated preparation methods known to those skilled in the art may be incorporated. Preferably, the zeolite is selected from the FAU, BEA, ISV, IWR, IWW, MEI, and UWY groups, and even more preferably, from the FAU and BEA groups, such as zeolite Y and / or beta, and particularly preferably such as zeolite USY and / or beta. When zeolite is present, its content is from 0.1 to 50 wt% relative to the total weight of the support, preferably from 0.1 to 10 wt%.

[0089] The support material is advantageously in the form of irregular, non-spherical beads, extrudates, pellets, or agglomerates, the specific shape of which may result from a crushing step. Step a) hydrotreating and step b) hydroisomerization may advantageously be carried out in a single reactor or in separate reactors, preferably in a single reactor.

[0090] In the case where steps a) and b) are carried out in a single reactor, one or more catalytic beds comprising at least one hydrotreating catalyst may be implemented. Similarly, one or more catalytic beds comprising at least one hydroisomerization catalyst according to the invention may also be implemented.

[0091] The proportion of the hydrotreating catalyst in the hydrotreating step a) advantageously represents between 10 and 90%, preferably between 50 and 90% and preferably between 55 and 85% of the total catalyst volume.

[0092] The proportion of the hydroisomerization catalyst in the hydroisomerization step b) advantageously represents between 10 and 90%, preferably between 10 and 50% and preferably between 15 and 45% of the total catalyst volume.

[0093] The total volume of catalyst is understood to be the sum of the volume of hydrotreating catalyst and the volume of hydroisomerization catalyst contained respectively in steps a) and b), whether steps a) and b) are carried out in a single reactor or in several reactors.

[0094] In accordance with step c) of the process according to the invention, the effluent from step b) undergoes a fractionation step enabling the recovery of at least a diesel fraction.

[0095] Preferably said step c) includes a gas / liquid separation step followed by a water removal step.

[0096] Said step c) may also advantageously include an atmospheric distillation step and possibly a vacuum distillation, to obtain at least a middle distillate fraction.

[0097] The purpose of said step c) is to separate the gases from the liquid, to remove the water and in particular, to recover the hydrogen-rich gases which may also contain light gases such as the Ci-C4 cut and at least one diesel cut, possibly at least one kerosene cut and possibly at least one naphtha cut.

[0098] At least a portion of the middle distillate fraction can advantageously be recycled in step a) of hydrotreating.

[0099] The examples below illustrate the invention without limiting its scope. EXAMPLES

[0100] Examples 1 to 4 describe the preparation of C1 to C4 catalysts.

[0101] Examples 5 to 11 describe the evaluation in hydrotreating and hydroisomerization of a feed from a renewable source implementing a catalyst chain including the hydrotreating catalyst C1 with hydroisomerization catalysts C2 to C6 respectively.

[0102] Example 1: Preparation of a hydrotreating catalyst (C1) (not according to the invention)

[0103] On 100 grams of an A1 alumina support exhibiting a loss on ignition of 4.1% by weight, a BET surface area of ​​263 m² 2 / g, a pore volume measured by mercury porosimetry of 0.66 mL / g and a mean pore diameter of 9.7 nm defined as the median diameter by volume by mercury porosimetry and which is in extruded form, nickel, molybdenum, and phosphorus are added. The A1 support has a water absorption volume of 0.72 mL / g. The impregnation solution is prepared by dissolving at 90°C 29.2 grams of molybdenum oxide (Merck™, purity > 99.5% wt), 2.4 grams of nickel hydroxycarbonate (Merck™, purity 99.9% wt) and 11.2 grams of an orthophosphoric acid solution (Merck™, 85% wt in water) in 64.2 mL of distilled water. The molar ratio between the elements of group VIII and group VIB is 0.1. After dry impregnation, the extrudates are left to mature in a water-saturated atmosphere for 24 h at room temperature, then they are dried at 90°C for 2 h, before being calcined under air at 450°C for 4 hours.The calcined catalyst thus obtained is denoted C1. The final composition of catalyst C1 expressed in terms of oxides is then as follows: MoC>3= 22 + / - 0.2 (% by weight), NiO = 1.1 + / - 0.1 (% by weight) and P2Os= 5.2 +- 0.1 (% by weight).

[0104] Example 2: Preparation of a hydrotreating catalyst (C2) (not according to the invention)

[0105] Nickel, molybdenum, and phosphorus are added to the same A1 alumina support shown in Example 1. The impregnation solution is prepared by dissolving 31.1 grams of molybdenum oxide (Merck™, purity > 99.5 wt.), 10.1 grams of nickel hydroxycarbonate (Merck™, purity 99.9 wt.), and 11.9 grams of orthophosphoric acid solution (Merck™, 85 wt. in water) at 90°C in 63.9 mL of distilled water. The molar ratio between the Group VIII and Group VIB elements is 0.4. After dry impregnation, the extrudates are left to mature in a water-saturated atmosphere for 24 h at room temperature, then they are dried at 160°C for 1 hour before being dry impregnated again with an aqueous solution containing 26.1 grams of triethylene glycol (TEG, Merck™) so that the TEG / Mo molar ratio is 0.8 and the TEG / Ni molar ratio is 2. A final drying is then applied to the extrudates for one hour under air at 90°C.The additively obtained catalyst is denoted C2. The final composition of catalyst C2 expressed in terms of oxides is then as follows: MoC>3= 22 + / - 0.2 (% by weight), NiO = 4.6 + / - 0.1 (% by weight) and P20s= 5.2 +- 0.1 (% by weight).

[0106] Example 3: Preparation of a hydrotreating catalyst (C3) (not according to the invention)

[0107] Nickel, molybdenum, and phosphorus are added to the same A1 alumina support shown in Example 1. The impregnation solution is prepared by dissolving 29.2 grams of molybdenum oxide (Merck™, purity > 99.5 wt.), 0.5 grams of nickel hydroxycarbonate (Merck™, purity 99.9 wt.), and 11.2 grams of orthophosphoric acid solution (Merck™, 85 wt. in water) at 90°C in 65.3 mL of distilled water. The molar ratio between the Group VIII and Group VI B elements is 0.01. After dry impregnation, the extrudates are left to mature in a water-saturated atmosphere for 24 hours at room temperature, then dried at 160°C for 1 hour before being dry-impregnated again with an aqueous solution containing triethylene glycol (TEG, Merck™) so that the TEG / Mo molar ratio is 0.8. A final drying process is then applied to the extrudates for one hour in air at 90°C. The resulting additive-treated catalyst is designated C3.The final composition of the C3 catalyst expressed in terms of oxides is then as follows: MoO3 = 22 + / - 0.2 (% by weight), NiO = 0.2 + / - 0.1 (% by weight) and P2Os = 5.2 + / - 0.1 (% by weight).

[0108] Example 4: Preparation of a hydrotreating catalyst (C4) (according to the invention)

[0109] Nickel, molybdenum, and phosphorus are added to the same A1 alumina support shown in Example 1. The impregnation solution is prepared by dissolving 29.2 grams of molybdenum oxide (Merck™, purity > 99.5 wt.), 2.4 grams of nickel hydroxycarbonate (Merck™, purity 99.9 wt.), and 11.2 grams of orthophosphoric acid solution (Merck™, 85 wt. in water) at 90°C in 64.2 mL of distilled water. The molar ratio between the Group VIII and Group VI B elements is 0.1. After dry impregnation, the extrudates are left to mature in a water-saturated atmosphere for 24 h at room temperature, then they are dried at 160°C for 1 hour before being dry impregnated again with an aqueous solution containing 26.1 grams of triethylene glycol (TEG, Merck™) so that the TEG / Mo molar ratio is 0.8. A final drying is then applied to the extrudates for one hour under air at 90°C.The additive catalyst thus obtained is denoted C4. The final composition of catalyst C4 expressed in terms of oxides is then as follows: MoO3= 22 + / - 0.2 (% by weight), NiO = 1.1 + / - 0.1 (% by weight) and P2Os= 5.2 +- 0.1 (% by weight).

[0110] Example 5: Preparation of a hydrotreating catalyst (C5) (according to the invention)

[0111] On the same A1 alumina support as shown in Example 1, nickel, molybdenum, and phosphorus are added. The impregnation solution is prepared by dissolving at 90°C 29.2 grams of molybdenum oxide (Merck™, purity > 99.5% wt), 2.4 grams of nickel hydroxycarbonate (Merck™, purity 99.9% wt), 11.2 grams of an orthophosphoric acid solution (Merck™, 85% wt in water), and 26.1 grams of triethylene glycol (TEG, Merck™) in 41.9 mL of distilled water. After dry impregnation, the extrudates are left to mature in a water-saturated atmosphere for 24 h at room temperature, then they are dried at 90°C for 2 h. The molar ratio between the elements of group VIII and group VI B is 0.1 and 0.8 between triethylene glycol and molybdenum and 8 between triethylene glycol and nickel.After dry impregnation, the extrudates are left to mature in a water-saturated atmosphere for 24 h at room temperature, then they are dried at 120°C for 1 hour. The resulting additive catalyst is designated 05. The final composition of the C5 catalyst, expressed as oxides, is as follows: MoOs = 22 + / - 0.2 (wt %), NiO = 1.1 + / - 0.1 (wt %) and P2Os = 5.2 + / - 0.1 (wt %).

[0112] Example 6: Preparation of a hydrotreating catalyst (C6) (according to the invention)

[0113] Nickel, molybdenum, and phosphorus are added to the same A1 alumina support shown in Example 1. The impregnation solution is prepared by dissolving 29.6 grams of molybdenum oxide (Merck™, purity > 99.5 wt.), 2.4 grams of nickel hydroxycarbonate (Merck™, purity 99.9 wt.), and 11.3 grams of orthophosphoric acid solution (Merck™, 85 wt. in water) in 64.2 mL of distilled water at 90°C. The molar ratio between the Group VIII and Group VI B elements is 0.1. After dry impregnation, the extrudates are left to mature in a water-saturated atmosphere for 24 h at room temperature, and then dried at 160°C for 1 hour.The dried, impregnated support of the C6 catalyst is then treated by dry impregnation with a solution containing a mixture of dimethyl succinate (DMSU) and acetic acid (75% purity), with a DMSU / Mo molar ratio of 0.85, an acetic acid / Mo molar ratio of 5.7, a DMSU / Ni molar ratio of 8.5, and an acetic acid / Ni molar ratio of 57.1. The catalyst undergoes a further maturation step of 3 hours at 20°C in air, followed by drying in a flow-through bed oven at 120°C for 3 hours. A final drying is then applied to the extrudates for one hour in air at 90°C. The resulting treated catalyst is designated C6. The final composition of the C6 catalyst expressed in terms of oxides is then as follows: MoOs= 22 + / - 0.2 (% by weight), NiO = 1.1 + / - 0.1 (% by weight) and P2Os= 5.2 +- 0.1 (% by weight).

[0114] Example 7: Preparation of a hydroconversion catalyst according to the invention (C7)

[0115] For the preparation of the C7 catalyst support, a mixture of alumina gel and ZSM-12 zeolite is shaped by kneading and extrusion through a die with 1.5 mm diameter quadrilobe orifices, dried at 80°C, and calcined at 550°C. The ZSM-12 content in the support is 19 wt%. The support is in extruded form. Nickel and tungsten are added. The zeolite-containing support has a water absorption volume of 0.77 mL / g. The impregnation solution is prepared by dissolving 38.9 grams of ammonium metatungstate and 17.3 grams of nickel nitrate in 75.3 mL / g. After dry impregnation, the extrudates are allowed to mature in a water-saturated atmosphere for

[0116] They are left at room temperature for 24 hours, then dried at 120°C for 5 hours, before being calcined in air at 450°C for 4 hours. The calcined catalyst thus obtained is designated C8. The final composition of catalyst C7, expressed as oxides, is then as follows: WOa=

[0117] 25 + / - 0.2 (% by weight) and NiO = 3.2 + / - 0.1 (% by weight).

[0118] Example 8: Preparation of a hydroconversion catalyst according to the invention (C8)

[0119] On 100 grams of an amorphous silica-alumina support exhibiting a loss on ignition of 1.5% by weight, a BET surface of 240 m² 2The porosity, measured by mercury porosimetry at 0.46 mL / g, is present in the "extruded" form. Nickel and tungsten are added. The silica-alumina support has a water absorption volume of 0.54 mL / g. The impregnation solution is prepared by dissolving 38.9 grams of ammonium metatungstate and 17.3 grams of nickel nitrate in 56.0 mL of distilled water. After dry impregnation, the extrudates are left to mature in a water-saturated atmosphere for 24 hours at room temperature, then dried at 120°C for 5 hours, before being calcined in air at 450°C for 4 hours. The resulting calcined catalyst is designated C8. The final composition of the C8 catalyst expressed as oxides is then as follows: WOa= 25 + / - 0.2 (% by weight) and NiO = 3.2 + / - 0.1 (% by weight).

[0120] Examples 9 to 14: Evaluation in hydrotreating and hydroconversion of a feed from a renewable source implementing the sequence of hydrotreating catalysts C1 to C6 respectively with the hydroconversion catalyst C7

[0121] In a single temperature-controlled reactor designed to ensure isothermal operation, a fixed-bed catalyst is used, containing 60% by volume of hydrotreating catalyst C1 and 40% by volume of hydroconversion catalyst C7, relative to the total catalyst volume. Hydrotreating catalyst C1 is placed at the reactor inlet, and hydroconversion catalyst C7 is placed at the outlet. The catalysts are pre-sulfurized, and the hydrotreating and hydroconversion of pre-refined rapeseed oil with a density of 920 kg / m³ is then carried out. 3exhibiting an oxygen content of 11 wt%. The fatty acid distribution of the rapeseed oil is detailed in Table 1. During the hydrotreating step, this feedstock is treated with dimethyl disulfide to adjust its sulfur content to 50 ppm wt% to maintain the catalyst in a sulfide state. Table 1

[0122] Table 1: Characteristics of rapeseed oil used as feedstock for hydrotreating

[0123] Prior to the feedstock hydrotreating stage, the catalysts are sulfided in-situ in the unit, with isane to which 2% by weight of dimethyl disulfide has been added, under a total pressure of 7 MPa, at a hydrogen / diesel fuel ratio of 1000 Nm 3 by m 3 The volume of sulfidation charge per total volume of catalyst per hour is set at 1. Sulfuration is carried out for 12 hours at 350°C, with a temperature ramp of 10°C per hour.

[0124] After sulfidation, the unit's operating conditions are adjusted to perform hydrotreating and hydroconversion of the feed: - WH (feed volume / total catalyst volume / hour): 0.41 h' 1 ,

[0125] - Total working pressure: 7 MPa,

[0126] - hydrogen / charge ratio: 1000 Nm 3 hydrogen / m 3 dump,

[0127] The hydrogen used is supplied by Air Product and has a purity exceeding 99.999% by volume. Temperature steps at 340 to 355°C are performed to vary the severity of the hydroconversion and achieve a target cloud point of -7°C for the liquid effluent. At the unit outlet, online gas chromatography analysis and a gas meter allow for the calculation of the mass of light hydrocarbons produced and present in the hydrogen stream.

[0128] The liquid effluent is collected for 12 hours. This liquid effluent is then weighed and analyzed by simulated distillation (ASTM D2887) to determine the average distillate yield (120°C cut). + , corresponding to hydrocarbons present in the gas and liquid fraction with a boiling point above 120°C).

[0129] The average distillate yield is calculated as follows:

[0130] Yield (average distillate) = [(mass of liquid effluent * % cut at 120°C]] + / 100 + mass [C8-C13]gas) / (mass of liquid effluent + mass of light hydrocarbons (gas) + mass of water + mass of COx)] * 100

[0131] The mass of liquid effluent corresponds to the mass of the liquid recipe accumulated over 12 hours.

[0132] The %coupe 120°C+ is obtained by simulated distillation: mass fraction of the liquid effluent whose boiling point is greater than 120°C.

[0133] The [C8-C13]gas mass is obtained by online gas chromatography analysis of the hydrogen flow exiting the unit. It corresponds to the mass of hydrocarbon compounds with a number of carbon atoms between 8 and 13.

[0134] The mass of water is the sum of the mass of settled water present in the liquid effluent and the mass of water present in the gases and analyzed online by gas chromatography.

[0135] The mass of COx is the mass of carbon oxides (CO and CO2) present in the gas phase; it is determined by online analysis using gas chromatography.

[0136] Furthermore, the trouble point is determined by the ASTM D5773 method.

[0137] According to example 9 (not in accordance with the invention), the first zone is loaded with catalyst C1 (60% of the total catalyst volume), then the second with catalyst C7 (40% of the total catalyst volume).

[0138] According to example 10 (not in accordance with the invention), the first zone is loaded with catalyst C2 (60% of the total catalyst volume), then the second with catalyst C7 (40% of the total catalyst volume).

[0139] According to Example 11 (not in accordance with the invention), the first zone is loaded with catalyst C3 (60% of the total catalyst volume), and then the second with catalyst C7 (40% of the total catalyst volume). According to Example 12 (in accordance with the invention), the first zone is loaded with the compliant catalyst C4 (60% of the total catalyst volume), and then the second with catalyst C7 (40% of the total catalyst volume).

[0140] According to example 13 (according to the invention), the first zone is loaded with the compliant C5 catalyst (60% of the total catalyst volume), then the second with the C7 catalyst (40% of the total catalyst volume).

[0141] According to example 14 (according to the invention), the first zone is loaded with the compliant C6 catalyst (60% of the total catalyst volume), then the second with the C7 catalyst (40% of the total catalyst volume).

[0142] The sequence between catalyst C1 and catalyst C7 is defined as the reference. The performance criteria are as follows:

[0143] - Conversion activity expressed as the temperature increase relative to the reference required to reach a cloud point of -7°C in the liquid effluent. A negative value indicates an increase in activity.

[0144] - Average distillate yields obtained for a liquid effluent cloud point of -7°C. This is expressed as a deviation from the reference. A negative value indicates a yield loss.

[0145] The main characteristics of the effluents produced and the associated operating conditions are reported in Table 2.

[0146] Table 2 Table 2: Main characteristics of effluents produced by hydrotreatment and hydroisomerization

[0147] The combination of catalyst C2 and catalyst C7 (example 10 not in accordance with the invention) allows the production of a middle distillate cut having a cloud point of -7°C with a gain in converting activity of 3°C compared to the base case but the yield in middle distillate is reduced by 4 points.

[0148] The combination of catalyst C3 and catalyst C7 (example 11 not in accordance with the invention) allows the production of a middle distillate cut having a cloud point of -7°C with a loss of converting activity of 5°C compared to the base case while increasing the yield in middle distillate by 3 points.

[0149] The combination of catalyst C4 and catalyst C7 (example 12 according to the invention) allows the production of a middle distillate cut having a cloud point of -7°C with a gain in converting activity of 3°C compared to the base case while increasing the yield in middle distillate by 2 points.

[0150] The combination of catalyst C4 and catalyst C7 (example 13 according to the invention) allows the production of a middle distillate cut having a cloud point of -7°C with a gain in converting activity of 2°C compared to the base case while increasing the yield in middle distillate by 2 points.

[0151] The combination of catalyst C5 and catalyst C7 (example 14 according to the invention) allows the production of a middle distillate cut having a cloud point of -7°C with a gain in converting activity of 3°C compared to the base case while increasing the yield in middle distillate by 2 points.

[0152] It therefore appears that the implementation of a catalyst chain in a hydrotreating and hydroisomerizing process of a vegetable oil operating in one step according to the present invention and in particular that the implementation in the hydrotreating step of a specific catalyst comprising at least one metal of group VIII, in combination with at least one metal of group VI B and having a molar ratio between the elements of group VIII and group VI B of between 0.02 and 0.2, at least one specific organic additive and an oxide support comprising at least alumina makes it possible to obtain an improved activity of said hydroisomerizing catalyst, while increasing the yields of average distillates compared to the implementation of catalysts conventionally used in the prior art in a one-step process.

[0153] Examples 15 and 16: Evaluation of a feedstock from a renewable source using hydrotreating and hydroconversion catalysts, respectively C1 or C4, and hydroconversion catalyst C8. The reactor is temperature-controlled to ensure isothermal, fixed-bed operation. The reactor is loaded with 60% by volume of hydrotreating catalyst C1 and 40% by volume of hydroconversion catalyst C8 relative to the total catalyst volume. Hydrotreating catalyst C1 is placed at the reactor inlet, and hydroconversion catalyst C8 is placed in the second position (at the reactor outlet). The operating conditions, analyses, and calculations performed are reproduced from Examples 9 to 14.

[0154] According to Example 15 (not in accordance with the invention), the first zone is loaded with catalyst C1 (60% of the total catalyst volume), and then the second zone with catalyst C8 (40% of the total catalyst volume). According to Example 16 (in accordance with the invention), the first zone is loaded with catalyst C4 (60% of the total catalyst volume), and then the second zone with catalyst C8 (40% of the total catalyst volume).

[0155] The sequence between catalyst C1 and catalyst C8 is defined as the reference

[0156] The main characteristics of the effluents produced and the associated operating conditions are reported in Table 3.

[0157] Table 3

[0158] Table 3: Main characteristics of effluents produced by hydrotreatment and hydroisomerization The combination of catalyst C4 and catalyst C8 (example 16 according to the invention) allows the production of a diesel cut having a cloud point of -7°C with a gain in converting activity of 5°C compared to the base case while increasing the yield in average distillate by 5 points.

Claims

DEMANDS 1. A process for treating a feedstock from a renewable source comprising at least the following steps: a) a hydrotreating step of said feedstock in the presence of at least one fixed-bed catalyst, said hydrodeoxygenation catalyst comprising at least one metal from Group VIII, in combination with at least one metal from Group VI B of the periodic table, the molar ratio between the elements of Group VIII and Group VI B being between 0.02 and 0.2, at least one organic additive and a support comprising at least one oxide, at a temperature between 200 and 450°C, at a pressure between 1 MPa and 10 MPa, at a space-hour velocity between 0.1 h-1 and 10 h-1 and in the presence of a total quantity of hydrogen mixed with the feedstock such that the hydrogen / feedstock ratio is between 70 and 1700 N m3 of hydrogen / m3 of feedstock,b) a hydroisomerization step of all the hydrocarbon liquid effluent from step a) in the presence of a fixed-bed bifunctional hydroisomerization catalyst, said catalyst comprising a sulfide phase of at least one metal from Group VIII in combination with at least one metal from Group VIB of the periodic table and a support comprising at least one zeolite and / or silica-alumina, said hydroisomerization step being carried out at a temperature between 250°C and 500°C, at a pressure between 1 MPa and 10 MPa, at a spatial velocity between 0.1 and 10 h-1 and in the presence of a total quantity of hydrogen mixed with the feed such that the hydrogen / feed ratio is between 70 and 1500 Nm3 / m3 of feed, c) a fractionation step of the effluent from step b) to obtain at least one diesel fraction.

2. A method according to claim 1 wherein the feedstock from renewable sources is selected from oils and fats of vegetable or animal origin, or mixtures of such feedstocks, containing triglycerides and / or free fatty acids and / or esters.

3. A method according to claim 1 or 2, wherein in step a), the feedstock is brought into contact with a fixed-bed catalyst at a temperature between 220 and 350°C, at a pressure between 1 MPa and 6 MPa, and at a spatial velocity between 0.1 h -1 and 10 a.m. 1 , in the presence of a total quantity of hydrogen mixed with the charge such that the hydrogen / charge ratio is between 150 and 1500 Nm 3 hydrogen / m 3 dump.

4. A method according to any one of claims 1 to 3, wherein the hydrotreating catalyst support used in step a) comprises at least one oxide selected from titanium dioxide, alumina, silica, and zirconia, alone or in mixtures, preferably said support comprises at least alumina and preferably, said support is made of alumina and preferably comprises and is preferably made of alumina r|, 5 or y and preferably made of alumina r], 5 or y.

5. A process according to any one of claims 1 to 4 wherein said hydrotreating catalyst implemented in step a) comprises at least one metal from group VIII selected from nickel and cobalt, in combination with at least one metal from group VI B selected from molybdenum and tungsten, taken alone or in mixture.

6. A process according to any one of claims 1 to 5 wherein said hydrotreating catalyst implemented in step a) comprises at least one organic additive selected from organic compounds containing oxygen, organic compounds containing nitrogen, organic compounds containing oxygen and nitrogen and organic compounds containing sulfur, alone or in mixture.

7. A process according to claim 6 wherein said hydrotreating catalyst comprises an organic compound selected from levulinic acid, citric acid, triethylene glycol, diethylene glycol, ethylene glycol, a mixture of acetic acid and dimethyl succinate.

8. A method according to any one of the preceding claims wherein the molar ratio of metal(ux) of groups VIB and VIII in the hydrotreating catalyst used in step a) is between 0.05 and 0.15, and preferably between 0.06 and 0.

12.

9. A method according to any one of claims 1 to 8, wherein the organic compound(s) is / are introduced into an impregnation solution, which may be the same solution or a different solution from that containing the precursors of metals from groups VIB and VIII, in a corresponding quantity: - to a molar ratio of the organic compound to the sum of the elements of group VIB of the catalyst precursors of between 0.01 and 30, preferably between 0.03 and 15, preferably between 0.05 and 10 and most preferably between 0.1 and 8, calculated on the basis of the components introduced into the impregnation solution(s), and - to a molar ratio of the organic compound to the element(s) of group VIII of the catalyst precursor (Ni) of between 0.02 and 300, preferably between 0.1 and 150, preferably between 0.5 and 100 and very preferably between 1 and 80, calculated on the basis of the components introduced into the impregnation solution(s).

10. A process according to any one of claims 1 to 9, wherein the hydrotreating step (a) and the hydroisomerization step (b) are carried out in a single step, i.e., without any intermediate separation of the effluent from step a) of hydrotreatment and preferably without any gas and liquid separation step.

11. A process according to any one of the preceding claims wherein the hydroisomerization catalyst used in step b) comprises at least one zeolite selected from 10 MR and / or 12 MR zeolites selected from structural type zeolites MTT, MTW, *BEA, MOR, *MRE, MFI; FAU and IZM-2 zeolite and / or a silica-alumina.

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