PROCESS FOR CO-PRODUCTION OF KEROSENE AND RENEWABLE DIESEL BY HYDROPROCESSING IN 2 STAGES USING A SPECIFIC CATALYST FOR THE HYDROCONVERSION STAGE WITHOUT RECYCLE

Abstract

The present invention describes a process for treating a feedstock from a renewable source comprising a step a) of hydrotreatment, a step b) of separating at least a portion of the effluent from step a) into at least one light fraction and at least one hydrocarbon effluent, a step c) of hydroconversion of the hydrocarbon effluent from step c) using at least one specific bifunctional catalyst comprising at least one noble metal from group VIII chosen from platinum and palladium and a support comprising at least one zeolite chosen from zeolites with structural code MTW, and zeolite IZM-2 alone or as a mixture, and at least one binder, and a step d) of separating the effluent from step c) which makes it possible to separate at least one gaseous fraction, and at least one liquid hydrocarbon effluent, a step e) of fractionating the hydrocarbon effluent from step d) into at least one diesel cut and one cut kerosene,without recycling in hydrotreatment step a) and / or hydroconversion step c), of all or part of the effluents from hydroconversion step c), of the effluents from separation step d) and / or of the effluents from fractionation step e). Figure 1 to be published,

Description

Title of the invention: PROCESS FOR THE CO-PRODUCTION OF KEROSENE AND RENEWABLE DIESEL OIL BY HYDRO- 2-STAGE PROCESSING USING A SPECIFIC CATALYST FOR THE HYDROCONVERSION STAGE WITHOUT RECYCLE Field of invention

[0001] The search for new sources of renewable energy for the production of fuels constitutes a major challenge in order to both meet the demand for fuel and take into account environmental concerns.

[0002] In this respect, the recovery of feedstocks from renewable sources into fuels has seen a very strong resurgence of interest in recent years. Among these feedstocks, we can cite for example vegetable oils (for example palm, rapeseed, soybean), animal fats, used cooking oils, oils of microbial origin (for example from algae), fish oils, long paraffins (waxes) from the Fischer-Tropsch process, raw or having undergone prior treatment, as well as mixtures of such feedstocks. These feedstocks mostly contain chemical structures of the triglyceride or ester or fatty acid type, the structure and the length of the hydrocarbon chain of the latter being compatible with the hydrocarbons present in diesel and kerosene.

[0003] One possible route is the catalytic transformation of the feedstock from a renewable source into deoxygenated paraffinic fuel in the presence of hydrogen (hydrotreatment). Many metal or sulfide catalysts are known to be active for this type of reaction.

[0004] These processes for hydrotreating 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.

[0005] The use of solids based on transition metal sulfides allows the production of paraffins from ester-type molecules according to two reaction pathways:

[0006] - hydrodeoxygenation leading to the formation of water by consumption of hydrogen and the formation of hydrocarbons with a carbon number (Cn) equal to that of the initial fatty acid chains,

[0007] - decarboxylation / decarbonylation leading to the formation of carbon oxides (carbon monoxide and dioxide: CO and CO2) and the formation of hydrocarbons having one less carbon (Cn.i) compared to the initial fatty acid chains.

[0008] The liquid effluent from these hydrotreatment processes, after separation, is essentially made up of n-paraffins and is substantially free of sulfur, nitrogen and oxygen impurities. After hydrotreatment and gas separation, the sulfur content is typically between 1 and 20 ppm by weight, the nitrogen content is generally between 0.2 and 30 ppm by weight and the oxygen content is generally less than 2000 ppm by weight. The paraffins have a number of carbon atoms typically between 9 and 25, which is mainly dependent on the composition of the feedstock to be hydrotreated.

[0009] However, this liquid effluent cannot generally be incorporated as is into the kerosene or diesel pool, in particular due to insufficient cold properties and / or boiling temperatures that are too high. Indeed, the paraffins present lead to high pour points and therefore to freezing phenomena for uses at low temperatures. For example, eicosane (linear paraffin with 20 carbon atoms, C2oH42) has a boiling point equal to 340°C and a melting point of 37°C. The boiling point of eicosane is thus compatible with incorporation into a diesel pool, but its melting temperature can generate freezing problems and limit its use. As an illustration, the filterability limit temperature for winter diesel is a maximum of -15°C.Furthermore, the boiling temperature of eicosane makes it unincorporable into the kerosene pool, for which the final temperature of the distillation curve must be less than 300°C.

[0010] Depending on the incorporation rate and the preferred fuel pool (diesel or kerosene) that are targeted, it may be necessary to carry out a hydroconversion step (hydroisomerization and / or hydrocracking reactions) to transform the linear paraffins in the hydrotreated liquid effluent. Hydroisomerization makes it possible to convert a linear paraffin into a branched paraffin while preserving the number of carbon atoms in the molecule. This makes it possible to improve the cold properties of the effluent because branched paraffins have better cold properties than linear paraffins. For example, nonadecane has a melting point of 32°C while one of its monobranched isomers, 7-methyl-octadecane, has a melting point of -16°C. Hydrocracking makes it possible to convert a linear paraffin into linear or branched paraffins of lower molecular weight.This allows the distillation curve of the effluent to be adjusted as needed to make it compatible with the kerosene pool. As an illustration, the hydrocracking of one eicosane molecule can lead to the production of two 2-methylnonane molecules. The boiling point of 2-methylnonane is 167°C, which is compatible with incorporation into the kerosene pool. The hydroconversion step is carried out on a bifunctional catalyst having both a hydro / dehydrogenating function and a Bronsted acid function. The conditions . Operating procedures can be adapted to promote hydroisomerization or hydrocracking reactions as required. In all cases it is desirable to minimize the production of cracking products too light to be incorporated into the kerosene or diesel pool.

[0011] The appropriate choice of the acid phase makes it possible to promote the isomerization of long linear paraffins and to minimize cracking. Thus, the shape selectivity of one-dimensional medium-pore zeolites (10 MR) such as ZSM-22, ZSM-23, NU-10, ZSM-48, ZBM-30 zeolites makes their use particularly suitable for obtaining catalysts selective for isomerization. Other acid phases of zeolitic or non-zeolitic type such as halogenated aluminas (chlorinated or fluorinated in particular), phosphorus-containing aluminas, silica-aluminas or even silica-containing aluminas can also be used.

[0012] However, it is well known that factors other than the acid phase have an impact on the activity and selectivity of a bifunctional catalyst. The hydroisomerization and hydrocracking of normal paraffins have thus been the subject of numerous academic studies since the original work of the sixties by Weisz or Coonradt and Garwood. The most commonly accepted mechanism involves firstly that the n-paraffin is dehydrogenated to n-olefin on the hydro-dehydrogenating phase and then, after diffusion to the acid phase, that it is protonated to carbenium ion. After structural rearrangement and / or [3-scission, the carbenium ions desorb from the acid phase in the form of olefins after deprotonation. Then, after diffusion to the hydro-dehydrogenating phase, the olefins are hydrogenated to form the final reaction products.It is then necessary to have a sufficiently active hydro / dehydrogenating function with respect to the acid function to, on the one hand, rapidly supply the acid phase with olefins and, on the other hand, to rapidly hydrogenate the olefinic intermediates after their reaction on the acid phase. This makes it possible, on the one hand, to maximize the activity of the catalyst and, on the other hand, to favor hydroisomerization compared to hydrocracking when the first reaction is desired, or to limit the production of cracking products that are too light when the hydrocracking reaction is desired. 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.

[0013] The proximity between the two functions of the catalyst can also have an impact on the performance of the bifunctional catalyst. Thus, Zecevic et al. (Nature, 2015, 528, 245-254) recently studied the impact of platinum localization on the performance in hydroisomerization of long paraffins (n-decane, n-nonadecane, pristane) of a bifunctional catalyst using USY zeolite as the acid phase and an alumina matrix. It is observed that the bifunctional catalyst for which platinum is deposited on alumina is systematically more selective in isomerization than the catalyst for which platinum is deposited in the zeolite. In view of these results, the skilled person is therefore inclined to favor a localization of the hydrogenating function on the alumina matrix rather than on the acid phase to improve the selectivity in isomerization. From an activity point of view, the localization of platinum on the alumina matrix has a variable impact depending on the long paraffin considered: positive impact with regard to n-decane, marginal impact with regard to n-nonadecane and finally negative impact with regard to pristane.

[0014] Noble metals (Pt, Pd) or group VIA transition metals (Mo, W) associated with group VIII transition metals (Ni, Co) can act as a hydrogenating function for the catalyst. The noble metals are used in their reduced form while the transition metals are used in a sulfurized form. For the latter, there is a known synergistic effect between the group VIA transition metals and the group VIII transition metals, generally attributed to the decoration of the group VIA sulfide phases by the group VIII transition metals. We then speak of molybdenum or tungsten sulfide phases promoted by nickel or cobalt ("CoMoS", "NiMoS", "NiWS"). This synergistic effect results in an increase in the catalytic activity of the promoted phase compared to a non-promoted phase.

[0015] The choice of the nature of the hydrogenating function, of the noble metal or sulfide type, is a function of different criteria, of an economic nature (the price of noble metals is significantly higher than that of transition metals of groups VIA and VIII) or of a chemical nature (impact of the presence of contaminants). Thus, the hydrogenating 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. Conversely, the hydrogenating activity of transition metal sulfides is higher than that of noble metals when the partial pressure of H2S in the reaction medium becomes significant (C. Marcilly, Acid-Base Catalysis, volume 2, 2003, Technip editions).

[0016] Patent US2022 / 0127537 teaches a process for hydrotreating a renewable feedstock. Said process comprises a step of hydrotreating the feedstock in the presence of hydrogen and a hydrotreating catalyst to deoxygenate said feedstock and thus produce a hydrotreated effluent. Said process comprises a step of hydroisomerization, in the presence of hydrogen and a hydroisomerization catalyst, of an effluent from the hydrotreated effluent to obtain a hydroisomerized effluent. The hydroisomerization catalyst used may comprise a group VIII metal chosen from Pt and Pd, alone or in combination and a support which may be amorphous or crystalline chosen from alumina, amorphous alumina silica, ferrierite, 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, MgAPSO-11, MgAPSO-31, MgAPSO-41, MgAPSO-46, ELAPSO-11, ELAPSO-3, EMAPSO-41, ELAPSO-11, ELAPSO-31, ELAPSO-41, alone or in combination.

[0017] In a first embodiment claimed in claim 1, said method comprises a step of separating the hydrotreated effluent and / or the isomerized effluent to obtain a vapor effluent and a liquid effluent; a step of distilling the liquid effluent or the hydroisomerized effluent to produce a kerosene cut and a diesel cut and a step of hydrocracking the diesel cut to obtain a hydrocracked effluent comprising a kerosene cut. Said method therefore allows the co-production of diesel and kerosene cuts which are separated by a distillation step and the diesel cut obtained then undergoes a hydrocracking step. Such a step of hydrocracking the diesel cut is not implemented in the present invention.

[0018] In a second embodiment claimed in claim 16, said process comprises obtaining a diesel cut from the hydroisomerized effluent, said diesel cut is characterized in that the normal paraffin concentration of a given carbon number is at least twice the corresponding normal paraffin concentration in said hydroisomerized effluent. Said diesel cut undergoes a hydrocracking or hydroisomerization step to obtain a hydrocracked effluent comprising a kerosene cut. Unlike the present invention, said process therefore comprises either a hydrocracking step of the obtained diesel cut, or a step of recycling said diesel cut in the hydroisomerization step.

[0019] In a third embodiment claimed in claim 19, said process comprises a step of separating said hydroisomerized effluent into a vapor effluent and a liquid effluent; a step of distilling the liquid effluent or the hydroisomerized effluent to obtain a kerosene cut and a diesel cut, and a step of hydrocracking said diesel cut to obtain a hydrocracked effluent comprising a kerosene cut. Unlike the present invention, said process therefore allows the co-production of diesel and kerosene cuts which are separated by a distillation step and the diesel cut obtained then undergoes a hydrocracking step.

[0020] US patent 8,324,439 B2 teaches a method for treating renewable feedstocks of plant or animal origin. Said method comprises a step of hydrotreating the renewable feedstock, a step of separating the hydrotreated effluent to obtain hydrogen, other gases and at least one effluent containing hydrocarbons. Said process then comprises a step of hydroisomerization of at least a portion of said effluent containing hydrocarbons in the presence of a selective hydroisomerization catalyst, said catalyst comprising at least one one-dimensional zeolite with 10 MR and at least one metal from group VIII and / or group VIB. Finally, said process comprises a step of separation of the hydroisomerized effluent in order to obtain hydrogen, other gas and at least one diesel-type cut. Said patent also teaches a process comprising a step of hydroisomerization of an effluent resulting from the step of hydrotreatment of a renewable feedstock of animal or plant origin on a hydroisomerization catalyst. Said catalyst comprises at least one one-dimensional zeolite with 10 MR of structural code TON or EUO, or a zeolite ZSM-48, ZBM-30, IZM-1, COK-7, EU-2 and EU-11, alone or in a mixture.Structural codes are defined in the International Zeolite Association (IZA) classification: http: / / www.iza-structure.org / databases / ).

[0021] Patent application US 2014 / 0291200 A1 describes a process for producing diesel with a sulfur content of less than 10 ppm from renewable feedstocks, comprising the following steps: a. A hydrotreatment stage of renewable feedstocks b. A step of separating the hydrotreated effluent from a) into a hydrogen-rich gaseous fraction and a liquid hydrocarbon fraction c. A step of eliminating the H2S dissolved in the liquid hydrocarbon effluent from b) d. A step of hydroisomerization of at least a portion of the liquid effluent from step b) on a catalyst comprising at least one metal from group VIII or a combination of a metal from group VIII and a metal from Group VIB on an amorphous support of alumina or silica-alumina type or crystalline, i.e. comprising a 10MR zeolite chosen from zeolites of structural type TON, EU-0 or chosen from zeolites ZSM-48, ZBM-30, IZM-1, COK-7, EU-2 and EU-11 alone or as a mixture, e. A step of separating the resulting effluent into a hydrogen-rich gaseous fraction and at least one diesel fraction

[0022] The recycling of the gaseous fractions from separation steps b) and / or e) in steps a) and / or d) is mentioned with the aim of better control of the exothermicity of the reactions within step a). No recycling of a part of the diesel fraction obtained or of a fraction heavier than the diesel in step a) and / or e) is mentioned.

[0023] Patent application US 2021 / 0395620 A1 describes a process for producing kerosene from renewable feedstocks. The process comprises a first step of hydrotreating the renewable feedstock in dilution with a hydro cut carbonaceous, followed by a hydrocracking step. The hydrocracked effluent is then separated into at least one gaseous fraction and at least one liquid fraction. More specifically, the separation step allows the production of a kerosene-type cut and a heavy diesel-type cut. At least a portion of the hydrocracked effluent, more specifically the kerosene-type cut, is then directed to the hydrodearomatization step in order to make it compatible with current product specifications, in particular the reduction of the aromatic content.

[0024] Patent applications WO 2010 / 000934 A1 and US 2010 / 000908 describe a process for producing kerosene from renewable feedstocks, comprising a first step of hydrodeoxygenation of renewable feedstocks allowing the production of n-paraffins. A second step according to the process allows the hydroisomerization of the n-paraffins from the first step and the production of an effluent rich in iso-paraffins. The latter is sent to a separation and fractionation step allowing the production of a cut boiling in the gasoline range, a cut boiling in the kerosene range and possibly a cut boiling in the diesel range and a cut having a boiling point greater than or equal to 200°C.The fraction having a boiling point greater than or equal to 200°C, optionally mixed with the fraction boiling in the diesel range, is then specifically recycled to a hydroisomerization stage which may be identical to or distinct from the first hydroisomerization stage in order to be re-isomerized therein. The isomerization catalyst(s) comprise a group VIII metal and a support comprising a zeolite chosen from SAPO-11, SAPO-41, ZSM-22, ZSM-23 or ferrierite.

[0025] Patent application US 2014 / 0005450 A1 describes a method for manufacturing synthetic distillates, based on the hydrotreatment of a feedstock then its hydroisomerization / hydrocracking followed by a step of separating the paraffins (n-paraffins and i-paraffins) generated on a molecular sieve. More particularly, the passage on a molecular sieve makes it possible to separate a cut rich in n-paraffins and a cut rich in i-paraffins. The cut rich in i-paraffins is then fractionated by distillation allowing the production of at least one fraction of heavy distillates and at least one fraction of light distillates or diesel. A recycle of the n-paraffins to the hydroisomerization / hydrocracking step is described. A recycle of a portion of the heavy distillates fraction is also described. This is a selective recycle of a stream according to its chemical family and not according to its distillation interval.The hydroisomerization catalyst used may comprise a group VIII metal selected from Pt and Pd, alone or in combination and a support which may be amorphous or crystalline selected from alumina, amorphous silica alumina, ferrierite, 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, MgAPSO-11, MgAPSO-31, MgAPSO-41, MgAPSO-46, ELAPSO-11, ELAPSO-3, EMAPSO-41, ELAPSO-11, ELAPSO-31, ELAPSO-41, laumontite, cancrinite, offretite, stillbite in hydrogen form, mordenite in magnesium or calcium form, and partheite in calcium or magnesium form, alone or in combination.

[0026] US patent application 2017 / 0022424 A1 describes a process for hydrotreating renewable feedstocks for producing an n-paraffinic hydrocarbon fraction. This patent claims a very specific process implementation of the injection of renewable charge into different catalytic beds, mixed with a gas recycle stream (rich in hydrogen) and / or with a liquid recycle stream.The recycled streams (gas and liquid) are obtained from an effluent separation section positioned downstream of the hydrotreatment stage and are injected according to a ratio relative to the renewable feedstock advantageously selected to control the reaction exotherm and the temperature profile of the reactor. A portion of the liquid stream comprising the paraffins is sent to a hydroisomerization step in the presence of a hydroisomerization catalyst comprising at least one metal from group VIII chosen from platinum and palladium, nickel and cobalt and / or at least one metal from group VIB chosen from molybdenum and tungsten and at least one amorphous support of doped alumina, silica alumina type or a zeolitic support preferably comprising a zeolite of structural type TON (NU-10), FER (ferrierite), EUO (EU-1 or ZSM-50) or the zeolites ZSM-48, ZBM-30, IZM-1, COK-7, EU-2 and EU-11 alone or as a mixture.All or part of the hydroisomerized effluent is then sent to a fractionation stage to obtain a gaseous fraction, a naphtha fraction and a middle distillate fraction comprising diesel and kerosene. Part of the middle distillate fraction (150°C+) can be recycled in the hydrotreatment stage or in the hydroisomerization stage. In another variant, part of the 300°C+ fraction can be recycled in the hydroisomerization stage so as to upgrade this cut into lighter products and to increase the cold properties.

[0027] Patent application US 2011 / 0105812 A1 describes a process for improving the cold properties of a diesel cut produced from renewable feedstocks. The process comprises a step of hydrogenation / deoxygenation of the renewable feedstocks allowing the production of an n-paraffinic effluent followed by a step of hydroisomerization and selective hydrocracking of the n-paraffinic effluent. The effluent collected after hydroisomerization and selective hydrocracking is then selectively separated to produce at least one diesel stream comprising a portion of the paraffins having a boiling point in the diesel range, at least one recycled stream comprising another portion of the paraffins having a boiling point in the diesel range (preferably the Ci6+), the composition of the diesel stream and the recycled stream being different, at least one light stream containing at least the LPGs and at least one naphtha-type stream. The recycled stream is advantageously recycled to the hydroisomerization and selective hydrocracking stage. The process is carried out according to a so-called "one-step" configuration, i.e. with a single high-pressure reaction section.The hydroisomerization catalyst used may comprise a group VIII metal selected from Pt and Pd, alone or in combination and a support which may be amorphous or crystalline selected from alumina, amorphous silica alumina, ferrierite, 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, MgAPSO-11, MgAPSO-31, MgAPSO-41, MgAPSO-46, ELAPSO-11, ELAPSO-3, EMAPSO-41, ELAPSO-11, ELAPSO-31, ELAPSO-41, laumontite, cancrinite, offretite, stillbite in hydrogen form, mordenite in magnesium or calcium form, and partheite in calcium or magnesium form, alone or in combination.

[0028] Patent application WO 2021 / 099343 A1 describes the composition of a hydrocarbon fraction rich in iso-paraffins and more specifically the composition of a hydrocarbon fraction having an excellent freezing point, compatible with an aviation fuel application. More particularly, the object of the invention is to provide an aviation fuel type hydrocarbon fraction with increased yield and density and produced from a renewable feedstock. Said composition is obtained by a process comprising the hydrodeoxygenation of a renewable feedstock of vegetable oil type followed by a step of isomerization of the n-paraffins formed to produce iso-paraffins, the isomerization catalyst comprising a group VIII metal chosen from platinum, palladium, and nickel and a support comprising a zeolite chosen from SAPO-11, SAPO-41, ZSM-22, ZSM-23 or ferrierite.The iso-paraffins formed can then be fractionated to obtain said composition.

[0029] Application US2022 / 0403252 describes a process for producing diesel and kerosene comprising the hydrotreatment of renewable feedstocks of the vegetable oil type followed by a step of hydroisomerization of the hydrotreated effluent and then fractionation of the intermediate paraffinic effluent produced by hydroisomerization into diesel and kerosene cuts. No separation step is described between the hydrotreatment and hydroisomerization steps. This is a so-called one-step process implementation, i.e. the hydrotreatment and hydroisomerization can be carried out in a single reactor or in separate reactors without intermediate separation. The hydroisomerization catalysts comprise a group VIII metal and preferably platinum and optionally a support chosen from SAPO-11, SAPO-41, ZSM-22, ZSM-23 zeolites or ferrierite.

[0030] Within the meaning of the present invention, the various embodiments presented can be used alone or in combination with each other, without limitation of combination.

[0031] In the sense of the present invention, the different parameter ranges for a given step such as pressure ranges and temperature ranges may be used alone or in combination. For example, in the sense of the present invention, a preferred range of pressure values ​​may be combined with a more preferred range of temperature values.

[0032] In the remainder of the text, the term naphtha cut or naphtha is understood to mean the hydrocarbon fraction having a boiling point lower than the middle distillate cut. The middle distillate cut generally has an initial cutting point of between 120 and 160°C, preferably 120°C. The naphtha cut can have boiling points between that of hydrocarbon compounds having 5 carbon atoms per molecule (or 36°C boiling point) up to 216°C and includes the gasoline cut.

[0033] Throughout the remainder of the text, the term kerosene or kerosene cut is understood to mean the cut having initial and final boiling points of between 120 and 300°C and the term diesel or gas oil cut is understood to mean a cut having initial and final boiling points of between 120 and 400°C and preferably between 120 and 380°C.

[0034] In the following text, the groups of chemical elements are given according to the CAS classification (CRC Handbook of Chemistry and Physics, publisher CRC press, editor-in-chief DR Lide, 81st edition, 2000-2001). For example, group VIII according to the CAS classification corresponds to the metals of columns 8, 9 and 10 according to the new IUP AC classification, and group VIB to the metals of column 6.

[0035] In the remainder of the text, the expressions "between ... and..." and "between .... and ..." are equivalent and mean that the limit values ​​of the interval are included in the range of values ​​described. If this were not the case and the limit values ​​were not included in the range described, such precision will be provided by the present invention.

[0036] In the present description, the expression "greater than..." is understood as strictly greater than, and symbolized by the sign ">", and the expression "less than" as strictly less than, and symbolized by the sign "<".

[0037] ADVANTAGES OF THE METHOD ACCORDING TO THE INVENTION

[0038] In attempting to develop a method for treating a feedstock from a renewable source, the applicant discovered that the combination of the use of a specific bi-functional catalyst comprising a hydrogenating / dehydrogenating phase based on noble metal (Pt) and a support comprising a specific zeolite chosen from zeolites with structural code MTW, and zeolite IZM-2 alone or in mixture for the hydroconversion stage of linear paraffins from the hydrodeoxygenation stage of renewable feedstocks with the implementation of a fractionation stage of at least part of the hydroconverted liquid effluent, was of great interest. Subject of the invention

[0039] More specifically, the present invention relates to a method for treating a feedstock from a renewable source to simultaneously produce at least one diesel cut and at least one kerosene cut, said method comprising at least the following steps, and preferably consisting of the following steps:

[0040] a) a step of hydrotreating said feedstock in the presence of a fixed-bed catalyst, said catalyst comprising a hydrogenating function and an oxide support, at a temperature of between 200 and 450°C, at a pressure of between 1 and 10 MPa, at an hourly space velocity of between 0.1 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 2000 Nm3 of hydrogen / m3 of feedstock,

[0041] b) a step of separating at least a portion of the effluent from step a) into at least one light gaseous fraction, at least one hydrocarbon liquid effluent, and at least one aqueous liquid effluent,

[0042] c) a step of hydroconversion of at least a portion of the liquid hydrocarbon effluent from step b) in the presence of at least one bifunctional fixed-bed hydroconversion catalyst, said catalyst comprising a hydrogenating phase comprising at least one noble metal from group VIII of the periodic table chosen from platinum and palladium and a support comprising at least one zeolite chosen from zeolites with structural code MTW, and zeolite IZM-2 alone or as a mixture, and at least one binder, said hydroconversion step being carried out at a temperature of between 250 and 500°C, at a pressure of between 1 and 10 MPa, at an hourly space velocity of between 0.1 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 1000 NmVm3 of feedstock,

[0043] d) a step of separating at least part of the effluent from step c) which makes it possible to separate at least one gaseous fraction, and at least one hydrocarbon liquid effluent,

[0044] e) a step of fractionating the liquid hydrocarbon effluent from step d) into at least one kerosene cut and at least one diesel cut,

[0045] no recycling step in step a) of hydrotreatment and / or step c) of hydroconversion, of all or part of the effluents from step c) of hydroconversion, of the effluents from step d) of separation and / or of the effluents from step e) of fractionation being implemented.

[0046] An advantage of the present invention is to provide a method for treating a feedstock from a renewable source in two stages to produce diesel and kerosene, using a specific catalyst in the hydroconversion stage making it possible to obtain a gain in activity and selectivity. The use of the specific catalyst makes it possible, all other things being equal, to reduce the temperature necessary to obtain the cold property targets on the co-produced kerosene and diesel cuts. The implementation of the hydroconversion stage with the specific catalyst according to the invention also makes it possible, for the cold property targets targeted, to maximize the yields of the kerosene and diesel cuts of interest co-produced in said method.

[0047] Another advantage of the present invention lies in the use of a specific catalyst in the hydroconversion step combined with the implementation of a step of fractionation of the hydroconversion effluent, which makes it possible both to maximize the yield of the sum of the kerosene and diesel cuts obtained and to upgrade said cuts by adjusting the cutting point between the kerosene cut and the diesel cut by the fractionation step, allowing the production of these two cuts to the required specifications.

[0048] Another advantage of the present invention is to provide a flexible process for treating a feedstock from a renewable source in two stages to produce diesel and kerosene comprising a stage of fractionation of the hydroconversion effluent which makes it possible to adjust the distillation intervals of the desired kerosene and diesel cuts and to adjust their cut point and in particular the final boiling point of the kerosene cut.

[0049] Another advantage of the present invention is to provide a method for treating a feedstock from a renewable source in two stages to produce diesel and kerosene comprising a step of fractionation of the hydroconversion effluent which allows, optionally, the tailing of the diesel fraction, i.e. the elimination of heavy compounds having a boiling point above 350°C, preferably above 370°C. Such a configuration makes it possible to treat heavier renewable source feedstocks in said method and to jointly produce kerosene and diesel cuts with cold property targets with this type of heavier feedstock.

[0050] Another advantage of the present invention is to provide a method for treating a feedstock from a renewable source which undergoes hydrotreatment before being sent to a hydroconversion step using a specific bifunctional catalyst also making it possible to improve the overall yield of the co-produced diesel and kerosene cuts for targeted cold property values ​​(measured for example by filterability limit temperature values ​​or crystal disappearance point). Detailed description of the invention Charges

[0051] The present invention is particularly dedicated to the preparation of diesel and / or kerosene fuel bases corresponding to new environmental standards, from charges from renewable sources.

[0052] The feedstocks from renewable sources used in the process according to the present invention are advantageously chosen from vegetable oils (for example palm, rapeseed, soybean), animal fats, used cooking oils, oils of microbial origin (for example from algae), fish oils, long paraffins (waxes) from the Fischer-Tropsch process, crude or having undergone prior treatment, or mixtures of such feedstocks, containing triglycerides and / or free fatty acids and / or esters. The vegetable oils may advantageously be crude or refined, totally or in part, and derived from the following plants: rapeseed, sunflower, soybean, palm, palm kernel, olive, coconut, jatropha, this list not being limiting. Algal or fish oils are also relevant.Animal fats are advantageously chosen from lard or fats composed of residues from the food industry or from the catering industry.

[0053] These fillers essentially contain chemical structures of the triglyceride type that the skilled person also knows under the name fatty acid triester as well as free fatty acids. A fatty acid triester is thus composed of three fatty acid chains. These fatty acid chains in the form of triester or in the form of free fatty acids, 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, in particular for oils derived from algae which generally have a number of unsaturations per chain of 5 to 6.

[0054] The molecules present in the fillers 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 fillers, the level of unsaturation, expressed as the number of unsaturations per hydrocarbon fatty chain, is advantageously between 0 and 6.

[0055] Feedstocks from renewable sources generally also contain various impurities, including heteroatoms such as nitrogen. Nitrogen contents in vegetable oils are generally between approximately 1 ppm and 1000 ppm by weight, depending on their nature. Process and catalysts

[0056] Advantageously, the load can undergo prior to step a) of the method according to the invention a pre-treatment or pre-refining step so as to eliminate, by appropriate treatment, contaminants such as metals, such as alkaline compounds for example on ion exchange resins, alkaline earths and phosphorus. Suitable treatments may for example be thermal and / or chemical treatments well known to those skilled in the art.

[0057] In accordance with step a) of the process according to the invention, the feedstock, optionally pretreated, is brought into contact with a fixed-bed catalyst at a temperature of between 200 and 450°C, preferably between 220 and 350°C, preferably between 220 and 320°C, and even more preferably between 220 and 310°C. The pressure is between 1 and 10 MPa, preferably between 1 and 6 MPa and even more preferably between 1 and 4 MPa. The hourly space velocity, i.e. the volume of feedstock per volume of catalyst per hour, is between 0.1 and 10 h1. The feedstock is brought into contact with the catalyst in the presence of hydrogen. The total quantity of hydrogen mixed with the feedstock is such that the hydrogen / feedstock ratio is between 70 and 2000 Nm3 of hydrogen / m3 of feedstock and preferably between 150 and 1000 Nm3 of hydrogen / m3 of feedstock.

[0058] In step a) of the process according to the invention, the fixed-bed catalyst is advantageously a hydrotreatment catalyst comprising a hydro-dehydrogenating function comprising at least one metal from group VIII and / or group VIB, taken alone or as a mixture and a support chosen from the group formed by alumina, silica, silica-aluminas, magnesia, clays and mixtures of at least two of these minerals. This support may also advantageously contain other compounds and for example oxides chosen from the group formed by boron oxide, zirconia, titanium oxide, phosphoric anhydride. The preferred support is an alumina support and very preferably alumina q, 6 or y.

[0059] Said catalyst is advantageously a catalyst comprising metals from group VIII, preferably chosen from nickel and cobalt, taken alone or as a mixture, preferably in association with at least one metal from group VIB, preferably chosen from molybdenum and tungsten, taken alone or as a mixture.

[0060] The content of metal oxides from groups VIII and preferably nickel oxide is advantageously between 0.5 and 10% by weight of nickel oxide (NiO) and preferably between 1 and 5% by weight of nickel oxide and the content of metal oxides from groups VIB and preferably molybdenum trioxide is advantageously between 1 and 30% by weight of molybdenum trioxide (MoO3), preferably from 5 to 25% by weight, the percentages being expressed in % by weight relative to the total mass of the catalyst.

[0061] The total content of metal oxides from groups VIB and VIII in the catalyst used in step a) is advantageously between 5 and 40% by weight and preferably between 6 and 30% by weight relative to the total mass of the catalyst.

[0062] Said catalyst used in step a) of the process according to the invention must advantageously be characterized by a high hydrogenating power so as to orient the selectivity of the reaction as much as possible towards a hydrogenation conserving the number of carbon atoms of the fatty chains, i.e. the hydrodeoxygenation route, in order to maximize the yield of hydrocarbons entering the distillation field of kerosenes and / or diesels. This is why, preferably, the operation is carried out at a relatively low temperature. Maximizing the hydrogenating function also makes it possible to limit the polymerization and / or condensation reactions leading to the formation of coke which would degrade the stability of the catalytic performances. Preferably, a Ni or NiMo type catalyst is used.

[0063] Said catalyst used in hydrotreatment step a) of the process according to the invention may also advantageously contain a doping element chosen from phosphorus and boron, taken alone or as a mixture. Said doping element may be introduced into the matrix or preferably be deposited on the support. Silicon may also be deposited on the support, alone or with phosphorus and / or boron and / or fluorine.

[0064] The weight content of oxide of said doping element is advantageously less than 20% by weight and preferably less than 10% by weight and it is advantageously at least 0.001% by weight.

[0065] Preferred catalysts are the catalysts described in patent application FR 2 943 071 describing catalysts having high selectivity for hydrodeoxygenation reactions.

[0066] Other preferred catalysts are the catalysts described in patent application EP 2 210 663 describing supported or bulk catalysts comprising an active phase consisting of a sulfurized element from group VIB, the element from group VIB being molybdenum.

[0067] The metals of the catalysts used in step a) of hydrotreatment of the process according to the invention are sulphide metals or metallic phases and preferably sulphide metals.

[0068] It would not be outside the scope of the present invention to use in step a) of the process according to the invention, simultaneously or successively, a single catalyst or several different catalysts. This step can be carried out industrially in one or more reactors with one or more catalytic beds and preferably with a descending liquid flow.

[0069] Said hydrotreatment step a) allows the hydrogenation, hydrodeoxygenation, hydrodenitrogenation and hydrodesulfurization of said feedstock.

[0070] In accordance with step b) of the process according to the invention, a step of separating at least at least a portion and preferably all of the effluent from step a) is used. Said step b) makes it possible to separate at least one so-called light gaseous fraction rich in hydrogen, at least one liquid hydrocarbon effluent consisting of n-paraffins, and at least one aqueous liquid effluent.

[0071] Said light gaseous fraction comprises at least the hydrogen not converted by the reactions carried out in step a), at least the gases with one or more oxygen atoms resulting from the decomposition of the oxygenated compounds in step a) and at least the C4 compounds, i.e. the compounds C1 to C4 preferably having a final boiling point of less than 20°C. The aim of this step is to separate the gases from the liquids. More particularly, the aim is to recover at least the hydrogen-rich gases which may also contain compounds such as CO and CO2> at least one liquid hydrocarbon effluent consisting of n-paraffins and at least one aqueous liquid effluent containing the water produced by the reactions carried out in step a). Said liquid hydrocarbon effluent preferably has a sulfur content of less than 10 ppm by weight, a nitrogen content of less than 2 ppm by weight.

[0072] Separation step b) can advantageously be implemented by any method known to those skilled in the art, such as, for example, the combination of one or more high and / or low pressure separators operated hot or cold, and / or distillation steps, and / or high pressure and / or low pressure stripping.

[0073] Step b) also allows the separation of at least one aqueous liquid effluent, preferably water. The removal of at least a portion of the water and preferably all of the water can be carried out by any methods and techniques known to those skilled in the art. Preferably, the removal of the water is carried out by decantation in a separator drum or by drying or by passing over a desiccant or by flash or by a combination of at least two of these techniques. The atomic oxygen content of the liquid hydrocarbon effluent containing the paraffinic hydrocarbons from step b) of the process according to the invention, expressed in parts per million by weight (ppm), is preferably less than 10,000 ppm, preferably less than 6,000 ppm, very preferably less than 1,000 ppm by weight, even more preferably less than 500 ppm by weight.The content in ppm by weight of atomic oxygen in said hydrocarbon liquid effluent is measured by the infrared absorption technique such as for example the technique described in patent application US2009 / 0018374A1.

[0074] In accordance with step c) of the process according to the invention, at least part and preferably all of the liquid hydrocarbon effluent from step b) of the process according to the invention is converted in the presence of at least one fixed-bed bifunctional hydroconversion catalyst, said catalyst comprising a hydrogenating phase comprising at least one noble metal from group VIII of the periodic table chosen from platinum and palladium alone or as a mixture and a support comprising at least one zeolite chosen from zeolites with structural code MTW and IZM-2 alone or as a mixture and at least one binder, said hydroconversion step being carried out at a temperature of between 250 and 500°C, at a pressure of between 1 and 10 MPa, at an hourly space velocity of 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 1000 NmVm3 of feed, and preferably between 150 and 750 Nm3 / m3 of feed.

[0075] The operating conditions of hydroconversion step c) are adjusted to promote the hydroisomerization or hydrocracking reactions as required. Preferably, the hydroconversion step c) of the process according to the invention is a hydroisomerization step and advantageously operates at a temperature of between 250 and 450°C, and very preferably, between 250 and 400°C, at a pressure of between 2 and 10 MPa and very preferably, between 3 and 9 MPa, at an hourly volumetric velocity advantageously of between 0.2 and 7 h 1 and very preferably, between 0.5 and 5 h1, at a hydrogen flow rate such that the hydrogen / feed volume ratio is advantageously of between 100 and 1000 Nm3 / m3 of feed and preferably between 150 and 1000 Nm3 / m3 of feed.

[0076] Advantageously, the operating conditions implemented in hydroconversion step c) can advantageously be adjusted to satisfy the requirements in terms of cold properties of the two cuts co-produced simultaneously, a diesel or bio-diesel cut and a kerosene or bio-kerosene cut. Generally the total pressures are fixed, and the adjustment of the operating conditions is usually carried out by a variation of the temperature of the hydroconversion step and / or the hourly volumetric flow rate.

[0077] According to the invention, the catalyst used in step c) is a bifunctional catalyst comprising a hydrogenating phase comprising at least one noble metal from group VIII of the periodic table chosen from platinum and palladium alone or as a mixture and a support comprising at least one zeolite chosen from zeolites of structural type MTW, and zeolite IZM-2 alone or as a mixture and at least one binder.

[0078] The hydro / dehydrogenating function

[0079] Preferably the group VIII metal of the catalyst used in step c) is platinum.

[0080] Advantageously, the hydro / dehydrogenating (metallic) element and preferably platinum can be introduced onto the catalyst support by any method known to those skilled in the art, such as for example co-mixing, dry impregnation, exchange impregnation.

[0081] According to one or more embodiments, the content of group VIII metal, and preferably the platinum content in the catalyst used in step c) is between 0.01 and 4% by weight, preferably between 0.05% and 2% by weight, relative to the total weight of said catalyst.

[0082] The catalyst used in step c) may also advantageously further comprise at least one additional metal chosen from the group formed by the metals of groups IIIA, IVA and VIIB of the periodic table of elements and preferably chosen from gallium, indium, tin and rhenium. Said additional metal is preferably chosen from indium, tin and rhenium.

[0083] Preferably, the content of at least one additional metal in the catalyst used in step c) is between 0.01 and 2% by weight, preferably between 0.05 and 1% by weight, relative to the total weight of said catalyst.

[0084] According to one embodiment, the sulfur content in the hydroconversion catalyst is such that the ratio of the number of moles of sulfur to the number of moles of the at least one metal from group VIIIB is between 0.3 and 3. According to one or more embodiments, the presence of sulfur in the catalyst comes from an optional sulfurization step of the hydroconversion catalyst. According to one or more embodiments, the presence of sulfur in the catalyst comes from potentially present impurities, such as for example in the alumina binder. According to another embodiment, the catalyst does not contain sulfur.

[0085] The acid function.

[0086] According to the invention, the catalyst used in step c) comprises a support comprising at least one zeolite chosen from zeolites of MTW structural type, and IZM-2 zeolite alone or as a mixture and at least one binder.

[0087] The acid function of the bifunctional catalyst used in step c) is provided by the zeolite chosen from zeolites of MTW structural type, and IZM-2 zeolite, alone or as a mixture.

[0088] Preferably, the MTW structural type zeolites are chosen from the ZSM-12, TPZ-12, Theta-3, NU-13, CZH-5 zeolites, alone or as a mixture and preferably, the MTW structural type zeolite is ZSM-12.

[0089] According to a preferred embodiment, the catalyst used in step c) comprises a support comprising an IZM-2 zeolite alone or a support comprising a ZSM-12 zeolite alone.

[0090] Zeolite IZM-2 is a crystallized microporous solid whose crystal structure and preparation process are described in patent application FR2918050A1. The structural code of zeolite IZM-2 is not known to date. Zeolite ZSM-12 is a crystallized microporous solid whose crystal structure is described on the website of the International Zeolyst Association (http: / / www.iza-structure.org / ). It is a one-dimensional zeolite with 12 MR, its structural code is MTW. A preparation process The preparation of this zeolite is for example described in the article Synthesis of zeolite ZSM-12 in the System (MTEA^O-lS^O-SiCVA^Os-f^O by S. Ersnt et al. (Zeolites, 7, 5, 458-462, DOI10.1016 / 0144-2449(87)90015-7).

[0091] The zeolites are preferably essentially in acid form, that is to say that the atomic ratio between the monovalent compensation cation (for example sodium) and the aluminum inserted in the crystal lattice of the solid is advantageously less than 0.1, preferably less than 0.05 and very preferably less than 0.01. According to one or more embodiments, the zeolites entering into the composition of said hydroisomerization catalyst are advantageously calcined. According to one or more embodiments, said zeolites are exchanged by at least one treatment with a solution of at least one ammonium salt so as to obtain the ammonium form of the zeolites which, once calcined, leads to the acid form of said zeolites.

[0092] In a preferred embodiment, the catalyst used in step c) comprises a hydrogenating phase comprising platinum and a support comprising an IZM-2 zeolite alone and an alumina binder.

[0093] In another preferred embodiment, the catalyst used in step c) comprises a hydrogenating phase comprising platinum and a support comprising a ZSM-12 zeolite alone and an alumina binder.

[0094] Preferably, the catalyst used in step c) comprises a zeolite content of between 1% and 90% by weight, preferably between 3% and 80% by weight, and more preferably between 4% and 60% by weight, preferably between 4 and 30% by weight and more preferably between 4 and 20% by weight relative to the total weight of said catalyst.

[0095] The binder

[0096] Preferably, the binder of the catalyst support of step c) is amorphous or crystallized. Preferably, the binder used in the catalyst support of step c) is advantageously chosen from the group formed by alumina, silica, silica-alumina, clays, titanium oxide, boron oxide, zirconia and aluminates, taken alone or as a mixture. Preferably, the binder is alumina. Preferably, said binder may contain alumina in all its forms known to those skilled in the art, such as for example alpha, gamma, eta, delta type aluminas.

[0097] Preferably, the catalyst used in step c) comprises a binder content of between 10 and 99% by weight, relative to the total weight of said catalyst, i.e., so as to ensure the addition to 100% by weight of the elements constituting the catalyst used in step c).

[0098] According to the invention, the catalyst support comprises the zeolite mixed with a binder. The shaping of the support in the form of a mixture is carried out in a manner preferred by co-mixing, extrusion then heat treatment of the zeolite with the binder or a precursor of the binder, such as for example boehmite, which by heat treatment transforms into alumina.

[0099] A preferred catalyst of step c) comprises and is preferably constituted by platinum, and a support comprising and preferably constituted by a ZSM-12 zeolite and an alumina binder.

[0100] Another preferred catalyst of step c) comprises and is preferably constituted by platinum, and a support comprising and preferably constituted by an IZM-2 zeolite and an alumina binder.

[0101] According to a preferred embodiment, the catalyst used in step c) more particularly comprises, and preferably consists of:

[0102] - from 1 to 90% by weight, preferably from 3 to 80% by weight and even more preferred from 4 to 60% by weight of zeolite;

[0103] - from 0.01 to 4% by weight, preferably from 0.05 to 2% by weight of at least one metal of the group VIIIB, preferably platinum;

[0104] - optionally from 0.01 to 2% by weight, preferably from 0.05 to 1% by weight of at least minus one additional metal selected from the group formed by the metals of groups IIIA, IVA and VIIB; - optionally a sulfur content, preferably such that the ratio of the number of moles of sulfur to the number of moles of group VIIIB metal(s) is between 0.3 and 3; and - optionally at least one binder, preferably alumina, ensuring the addition to 100% by weight in the catalyst, relative to the total weight of the catalyst from step c).

[0105] Preferably, the catalyst used in step c) is shaped in the form of cylindrical or polylobed extrudates such as bilobed, trilobed, polylobed of straight or twisted shape. According to one or more embodiments, the catalyst used in step c) is shaped in the form of crushed powders, tablets, rings, balls, wheels. Techniques other than extrusion, such as pelletizing or coating, can advantageously be used.

[0106] Preferably, the noble metal contained in said catalyst used in step c) can advantageously be reduced. One of the preferred methods for carrying out the reduction of the metal is treatment at a temperature between 150 and 650°C and a total pressure between 0.1 and 25 MPa. For example, a reduction can comprise a two-hour stage at 150°C followed by a temperature increase to 450°C at a rate of 1°C / min followed by a two-hour stage at 450°C; during the reduction step, the hydrogen flow rate can be 1000 normal m3 hydrogen / m 3 catalyst and the total pressure can be kept constant at 0.1 MPa. Any The reduction method can advantageously be considered either in situ (the reduction of the catalyst is carried out in the same unit where the catalytic reaction is carried out), or ex situ (the reduction is carried out outside the unit where the catalytic reaction is carried out, before loading the catalyst into the unit).

[0107] According to the invention, the process comprises a step d) of separating at least part and preferably all of the effluent from step c).

[0108] Said step d) makes it possible to separate at least one so-called light gaseous fraction and at least one hydrocarbon liquid effluent. Optionally, step d) also makes it possible to separate at least a portion of the residual water and preferably all of the residual water.

[0109] Said so-called light gaseous fraction comprises at least the hydrogen not converted by the reactions described in step c) and at least a portion of the C4 cracking products, i.e. C1 to C4 compounds preferably having a final boiling point below 20°C. The aim of this step is to separate the gases from the liquids. More particularly, the aim is to recover at least the hydrogen-rich gases, at least one liquid hydrocarbon effluent rich in branched paraffins and optionally an aqueous liquid effluent containing a small amount of residual water (residual water generated either by the hydrodeoxygenation of the residual oxygenated compounds present in the feedstock of step c) or by a slight entrainment of water from step b) to step c)).

[0110] The separation step d) described can advantageously be implemented by any method known to those skilled in the art such as, for example, the combination of one or more high and / or low pressure separator flasks operated hot or cold, and / or distillation steps, and / or high pressure and / or low pressure stripping.

[0111] According to the invention, the process comprises a step e) of fractionating the hydrocarbon effluent from step d) into at least one kerosene cut and at least one diesel cut.

[0112] Advantageously, said fractionation step also allows the separation of at least one gas cut consisting mainly of light hydrocarbons in CrC4, and at least one lighter hydrocarbon cut called naphtha.

[0113] More particularly, said fractionation step e) advantageously makes it possible to adjust the cutting point between the kerosene and naphtha cuts in the temperature range between 80 and 160°C, preferably in the temperature range between 100 and 140°C and preferably around 120°C.

[0114] More particularly, said fractionation step e) advantageously makes it possible to adjust the cutting point between the kerosene and diesel cuts in the temperature range between 250 and 300°C, preferably in the temperature range between 260 and 290°C and preferably around 280°C.

[0115] The implementation of said fractionation step e) has the advantage of making the process according to the invention flexible in that it makes it possible to adjust the distillation intervals of the desired kerosene and diesel cuts and to adjust their cutting point and in particular the final boiling point of the kerosene cut.

[0116] Optionally, the fractionation step e) can also allow the tailing of the diesel cut, i.e. it allows the elimination of compounds having a boiling point greater than 350°C, preferably greater than 370°C.

[0117] In this embodiment, at least one heavy cut having a boiling temperature greater than 350°C, preferably greater than 370°C, is advantageously separated in said fractionation step e).

[0118] In this case, said heavy cut is not recycled either in the hydrotreatment step a) or in the hydroconversion step c) in accordance with the invention.

[0119] For the purpose of producing kerosene and diesel cuts, the indicated cut points can advantageously be adapted either to maximize the yields of one cut compared to another, or to provide flexibility to the process and allow the treatment of charges consisting of heavier compounds, or to adjust the properties of the cuts to the required specifications.

[0120] Fractionation step e) can be carried out by any method known to those skilled in the art and is advantageously carried out in a distillation column or in a steam stripping step followed by a distillation column.

[0121] The recovery of the bio-naphtha cut is not the subject of the present invention, but this cut can advantageously be sent to a steam cracking or reforming unit or even recovered as a gasoline base in a mixture with other gasoline bases.

[0122] The process according to the invention advantageously does not include a hydrocracking step downstream of step c) of hydroconversion of part or all of the effluent from step c).

[0123] According to the invention, the process according to the invention does not include recycling in step a) of hydrotreatment and / or step c) of hydroconversion, of all or part of the effluents from step c) of hydroconversion, of the effluents from step d) of separation and of the effluents from step e) of fractionation. Description of the figures

[0124] [Fig-1] [Fig.l] represents the different stages of the production process of kerosene and renewable diesel in two stages, using a specific catalyst in hydroconversion stage c) and including a fractionation stage e) of the hydroconverted effluent.

[0125] The feedstock from renewable sources is sent via line 1 mixed with make-up and / or recycled hydrogen (line 2) to a hydrotreatment step a) (allowing hydrogenation, hydrodeoxygenation, hydrodenitrogenation and hydrodesulfurization of the feedstock). The hydrotreated effluent from hydrotreatment step a) is withdrawn via line 3 and is sent to three-phase separation step b) which makes it possible to separate at least one hydrogen-rich gaseous effluent (line 4), and at least one hydrocarbon liquid effluent (line 5). Step b) also makes it possible to eliminate at least a portion of the water produced by the hydrodeoxygenation reactions and preferably all of this water (line 6).

[0126] The liquid hydrocarbon effluent (5) is sent to a hydroconversion step c) (hydroisomerization and / or hydrocracking), in the presence of a make-up and / or recycled hydrogen stream (line 7) to produce an effluent (line 8) which is sent to a three-phase separation step d) making it possible to separate a hydrogen-rich gaseous effluent (9) which may also contain light products such as the C1 - C4 cut, and at least one liquid hydrocarbon effluent (10). Said step also makes it possible to eliminate at least part of the water and preferably all of the residual water (11).

[0127] The liquid hydrocarbon effluent from step d) (10) is sent to a distillation fractionation step e) allowing the separation of a light gaseous fraction (12), a naphtha hydrocarbon cut (13), and the co-production of a kerosene cut (14), and a diesel cut (15). Optionally, a heavy cut (16) can also be separated in the fractionation step e). No recycling step for the effluents from steps c), d) and e) is implemented.

[0128] The examples below illustrate the invention without limiting its scope. EXAMPLES

[0129] Example 1: preparation of a hydrotreatment catalyst (Cl).

[0130] The catalyst is an industrial catalyst based on nickel, molybdenum and phosphorus on alumina with molybdenum oxide MoO3 contents of 22% by weight, nickel oxide NiO of 4% by weight and phosphorus oxide P2O5 of 5% by weight relative to the total weight of the finished catalyst.

[0131] Example 2: Preparation of a hydroconversion catalyst not in accordance with the invention (C2).

[0132] The silica-alumina powder is prepared according to the synthesis protocol described in patent EPI 415 712A. The quantities of orthosilicic acid and aluminum hydrate are chosen so as to have a composition of 70% by weight of alumina A12O3 and 30% by weight of silica SiO2 in the final solid.

[0133] This mixture is rapidly homogenized in a commercial colloidal mill in the presence of nitric acid so that the nitric acid content of the suspension in mill output is 8% by weight of the mixed silica-alumina solid. Then the suspension is dried conventionally in an atomizer in a conventional manner from 300°C to 60°C. The powder thus prepared is shaped in a Z arm in the presence of 8% nitric acid relative to the anhydrous product. Extrusion is carried out by passing the paste through a die equipped with orifices of diameter 1.4 mm. The extrudates thus obtained are dried in an oven at 140°C then calcined under a flow of dry air at 550°C then calcined at 850°C in the presence of water vapor.

[0134] The characteristics of the support thus prepared are as follows:

[0135] - an average mesopore diameter measured by mercury porosimetry of 7.7 nm,

[0136] - a total pore volume measured by mercury porosimetry of 0.49 ml / g,

[0137] - a mesoporous volume measured by mercury porosimetry of 0.48 ml / g,

[0138] - a volume of macropores, the diameter of which is greater than 50 nm less than 0.02 ml / g,

[0139] - a BET surface area of ​​240 m2 / g.

[0140] 50 grams of silica-alumina extrudates are then subjected to a step dry impregnation with an aqueous solution of platinum tetramine nitrate, left to mature in a water maturer for 24 hours at room temperature and then calcined for two hours in dry air in a crossed bed at 450°C (temperature rise ramp of 5°C / min). The platinum content by weight of the finished catalyst after calcination is 0.57%, its dispersion measured by H2 / O2 titration is 26%, its distribution coefficient measured by Castaing microprobe is 0.87.

[0141] Example 3: Preparation of a hydroconversion catalyst in accordance with the invention (C3). Synthesis of IZM-2 zeolite.

[0142] The IZM-2 zeolite was synthesized in accordance with the teaching of patent FR 2 918 050 B. A colloidal suspension of silica known under the commercial term Ludox HS-40 marketed by Aldrich, is incorporated into a solution composed of sodium hydroxide (Prolabo), structuring agent 1,6bis(methylpiperidinium)hexane dibromide, aluminum hydroxide (Aldrich) and deionized water. The molar composition of the mixture is as follows: 1 SiO2; 0.0060 Al2O3; 0.1666 Na2O; 0.1666 l,6bis(methylpiperidinium)hexane; 33.3333 H2O. The mixture is stirred vigorously for half an hour. The mixture is then transferred, after homogenization, into a PARR type autoclave. The autoclave is heated for 5 days at 170°C with stirring on a rotating spit (30 rpm). The product obtained is filtered, washed with deionized water to reach a neutral pH and then dried overnight at 100°C in an oven. The solid is then introduced into a muffle furnace to be calcined to remove the structuring agent.The calcination cycle includes a temperature rise to 200°C, a two-hour hold at this temperature, and a temperature rise. up to 550°C followed by an eight-hour hold at this temperature and finally a return to room temperature. The temperature increases are carried out with a ramp of 2°C / min. The solid thus obtained is then refluxed for 2 hours in an aqueous solution of ammonium nitrate (10 ml of solution per gram of solid, ammonium nitrate concentration of 3 M) in order to exchange the sodium alkali cations with ammonium ions. This refluxing step is carried out four times with a fresh solution of ammonium nitrate, then the solid is filtered, washed with deionized water and dried in an oven overnight at 100°C. Finally, to obtain the zeolite in its acid form (protonated H+), a calcination step is carried out at 550°C for ten hours (temperature increase ramp of 2°C / min) in a crossed bed under dry air (2 normal liters per hour and per gram of solid).The solid thus obtained was analyzed by X-ray diffraction and identified as consisting of IZM-2 zeolite. Characterizations using 27Al isotope NMR, X-ray fluorescence and ICP methods provide the following results for IZM-2: .

[0143] - weight percentage of hexacoordinated aluminum atoms A1VI: 5%,

[0144] - ratio of the number of moles of silicon divided by the number of moles of aluminum network, in mole / mole, Si / Al: 72,

[0145] - ratio of the number of moles of sodium divided by the number of moles of aluminum network, in mole / mole, Na / Al: 0.03. Preparation of IZM-2 / alumina support.

[0146] The IZM-2 / alumina support is obtained by kneading and extruding the IZM-2 zeolite with a Pural SB3 type alumina gel. The kneaded paste is extruded through a 1.8 mm diameter four-lobe die. After drying in an oven overnight at 110°C, the extrudates are calcined at 500°C for two hours (temperature rise ramp of 5°C / min) in a crossed bed under dry air (2 normal liters per hour and per gram of solid). The weight content of the IZM-2 zeolite in the support after calcination is 13% by weight.

[0147] Impregnation of platinum on the IZM-2 / alumina support.

[0148] The platinum impregnation is carried out by dry impregnation of the support with an aqueous solution containing platinum tetramine nitrate Pt(NH3)4(NO3)2. 50 grams of support are used and dry impregnated in a drageoir. After impregnation, the solid is left to mature for at least five hours in laboratory air and then left to dry overnight in an oven at 110°C. Finally, a calcination step is carried out under a flow of dry air (2 normal liters per hour and per gram of solid) in a tubular furnace under the following conditions:

[0149] - increase in temperature from ambient to 450°C at 5°C / min;

[0150] - two-hour stage at 450°C;

[0151] - descent to ambient.

[0152] The Pt content measured by FX on the calcined C3 catalyst is 0.29% by weight, its dispersion measured by H2 / O2 titration is 52%, its distribution coefficient measured by Castaing microprobe is 0.91.

[0153] Example 4: Preparation of a hydroconversion catalyst in accordance with the invention (C4). Zeolite ZSM-12.

[0154] The ZSM-12 zeolite is supplied by the company Zeolyst. The solid was analyzed by X-ray diffraction and identified as consisting of ZSM-12 zeolite. Characterizations using the NMR methods of the isotope 27Al, X-ray fluorescence and ICP provide the following results for ZSM-12:

[0155] - weight percentage of hexacoordinated aluminum atoms A1VI: 0%;

[0156] - ratio of the number of moles of silicon divided by the number of moles of aluminum network, in mole / mole, Si / Al: 43;

[0157] - ratio of the number of moles of sodium divided by the number of moles of aluminum network, in mole / mole, Na / Al: 0.009. Preparation of ZSM-12 / alumina support.

[0158] The ZSM-12 / alumina support is obtained by kneading and extruding the ZSM-12 zeolite with a Pural SB3 type alumina gel. The kneaded paste is extruded through a 1.8 mm diameter four-lobe die. After drying in an oven overnight at 110°C, the extrudates are calcined at 500°C for two hours (temperature rise ramp of 5°C / min) in a traversed bed under dry air (2 normal liters per hour and per gram of solid). The weight content of the ZSM-12 zeolite in the support after calcination is 6% by weight.

[0159] Impregnation of platinum on the ZSM-12 / alumina support.

[0160] The platinum impregnation is carried out by dry impregnation of the support with an aqueous solution containing platinum tetramine nitrate Pt(NH3)4(NO3)2. 50 grams of support are used and dry impregnated in a drageoir. After impregnation, the solid is left to mature for at least five hours in laboratory air and then left to dry overnight in an oven at 110°C. Finally, a calcination step is carried out under a flow of dry air (2 normal liters per hour and per gram of solid) in a tubular furnace under the following conditions:

[0161] - increase in temperature from ambient to 450°C at 5°C / min;

[0162] - two-hour stage at 450°C;

[0163] - descent to ambient.

[0164] The Pt content measured by FX on the calcined C4 catalyst is 0.31% by weight, its dispersion measured by H2 / O2 titration is 38%, its distribution coefficient measured by Castaing microprobe is 0.87.

[0165] Example 5: Preparation of a hydroconversion catalyst not in accordance with the invention (C5). Zeolite ZSM-23.

[0166] The ZSM-23 zeolite is supplied by the company Zeolyst. The solid was analyzed by X-ray diffraction and identified as consisting of ZSM-23 zeolite. Characterizations using the NMR methods of the isotope 27Al, X-ray fluorescence and ICP provide the following results for ZSM-23:

[0167] - weight percentage of hexacoordinated aluminum atoms A1VI: 0%;

[0168] - ratio of the number of moles of silicon divided by the number of moles of aluminum network, in mole / mole, Si / Al: 24;

[0169] - ratio of the number of moles of sodium divided by the number of moles of aluminum network, in mole / mole, Na / Al: 0.002. Preparation of ZSM-23 / alumina support.

[0170] The ZSM-23 / alumina support is obtained by kneading and extruding the ZSM-23 zeolite with a Pural SB3 type alumina gel. The kneaded paste is extruded through a 1.8 mm diameter four-lobe die. After drying in an oven overnight at 110°C, the extrudates are calcined at 500°C for two hours (temperature rise ramp of 5°C / min) in a crossed bed under dry air (2 normal liters per hour and per gram of solid). The weight content of the ZSM-23 zeolite in the support after calcination is 9% by weight.

[0171] Impregnation of platinum on the ZSM-23 / alumina support.

[0172] The platinum impregnation is carried out by dry impregnation of the support with an aqueous solution containing platinum tetramine nitrate Pt(NH3)4(NO3)2. 50 grams of support are used and dry impregnated in a drageoir. After impregnation, the solid is left to mature for at least five hours in laboratory air and then left to dry overnight in an oven at 110°C. Finally, a calcination step is carried out under a flow of dry air (2 normal liters per hour and per gram of solid) in a tubular furnace under the following conditions:

[0173] - temperature rise from ambient to 450°C at 5°C / min;

[0174] - two-hour stage at 450°C;

[0175] - descent to ambient.

[0176] The Pt content measured by FX on the calcined C5 catalyst is 0.32% by weight, its dispersion measured by H2 / O2 titration is 60%, its distribution coefficient measured by Castaing microprobe is 0.94.

[0177] Example 6: hydrotreatment of a feedstock from a renewable source according to a process in accordance with the invention

[0178] In a temperature-regulated reactor so as to ensure operation In an isothermal and fixed-bed feedstock loaded with 190 ml of hydrotreatment catalyst Cl, the catalyst being previously sulfurized, the hydrotreatment of pre-refined rapeseed oil with a density of 920 kg / m3 and an oxygen content of 11% by weight is carried out. The cetane index is 35 and the fatty acid distribution of the rapeseed oil is detailed in Table 1. Prior to the hydrotreatment stage, said feedstock is supplemented with dimethyl disulfide in order to adjust its sulfur content to 50 ppm by weight.

[0179] [Tableauxl] Fatty acid composition (%) 14:0 0.1 16:0 5.0 16:1 0.3 17:0 0.1 17:1 0.1 18:0 1.5 18:1 trans <0.1 18:1 cis 60.1 18:2 trans <0.1 18:2 cis 20.4 18:3 trans <0.1 18:3 cis 9.6 20:0 0.5 20:1 1.2 22:0 0.3 22:1 0.2 24:0 0.1 24:1 0.2

[0180] Table 1: Characteristics of the renewable rapeseed oil feedstock used as feedstock for the hydrotreatment stage.

[0181] Prior to hydrotreatment of the feedstock, the catalyst is sulfurized in situ in the unit, with a distillation diesel fuel with an additive of 2% by weight of dimethyl disulfide, under a total pressure of 5.1 MPa, a hydrogen / additive diesel fuel ratio of 700 Nm3 per m3. The volume of diesel fuel added per volume of catalyst per hour is set at 1 h1. Sulfurization is carried out for 12 hours at 350°C, with a temperature increase ramp of 10°C per hour.

[0182] After sulfurization, the operating conditions of the unit are adjusted in order to carry out the hydrotreatment of the load:

[0183] - WH (charge volume / catalyst volume / hour): 1 h (

[0184] - total working pressure: 5.1 MPa,

[0185] - hydrogen / charge ratio: 700 Nm3 of hydrogen / m3 of charge,

[0186] - temperature: 310°C.

[0187] The hydrogen used is supplied by Air Product and has a purity greater than 99.999% by volume.

[0188] Step b): separation of the effluent from step a)

[0189] All of the hydrotreated effluent from step a) is separated using a gas / liquid separator so as to recover a light fraction containing mainly hydrogen, propane, water in the form of vapor, carbon oxides (CO and CO2) and ammonia and a liquid hydrocarbon effluent consisting mainly of linear hydrocarbons. The water present in the liquid hydrocarbon effluent is removed by decantation. The liquid hydrocarbon effluent thus obtained contains an atomic oxygen content of less than 80 ppm by weight, said atomic oxygen content being measured by the infrared adsorption technique described in patent application US2009 / 0018374, and a sulfur content of 2 ppm by weight and a nitrogen content of less than 1 ppm by weight, said nitrogen and sulfur contents being measured respectively by chemiluminescence and UV fluorescence. The said liquid hydrocarbon effluent has a density of 791 kg / m3.The liquid hydrocarbon effluent is composed of paraffins; its composition, measured by gas chromatography, is provided in Table 2.

[0190] [Tables2] Distribution of n-paraffins by carbon number (%m / m) nC8 0.01 nC9 0.00 nCIO 0.01 nCll 0.01 nC12 0.01 nC13 0.02 nC14 0.06 nC15 0.97 nC16 4.09 nC17 17.70 nC18 72.77 nC19 0.67 nC20 1.56 nC21 0.18 nC22 0.56 nC23 0.09 nC24 0.23 nC25 0.02 nC26 0.02

[0191] Table 2: Composition of the liquid hydrocarbon effluent used as feed for hydroconversion.

[0192] Example 7 not in accordance with the invention: Hydroconversion of the liquid hydrocarbon effluent from example 6 according to a compliant process using the hydroconversion catalyst C2 not in accordance with the invention.

[0193] Example 7 is not in accordance with the invention insofar as it illustrates a process in accordance with the invention but using a catalyst C2 not in accordance with the invention in the hydroconversion step c).

[0194] The hydroconversion catalyst C2 was evaluated in a pilot unit, represented representative in terms of implementation (reaction operating conditions, quality of effluent separation) of the industrial process according to the invention. The different stages and unit operations of the pilot unit mimicking the industrial implementation of the process according to the invention are described below.

[0195] In a reactor regulated in temperature so as to ensure isothermal operation and with a fixed bed loaded with 50 ml of hydroconversion catalyst C2, the catalyst being previously activated by reduction, the hydroconversion of the liquid hydrocarbon effluent from example 6 is carried out. Given the nature of the catalyst C2 (noble metal), any injection of sulfur is to be prohibited.

[0196] Catalyst C2 undergoes a reduction step under hydrogen carried out at 5.1 MPa and 400°C (2-hour stage).

[0197] After reduction, the operating conditions of the unit are adjusted in order to carry out the hydroconversion of the liquid hydrocarbon effluent in the following range of operating conditions:

[0198] - WH (charge volume / catalyst volume / hour) = 0.5 h1,

[0199] - total working pressure: 5.1 MPa,

[0200] - hydrogen / charge ratio: 350 Nm3 of hydrogen / m3 of charge.

[0201] The hydrogen used and entering the hydroconversion stage is supplied by Air Product, it has a purity greater than 99.999% by volume, it is free from hydrogen sulfide.

[0202] At the outlet of the hydroconversion reactor, the reaction effluent is sent to a gas-liquid separation step carried out by means of a flash drum operated at a pressure comparable to that of the hydroconversion reactor. The hydrogen-rich gas phase is sent to the gas outlet of the unit. The liquid hydrocarbon phase is pressure-expanded and sent to a stripper so as to stabilize the liquid effluent; the gas phase collected at the top of the stripper is also sent to the gas outlet of the unit.

[0203] At the unit gas outlet, an online analysis by gas chromatography and a gas meter make it possible to calculate the mass of light hydrocarbons produced (essentially hydrocarbons with 1 to 5 carbon atoms) and present in the hydrogen stream. The liquid effluent is weighed separately, topped at 120°C to remove the naphtha fraction, the 120°C+ liquid effluent is then reweighed and then fractionated using a distillation column into two sub-cuts: a 120-X°C kerosene cut and an X°C+ diesel cut, where X is a temperature that can be adapted by the refiner according to its specificities and the targets it wishes to achieve. A classic example of a value of X can be 280 or 290°C. The sub-cuts are also weighed and analyzed, in particular by measuring the crystal disappearance point (ASTM D5972) of the kerosene cut 120-X°C and by measuring the filterability limit temperature TLF (NF EN 116) of the diesel cut X°C+. None. effluent and none of the cuts are recycled.

[0204] Temperature steps in the range 250 to 400°C were carried out in order to adjust the severity of the hydroconversion. The measurement (typically daily) of the filterability limit temperature makes it possible to monitor the evolution of the catalyst performance at each temperature step. For each temperature, the test duration is extended until a stable filterability limit temperature is obtained.

[0205] The yields of the cuts are then determined from the weighed masses of each cut after fractionation of all of the accumulated 120°C+ liquid effluent. The yield of middle distillates, of the 120-X°C kerosene cut and of the X°C+ diesel cut are calculated as follows:

[0206] Yield 120°C+ (average distillates) = [(liquid effluent mass 120°C+) / (load mass)] x 100, the load corresponding here to the carbon effluent from example 6.

[0207] Yield 120-X°C (kerosene) = [(liquid cut mass 120-X°C) / (charge mass)] x 100, the charge corresponding here is the carbon effluent from example 6.

[0208] Yield X°C+ (diesel) = [(liquid effluent mass X°C+) / (load mass)] x 100, the load corresponding here is the carbon effluent from example 6.

[0209] The mass of distilled 120°C+ liquid effluent corresponds to the quantity of liquid accumulated over a certain period of time, typically 24 hours, and the mass of feed corresponds to the quantity of feed injected into the hydroconversion reactor during the same period of time.

[0210] The temperature adjustment in the reactor was carried out so as to achieve a target limit temperature for filterability of the liquid effluent between -18°C and -20°C. The fractionation was carried out by choosing a cut point of 280°C between the kerosene cut and the diesel cut. The characteristics obtained on the middle distillate cuts of interest, the kerosene cut (120-280°C) and the diesel cut (280°C+), and according to Example 7 as well as the associated operating conditions are reported in summary table 3. The reference temperature is the temperature necessary to achieve the target limit temperature for filterability of the liquid effluent of -18°C using a C2 catalyst not in accordance with the invention, it is noted "base" in table 3.The yield of middle distillate 120°C+ is thus 88% by weight, divided into kerosene cut 120-280°C with a yield of 31% by weight and a crystal disappearance point of -59°C at the required specifications (crystal disappearance point < -40°C), and diesel cut 280°C+ with a yield of 57% by weight and a filterability limit temperature of -11°C higher and not compliant with winter diesel specifications (TLF < -15°C) but compliant with summer diesel specifications (TLF < 0°C).

[0211] Example 8 not in accordance with the invention: Hydroconversion of the liquid hydrocarbon effluent from example 6 according to a compliant process using the hydroconversion catalyst C5 not in accordance with the invention

[0212] Example 8 is not in accordance with the invention insofar as it illustrates a process in accordance with the invention but using a C5 catalyst not in accordance with the invention in the hydroconversion step c).

[0213] The hydroconversion catalyst C5 was evaluated in a pilot unit, representative in terms of implementation (reaction operating conditions, quality of separation of the effluent) of the industrial process according to the invention. The different stages and unit operations of the pilot unit mimicking the industrial implementation of the process according to the invention are described below.

[0214] In a reactor regulated in temperature so as to ensure isothermal operation and with a fixed bed loaded with 50 ml of C5 hydroconversion catalyst, the catalyst being previously activated by reduction, the hydroconversion of the liquid hydrocarbon effluent from example 5 is carried out. Given the nature of the C5 catalyst (noble metal), any injection of sulfur is to be prohibited.

[0215] Catalyst C5 undergoes a reduction step under hydrogen carried out at 5.1 MPa and 400°C (2-hour stage).

[0216] After reduction, the operating conditions of the unit are adjusted in order to carry out the hydroconversion of the liquid hydrocarbon effluent in the following range of operating conditions:

[0217] - WH (charge volume / catalyst volume / hour) = 0.5 h1,

[0218] - total working pressure: 5.1 MPa,

[0219] - hydrogen / charge ratio: 350 Nm3 of hydrogen / m3 of charge.

[0220] The hydrogen used and entering the hydroconversion stage is supplied by Air Product, it has a purity greater than 99.999% by volume, it is free from hydrogen sulfide.

[0221] The daily measurements carried out as well as the operating mode are identical to those detailed in example 7.

[0222] The temperature is adjusted in the range 250°C to 400°C in order to reach the same target limit temperature for filterability of the liquid effluent as in Example 7. The fractionation cut points are also the same as in Example 7. The characteristics obtained on the cuts of interest, the kerosene cut (120-280°C) and the diesel cut (280°C+), and according to Example 8 as well as the associated operating conditions are reported in summary table 3. The reference temperature is the temperature necessary to reach the target limit temperature for filterability of the liquid effluent of -18°C using a C2 catalyst not in accordance with the invention.

[0223] For the same cold property target of the liquid effluent at the outlet of the hydroconversion reactor, catalyst C5 is 7°C more active than catalyst C2.

[0224] Furthermore, catalyst C5 makes it possible to obtain a yield of average distillate at 120°C + of 90% by weight, higher than catalyst C2 by 2 points.

[0225] On the other hand, the kerosene cut yield obtained with catalyst C2 is 15 points higher while the diesel cut yield is 17 points lower compared to the yields obtained with catalyst C5 and the same fractionation cut points.

[0226] The 120-280°C kerosene cut obtained by distillation has a crystal disappearance point of -43°C in accordance with the required specifications and the 280°C+ diesel cut has a filterability limit temperature of -15°C in accordance with the winter diesel specifications (TLF < -15°C).

[0227] Example 9 not in accordance with the invention: Hydroconversion of the liquid hydrocarbon effluent from example 6 according to a non-compliant process using the hydroconversion catalyst C3 in accordance with the invention.

[0228] Example 9 is not in accordance with the invention insofar as said illustrated process comprises a step of stabilizing the hydroconverted effluent for the production of kerosene and not a step of fractionating said effluent for co-production of diesel and kerosene, the hydroconversion step being carried out on the compliant C3 catalyst.

[0229] The hydroconversion catalyst C3 was evaluated in a pilot unit, representative in terms of implementation (reaction operating conditions, quality of separation of the effluent) of the industrial process according to the invention. The different stages and unit operations of the pilot unit mimicking the industrial implementation of the process according to the invention are described below.

[0230] In a reactor regulated in temperature so as to ensure isothermal operation and with a fixed bed loaded with 50 ml of hydroconversion catalyst C3, the catalyst being previously activated by reduction, the hydroconversion of the liquid hydrocarbon effluent from example 6 is carried out. Given the nature of the catalyst C3 (noble metal), any injection of sulfur is to be prohibited.

[0231] Catalyst C3 undergoes a reduction step under hydrogen carried out at 5.1 MPa and 400°C (2-hour stage).

[0232] After reduction, the operating conditions of the unit are adjusted in order to carry out the hydroconversion of the liquid hydrocarbon effluent in a range of operating conditions identical to that of example 7 and in the strict absence of sulfur, i.e.:

[0233] - WH (charge volume / catalyst volume / hour) = 0.5 h (

[0234] - total working pressure: 5.1 MPa,

[0235] - hydrogen / charge ratio: 350 Nm3 of hydrogen / m3 of charge.

[0236] The hydrogen used and entering the hydroconversion stage is supplied by Air Product, it has a purity greater than 99.999% by volume, it is free from hydrogen sulfide.

[0237] At the outlet of the hydroconversion reactor, the reaction effluent is sent to a stage gas-liquid separation carried out using a flash drum operated at a pressure comparable to that of the hydroconversion reactor. The hydrogen-rich gas phase is sent to the gas outlet of the unit. The liquid hydrocarbon phase is pressure-reduced and sent to a stripper so as to stabilize the liquid effluent; the gas phase collected at the top of the stripper is also sent to the gas outlet of the unit.

[0238] At the unit gas outlet, an online analysis by gas chromatography and a gas meter make it possible to calculate the mass of light hydrocarbons produced (essentially hydrocarbons having 1 to 5 carbon atoms) and present in the hydrogen flow. The liquid effluent is weighed separately, topped at 120°C to eliminate the naphtha fraction, the 120°C+ liquid effluent is then reweighed and analyzed, in particular by a crystal disappearance point (ASTM D5972) in kerosene target.

[0239] Temperature steps in the range 250 to 400°C were carried out in order to adjust the severity of the hydroconversion. The measurement (typically daily) of the crystal disappearance point makes it possible to monitor the evolution of the catalyst performance at each temperature step. For each temperature, the test duration is extended until a stable crystal disappearance point is obtained.

[0240] Once the crystal disappearance point is stable, the yield in the 120°C+ cut (kerosene) is determined according to the following calculation:

[0241] Yield 120°C+ (average distillates) = [(liquid effluent mass 120°C+) / (load mass)] x 100, the load corresponding here to the carbon effluent from example 6.

[0242] Yield 120°C+ (kerosene) = Yield 120°C+ (average distillates)

[0243] The 120°C+ liquid effluent mass corresponds to the quantity of 120°C+ liquid accumulated over a certain period of time, typically 24 hours, and the feed mass corresponds to the quantity of feed injected into the hydroconversion reactor during the same period of time.

[0244] The temperature adjustment in the reactor was carried out so as to reach the target cold property of the following fuel: kerosene. The characteristics obtained on the 120°C+ cut of interest and according to example 9 as well as the associated operating conditions are reported in summary table 3. The reference temperature is the temperature necessary to reach a filterability limit temperature of -18°C of the liquid effluent using a C2 catalyst not in accordance with the invention, it is noted “base” in table 3.

[0245] An increase of 3°C in the “base” temperature thus makes it possible to reach a kerosene target (crystal disappearance point < -40°C) with the C3 catalyst. The yield of 120°C+ middle distillate is 83% by weight for the kerosene target. In the absence of fractionation and under kerosene target conditions, the yield of 120°C+ kerosene cut is 83% by weight (the same as for 120°C+ middle distillate) and no diesel cut is produced.

[0246] Non-compliant example 10: Hydroconversion of the liquid hydrocarbon effluent from example 6 according to a non-compliant process using the C4 hydroconversion catalyst in accordance with the invention.

[0247] Example 10 is not in accordance with the invention insofar as said illustrated process comprises a step of stabilizing the hydroconverted effluent for the production of kerosene and not a step of fractionating said effluent for the coproduction of diesel and kerosene, the hydroconversion step being carried out on the compliant C4 catalyst.

[0248] The C4 hydroconversion catalyst in accordance with the invention was evaluated in a pilot unit, representative in terms of implementation (reaction operating conditions, quality of separation of the effluent) of the industrial process according to the invention. The different stages and unit operations of the pilot unit mimicking the industrial implementation of the process according to the invention are described below.

[0249] In a reactor regulated in temperature so as to ensure isothermal operation and with a fixed bed loaded with 50 ml of C4 hydroconversion catalyst, the catalyst being previously activated by reduction, the hydroconversion of the liquid hydrocarbon effluent from Example 6 is carried out. Given the nature of the C4 catalyst (noble metal), any injection of sulfur is to be prohibited.

[0250] Catalyst C4 undergoes a reduction step under hydrogen carried out at 5.1 MPa and 400°C (2-hour stage).

[0251] After reduction, the operating conditions of the unit are adjusted in order to carry out the hydroconversion of the liquid hydrocarbon effluent in a range of operating conditions identical to that of example 7, in the strict absence of sulfur, i.e.: - WH (charge volume / catalyst volume / hour) = 0.5 h1, - Total working pressure: 5.1 MPa, - Hydrogen / charge ratio: 350 Nm3 of hydrogen / m3 of charge.

[0252] The hydrogen used and entering the hydroconversion stage is supplied by Air Product and has a purity greater than 99.999% by volume, it is free from hydrogen sulfide.

[0253] The daily measurements carried out as well as the operating mode are identical to those detailed in example 9.

[0254] The temperature levels are adjusted in the range 250°C to 400°C in order to achieve the same fuel targets as in example 9. For each target, the characteristics obtained on the 120°C+ cut of interest and according to example 10 are reported in summary table 3. The reference temperature is the temperature necessary to achieve a filterability limit temperature of -18°C of the liquid effluent using a C2 catalyst not in accordance with the invention, it is noted “base” in table 3.

[0255] For a kerosene target (crystal disappearance point < -40°C), the temperature used with the C4 catalyst is 3°C lower than the “base” temperature. The yield of 120°C+ middle distillate is 83% by weight. In the absence of fractionation and under kerosene target conditions, the yield of 120°C+ kerosene cut is 83% by weight (the same as for 120°C+ middle distillate) and no diesel cut is produced.

[0256] Example 11 compliant: Hydroconversion of the liquid hydrocarbon effluent from Example 6 according to a compliant process using the hydroconversion catalyst C3 in accordance with the invention followed by a step of fractionation of the hydroconverted effluent.

[0257] The hydroconversion catalyst C3 was evaluated in a pilot unit, representative in terms of implementation (reaction operating conditions, quality of separation of the effluent) of the industrial process according to the invention. The different stages and unit operations of the pilot unit mimicking the industrial implementation of the process according to the invention are described below.

[0258] In a reactor regulated in temperature so as to ensure isothermal operation and with a fixed bed loaded with 50 ml of hydroconversion catalyst C3, the catalyst being previously activated by reduction, the hydroconversion of the liquid hydrocarbon effluent from example 6 is carried out. Given the nature of the catalyst C3 (noble metal), any injection of sulfur is to be prohibited.

[0259] Catalyst C3 undergoes a reduction step under hydrogen carried out at 5.1 MPa and 400°C (2-hour stage).

[0260] After reduction, the operating conditions of the unit are adjusted in order to carry out the hydroconversion of the liquid hydrocarbon effluent in the following range of operating conditions:

[0261] - WH (charge volume / catalyst volume / hour) = 0.5 h (

[0262] - total working pressure: 5.1 MPa,

[0263] - hydrogen / charge ratio: 350 Nm3 of hydrogen / m3 of charge.

[0264] The hydrogen used and entering the hydroconversion stage is supplied by Air Product, it has a purity greater than 99.999% by volume, it is free from hydrogen sulfide.

[0265] The daily measurements carried out as well as the operating mode are identical to those detailed in example 7.

[0266] The temperature is adjusted in the range 250°C to 400°C in order to reach the same target limit temperature of filterability of the liquid effluent as in Example 7. The fractionation cut points are also the same as in Example 7. The characteristics obtained on the cuts of interest, the kerosene cut (120-280°C) and the diesel cut (280°C+), and according to Example 11 as well as the operating conditions associated are reported in summary table 3. The reference temperature is the temperature necessary to reach the target limit temperature for filterability of the liquid effluent of -18°C using a C2 catalyst not in accordance with the invention.

[0267] For a filterability limit temperature target of -18°C of the liquid effluent at the outlet of the hydroconversion reactor, catalyst C3 is 7°C more active than catalyst C2 and has the same activity as catalyst C5. In addition, catalyst C3 makes it possible to obtain a yield of middle distillate 120°C+ of 93% by weight, 5 points higher than catalyst C2 and 3 points higher than catalyst C5.

[0268] The fractionation step allows for co-production of diesel and kerosene to the required specifications. On the other hand, in a process without a fractionation step, such as that of Example 9, no diesel cut is produced.

[0269] Furthermore, in the process with fractionation step according to the invention, the temperature necessary to co-produce a fuel with winter diesel specifications and a fuel with kerosene specifications is 10°C lower than that of the process without fractionation with a kerosene target of example 9. Logically, the yield of middle distillate 120°C+ with the fractionation step is 93% by weight, 10 points higher than that obtained with the process without fractionation step of example 9.

[0270] The combination of the C3 catalyst with the process with a fractionation step makes it possible to have a co-production of diesel and kerosene to the required specifications and to maximize the yield of middle distillate 120°C+, by operating at more moderate temperatures and thus extending the life cycle of the catalyst.

[0271] Example 12 compliant: Hydroconversion of the liquid hydrocarbon effluent from Example 6 according to a compliant process using the hydroconversion catalyst C4 compliant with the invention followed by a step of fractionation of the hydroconverted effluent.

[0272] The C4 hydroconversion catalyst was evaluated in a pilot unit, representative in terms of implementation (reaction operating conditions, quality of separation of the effluent) of the industrial process according to the invention. The different stages and unit operations of the pilot unit mimicking the industrial implementation of the process according to the invention are described below.

[0273] In a reactor regulated in temperature so as to ensure isothermal operation and with a fixed bed loaded with 50 ml of C4 hydroconversion catalyst, the catalyst being previously activated by reduction, the hydroconversion of the liquid hydrocarbon effluent from Example 6 is carried out. Given the nature of the C4 catalyst (noble metal), any injection of sulfur is to be prohibited.

[0274] Catalyst C4 undergoes a reduction step under hydrogen carried out at 5.1 MPa and 400°C (2-hour stage).

[0275] After reduction, the operating conditions of the unit are adjusted in order to carry out the hydroconversion of the liquid hydrocarbon effluent in the following range of operating conditions:

[0276] - WH (charge volume / catalyst volume / hour) = 0.5 h (

[0277] - total working pressure: 5.1 MPa,

[0278] - hydrogen / charge ratio: 350 Nm3 of hydrogen / m3 of charge.

[0279] The hydrogen used and entering the hydroconversion stage is supplied by Air Product, it has a purity greater than 99.999% by volume, it is free from hydrogen sulfide.

[0280] The daily measurements carried out as well as the operating mode are identical to those detailed in example 7.

[0281] The temperature is adjusted in the range 250°C to 400°C in order to reach the same target limit temperature for filterability of the liquid effluent as in Example 7. The fractionation cut points are also the same as in Example 7. The characteristics obtained on the cuts of interest, the kerosene cut (120-280°C) and the diesel cut (280°C+), and according to Example 12 as well as the associated operating conditions are reported in summary table 3. The reference temperature is the temperature necessary to reach the target limit temperature for filterability of the liquid effluent of -18°C using a C2 catalyst not in accordance with the invention.

[0282] For a filterability limit temperature target of -18°C of the liquid effluent at the outlet of the hydroconversion reactor, catalyst C4 is 14°C more active than catalyst C2 and 7°C more active than catalyst C5. In addition, catalyst C4 makes it possible to obtain a yield of middle distillate 120°C+ of 95% by weight, 7 points higher than catalyst C2 and 5 points higher than catalyst C5.

[0283] The fractionation step in the process allows for co-production of diesel and kerosene to the required specifications. On the other hand, in a process without a fractionation step, such as that of Example 10, no diesel cut is produced.

[0284] Furthermore, in the process with fractionation step according to the invention, the temperature necessary to co-produce a fuel with winter diesel specifications and a fuel with kerosene specifications is 11°C lower than that of the process without fractionation with a kerosene target of example 9. Logically, the yield of middle distillate 120°C+ with the fractionation step is 95% by weight, 12 points higher than that obtained with the process without fractionation step of example 9.

[0285] The combination of the C4 catalyst with the process with a fractionation step makes it possible to have a co-production of diesel and kerosene to the required specifications and to maximize the yield of middle distillate 120°C+, by operating at more moderate temperatures and thus extending the life cycle of the catalyst. 40

[0286] [Tables3] Example 7 non-compliant Example 8 non-compliant Example 9 non-compliant Example 10 non-compliant Example 11 compliant Example 12 compliant Catalyst C2 C5 C3 C4 C3 C4 Operating conditions Temperature °C Base Base- 7 Base+ 3 Base- 3 Base- 7 Base- 14 Total pressure (MPa) MPa 5.1 5.1 5.1 5.1 5.1 5.1 H2 / charge ratio NmW 350 350 350 350 350 350 Charge volume / catalyst volume / h h1 0.5 0.5 0.5 0.5 0.5 0.5 Middle distillate yield 120°C+ % wt / charge 88 90 83 83 93 95 Diesel Cut Diesel cut yield % wt / charge 57 74 76 79 Diesel cut properties Cutting point °C 280°C + 280°C + 280°C + 280°C + Temperature Filtration limit °C -11 -15 -15 -16 Density at 15°C g / cm3 0.787 0.781 0.786 0.787 Cetane index - >60 >60 >60 >60 Sulphur content ppm wt < 10 < 10 < 10 < 10 Nitrogen content ppm wt < 1 < 1 < 1 < 1 Kerosene Cut Kerosene cut yield % wt / charge 31 16 83 83 17 16 Cut properties kerosene Cutting point °C 120-28 0 120-2 80 120°C + 120°C + 120-2 80 120-2 80 Crystal disappearance point °C -59 -43 -52 -51 -42 -41 Density at 15°C g / cm3 0.752 0.756 0.771 0.772 0.759 0.760 Smoke point mm >25 >25 >25 >25 >25 >25 Sulphur content ppm wt < 10 < 10 < 10 < 10 < 10 < 10 Nitrogen content ppm wt < 1 < 1 < 1 < 1 < 1 < 1

[0287] Table 3: yields and properties of the diesel and kerosene cuts obtained for the different examples of the invention.

[0288] Example 13 compliant / Hydroconversion of a mixture of long n-paraffins (from the Fischer-Tropsh process) and n-paraffins produced by the hydrotreatment of vegetable oil (Rapeseed) according to a process in accordance with the invention.

[0289] The feedstock is composed of 15% hydrotreated waxes from the Fischer-Tropsch process and 85% n-paraffins produced by the hydrotreatment of rapeseed oil. The distillation curves of each of the feedstocks constituting the mixture are shown in the figure opposite. The 370°C+ content of the resulting mixture is around 10%.

[0290] It is treated in hydrotreatment steps a) and separation b) in accordance with the conditions set out in Example 6.

[0291] In a reactor regulated in temperature so as to ensure isothermal operation and with a fixed bed loaded with 40 ml of C4 hydroconversion catalyst in accordance with the invention, the catalyst being previously activated by reduction, the hydroconversion of the mixture of charges described is carried out. Given the nature of the catalyst according to the invention, any injection of sulfur is to be prohibited.

[0292] The catalyst undergoes a reduction step under hydrogen carried out at 5.1 MPa and 400°C (2-hour stage).

[0293] After reduction, the operating conditions of the unit are adjusted in order to carry out the hydroconversion of the mixture in the range of operating conditions indicated below and in the strict absence of sulfur, namely:

[0294] - WH (charge volume / catalyst volume / hour) = 0.5 h1,

[0295] - total working pressure: 5.1 MPa,

[0296] - hydrogen / charge ratio: 350 Nm3 of hydrogen / m3 of charge.

[0297] The hydrogen stream used and entering the hydroconversion stage is supplied by Air Product, it has a purity greater than 99.999% by volume, it is free of hydrogen sulfide.

[0298] The temperature steps are adjusted in the range 250°C to 400°C in order to progressively tighten the conversion of the long n-paraffins (Fischer-Tropsch waxes) contained in the feed mixture. At each temperature, the conversion of the long paraffins (C22+) is evaluated by taking as descriptor the conversion 370°C+ defined as follows: = X 1Ï3S

[0299] At each temperature level, once the performance has stabilized, the reaction effluent is sampled. This is then analyzed and fractionated using a distillation column. The cuts produced by the distillation step are as follows: a PL130°C naphtha cut, a kerosene cut 130-295°C, a diesel cut 295-370°C and finally a heavy unconverted cut 370°C+. The various by-products are also analyzed.

[0300] In a method according to the invention, the main performances obtained are as follows: - Activity: The hydroconversion catalyst according to the invention exhibits very satisfactory isomerizing and cracking activity on long paraffins (C22+) derived from Fischer-Tropsch waxes. Temperature adjustment demonstrated the achievement of high conversion levels (> 90%), under reasonable temperature conditions, i.e. compatible with the conditions imposed on more conventional lipid feedstocks (vegetable oils). - Selectivity: At each temperature / conversion step 370°C+, the selectivity towards the different cuts was evaluated. The maximization of kerosene yields was observed at high conversion. The yields towards the different cuts (naphtha / kerosene / diesel / unconverted) are given in Table 4. Properties of the kerosene and diesel cuts of interest: At each temperature / conversion level 370°C+, a fractionation of the collected liquid effluent was carried out in accordance with the invention so as to be able to analyze and characterize the different products. It was observed that the kerosene / diesel cuts generated in a process according to the invention comply with the main specifications required (Table 4).

[0301] Table 4: Selectivity and main product properties obtained at 70% of conversion 370°C+

[0302] [Tables4] Yields obtained for a conversion 370°C+ = 70% (% by charge ratio) Characteristics of the main cuts of interest Naphtha (PI-130°C) 16% - Kerosene (130-295°C) 44% Crystal disappearance point < -40°C End point ASTM D86 < 300°C Flash point > 38°C Diesel (295-370°C) 34% Filterability limit temperature < -15°C T95 point ASTM D86 < 360°C Flash point > 55°C Unconverted (370°C+) <4% -

[0303] Thus, the possibility of hydroconverting long n-paraffins (here Fischer-Tropsh waxes) in co-processing with n-paraffins produced by the hydrotreatment of a vegetable oil is possible and proven according to a process in accordance with the invention. This result is based on two major advantages of the process in accordance with the invention: - The use of a specific hydroconversion catalyst which allows the isomerization of long n-paraffins but also their cracking at a reasonable temperature. - The fractionation stage which allows the co-production of cuts such as kerosene / diesel and a heavy unconverted fraction as well as the adjustment of the cut points to best meet the fuel specifications.

[0304] Example 14 not in accordance: Hydroconversion of a mixture of long n-paraffins (from the Fischer-Tropsh process) and n-paraffins produced by the hydrotreatment of vegetable oil (rapeseed) according to a process not in accordance with the invention.

[0305] In a process not in accordance with the invention, the effluent stabilization / separation step located downstream of the hydroconversion step allows the production of a broad cut of middle distillates (preferably it comprises compounds with a boiling point above 120-130°C) but does not allow the co-production of two diesel and kerosene interest cuts.

[0306] When the feedstock consists of a fraction of very heavy compounds, such as those present in n-paraffins from Fischer-Tropsh waxes ([Fig.l]), it appears obvious to those skilled in the art that compliance with fuel specifications (in particular those relating to the end point of the products) will not be permitted without trimming the middle distillate cut.

[0307] In other words, in a process not in accordance with the invention, the absence of fractionation prevents the adjustment of the distillation interval of the diesel and / or kerosene cuts of interest and therefore makes the co-treatment of the conventional lipid charge with heavier compounds such as those described very complicated or even impossible.

Claims

Claims

1. A process for treating a feedstock from a renewable source to simultaneously produce a diesel cut and a kerosene cut, said process comprising at least the following steps, and preferably consisting of the following steps: a) a step of hydrotreating said feedstock in the presence of a fixed-bed catalyst, said catalyst comprising a hydrogenating function and an oxide support, at a temperature of between 200 and 450°C, at a pressure of between 1 and 10 MPa, at an hourly space velocity of between 0.1 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 2000 Nm3 of hydrogen / m3 of feedstock, b) a step of separating at least a portion of the effluent from step a) into at least one light gaseous fraction, at least one hydrocarbon liquid effluent, and at least one aqueous liquid effluent,c) a step of hydroconversion of at least a portion of the liquid hydrocarbon effluent from step b) in the presence of at least one bifunctional fixed-bed hydroconversion catalyst, said catalyst comprising a hydrogenating phase comprising at least one noble metal from group VIII of the periodic table chosen from platinum and palladium and a support comprising at least one zeolite chosen from zeolites with structural code MTW, and zeolite IZM-2 alone or as a mixture, and at least one binder, said hydroconversion step being carried out at a temperature of between 250 and 500°C, at a pressure of between 1 and 10 MPa, at an hourly space velocity of between 0.1 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 1000 Nm3 / m3 of feedstock,d) a step of separating at least part of the effluent from step c) which makes it possible to separate at least one gaseous fraction, and at least one liquid hydrocarbon effluent, e) a step of fractionating the liquid hydrocarbon effluent from step d) into at least one kerosene cut and at least one diesel cut, no recycling step in step a) of hydrotreatment and / or step c) of hydroconversion, of all or part of the effluents from step c) of hydroconversion, of the effluents from step d) of separation and / or of the, effluents from fractionation step e) not being implemented.

2. Process according to claim 1 in which the feedstock from renewable sources is chosen from oils and fats of vegetable or animal origin, used cooking oils, oils of microbial origin, fish oils, long paraffins from the Fischer-Tropsch process, crude or having undergone prior treatment, or mixtures of such feedstocks, containing triglycerides and / or free fatty acids and / or esters.

3. Process according to one of claims 1 or 2 wherein in step a), the feed is brought into contact with a fixed-bed catalyst at a temperature of between 220 and 350°C, at a pressure of between 1 and 6 MPa, at an hourly space velocity of between 0.1 and 10 h1. The feed is brought into contact with the catalyst in the presence of hydrogen and in the presence of a total quantity of hydrogen mixed with the feed such that the hydrogen / feed ratio is between 150 and 1000 Nm3 of hydrogen / m3 of feed.

4. Process according to one of claims 1 to 3 in which the hydrotreatment catalyst used in step a) comprises a hydro-dehydrogenating function comprising at least one metal from group VIII and / or group VIB, taken alone or as a mixture and a support chosen from the group formed by alumina, silica, silica-aluminas, magnesia, clays and mixtures of at least two of these minerals.

5. Process according to one of claims 1 to 4 in which the separation step b) is implemented by the combination of one or more high and / or low pressure separators, and / or high and / or low pressure distillation and / or stripping steps.

6. Process according to one of claims 1 to 5 in which the hydroconversion step c) operates at a temperature of between 250 and 450°C, and very preferably, between 250 and 400°C, at a pressure of between 2 and 10 MPa and very preferably, between 3 and 9 MPa, at an hourly volumetric flow rate advantageously of between 0.2 and 7 h 1 and very preferably, between 0.5 and 5 h1, at a hydrogen flow rate such that the hydrogen / feed volume ratio is advantageously between 100 and 1000 normal m3 of hydrogen per m3 of feed and preferably between 150 and 1000 normal m3 of hydrogen per m3 of feed.

7. Process according to one of claims 1 to 6 in which the group VIII metal of the catalyst used in step c) is platinum.

8. Process according to one of claims 1 to 7 in which the zeolite with structural code MTW used in the catalyst of step c) is ZSM-1 0

9. 1Z. Process according to one of claims 1 to 8 in which the catalyst used in step c) comprises a hydrogenating phase comprising platinum and a support comprising an IZM-2 zeolite alone and an alumina binder.

10. Process according to one of claims 1 to 8 in which the catalyst used in step c) comprises a hydrogenating phase comprising platinum and a support comprising a ZSM-12 zeolite alone and an alumina binder.

11. Process according to one of claims 1 to 10 in which the fractionation step e) is carried out in a distillation column or in a steam stripping step followed by a distillation column.

12. Method according to one of claims 1 to 11 in which at least one heavy cut having a boiling temperature above 350°C, preferably above 370°C is separated in said fractionation step e).

13. Process according to one of claims 1 to 12 in which the process does not comprise a hydrocracking step downstream of step c) of hydroconversion of part or all of the effluent from step c).

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