Method for stabilizing nitrogen-rich oil

Abstract

The present invention relates to a process for hydrotreating a nitrogen-rich liquid oil stream by reacting the nitrogen-rich liquid oil stream with hydrogen in a continuous operation in a fixed bed reactor in the presence of a catalyst at a temperature of 80-250 DEG C, a pressure of 10-200 barg, a liquid hourly space velocity (LHSV) of 0.1-6 h <-1 > to form a stable liquid oil stream.

Description

Technical Field

[0001] The present invention relates to a method for hydrotreating a nitrogen-rich liquid oil stream by continuously operating in a fixed-bed reactor, in the presence of a catalyst, at a reaction temperature of 80 - 250 °C, a pressure of 10 - 200 barg, and a liquid hourly space velocity (LHSV) of 0.1 - 6 h -1 to react the nitrogen-rich liquid oil stream with hydrogen to form a stable liquid oil stream. Background Art

[0002] The field of renewable raw materials has been receiving extensive attention not only in Europe, but also in the United States and China. Hydrocarbon products used as transportation fuels, particularly any one of marine fuels, diesel, aviation fuel, and naphtha, and petrochemical raw materials, such as steam cracker feedstock, can be sustainably produced using renewable raw materials.

[0003] Compared to oils derived from wood or straw, oils derived from nitrogen-rich renewable sources such as sewage sludge, algae, or other nitrogen-rich renewable sources have a stronger tendency to polymerize.

[0004] If the oil derived from nitrogen-rich raw materials is not stabilized, it will quickly coke and block the catalyst bed. If stabilized using the same method as pyrolysis oil derived from lignocellulosic biomass, ultra-high pressure, ultra-low LHSV, and very expensive catalysts are required, resulting in very high CAPEX.

[0005] WO 2022 / 152900 describes a method for stabilizing liquid oil at low temperature.

[0006] Zacher et al “Technology Advancements in Hydroprocessing of Bio-oil”, Biomass and Bioenergy, 125 (2019) 151 - 168 teaches that oils with a carbonyl content of 1.3 mmol / g have sufficient stability to be hydrotreated at 400 °C. Since the low-temperature stabilization step increases the cost and complexity of the process, this teaching implies that this step should be avoided.

[0007] However, it has been found that this is not the case if the feed oil has a high N content. Feeds with a high N content and a carbonyl content between <0.5 - 1.13 mmol / g may cause reactor blockage at an operating temperature of 300 °C.

[0008] This technology has discovered a new problem, namely, for feeds with a relatively low carbonyl group content (e.g., above the detection limit but below 1.13 mmol / g) and a relatively high nitrogen concentration, there is a risk of clogging the reactor. An object of the present invention is to provide a stable renewable crude oil and a method for forming the same, which can be further hydrotreated under more conventional hydrotreating conditions. Summary of the Invention

[0009] The inventors of the present invention have found that if a feed with a high N content but a low carbonyl content is pre-stabilized, the clogging of the hydrotreating reactor can be reduced or even avoided.

[0010] Therefore, a first aspect of the present invention relates to a method for hydrotreating a nitrogen-rich liquid oil stream, by continuously operating in a fixed-bed reactor, in the presence of a catalyst, at a temperature of 80 - 250 °C, a pressure of 10 - 200 barg, and a liquid hourly space velocity (LHSV) of 0.1 - 6 h -1 to react the nitrogen-rich liquid oil stream with hydrogen to form a stable liquid oil stream. Detailed Description of the Invention

[0011] The unit "barg" represents the pressure above atmospheric pressure (atmospheric pressure: approximately 1 bar).

[0012] There is provided a method for hydrotreating a nitrogen-rich liquid oil stream, the nitrogen-rich liquid oil stream containing at least 0.5 wt% of nitrogen and 0.5 mmol / g to 1.13 mmol / g of carbonyl groups, by continuously operating in a fixed-bed reactor, in the presence of a catalyst, at a temperature of 80 - 250 °C, a pressure of 10 - 200 barg, and a liquid hourly space velocity (LHSV) of 0.1 - 6 h -1 to react the nitrogen-rich liquid oil stream with hydrogen to form a stable liquid oil stream. The combination of the above features enables the stabilization of the liquid oil.

[0013] In a preferred embodiment, the temperature is 180 - 220 °C, such as 190 - 200 °C. In another embodiment, the pressure is 80 - 175 barg, such as 150 barg. In another embodiment, the LHSV is 0.2 - 4.0 h -1 , such as 0.2 - 0.2 h -1 , or 0.8 - 1.0 h -1 , such as 0.9 h -1 .

[0014] In another embodiment, the temperature is 180 - 220 °C, such as 190 - 200 °C. In another embodiment, the pressure is 15 - 80 barg, such as 50 barg. In another embodiment, the LHSV is 0.2 - 4.0 h -1, for example, 0.2 - 0.2 h -1 , or 0.8 - 1.0 h -1 , for example, 0.9 h -1 .

[0015] The temperature range of 80 - 250 °C includes the inlet temperature of the liquid oil stream and the outlet temperature of the stable liquid oil stream. Preferred temperature ranges include 100 - 250 °C, 120 - 250 °C, and 150 - 250 °C. The process is exothermic, so the temperature may increase by 100 °C or more. The higher the inlet temperature, such as 80 °C, the easier it is for the process to ignite to initiate the exotherm. The outlet temperature can be, for example, 150 or 200 or 240 °C. More generally, the temperature in a given step or its reactor (unit) refers to the inlet temperature in an adiabatic step or the reaction temperature in an isothermal step.

[0016] By the present invention, a continuous operation method is adopted. Since it is contrary to batch operation, it does not depend on the output product (stable liquid oil) always being a fluid. The term "continuous operation", as is well known in the art, means that in a given production cycle, the incoming liquid oil stream is continuous, and the stable liquid oil stream taken out as the output product is also continuous. This is in contrast to the batch operation well known in the art, i.e., discontinuous operation, in which the entire amount of liquid oil and catalyst is introduced at the start of the process and the product is taken out after a certain time.

[0017] Suitably, the ratio of hydrogen to liquid oil in the present process (defined as the volume ratio of hydrogen to the liquid oil stream) is 100 - 8000 NL / L, for example, 2000 - 5000 NL / L.

[0018] The present invention also conducts the process at a ratio of hydrogen to liquid oil of 1000 - 6000 NL / L, for example, 2000 - 5000 NL / L, for example, 2500, 3000, 3500, 4000, or 4500 NL / L. The term "ratio of hydrogen to liquid oil" or "H2 / oil ratio" as used herein refers to the volume ratio of hydrogen to the liquid oil stream. It should be understood that the unit NL refers to "standard" liters, i.e., the amount of gas that occupies that volume at 0 °C and 1 atmosphere. The volume of the liquid oil is determined at 15 °C and 1 atmosphere according to the practice in the art.

[0019] In one embodiment, the liquid oil stream contains at least 2 wt% of N, or at least 5 wt% of N. The liquid oil stream can contain 10 wt% of nitrogen (N), for example, at least 2 wt% of N, or at least 5 wt% of N. The nitrogen content is suitably determined by standard elemental analysis.

[0020] In one embodiment, the liquid oil stream contains at least 0.5 wt% oxygen (O), such as at least 2 wt% O, or at least 4 wt% O. The oxygen content is suitably determined by standard elemental analysis.

[0021] On the one hand, the microcarbon residue (MCR) of the liquid oil stream before hydrotreating, as determined according to ASTM D 4530, is 5 - 20 wt%, such as 5 - 15 wt%, because such elevated MCR values indicate a tendency for coke deposition. After hydrotreating, as determined according to ASTM D 4530, the microcarbon residue (MCR) of the stable liquid oil stream is suitably below 5 wt%, such as below 4.5 wt%, indicating a lower tendency for coke deposition.

[0022] In one embodiment, the liquid oil stream is a pyrolysis oil stream or a hydrothermal liquefaction oil (HTL oil) stream. In one embodiment, the liquid oil stream is an oil stream derived from a thermochemical decomposition process (such as pyrolysis or hydrothermal liquefaction), which is part of the same process equipment or separate process equipment. In one embodiment, the liquid oil stream is a pyrolysis oil stream, which, as determined by ASTM E3146 - 20, contains at least 0.5 mol / kg of one or more of the following: aldehyde compounds, ketones, alcohols, furfural. In one embodiment, the liquid oil stream may be characterized by an elemental composition of 50 wt% to 70 wt%, 80 wt% or 85 wt% C and 2 wt%, 3 wt%, 5 wt% or 10 wt% to 50 wt% O, which is an exemplary elemental composition range for liquid non - aqueous thermochemical decomposition products such as pyrolysis oil streams or hydrothermal liquefaction oil (HTL oil) streams. 14 C / 12 The C / C isotope ratio can be from 0.5 to 2 per trillion, which defines the isotopic composition of a sample of biological origin.

[0023] In one aspect, the catalyst is Ni - based, Mo - based, CoMo - based, NiMo - based, W - based, NiW - based or Ru - based, optionally in sulfided or reduced form.

[0024] When a catalyst is "based on" a particular metal (e.g., based on Ni), this means that the listed metals Ni, Mo, …… account for at least 90 wt%, 99% or 100% of the Group 1-12 materials in the catalyst. The following ranges are provided for each category: based on Ni (2-30 wt% Ni, sulfided or reduced), based on Mo (2-30 wt% Mo, preferably sulfided), based on CoMo (1-10 wt% Co, 2-30 wt% Mo, preferably sulfided), based on NiMo (1-10 wt% Ni, 2-30 wt% Mo, preferably sulfided), based on W (2-30 wt% W, preferably sulfided), based on NiW (1-10 wt% Ni, 2-30 wt% W, preferably sulfided) or based on Ru (0.1-10 wt%, preferably reduced), optionally in sulfided or reduced form.

[0025] In one aspect of the method, the catalyst is a supported catalyst having a Mo content of 2-30 wt% and an optional P content of 0-3 wt% based on the total weight of the catalyst. The support can be selected from alumina, silica, titania and combinations thereof; optionally in combination with a solid acid such as silica-alumina or a molecular sieve having a topology MFI, BEA or FAU. The term "topology MFI, BEA or FAU" as used herein refers to the structures specified and maintained by the Structure Commission of the International Zeolite Association in the Atlas of Zeolite Framework Types (see http: / / www.iza-structure.org / databases / ), or structures defined, for example, also in "Atlas of Zeolite Framework Types", by Ch. Baerlocher, L. B. McCusker and D. H. Olson, Sixth Revised Edition 2007.

[0026] The method may also include a prior step of thermally decomposing a solid renewable feedstock to produce the liquid oil stream. The term "thermally decomposing" as used herein, for convenience, should be used broadly for any decomposition process in which a material is partially decomposed at an elevated temperature (typically 250 °C to 800 °C or even 1000 °C) in the presence of sub-stoichiometric oxygen (including no oxygen). The product is typically a combined stream of liquid and gas, as well as a certain amount of solid carbon. The term should be interpreted to include processes known as pyrolysis and hydrothermal liquefaction carried out with or without a catalyst.

[0027] Thus, in a specific embodiment, the thermal decomposition is pyrolysis, such as fast pyrolysis, to produce the pyrolysis oil stream. It should be understood that the thermal decomposition takes place in the thermal decomposition section, and thus the pyrolysis takes place in the pyrolysis section, while the hydrothermal liquefaction takes place in the hydrothermal liquefaction section. The term "section" as used herein refers to a physical part that includes a unit or combination of units for performing one or more steps and / or sub-steps.

[0028] One type of pyrolysis is fast pyrolysis, also known as flash pyrolysis in the art. Fast pyrolysis refers to the thermal decomposition of a solid renewable feedstock in the absence of oxygen at a temperature in the range of 350 - 650 °C, such as about 500 °C, and a reaction time of 10 seconds or less, such as 5 seconds or less, such as about 2 seconds. Fast pyrolysis can be carried out, for example, by an autothermal operation, such as in a fluidized bed reactor. The latter is also known as autothermal pyrolysis and is characterized by the use of air, optionally together with an inert gas or recycle gas, as the fluidizing gas, or by using a mixture of air and an inert gas or recycle gas. Thus, the partial oxidation of the pyrolysis compounds produced in the pyrolysis reactor (autothermal reactor) provides energy for the pyrolysis while improving heat transfer. For details on autothermal pyrolysis, reference can be made to, for example, "Heterodoxy in Fast Pyrrosis of Biomass" by Robert Brown: https: / / dx.doi.org / 10.1021 / acs.energyfuels.0c03512 In one embodiment, the pyrolysis is fast pyrolysis, where the fast pyrolysis is suitably carried out in the absence of a catalyst and hydrogen.

[0029] "Intermediate" or "slow" pyrolysis is also suitable for high-N feedstocks and may even be more suitable than fast pyrolysis. One reason is that feedstocks with high N tend to contain more alkali metals, which increases the risk of agglomeration and defluidization.

[0030] Thus, in another embodiment, the pyrolysis step is intermediate pyrolysis, where the vapor residence time is in the range of 10 seconds - 5 minutes, such as in the range of 11 seconds - 3 minutes. As with fast pyrolysis, the temperature is also in the range of 350 - 650 °C, such as about 500 °C. Generally, this pyrolysis is carried out in a pyrolysis reactor for treating different types of waste, where the vapor is burned after the pyrolysis reactor. Typical reactors include: Herreshoff furnace, rotary drum, amaron, CHOREN paddle pyrolysis kiln, screw reactor, and vacuum pyrolysis reactor.

[0031] In another embodiment, the pyrolysis step is slow pyrolysis, where the solid residence time is in the range of 5 minutes to 2 hours, such as 10 minutes to 1 hour. The temperature is suitably about 300 °C. This pyrolysis has a high char yield, and the char can be used as fertilizer or char coal; the pyrolysis still produces some gas and renewable crude oil, and if the carbon is used as fertilizer, the GHG of the final bio-oil can exceed 100%, so it is carbon negative. Typical reactors are screw reactors (but with different residence times from medium pyrolysis), fixed bed reactors, kilns, lambiotte SIFIC / CISR distillers, Lurgi processes, wagon reactors, and carbo twin resorts.

[0032] Hydrothermal liquefaction (HTL) involves the reaction of biomass or organic materials under hydrothermal conditions in the presence of water or other solvents, effectively carried out in the temperature range of 250 °C to 450 °C and at a pressure of about 100 - 350 bar. Under these conditions, water remains in a liquid or relatively dense supercritical state. Due to the requirement for a wet reaction environment, HTL is particularly suitable for wet feedstocks as no drying is required. During the HTL process, the organic materials undergo a series of depolymerization reactions including hydrolysis, dehydration, and decarboxylation to form water-soluble intermediates, and undergo repolymerization reactions including various condensation mechanisms to form water-insoluble products including renewable crude oil and coke. Other products are gases, usually mainly CO2, but with different contents of H2, CH4, and CO depending on the biomass and reaction conditions, as well as an aqueous phase containing soluble organic matter, which is mainly in the form of alcohols, acids, and phenols (for lignocellulose).

[0033] Thus, suitably, the thermal decomposition step can be:

[0034] - Pyrolysis, such as fast, medium, or slow pyrolysis, to produce a pyrolysis oil stream; or

[0035] - Hydrothermal liquefaction (HTL) to produce an HTL oil stream.

[0036] In one aspect of the method according to the present invention, the solid renewable feedstock is:

[0037] - Lignocellulosic biomass, which includes: wood products, forestry waste, and agricultural residues; and / or

[0038] - Municipal waste, especially the organic part thereof, where municipal waste is defined as the raw material of materials containing items discarded by the public, such as the mixed municipal waste specified in Part A of Annex IX of EU Directive 2018 / 2001 (RED II).

[0039] The term "renewable" shall be construed as not including fossil crude oil, but including recycled waste of fossil origin, such as plastic waste.

[0040] Any combination as described above is also contemplated.

[0041] As used herein, the term "lignocellulosic biomass" refers to biomass that contains cellulose, hemicellulose, and optionally lignin. The lignin or a majority thereof may have been removed, for example, by a previous bleaching step. The lignocellulosic biomass is suitably forestry waste and / or agricultural residues, and includes biomass derived from plants, said plants including grasses such as natural grass (grass from a natural landscape), wheat such as wheat straw, oats, rye, reeds, bamboo, sugarcane or sugarcane derivatives such as bagasse, corn, and other grains.

[0042] In one embodiment, the method further includes passing a stable liquid oil stream through a hydrodeoxygenation (HDO), hydrodenitrogenation (HDN), or hydrodesulfurization (HDS) step, suitably, where HDO is carried out at a higher temperature than the previous step that formed the stable liquid oil stream.

[0043] Thereby, any organic nitrogen present in the stable pyrolysis oil stream is removed, and a hydrotreated stream is produced, which can be further processed to produce hydrocarbon products having boiling points within the range of transportation fuels, such as diesel, jet fuel, and naphtha. During the hydrotreating of renewable feedstocks or liquid oils, oxygen is mainly removed in the form of H2O, thereby producing a paraffin fuel composed of paraffins having the same number of carbon atoms as the triglyceride backbone. This is referred to as the hydrodeoxygenation (HDO) pathway. Oxygen can also be removed via the dicarboxylic acid (DCO) pathway, which produces CO2 instead of H2O: HDO pathway: C 17 H 34 COOH + 3.5H2 <-> C I8 H 38 + H2O; decarboxylation pathway: C 17 H 34 COOH + 0.5H2 <-> C 17 H 36 + CO2.

[0044] Materials having catalytic activity in hydrotreating (such as HDO) generally include active metals (sulfided base metals, such as nickel, cobalt, tungsten, and / or molybdenum, but may also be elemental noble metals, such as platinum and / or palladium) and heat-resistant supports (such as alumina, silica, or titania, or a combination thereof).

[0045] In one embodiment, the method further comprises passing a stable liquid oil stream through one or more metal guards that are active in hydrodemetallization (HDM) and / or hydrodeoxygenation (HDO) prior to the HDO step. Suitable guard beds for at least removing P and Fe are porous materials comprising alumina, the alumina comprising α-alumina, the porous materials comprising one or more metals selected from Co, Mo, Ni, W, and combinations thereof, and the porous materials having a BET surface area of 1 - 110 m 2 / g, suitably also having a total pore volume of 0.50 - 0.80 ml / g measured by mercury porosimetry, and having a pore size distribution (PSD) in which at least 30 vol% of the total pore volume is pores with a radius > 400 Å, suitably pores with a radius > 500 Å, e.g., pores with a radius of up to 5000 Å; as disclosed, for example, in co-pending patent application PCT / EP2021 / 068656. Another suitable guard bed is a catalyst comprising molybdenum supported on alumina, i.e., a Mo / Al2O3 catalyst. Another suitable catalyst is a catalyst having demetallization activity and moderate hydrodesulfurization activity, such as a NiMo catalyst, e.g., in which the metal content is Mo: 6.0 wt%, Ni: 1.8 wt%.

[0046] As is well known in the art, hydrodemetallization (HDM) refers to a pretreatment by which organically bound metals are deposited in the form of sulfides or oxides. It should be understood that although the reaction is similar for hydrodesulfurization (HDS), the heteroatom (S) is removed as gaseous H2S.

[0047] Examples

[0048] Overview

[0049] Oils derived from sewage sludge and other nitrogen-rich feedstocks have a high nitrogen content (> 1 wt%). These oils have higher thermal stability than fast pyrolysis oils but still require stabilization treatment before being heated to 300 °C. In this study, a NiMoS / Al2O3 (Mo: 6.0 wt%, Ni: 1.8 wt%) catalyst was used to stabilize an oil with a nitrogen content of 9 wt%, operating at LHSV: 0.25 - 0.5 h -1 、20 - 120 barg and 190 - 220 °C. The oil was successfully stabilized and further hydrotreated, which reduced the nitrogen content to 0.17 wt%.

[0050] Catalyst, Feedstock, and Test Conditions

[0051] The oil composition is shown in Table 1. The oil was produced from sewage sludge, which is the reason for its high nitrogen content (9.0 wt%).

[0052] Table 1. Oil Composition

[0053] Analysis Method H (wt%) D 7171 8.64 S (wt%) D 7039 1.15 N (wt%) D 5373Mod 9.0 O (wt%) D 5373Mod 5.6 Water (wt%) 1033, Karl Fischer 3.04 SG60 / 60°F D 4052 0.9886 MCR (wt%) D 4530 9.81 Carbonyl concentration E 3146 0.8

[0054] Three tests were conducted in two once-through trickled-bed reactor systems (reactors R1 and R2 operating in series), using 100% hydrogen as the treatment gas. The catalyst was diluted with carborundum and loaded into an isothermal stainless-steel tubular reactor. A total volume of 230 mL was used in each test. The catalyst was activated before the test. Samples of the gas and liquid products were taken and analyzed after reaching line-out under each condition. An overview of the test conditions is shown in Table 2.

[0055] Table 2. Overview of catalysts and test conditions (total LHSV: 0.25 h -1 , H2 / oil: 4000 Nl / l)

[0056] Test # Catalyst, R1 Catalyst, R2 T R2 (°C) T R2 (°C) P (barg) 1 A C 300 340 120 2 B B 190-220 190-220 20 3 B C 220 100-360 120

[0057] Catalyst A is a protective catalyst with medium HDS / HDO / HDN activity. Mo: 6.2 wt%, Ni: 1.6 wt%, P: 1.2 wt%

[0058] Catalyst B is a protective catalyst with medium HDS / HDO / HDN activity. Mo: 6.0 wt%, Ni: 1.8 wt%

[0059] Catalyst C is a high-activity HDO / HDN / HDS catalyst. Mo: 19.7 wt%, Ni: 3.6 wt%, P: 2.0 wt%.

[0060] Catalysts, feedstock, and test conditions

[0061] In the first test, assuming the oil was thermally stable, the first reactor was loaded with HDM catalyst, but the inlet of R1 became blocked after 167 hours. As shown in Table 3, the liquid product from the first test contained 2.6 wt% nitrogen. The purpose of the second test was to examine whether the oil was stable at 20 bar, 190 °C, and 220 °C. The test was conducted for 431 hours, and no pressure drop was observed inside the reactor. As shown in Table 3, the MCR decreased to 3.80 - 3.96 wt%, compared with 9.81 wt% in the feed, indicating that the product had higher thermal stability than the feed. The nitrogen, sulfur, and oxygen contents also decreased to 8.3 - 8.8 wt%, 0.49 - 0.60 wt%, and 4.4 - 4.9 wt% respectively, while the hydrogen content increased to 8.85 - 9.00 wt%, thus indicating another characteristic of the stable reactor is that it removes some heteroatoms while hydrogenating the oil.

[0062] In the third pilot plant test, the pressure was increased to 120 bar. Under the first condition, the temperature in the first reactor was 220 °C, while the temperature in the second reactor was 100 °C. Therefore, it was considered that the catalyst in the second reactor was inactive at this temperature. Under this condition, according to ASTM D 4530 test, the product had a microcarbon residue (MCR) of 2.36 wt%, while the nitrogen was reduced to 7.6 wt%. When the temperature was increased to 340 °C in Condition 2 and to 360 °C in Condition 3, the nitrogen content was reduced to 1.3 wt% and 0.17 wt% respectively, while the MCR was reduced to below <0.05 wt% and the oxygen content was reduced to below 1 wt%.

[0063] Table 3. Process conditions and product composition.

[0064]

[0065]

[0066] Although the present invention has been described with reference to multiple embodiments and examples, those skilled in the art can freely combine the embodiments and aspects as needed. The full scope of the present invention is defined in the appended patent claims. All references cited herein are incorporated herein by reference.

Claims

1. A method for hydrotreating a nitrogen-rich liquid oil stream, the nitrogen-rich liquid oil stream containing at least 0.5 wt% nitrogen and 0.5 mmol / g to 1.13 mmol / g carbonyls, by continuous operation in a fixed bed reactor, in the presence of a catalyst, at a temperature of 80 - 250 °C, a pressure of 10 - 200 barg, and a liquid hourly space velocity (LHSV) of 0.1 - 6 h -1 conditions, reacting the nitrogen-rich liquid oil stream with hydrogen to form a stable liquid oil stream.

2. The method according to claim 1, wherein the ratio of hydrogen to liquid oil in the method is 100 - 8000 NL / L, such as 2000 - 5000 NL / L, and the ratio of hydrogen to liquid oil is defined as the volume ratio of hydrogen to the liquid oil stream.

3. The method according to any one of the preceding claims, wherein the liquid oil stream contains at least 2 wt% of nitrogen (N), such as at least 5 wt% of N.

4. The method according to any one of the preceding claims, wherein the liquid oil stream contains at least 0.5 wt% of oxygen (O), such as at least 2 wt% of O, or at least 4 wt% of O.

5. The method according to any one of the preceding claims, wherein the microcarbon residue (MCR) of the liquid oil stream as measured according to ASTM D 4530 is 5 - 20 wt%, such as 5 - 15 wt%.

6. The method according to any one of the preceding claims, wherein the microcarbon residue (MCR) of the stable liquid oil stream as measured according to ASTM D 4530 is 5 wt% or less, such as 4.5 wt% or less.

7. The method according to any one of the preceding claims, wherein the liquid oil stream is an oil stream derived from a thermochemical decomposition process such as pyrolysis or hydrothermal liquefaction.

8. The method according to any one of the preceding claims, wherein the temperature is 180 - 220 °C, such as 190 - 200 °C; the pressure is 80 - 175 barg, such as 150 barg; the LHSV is 0.2 - 4.0 h -1 , such as 0.2 - 0.2 h -1 , or 0.8 - 1.0 h -1 , such as 0.9 h -1 .

9. The method according to any one of claims 1 - 7, wherein the temperature is 180 - 220 °C, such as 190 - 200 °C; the pressure is 15 - 80 barg, such as 50 barg; the LHSV is 0.2 - 4.0 h -1 , such as 0.2 - 2 h -1 , or 0.8 - 1.0 h -1 , such as 0.9 h -1 .

10. The method according to any one of the preceding claims, wherein the catalyst is a supported catalyst, and based on the total weight of the catalyst, its Mo content is 2 - 30 wt%, and the optional P content is 0 - 3 wt%.

11. The method according to claim 10, wherein the carrier is selected from alumina, silica, titanium dioxide, and combinations thereof; optionally combined with a molecular sieve having a topological structure of MFI, BEA, or FAU.

12. The method according to any one of the preceding claims, wherein the catalyst is Ni - based, Mo - based, CoMo - based, NiMo - based, W - based, NiW - based, or Ru - based, optionally in a sulfided or reduced form.

13. The method according to any one of the preceding claims, which further comprises a previous step of thermally decomposing a solid renewable raw material to produce the liquid oil stream.

14. The method according to claim 13, wherein the thermal decomposition step is: - Pyrolysis, such as medium - rate pyrolysis or slow pyrolysis, to produce a pyrolysis oil stream; or - Hydrothermal liquefaction (HTL) to produce an HTL oil stream.

15. The method according to any one of claims 13 - 14, wherein the solid renewable raw material is: - Lignocellulosic biomass, which includes: wood Articles, forestry wastes, and agricultural residues; and / or - Municipal waste, especially the organic part thereof, wherein municipal waste is defined as a raw material of a material containing items discarded by the public, such as the mixed municipal waste specified in Part A of Annex IX of EU Directive 2018 / 2001 (RED II).

16. The method according to any one of claims 1 - 15, further comprising passing a stable liquid oil stream through a hydrodeoxygenation (HDO), hydrodenitrogenation (HDN), or hydrodesulfurization (HDS) step, suitably wherein the HDO is carried out at a higher temperature than the previous step in which the stable liquid oil stream is formed.

17. The method according to claim 16, further comprising passing the stable liquid oil stream through one or more metal guards that are active in hydrodemetallization (HDM) and / or hydrodeoxygenation (HDO) prior to the HDO step.

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