Preparation method and device of biochar-based catalyst for deoxidation and upgrading of bio-oil suspended bed and integrated equipment

Abstract

The invention belongs to the technical field of resource carbon neutralization, and discloses a preparation method of a biochar-based catalyst for deoxidation and quality improvement of a bio-oil suspended bed, which comprises the following steps: carrying out rapid pyrolytic reaction on biomass to obtain bio-oil, biochar and non-condensable gas A; the non-condensable gas A is used for carrying out a first-stage activation reaction on the biochar to construct micropores, and meanwhile, non-condensable gas B is generated; performing a second-stage activation reaction on the charcoal rich in micropores by using air to construct mesopores; the obtained hierarchical pore biochar rich in micropores and mesopores is subjected to crushing cyclone screening, and biochar powder is obtained; loading active metal on the charcoal powder by adopting an impregnation method to obtain an unreduced charcoal-based catalyst; and carrying out reduction treatment by using the non-condensable gas B. The invention also provides a preparation device of the biochar-based catalyst for deoxidation and quality improvement of the bio-oil suspended bed, and integrated equipment comprising the device. The biochar-based catalyst prepared by the invention is suitable for suspended bed hydrogenation reaction, the catalyst can be continuously added and discharged on line, and long-period operation is ensured.

Description

Technical Field

[0001] This invention belongs to the field of resource carbon neutrality technology, and relates to the emerging field of biomass zero-carbon fuels. Specifically, it relates to the preparation method, apparatus and integrated equipment for biochar-based catalysts for deoxygenation and upgrading of bio-oil suspension beds. Background Technology

[0002] Biomass, as the only carbon-containing resource among renewable energy sources that can be directly converted into liquid fuels, is recognized as the most promising renewable energy source. Producing liquid fuels from biomass materials through whole-component pyrolysis is of practical significance. However, bio-oil obtained through rapid pyrolysis does not reach thermodynamic equilibrium, resulting in unstable physicochemical properties. This is mainly manifested in the viscosity of bio-oil gradually increasing with storage time and temperature, high oxygen content (20-40 wt%), low pH, and low calorific value. Furthermore, it leads to immiscibility with fossil hydrocarbon fuels, limiting its application. Therefore, catalytic hydrogenation upgrading of bio-oil is particularly important, primarily to reduce the oxygen content of the pyrolysis oil so that it can be used in transportation fuels (gasoline, diesel, aviation kerosene) and the energy sector.

[0003] In the hydrodeoxygenation and upgrading process of bio-oil, some oxygen-containing groups, CO and C=O, are prone to condensation reactions during heating, leading to catalyst coking and deactivation. Furthermore, the high water content of bio-oil easily reduces the structural stability of some solid acid catalysts, making them susceptible to coking and deactivation. Therefore, the properties of the catalyst significantly affect the activity and stability of the hydrodeoxygenation reaction, making it a crucial element in the bio-oil deoxygenation and upgrading process. Currently, various heterogeneous catalysts have been developed both domestically and internationally for bio-oil hydrodeoxygenation via cyclohydrogenation, dehydroxylation, and demethoxylation pathways. Among these, carbon-based materials, due to their excellent pore structure which facilitates mass transfer, are widely used as supports for hydrodeoxygenation and upgrading catalysts.

[0004] CN111036266A discloses a method for preparing a nitrogen-doped carbon catalyst and its application in the hydrogenation of bio-oil. This catalyst utilizes the pyrolysis activation of biomass waste to dope nitrogen elements and anchor active metals, enabling highly selective hydrogenation of phenol to cyclohexanone. Biswas et al. (Bioresource Technology, 2021, 17-18) prepared a biochar-derived activated carbon (AC) supported metal catalyst Ni-Co / AC, which promoted the catalytic depolymerization of lignin macromolecules to produce monomeric phenolic compounds. Liu et al. (Energy & Fuels, 2019, 33) developed an activated carbon supported molybdenum carbide catalyst Mo2C / ABC and used it for the hydrodeoxygenation (HDO) evaluation of 4-methylphenol, demonstrating excellent deoxygenation performance. All of the above catalyst preparation methods use biomass-derived model compounds as substrates and do not investigate the hydrodeoxygenation performance of all components from biomass pyrolysis. Bio-oil has a complex composition, encompassing hundreds of components, making it easy to overlook certain aspects.

[0005] CN110776949A discloses a method and apparatus for hydrodesulfurization of bio-oil. This invention involves mixing bio-oil, a catalyst, and a hydrogen donor for reaction, wherein the catalyst is a noble metal-supported activated carbon catalyst. Shu et al. (RenewableEnergy, 2022) proposed a novel bifunctional catalyst coupled with different Ru-based biochar catalysts and silicotungstic acid (HSiW) for the hydrodeoxygenation of lignin-derived phenolic compounds, exhibiting superior hydrodeoxygenation performance compared to other Ru biochar catalysts and commercial Ru / C catalysts. Generally, noble metal catalysts exhibit excellent catalytic performance due to their high activity; however, due to the high cost of noble metals and their susceptibility to poisoning and deactivation in complex bio-oil systems, they are not suitable for industrial application.

[0006] CN108671947A discloses a Ni2P / reduced graphene oxide catalyst for the hydrodeoxygenation reaction of bio-oil and its preparation method. This catalyst uses reduced graphene oxide as a support to load the active component Ni2P, and it exhibits high selectivity for toluene in the reaction system of benzaldehyde hydrodeoxygenation to toluene. Additionally, Dongil et al. (RSC Advances, 2016, 6) prepared a nickel-supported catalyst Ni-Cu / CNT using carbon nanotubes (CNTs) as a support and evaluated its catalytic effect on the hydrodeoxygenation reaction of guaiacol. Using graphene and activated carbon nanotubes as catalyst supports is costly, posing a significant obstacle to the industrial application of bio-oil hydrodeoxygenation to produce high-value fuels.

[0007] In summary, previously developed catalysts for the hydrodeoxygenation and upgrading of bio-oils and their derivatives either use a single model compound as a substrate or rely on expensive precious metals or carbon materials such as graphene as supports. These catalysts suffer from disadvantages such as incomplete evaluation of bio-oil catalytic performance, high cost, and short lifespan, making it difficult to meet the demands of large-scale industrial catalyst production. Some progress has been made in developing catalysts using inexpensive biomass as a carbon source. The core issues mainly concern the activation of biochar and the increase of reactive sites. For example, CN112980476A discloses a method for the targeted production of aromatic-rich bio-oil and hydrogen-rich biomass gas, providing a biochar catalyst prepared by pre-impregnation and re-pyrolysis of chestnut shells with phosphoric acid for biomass catalytic pyrolysis to produce oil and gas. CN113117677A discloses a catalyst preparation method using precipitation to load inexpensive transition metals onto fruit shell biochar for biomass catalytic pyrolysis to produce oil. CN112063400A provides an integrated method for producing carbon-based composite materials from straw-based catalytic pyrolysis, which uses external CO2 or water vapor to activate biochar, which is then used in the processing of biochar / polymer composite materials. However, none of these methods utilize the non-condensable gases from biomass pyrolysis to activate biochar, construct a micro-mesoporous structure suitable for multi-component bio-oil reactions, or utilize the reducing gas after metal impregnation of the biochar carrier. Furthermore, they lack an integrated approach to applying this catalyst to the catalytic hydrodeoxygenation and upgrading of bio-oil produced from biomass pyrolysis.

[0008] Furthermore, compared to fluidized bed hydrogenation, suspension hydrogenation technology uses less catalyst and allows for continuous addition and removal of the catalyst along with the reaction stream, eliminating the need for frequent high and low pressure alternations and significantly improving equipment safety. Therefore, suspension bed reactors are more suitable for processing oils prone to coking. In the processes of residue hydrogenation (oxygen content below ~12%) and direct coal liquefaction (oxygen content below ~10%), due to the high residual carbon content of residue oil and coal powder particles, suspension bed catalysts in residue hydrogenation and direct coal liquefaction are often used as raw coke or coke-carrying particles. To achieve low costs, mineral powders (with uncontrollable and limited pore structure and low metal content) are often used, and the catalyst is discarded after a single use. For bio-oil (oxygen content ~40%), the focus is on maximizing the utilization of green carbon in biomass and minimizing coking, while also requiring deep deoxygenation and high efficiency. Therefore, the catalyst needs to possess the advantages of low cost, multi-level pore structure, and high metal content, which is completely different from the focus of residue oil and direct coal liquefaction catalysts.

[0009] Therefore, this study aims to develop a biochar-based catalyst preparation technology for bio-oil suspension bed deoxygenation and upgrading. This technology fully utilizes the controllable preparation and screening of multi-level porous biochar non-precious metal supported catalysts that meet the requirements of bio-oil hydrodeoxygenation and upgrading, demonstrating significant application value in the green and low-carbon field. Preliminary calculations show that the integrated biomass pyrolysis-to-oil and biochar production strategy reduces CO2 emissions by 66% compared to petroleum-based products. Summary of the Invention

[0010] The purpose of this invention is to address the technical problems existing in the prior art by providing a device and method for preparing biochar-based catalysts for deoxygenation and upgrading of bio-oil suspension beds. The biochar-based catalysts are prepared from the condensate gas produced by biomass pyrolysis and have the advantages of being inexpensive, readily available, and having stable activity.

[0011] Another objective of this invention is to provide a set of bio-oil and biochar-based catalysts for co-production, and to use the biochar-based catalysts in the deoxygenation and upgrading reaction of suspended bed bio-oil.

[0012] To achieve the above objectives, the present invention adopts the following technical solutions.

[0013] This invention provides a method for preparing a biochar-based catalyst for deoxygenation and upgrading of bio-oil suspension beds, comprising the following steps: S1 involves rapid pyrolysis of biomass to produce bio-oil, biochar, and non-condensable gas A. S2 utilizes non-condensable gas A to perform a first-stage activation reaction on biochar to construct micropores, thereby obtaining microporous biochar and simultaneously generating non-condensable gas B; the non-condensable gas B contains H2 and CO. S3 utilizes air to perform a second-stage activation reaction on microporous biochar to construct mesopores, resulting in multi-level porous biochar rich in micropores and mesopores. S4 The obtained multi-level porous biochar rich in micropores and mesopores is ground and sifted by hydrocyclone sieving to obtain biochar powder with a particle size range of 20~300 μm. S5 uses an impregnation method to load active metals onto biochar powder to obtain an unreduced biochar-based catalyst. S6 uses the non-condensable gas B obtained in step S2 to reduce the unreduced biochar-based catalyst to obtain the final biochar-based catalyst.

[0014] In step S1 above, the biomass is one of the following: fruit shells (coconut shells, walnut shells, apricot shells, etc.), woody materials (bamboo waste, wood chips, etc.), straw (corn stalks, cotton stalks), industrial by-products (such as distiller's grains), and agricultural livestock and poultry manure, or a combination of at least two of them.

[0015] The above-mentioned rapid pyrolysis reaction conditions are: pyrolysis temperature of 400~700℃, heating rate of 1000~5000 K / s, and pyrolysis time of 1~30 s. The products obtained from the rapid pyrolysis reaction of biomass are cooled to obtain bio-oil, biochar, and non-condensable gas A. In a preferred embodiment, the products obtained from the rapid pyrolysis reaction of biomass are cooled to below 40℃ to obtain bio-oil, biochar, and non-condensable gas A. The composition of non-condensable gas A produced by the pyrolysis reaction varies depending on the biomass raw material, mainly including water vapor and CO2, with small amounts of CO and light hydrocarbons (including methane, ethane, ethylene, propane, and butane, etc.). The composition of non-condensable gas A is not limited here; non-condensable gas A mainly serves as the activation atmosphere for the first stage of biochar activation in step S2. As long as biomass is used as the raw material, the non-condensable gas A obtained according to the pyrolysis reaction conditions of this invention can meet the requirements.

[0016] The aforementioned rapid pyrolysis reaction can also use inert gases such as nitrogen as carrier gases.

[0017] In step S2 above, it was found that non-condensable gas A can be used as the activation atmosphere for the first stage of biochar activation. The activation reaction conditions for the first stage are: activation temperature of 800~900℃, activation atmosphere of non-condensable gas A, heating rate of 3℃ / min~10℃ / min, and activation time of 0.5~4 h.

[0018] In step S3 above, the conditions for the second-stage activation reaction are as follows: the activation temperature is 250~350℃, the activation atmosphere is air, and the activation time is 0.5~4 h. After the activation reaction, the resulting hierarchical porous biochar rich in micropores and mesopores has a micropore volume of 40~50% and a mesopore volume of 50~60%.

[0019] When the first and second activation processes are carried out separately, the heating rate during the second activation process is 3℃ / min ~ 10℃ / min; when the first and second activation processes are carried out continuously, after the first activation process is completed, the temperature can be directly reduced to the second activation temperature, and then the second activation gas can be introduced to activate the biochar in the second stage.

[0020] In step S4 above, the grinding particle size range of the multi-level porous biochar during grinding and cyclone screening is 20~300μm, preferably 70~150μm.

[0021] In step S5 above, the active metal is at least two of the following: Co, Ni, W, Mo, Cr, Fe, Nb, Zr, Ti, and Ce. The active metal is loaded onto the surface of the biochar powder pores using an equal-volume impregnation method after measuring its pore volume. The biochar powder is immersed in an active metal salt solution and ultrasonically dispersed for 0.5–2 h, followed by drying and calcination to obtain the biochar-based catalyst loaded with the active metal. The calcination process involves calcining the biochar powder loaded with the active metal at 300–550 °C for 1–4 h under an inert gas environment to obtain the unreduced biochar-based catalyst. The inert gas is one of nitrogen, argon, or helium.

[0022] In step S6 above, it was found that the non-condensable gas B obtained in step S2 can be used as a reducing gas for the biochar-based catalyst, reducing the unreduced biochar-based catalyst at 300-500℃ to obtain the final biochar-based catalyst; the reduction treatment time is preferably 1-4 hours. The mass fraction of active metal loaded on the biochar powder support is 2-20%. The water vapor and CO2 generated during the reduction treatment can also be returned to step S2 and used to continue the first-stage activation reaction of the biochar.

[0023] This invention also discloses the application of the biochar-based catalyst prepared by the above method in the deoxygenation and upgrading of bio-oil. The prepared biochar-based catalyst is used in the deoxygenation and upgrading reaction of the bio-oil obtained in step S1. Specifically, a suspended bed reactor is used at 300-350°C and 10-15 MPa to perform a hydrodeoxygenation and upgrading reaction on the bio-oil based on the biochar-based catalyst to obtain the target product oil phase. Reaction conditions: space velocity 0.2-4 h⁻¹. -1 The hydrogen-to-oil ratio is 600-1200; the target product has an oil phase deoxygenation rate of over 70% and an increase in calorific value of at least 20-200%.

[0024] The present invention also provides a biochar-based catalyst preparation device for deoxygenation and upgrading of bio-oil suspension bed, which includes a pyrolysis unit, a carbon activation unit, a grinding and cyclone screening unit, an active metal loading unit and a catalyst reduction unit; The pyrolysis unit is used to pyrolyze biomass to obtain bio-oil, biochar, and non-condensable gas A. The biochar activation unit is used to activate biochar to obtain multi-level porous biochar rich in micropores and mesopores. The grinding and cyclone screening unit grinds and sieving the obtained multi-level porous biochar rich in micropores and mesopores to obtain biochar powder. The active metal supporting unit includes a metal impregnation subunit and a calcination subunit; the metal impregnation subunit is used to impregnate biochar powder in an active metal salt solution and load the active metal salt onto the biochar powder; and then the calcination subunit is used to calcine to obtain an unreduced biochar-based catalyst. The catalyst reduction unit is used to reduce the unreduced biochar-based catalyst to obtain the final biochar-based catalyst.

[0025] In one possible implementation, the pyrolysis unit includes a pyrolysis reactor, a biochar storage unit, an oil collection and condensation tank, an oil storage tank, and a gas storage tank. The pyrolysis reactor is used to pyrolyze biomass to obtain pyrolysis oil and gas and biochar; the biochar obtained from the reaction is transported to the biochar storage unit via pipeline; the oil collection and condensation tank is used to cool the pyrolysis oil and gas to obtain bio-oil and non-condensable gas A; the bio-oil can be directly collected in the oil collection and condensation tank, and the non-condensable gas A is stored in the gas collection tank via pipeline.

[0026] In one possible implementation, the biochar activation unit employs a conventional activated carbon activation furnace. The furnace uses a three-way valve to switch between two gas sources: non-condensable gas A used in the first activation stage and air used in the second activation stage. The first activation stage utilizes non-condensable gas A to activate the biochar, constructing micropores and resulting in microporous biochar, while simultaneously generating non-condensable gas B, which contains H2 and CO. The second activation stage utilizes air to activate the microporous biochar, constructing mesopores and resulting in multi-level porous biochar rich in micropores and mesopores.

[0027] In one possible implementation, the grinding cyclone screening unit employs a conventional cyclone separator already disclosed in the art.

[0028] In one possible implementation, the metal impregnation subunit uses a conventional impregnation container. The calcination subunit uses a conventional sintering furnace; the inlet of the calcination subunit is connected to an inert gas supply device.

[0029] In one possible implementation, the catalyst reduction unit is a rotary reduction furnace; the inlet of the catalyst reduction unit is connected to the outlet of the biochar activation unit, using the non-condensable gas B generated in the biochar activation unit as the reducing gas for the biochar-based catalyst, thereby achieving full utilization of resources and reducing energy consumption. The water vapor and CO2 generated during the reduction process can also be returned to the biochar activation unit 2 for further activation of the biochar.

[0030] The present invention also provides an integrated device, which includes a biochar-based catalyst preparation apparatus and a suspended bed reactor; the suspended bed reactor is used to perform a hydrodeoxygenation and upgrading reaction on bio-oil to obtain the target product oil phase.

[0031] In one possible implementation, the suspended bed reactor employs a conventional structure already disclosed in the art, see CN219252552U, which discloses a suspended bed hydrogenation reaction system for producing biodiesel from biomass residue oil.

[0032] Compared with the prior art, the present invention has the following beneficial effects: (1) This invention uses biochar produced during the preparation of bio-oil as raw material, and uses non-condensable gases H2O and CO2 generated by the rapid pyrolysis of biomass for carbon activation. Then, it uses air for secondary activation to obtain multi-level biochar rich in micropores and mesopores. It is used as a carrier, and bimetals are used as synergistic active centers to prepare biochar-based catalysts. Then, the reducing gases H2 and CO in the non-condensable gases are used to reduce the biochar-based catalysts. The preparation process is easy to control and the utilization efficiency of all components of biomass is high. (2) The biochar-based catalyst prepared by the present invention can be directly used for deoxygenation and upgrading of bio-oil; the present invention can realize the micro-mesoporous channel regulation of biochar powder, promote heat and mass transfer, improve the water resistance of the catalyst, and thus improve the hydrodeoxygenation efficiency and stability. (3) The CO2 generated after reduction in this invention can also be used for carbon activation, thus making full use of resources in the preparation process; (4) The biochar-based catalyst prepared by the present invention has low bulk density, large specific surface area, fast reaction mass transfer, and anti-coking and high water resistance properties, which is beneficial to improving the structural stability of the bio-oil upgrading catalyst. (5) The biochar-based catalyst prepared by the present invention is suitable for suspended bed hydrogenation reaction; moreover, the biochar-based catalyst can be continuously added and discharged online to ensure long-term operation. Attached Figure Description

[0033] Figure 1 This is a schematic diagram of the integrated device provided by the present invention; Figure 2 The above are the SEM test results of the biochar-based catalyst prepared in Example 1; Figure 3 A schematic diagram of the specific surface area (a) and pore size distribution (b) of the biochar-based catalyst prepared in Example 1; Figure 4 The results of the original components test of the bio-oil in Example 4 (GC-MS); Figure 5 The results of GC-MS analysis of the components of the deoxygenated and upgraded liquid after catalytic deoxygenation of bio-oil using the biochar-based catalyst in Example 4 are shown. Components, parts, and numbers shown in the diagram: 1-Pyrolysis unit, 11-Pyrolysis reactor, 12-Biochar storage tank, 13-Oil collection and condensation tank, 14-Oil storage tank, 15-Gas storage tank; 2-Biochar activation unit; 3-Grinding and cyclone screening unit; 4-Active metal supported unit; 41-Metal impregnation sub-unit; 42-Sintering sub-unit; 5-Catalyst reduction unit; 6-Suspended bed reactor. Detailed Implementation

[0034] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are part of the present invention.

[0035] Example A

[0036] This invention provides a device for preparing a biochar-based catalyst for deoxygenation and upgrading of bio-oil in a suspension bed, such as... Figure 1 As shown, it includes a pyrolysis unit 1, a biochar activation unit 2, a grinding and cyclone screening unit 3, an active metal loading unit 4, and a catalyst reduction unit 5.

[0037] The aforementioned pyrolysis unit 1 is used to perform a pyrolysis reaction on biomass to obtain bio-oil, biochar, and non-condensable gas A. In this embodiment, the pyrolysis unit 1 adopts a conventional structure already disclosed in the art. The pyrolysis unit 1 includes a pyrolysis reactor 11, a biochar storage tank 12, an oil collection and condensation tank 13, an oil storage tank 14, and a gas storage tank 15. The pyrolysis reactor 11 is used to perform a pyrolysis reaction on biomass to obtain pyrolysis oil and gas and biochar. The biochar obtained from the reaction is transported to the biochar storage tank 12 for storage through a pipeline; the pyrolysis oil and gas obtained from the reaction are cooled through the oil collection and condensation tank 13 to obtain bio-oil and non-condensable gas A. The bio-oil can be collected in the oil storage tank 14, and the non-condensable gas A is stored in the gas storage tank 15 through a pipeline.

[0038] The aforementioned biochar activation unit 2 is used to activate biochar to obtain multi-level porous biochar rich in micropores and mesopores. In this embodiment, the biochar activation unit 2 adopts a conventional activated carbon activation furnace. The activation furnace uses a three-way valve to switch between two gas sources: non-condensable gas A used in the first stage activation reaction and air used in the second stage activation reaction. The first stage activation reaction uses non-condensable gas A to perform a first-stage activation reaction on the biochar to construct micropores, obtaining biochar rich in micropores, while simultaneously generating non-condensable gas B, which contains H2 and CO. The second stage activation reaction uses air to perform a second-stage activation reaction on the micropore-rich biochar to construct mesopores, obtaining multi-level porous biochar rich in micropores and mesopores.

[0039] The aforementioned grinding and cyclone screening unit 3 grinds and sieving the obtained multi-level porous biochar rich in micropores and mesopores to obtain biochar powder. In this embodiment, the grinding and cyclone screening unit uses a conventional cyclone separator already disclosed in the art.

[0040] The aforementioned active metal loading unit 4 includes a metal impregnation subunit 41 and a calcination subunit 42. The metal impregnation subunit 41 is used to impregnate biochar powder in an active metal salt solution, thereby loading the active metal salt onto the biochar powder; then, the biochar-based catalyst is obtained by calcination in the calcination subunit 42. In this embodiment, the metal impregnation subunit 41 uses a conventional impregnation container; the calcination subunit 42 uses a conventional sintering furnace; and the inlet of the calcination subunit 42 is connected to an inert gas supply device.

[0041] The catalyst reduction unit 5 described above is used to reduce unreduced biochar-based catalyst to obtain the final biochar-based catalyst. Catalyst reduction unit 5 is a rotary reduction furnace. The inlet of catalyst reduction unit 5 is connected to the outlet of biochar activation unit 2, using the non-condensable gas B generated in the biochar activation unit as the reducing gas for the biochar-based catalyst, thus achieving full utilization of resources and reducing energy consumption. The water vapor and CO2 generated during the reduction process can also be returned to biochar activation unit 2 for further activation of the biochar.

[0042] Example B

[0043] The integrated equipment in this embodiment includes the biochar-based catalyst preparation device provided in Example A, and the suspended bed reactor 6.

[0044] The slurry bed reactor 6 is used for hydrodeoxygenation and upgrading of bio-oil to obtain the target product oil phase. In this embodiment, the slurry bed reactor adopts a conventional structure already disclosed in the art, such as the slurry bed reactor disclosed in patent application CN219252552U.

[0045] In Example A above, the bio-oil in storage tank 14 can be directly transported to the slurry bed reactor 6 via pipeline. The biochar-based catalyst prepared by catalyst reduction unit 5 is directly transported to the slurry bed reactor 6 for hydrodeoxygenation and upgrading of the bio-oil.

[0046] The biomass used in Examples 1-5 below are coconut shells, walnut shells, bamboo waste, corn stalks, and distiller's grains.

[0047] Example 1: Preparation and Application of Ni-Cr / C Catalyst

[0048] The preparation steps of the Ni-Cr / C catalyst provided in this embodiment are as follows:

[0049] S1 involves the rapid pyrolysis of biomass to produce bio-oil, biochar, and non-condensable gas A.

[0050] In this embodiment, waste coconut shell raw materials are washed, dried, and ground, and then added to the pyrolysis reactor of pyrolysis unit 1 for pyrolysis reaction to obtain biochar and pyrolysis oil and gas. The heating rate is set to 1000 K / s, the pyrolysis temperature is 400℃, the residence time is 30s, and the carrier gas is nitrogen. The generated biochar is transported to the biochar storage tank 12 for storage through pipeline. The separated pyrolysis oil and gas enter the oil collection and condensation tank 13 to be cooled to below 40℃. The obtained bio-oil is collected and stored in the oil storage tank 14. The cooled non-condensable gas A enters the gas storage tank 15 through pipeline for storage. Non-condensable gas A mainly includes water vapor and CO2, as well as a small amount of CO and light hydrocarbons (including methane, ethane, ethylene, propane, and butane, etc.).

[0051] S2 utilizes non-condensable gas A to perform a first-stage activation reaction on biochar to construct micropores, resulting in microporous biochar, while simultaneously generating non-condensable gas B; non-condensable gas B contains H2 and CO.

[0052] In this embodiment, the biochar stored in the biochar storage unit 12 is transferred to the biochar activation unit 2 via a conveyor. Non-condensable gas A is introduced as the first stage activation gas. The heating rate is set to 5℃ / min, the biochar activation temperature is 800℃, and the residence time is 1 h to obtain biochar rich in micropores. The generated non-condensable gas B is introduced into the catalyst reduction unit 5. Non-condensable gas B contains H2 and CO.

[0053] S3 utilizes air to perform a second-stage activation reaction on microporous biochar to construct mesopores, resulting in hierarchical porous biochar rich in micropores and mesopores.

[0054] After step S2, once the temperature drops to 350℃, air is introduced as the second activation gas, and the activation time is 1 hour, resulting in activated multi-level porous biochar rich in micropores and mesopores.

[0055] S4 The obtained multi-level porous biochar rich in micropores and mesopores is crushed and sifted to obtain biochar powder.

[0056] In this embodiment, multi-level porous biochar rich in micropores and mesopores is placed into the grinding and cyclone screening unit 3 to obtain biochar powder with a particle size of 20~100μm.

[0057] S5 uses an impregnation method to load active metals onto biochar powder to obtain an unreduced biochar-based catalyst.

[0058] In this embodiment, the pore volume of the biochar powder was measured to be approximately 0.85 cm³. 3Based on the equal-volume impregnation method, in the metal impregnation subunit 41, 4.95 g Ni(NO3)2·6H2O and 3.04 g CrCl3 precursor were added to 10 mL of water and fully dissolved. Then, 10 g of biochar powder was added and ultrasonically dispersed for 0.5 h. The catalyst was then placed in a 60 °C oven and the water was slowly evaporated. The evaporated catalyst was then dried in an 80 °C oven overnight. Then, it was placed in the calcination subunit 42 for calcination at a heating rate of 3 °C / min, a calcination temperature of 500 °C, and a holding time of 3 h. After natural cooling, it was stored to obtain an unreduced Ni-Cr / C catalyst (active component Ni mass fraction of 10% and Cr mass fraction of 5%).

[0059] S6 uses the non-condensable gas B obtained in step S2 to reduce the unreduced biochar-based catalyst to obtain the final biochar-based catalyst.

[0060] In this embodiment, unreduced Ni-Cr / C is placed in the catalyst reduction unit 5, and non-condensable gas B (H2 and CO) from the biochar activation unit 2 is introduced as the reducing gas. The heating rate is set to 5℃ / min, the reduction temperature is 350℃, and the temperature is maintained for 2h. After cooling, the Ni-Cr / C catalyst is obtained.

[0061] The applications of the Ni-Cr / C catalyst are as follows:

[0062] The reduced Ni-Cr / C catalyst prepared above was loaded into the slurry bed reactor 6, and 200 mL of bio-oil from the oil storage tank 14 was added through a pipeline. The heating rate was set to 10 °C / min, and the temperature was raised to 300 °C and maintained. The reaction pressure was adjusted to 10 MPa, the hydrogen-to-oil ratio was set to 800:1, and the reaction volume hourly space velocity was set to 0.4 h⁻¹. -1 After the reaction stabilized, the sample was collected and its composition was analyzed using gas chromatography-mass spectrometry.

[0063] Example 2: Preparation and Application of Co-W / C Catalyst

[0064] The preparation steps of the Co-W / C catalyst provided in this embodiment are as follows:

[0065] S1 involves the rapid pyrolysis of biomass to produce bio-oil, biochar, and non-condensable gas A.

[0066] In this embodiment, the walnut shell raw material is washed, dried, and ground, and then added to the pyrolysis reactor of pyrolysis unit 1 for pyrolysis reaction to obtain biochar and pyrolysis oil and gas. The heating rate is set to 3000 K / s, the pyrolysis temperature is 500℃, the residence time is 20s, and the carrier gas is nitrogen. The generated biochar is transported to the biochar storage tank 12 for storage through pipeline. The separated pyrolysis oil and gas enter the oil collection and condensation tank 13 to be cooled to below 40℃. The obtained bio-oil is collected and stored in the oil storage tank 14. The cooled non-condensable gas A enters the gas storage tank 15 through pipeline for storage. Non-condensable gas A mainly includes water vapor and CO2, as well as a small amount of CO and light hydrocarbons (including methane, ethane, ethylene, propane, and butane, etc.).

[0067] S2 utilizes non-condensable gas A to perform a first-stage activation reaction on biochar to construct micropores, resulting in microporous biochar, while simultaneously generating non-condensable gas B; non-condensable gas B contains H2 and CO.

[0068] In this embodiment, the biochar stored in the biochar storage unit 12 is transferred to the biochar activation unit 2 via a conveyor. Non-condensable gas A is introduced as the first stage activation gas. The heating rate is set to 10℃ / min, the biochar activation temperature is 800℃, and the residence time is 2h to obtain biochar rich in micropores. The generated non-condensable gas B is introduced into the catalyst reduction unit 5. Non-condensable gas B contains H2 and CO.

[0069] S3 utilizes air to perform a second-stage activation reaction on microporous biochar to construct mesopores, resulting in hierarchical porous biochar rich in micropores and mesopores.

[0070] After step S2, when the temperature drops to 350℃, air is introduced as the second activation gas, and the activation time is 1.5h, resulting in activated multi-level porous biochar rich in micropores and mesopores.

[0071] S4 The obtained multi-level porous biochar rich in micropores and mesopores is crushed and sifted to obtain biochar powder.

[0072] In this embodiment, multi-level porous biochar rich in micropores and mesopores is placed into the grinding and cyclone screening unit 3 to obtain biochar powder with a particle size of 50~120μm.

[0073] S5 uses an impregnation method to load active metals onto biochar powder to obtain an unreduced biochar-based catalyst.

[0074] In this embodiment, the pore volume of the biochar powder was measured to be approximately 0.98 cm³. 3 / g, based on the equal volume impregnation method, in the metal impregnation subunit 41, 3.1 g Co(NO3)2·6H2O and 2.78 g (NH4)6W7O are added. 24The 6H2O precursor was added to 10 mL of water and dissolved completely. Then, 10 g of biochar powder was added to the solution and ultrasonically dispersed for 1 h. The solution was then slowly evaporated in a 50 ℃ oven. The evaporated catalyst was dried overnight in an 80 ℃ oven. Then, it was placed in calcination subunit 42 for calcination at a heating rate of 5 ℃ / min, a calcination temperature of 500 ℃, and a holding time of 3 h. After natural cooling, the catalyst was stored to obtain unreduced Co-W / C catalyst (active component Co mass fraction of 10% and W mass fraction of 2%).

[0075] S6 uses the non-condensable gas B obtained in step S2 to reduce the unreduced biochar-based catalyst to obtain the final biochar-based catalyst.

[0076] In this embodiment, the unreduced Co-W / C catalyst was placed in the catalyst reduction unit 5, and non-condensable gas B (H2 and CO) from the biochar activation unit 2 was introduced as the reducing gas. The heating rate was set to 10 ℃ / min, the reduction temperature was 350 ℃, and the temperature was maintained for 2 h. After cooling, the Co-W / C catalyst was obtained.

[0077] The applications of the Co-W / C catalyst are as follows:

[0078] The reduced Co-W / C catalyst prepared above was loaded into the slurry bed reactor 6, and 200 mL of bio-oil from the oil storage tank 14 was added through a pipeline. The heating rate was set to 10 °C / min, and the temperature was raised to 320 °C and maintained. The reaction pressure was adjusted to 13 MPa, the hydrogen-to-oil ratio was set to 600:1, and the volume hourly space velocity was set to 1.0 h⁻¹. -1 After the reaction stabilized, the sample was collected and its composition was analyzed using gas chromatography-mass spectrometry.

[0079] Example 3: Preparation and Application of Ni-Mo / C Catalyst

[0080] The Ni-Mo / C catalyst preparation steps provided in this embodiment are as follows:

[0081] S1 involves the rapid pyrolysis of biomass to produce bio-oil, biochar, and non-condensable gas A.

[0082] In this embodiment, the bamboo waste is washed, dried, and ground, and then added to the pyrolysis reactor of pyrolysis unit 1 for pyrolysis reaction to obtain biochar and pyrolysis oil and gas. The heating rate is set to 4000 K / s, the pyrolysis temperature is 550℃, the residence time is 15s, and the carrier gas is nitrogen. The generated biochar is transported to the biochar storage tank 12 for storage through pipeline. The separated pyrolysis oil and gas enter the oil collection and condensation tank 13 to be cooled to below 40℃. The obtained bio-oil is collected and stored in the oil storage tank 14. The cooled non-condensable gas A enters the gas storage tank 15 through pipeline for storage. Non-condensable gas A mainly includes water vapor and CO2, as well as a small amount of CO and light hydrocarbons (including methane, ethane, ethylene, propane, and butane, etc.).

[0083] S2 utilizes non-condensable gas A to perform a first-stage activation reaction on biochar to construct micropores, resulting in microporous biochar, while simultaneously generating non-condensable gas B; non-condensable gas B contains H2 and CO.

[0084] In this embodiment, the biochar stored in the biochar storage unit 12 is transferred to the biochar activation unit 2 via a conveyor. Non-condensable gas A is introduced as the first stage activation gas. The heating rate is set to 10℃ / min, the biochar activation temperature is 850℃, and the residence time is 3h to obtain biochar rich in micropores. The generated non-condensable gas B is introduced into the catalyst reduction unit 5. Non-condensable gas B contains H2 and CO.

[0085] S3 utilizes air to perform a second-stage activation reaction on microporous biochar to construct mesopores, resulting in hierarchical porous biochar rich in micropores and mesopores.

[0086] After step S2, once the temperature drops to 300℃, air is introduced as the second activation gas, and the activation time is 2 hours, resulting in activated multi-level porous biochar rich in micropores and mesopores.

[0087] S4 The obtained multi-level porous biochar rich in micropores and mesopores is crushed and sifted to obtain biochar powder.

[0088] In this embodiment, multi-level porous biochar rich in micropores and mesopores is placed into the grinding and cyclone screening unit 3 to obtain biochar powder with a particle size of 100~200μm.

[0089] S5 uses an impregnation method to load active metals onto biochar powder to obtain an unreduced biochar-based catalyst.

[0090] In this embodiment, the pore volume of the biochar powder was measured to be approximately 1.05 cm³. 3Based on the equal-volume impregnation method, in the metal impregnation subunit 41, 3.96 g of Ni(NO3)2·6H2O and 2.04 g of (NH4)2MoO4 precursor were added to 10 mL of water and fully dissolved. Then, 10 g of biochar powder was added and ultrasonically dispersed for 1.5 h. The catalyst was then placed in a 60 °C oven and the water was slowly evaporated. The evaporated catalyst was then dried in an 80 °C oven overnight. Then, it was placed in the calcination subunit 42 for calcination at a heating rate of 10 °C / min, a calcination temperature of 500 °C, and a holding time of 3 h. After natural cooling, it was stored to obtain unreduced Ni-Mo / C catalyst (active component Ni mass fraction of 8% and Mo mass fraction of 10%).

[0091] S6 uses the non-condensable gas B obtained in step S2 to reduce the unreduced biochar-based catalyst to obtain the final biochar-based catalyst.

[0092] In this embodiment, unreduced Ni-Mo / C is placed in the catalyst reduction unit 5, and non-condensable gas B (H2 and CO) from the biochar activation unit 2 is introduced as the reducing gas. The heating rate is set to 15 ℃ / min, the reduction temperature is 400 ℃, and the temperature is maintained for 2 h. After cooling, Ni-Mo / C catalyst is obtained.

[0093] The applications of the Ni-Mo / C catalyst are as follows:

[0094] The reduced Ni-Mo / C catalyst prepared above was loaded into the slurry bed reactor 6, and 200 mL of bio-oil from the oil storage tank 14 was added through a pipeline. The heating rate was set to 10 °C / min, and the temperature was raised to 340 °C and maintained. The reaction pressure was adjusted to 14 MPa, the hydrogen-to-oil ratio was set to 900:1, and the reaction volume hourly space velocity was set to 2.0 h⁻¹. -1 After the reaction stabilized, the sample was collected and its composition was analyzed using gas chromatography-mass spectrometry.

[0095] Example 4: Preparation and Application of Co-Nb / C Catalyst

[0096] The preparation steps of the Co-Nb / C catalyst provided in this embodiment are as follows:

[0097] S1 involves the rapid pyrolysis of biomass to produce bio-oil, biochar, and non-condensable gas A.

[0098] In this embodiment, the waste corn stalk raw material is washed, dried, and ground, and then added to the pyrolysis reactor of pyrolysis unit 1 for pyrolysis reaction to obtain biochar and pyrolysis oil gas. The heating rate is set to 4500 K / s, the pyrolysis temperature is 600℃, the residence time is 10s, and the carrier gas is nitrogen. The generated biochar is transported to the biochar storage tank 12 for storage through pipeline. The separated pyrolysis oil gas enters the oil collection and condensation tank 13 to be cooled to below 40℃. The obtained bio-oil is collected and stored in the oil storage tank 14. The cooled non-condensable gas A enters the gas storage tank 15 through pipeline for storage. Non-condensable gas A mainly includes water vapor and CO2, as well as a small amount of CO and light hydrocarbons (including methane, ethane, ethylene, propane, and butane, etc.).

[0099] S2 utilizes non-condensable gas A to perform a first-stage activation reaction on biochar to construct micropores, resulting in microporous biochar, while simultaneously generating non-condensable gas B; non-condensable gas B contains H2 and CO.

[0100] In this embodiment, the biochar stored in the biochar storage unit 12 is transferred to the biochar activation unit 2 via a conveyor. Non-condensable gas A is introduced as the first stage activation gas. The heating rate is set to 10℃ / min, the biochar activation temperature is 900℃, and the residence time is 2h to obtain biochar rich in micropores. The generated non-condensable gas B is introduced into the catalyst reduction unit 5. Non-condensable gas B contains H2 and CO.

[0101] S3 utilizes air to perform a second-stage activation reaction on microporous biochar to construct mesopores, resulting in hierarchical porous biochar rich in micropores and mesopores.

[0102] After step S2, once the temperature drops to 350℃, air is introduced as the second activation gas, and the activation time is 1 hour, resulting in activated multi-level porous biochar rich in micropores and mesopores.

[0103] S4 The obtained multi-level porous biochar rich in micropores and mesopores is crushed and sifted to obtain biochar powder.

[0104] In this embodiment, multi-level porous biochar rich in micropores and mesopores is placed into the grinding and cyclone screening unit 3 to obtain biochar powder with a particle size of 70~150μm.

[0105] S5 uses an impregnation method to load active metals onto biochar powder to obtain an unreduced biochar-based catalyst.

[0106] In this embodiment, the pore volume of the biochar powder was measured to be approximately 1.18 cm³. 3 / g, based on the equal-volume impregnation method, in the metal impregnation subunit 41, 3.1 g Co(NO3)2·6H2O and 2.9 g C are added. 10 H5NbO 20The precursor was added to 10 mL of water and dissolved completely. Then, 10 g of biochar powder was added to the solution and ultrasonically dispersed for 2 h. The solution was then slowly evaporated in a 50 °C oven. The evaporated catalyst was dried overnight in an 80 °C oven. Then, it was placed in calcination subunit 42 for calcination at a heating rate of 10 °C / min, a calcination temperature of 500 °C, and a holding time of 3 h. After natural cooling, the catalyst was stored to obtain unreduced Co-Nb / C catalyst (active component Co mass fraction 10%, Nb mass fraction 5%).

[0107] S6 uses the non-condensable gas B obtained in step S2 to reduce the unreduced biochar-based catalyst to obtain the final biochar-based catalyst.

[0108] In this embodiment, unreduced Co-Nb / C is placed into the catalyst reduction unit 5, and non-condensable gas B (H2 and CO) from the biochar activation unit 2 is introduced as the reducing gas. The heating rate is set to 10℃ / min, the reduction temperature is 450℃, and it is maintained for 2h. After cooling, the Co-Nb / C catalyst is obtained.

[0109] The applications of the Co-Nb / C catalyst are as follows:

[0110] The reduced Co-Nb / C catalyst prepared above was loaded into the slurry bed reactor 6, and 200 mL of bio-oil from the oil storage tank 14 was added through a pipeline. The heating rate was set to 10 °C / min, and the temperature was raised to 300 °C and maintained. The reaction pressure was adjusted to 12 MPa, the hydrogen-to-oil ratio was set to 1000:1, and the reaction volume hourly space velocity was set to 3.0 h⁻¹. -1 After the reaction stabilized, the sample was collected and its composition was analyzed using gas chromatography-mass spectrometry.

[0111] Example 5: Preparation and Application of Ni-Co-Zr / C Catalyst

[0112] The preparation steps of the Ni-Co-Zr / C catalyst provided in this embodiment are as follows:

[0113] S1 involves the rapid pyrolysis of biomass to produce bio-oil, biochar, and non-condensable gas A.

[0114] In this embodiment, the waste distiller's grains are washed, dried, and ground, then added to the pyrolysis reactor of pyrolysis unit 1 for pyrolysis reaction to obtain biochar and pyrolysis oil and gas. The heating rate is set to 5000 K / s, the pyrolysis temperature to 700℃, the residence time to 5s, and the carrier gas to be nitrogen. The generated biochar is transported to the biochar storage tank 12 for storage through a pipeline. The separated pyrolysis oil and gas enter the oil collection and condensation tank 13 to be cooled to below 40℃. The obtained bio-oil is collected and stored in the oil storage tank 14. The cooled non-condensable gas A enters the gas storage tank 15 through a pipeline for storage. Non-condensable gas A mainly includes water vapor and CO2, as well as a small amount of CO and light hydrocarbons (including methane, ethane, ethylene, propane, and butane, etc.).

[0115] S2 utilizes non-condensable gas A to perform a first-stage activation reaction on biochar to construct micropores, resulting in microporous biochar, while simultaneously generating non-condensable gas B; non-condensable gas B contains H2 and CO.

[0116] In this embodiment, the biochar stored in the biochar storage unit 12 is transferred to the biochar activation unit 2 via a conveyor. Non-condensable gas A is introduced as the first stage activation gas. The heating rate is set to 10℃ / min, the biochar activation temperature is 850℃, and the residence time is 2h to obtain biochar rich in micropores. The generated non-condensable gas B is introduced into the catalyst reduction unit 5. Non-condensable gas B contains H2 and CO.

[0117] S3 utilizes air to perform a second-stage activation reaction on microporous biochar to construct mesopores, resulting in hierarchical porous biochar rich in micropores and mesopores.

[0118] After step S2, once the temperature drops to 300 ℃, air is introduced as the second activation gas, and the activation time is 2 hours, resulting in activated multi-level porous biochar rich in micropores and mesopores.

[0119] S4 The obtained multi-level porous biochar rich in micropores and mesopores is crushed and sifted to obtain biochar powder.

[0120] In this embodiment, multi-level porous biochar rich in micropores and mesopores is placed into the grinding and cyclone screening unit 3 to obtain biochar powder with a particle size of 150~300μm.

[0121] S5 uses an impregnation method to load active metals onto biochar powder to obtain an unreduced biochar-based catalyst.

[0122] In this embodiment, the pore volume of the biochar powder was measured to be approximately 1.29 cm³. 3Based on the equal-volume impregnation method, in the metal impregnation subunit 41, 4.95 g Ni(NO3)2·6H2O, 1.55 g Co(NO3)2·6H2O and 1.86 g Zr(NO3)4 precursor were added to 10 mL of water and fully dissolved. Then, 10 g of biochar powder was added and ultrasonically dispersed for 0.5 h. The catalyst was then placed in a 60℃ oven and the water was slowly evaporated. The evaporated catalyst was then dried in an 80℃ oven overnight. Then, it was placed in the calcination subunit 42 for calcination at a heating rate of 10℃ / min, a calcination temperature of 500℃, and a holding time of 3 h. After natural cooling, it was stored to obtain an unreduced Ni-Co-Zr / C catalyst (active components: Ni mass fraction 10%, Co mass fraction 5%, Zr mass fraction 5%).

[0123] S6 uses the non-condensable gas B obtained in step S2 to reduce the unreduced biochar-based catalyst to obtain the final biochar-based catalyst.

[0124] In this embodiment, unreduced Ni-Co-Zr / C is placed into the catalyst reduction unit 5, and non-condensable gas B (H2 and CO) from the biochar activation unit 2 is introduced as the reducing gas. The heating rate is set to 15℃ / min, the reduction temperature is 400℃, and it is maintained for 2h. After cooling, Ni-Co-Zr / C catalyst is obtained.

[0125] The applications of the Ni-Co-Zr / C catalyst are as follows:

[0126] The reduced Ni-Co-Zr / C catalyst prepared above was loaded into the slurry bed reactor 6, and 200 mL of bio-oil from the oil collection and condensation tank 13 was added through a pipeline. The heating rate was set to 10 °C / min, and the temperature was raised to 350 °C and maintained. The reaction pressure was adjusted to 15 MPa, the hydrogen-to-oil ratio was set to 1200:1, and the reaction volume hourly space velocity was set to 4.0 h⁻¹. -1 After the reaction stabilized, the sample was collected and its composition was analyzed using gas chromatography-mass spectrometry.

[0127] The biochar-based catalyst prepared in Example 1 was subjected to SEM testing, and the results are as follows: Figure 2 As shown in the figure, it is clear that the prepared biochar-based catalyst has a microporous-mesoporous structure inside.

[0128] The biochar-based catalysts prepared in Examples 1 to 5 were characterized by BET testing to determine their specific surface area and pore size distribution. The results are as follows: Figure 3 As shown in Table 1.

[0129] Table 1. Specific surface area and pore size distribution of biochar-based catalysts in Examples 1-5

[0130]

[0131] As shown in Table 1, the specific surface area of ​​the biochar-based catalyst obtained under the preparation parameters set in the examples is 900~1300 m². 2 / g, total pore volume 0.80 ~ 1.30 cm³ 3 / g, the biochar-based catalyst is composed of a microporous-mesoporous structure.

[0132] Table 2. Physicochemical properties of the biochar-based catalysts prepared in Examples 1-5 for the deoxygenation and upgrading of bio-oil in a suspension bed.

[0133]

[0134] Table 3. Component distribution of biochar-based catalysts prepared in Examples 1-5 on bio-oil suspension deoxygenation and upgrading products.

[0135]

[0136] From Table 2, Table 3, Figure 4 , Figure 5 It is known that the present invention provides the above-mentioned biochar-based catalyst for hydrodeoxygenation and upgrading of bio-oil in a suspended bed. Under the conditions of 300~350 °C and 10~15 MPa, the deoxygenation rate of bio-oil is as high as 73.2%, the content of alkane and aromatic hydrocarbon components is significantly increased, and the water content, viscosity and acid value of bio-oil that has completed the deoxygenation and upgrading reaction are greatly reduced, while the calorific value is increased.

[0137] The formula for calculating the deoxygenation rate is as follows:

[0138] Deoxygenation rate (%) = .

[0139] Long life test:

[0140] In the application test of the biochar-based catalyst Co-Nb / C in the hydrodeoxygenation and upgrading of bio-oil in a suspended bed, provided in Example 4, after continuous operation for 720 hours at 300℃ and 12MPa, the deoxygenation rate of the bio-oil remained stable at over 70%, and the higher heating value of the product remained at 36MJ / kg. This indicates that the biochar-based catalyst prepared by this invention not only has high activity but is also a very stable supported catalyst. Its long lifespan means reduced catalyst costs and has good application value in practical production.

[0141] Those skilled in the art will recognize that the embodiments described herein are intended to help the reader understand the principles of the invention, and should be understood that the scope of protection of the invention is not limited to such specific statements and embodiments. Those skilled in the art can make various other specific modifications and combinations based on the technical teachings disclosed in this invention without departing from the spirit of the invention, and these modifications and combinations are still within the scope of protection of this invention.

Claims

1. A method for preparing a biochar-based catalyst for deoxygenation and upgrading of bio-oil in a suspension bed, characterized in that, Includes the following steps: S1 involves rapid pyrolysis of biomass to produce bio-oil, biochar, and non-condensable gas A. S2 utilizes non-condensable gas A to perform a first-stage activation reaction on biochar to construct micropores, thereby obtaining microporous biochar and simultaneously generating non-condensable gas B; the non-condensable gas B contains H2 and CO. S3 utilizes air to perform a second-stage activation reaction on microporous biochar to construct mesopores, resulting in multi-level porous biochar rich in micropores and mesopores. S4 The obtained multi-level porous biochar rich in micropores and mesopores is ground and sifted by hydrocyclone sieving to obtain biochar powder with a particle size range of 20~300μm. S5 uses an impregnation method to load active metals onto biochar powder to obtain an unreduced biochar-based catalyst. S6 uses the non-condensable gas B obtained in step S2 to reduce the unreduced biochar-based catalyst to obtain the final biochar-based catalyst.

2. The method for preparing a biochar-based catalyst for deoxygenation and upgrading of bio-oil suspension bed according to claim 1, characterized in that, In step S1, the biomass is one of the following: fruit shells, wood, straw, industrial by-products, and agricultural livestock and poultry manure, or a combination of at least two of them.

3. The method for preparing a biochar-based catalyst for deoxygenation and upgrading of bio-oil suspension bed according to claim 1, characterized in that, In step S1, the rapid pyrolysis reaction conditions are: pyrolysis temperature of 400~700℃, heating rate of 1000~5000 K / s, and pyrolysis time of 1~30 s; the products obtained from the rapid pyrolysis reaction of biomass are cooled to obtain bio-oil, biochar, and non-condensable gas A.

4. The method for preparing a biochar-based catalyst for deoxygenation and upgrading of bio-oil suspension bed according to claim 1, characterized in that, In step S2, the conditions for the first stage of activation reaction are as follows: the activation temperature is 800~900℃, the activation atmosphere is non-condensable gas A, the heating rate is 3℃ / min~10℃ / min, and the activation time is 0.5~4 h.

5. The method for preparing a biochar-based catalyst for deoxygenation and upgrading of bio-oil suspension bed according to claim 1, characterized in that, In step S3, the conditions for the second stage activation reaction are: the activation temperature is 250~350℃, the activation atmosphere is air, and the activation time is 0.5~4 h; after the activation reaction, the microporous-mesoporous hierarchical biochar obtained is rich in micropores and has a micropore volume of 40~50% and a mesopore volume of 50~60%.

6. The method for preparing a biochar-based catalyst for deoxygenation and upgrading of bio-oil suspension bed according to claim 1, characterized in that, In step S4, the grinding particle size range of the multi-level porous biochar is 70~150μm during the grinding and cyclone screening.

7. The method for preparing a biochar-based catalyst for deoxygenation and upgrading of bio-oil suspension bed according to claim 1, characterized in that, In step S5, the active metal is at least two of Co, Ni, W, Mo, Cr, Fe, Nb, Zr, Ti, and Ce; the active metal is loaded onto the pore surface of the biochar powder carrier using an equal-volume impregnation method; the biochar powder is immersed in an active metal salt solution and ultrasonically dispersed for 0.5-2 h, followed by drying and calcination to obtain a biochar-based catalyst loaded with the active metal; the calcination process is as follows: the biochar powder loaded with the active metal is calcined at 300-550℃ for 1-4 h in an inert gas environment to obtain an unreduced biochar-based catalyst; the inert gas is one of nitrogen, argon, and helium.

8. The method for preparing a biochar-based catalyst for deoxygenation and upgrading of bio-oil suspension bed according to claim 1, characterized in that, In step S6, the non-condensable gas B obtained in step S2 is used as the reducing gas for the biochar-based catalyst. The unreduced biochar-based catalyst is reduced at 300~500℃ to obtain the final biochar-based catalyst. The reduction treatment time is 1~4 h. The mass fraction of active metal loaded on the biochar powder support is 2~20%.

9. The application of the biochar-based catalyst prepared by any one of claims 1 to 8 in the deoxygenation and upgrading of bio-oil.

10. The application according to claim 9, characterized in that, The biochar-based catalyst prepared by any one of the methods described in claims 1 to 7 is used in the deoxygenation and upgrading reaction of the bio-oil obtained in step S1.

11. The application according to claim 9, characterized in that, Using a suspended bed reactor at 300-350℃ and 10-15MPa, based on a biochar-based catalyst, bio-oil is subjected to hydrodeoxygenation and upgrading reaction to obtain the target product oil phase.

12. A device for preparing a biochar-based catalyst for deoxygenation and upgrading of bio-oil in a suspended bed, characterized in that, It includes a pyrolysis unit (1), a carbon activation unit (2), a grinding and cyclone screening unit (3), an active metal loading unit (4), and a catalyst reduction unit (5). The pyrolysis unit (1) is used to carry out pyrolysis reactions on biomass to obtain bio-oil, biochar and non-condensable gas A; The biochar activation unit (2) is used to activate biochar to obtain multi-level porous biochar rich in micropores and mesopores. The grinding and cyclone screening unit (3) grinds and cyclones the obtained multi-level porous biochar rich in micropores and mesopores to obtain biochar powder. The active metal loading unit (4) includes a metal impregnation subunit (41) and a calcination subunit (42); the metal impregnation subunit (41) is used to impregnate biochar powder in an active metal salt solution and load the active metal salt onto the biochar powder; and then calcination is carried out by the calcination subunit (42) to obtain an unreduced biochar-based catalyst. The catalyst reduction unit (5) is used to reduce the unreduced biochar-based catalyst to obtain the final biochar-based catalyst.

13. An integrated device, characterized in that, The apparatus includes the biochar-based catalyst preparation device as described in claim 12, and a slurry bed reactor (6); the slurry bed reactor (6) is used to perform a hydrodeoxygenation and upgrading reaction on bio-oil to obtain the target product oil phase.

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