Method for preparing broad-spectrum organic solvent soluble lignin
The catalyst prepared through catalytic reaction is used to improve the solubility of lignin, which solves the problems of poor lignin solubility and environmental pollution, and achieves efficient dissolution and wide application of lignin in a variety of organic solvents.
Patent Information
- Application Number
- CN202510483464.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-17
- Publication Date
- 2025-06-24
AI Technical Summary
In the prior art, lignin has poor solubility in conventional organic solvents, which limits its synthesis application in fine chemicals, polymer materials and other functional materials, and traditional acid-base extraction processes have a greater pollution to the environment.
Through the catalytic reaction process, catalysts with high catalytic activity are prepared, including Ni/TiO2, Co/TiO2, etc., which are used to mix with lignocellulose powder and water, react under optimized temperature, pressure and time conditions, and improve the compatibility of lignin in various organic solvent systems.
It has achieved efficient dissolution of lignin in broad-spectrum organic solvents, enhanced its application potential in the fields of fine chemicals and functional materials, and reduced environmental pollution.
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Abstract
Description
Technical Field
[0001] The present invention belongs to the technical field of lignin preparation, and particularly relates to a method for preparing a broad-spectrum organic solvent-soluble lignin. Background Art
[0002] Lignin is one of the most abundant renewable aromatic polymers on earth, accounting for about 15 - 30% of the content in lignocellulosic biomass. As the only naturally occurring polymer material rich in benzene ring skeletons, lignin has a complex molecular structure, which contains a large number of C - O and C - C bonds, making it an ideal precursor for the synthesis of aromatic chemicals. The efficient conversion of lignin can not only alleviate the increasingly severe shortage of petrochemical resources, but also effectively reduce the environmental pollution caused by the use of fossil fuels, while promoting the industrialization process of biomass-based sustainable chemicals. Therefore, how to efficiently and economically utilize lignin and achieve its upgrade transformation from low-value by-products to high-value chemicals has become one of the important research directions in the current biomass refining field.
[0003] At present, lignin is mainly produced in large quantities as a by-product of the paper and pulp industry and other biorefining processes. Statistical data shows that the global lignin production in 2024 was approximately 60 million tons, and it is expected to continue to grow at a compound annual growth rate of 4.9% from 2025 to 2030. As one of the major producers of the global paper and pulp industry, China also ranks among the top in lignin production. However, due to the highly heterogeneous molecular structure of lignin, its depolymerization and conversion are difficult, resulting in only about 2% of lignin being recycled globally at present, while the vast majority of lignin is still directly burned in a low-value manner for energy recovery. This traditional treatment method not only fails to fully explore the chemical potential of lignin, but also leads to resource waste and increased carbon dioxide emissions, which is not conducive to the realization of sustainable development goals.
[0004] Despite a large number of studies on the high-value utilization of lignin in recent years, commercial applications still face many technical bottlenecks. Among them, the poor solubility of lignin in conventional organic solvents is an important factor restricting its further development and utilization. Due to the complex structure of lignin, there are a large number of C - O bonds, C - C bonds and cross-linked structures in the molecule, making it show extremely low solubility and difficult to be directly used in the synthesis of fine chemicals, polymer materials and other functional materials. In addition, existing lignin dissolution strategies often involve harsh conditions (such as strong acid and strong base environments) or expensive ionic liquids, which limit their promotion in industrial applications. Therefore, developing an efficient, mild and economically feasible lignin dissolution method to improve its compatibility in organic solvent systems and expand its applications in the fields of functional materials and fine chemicals has become a key technical requirement for the high-value utilization of lignin. Summary of the Invention
[0005] The present invention provides a method for efficiently preparing a broad-spectrum organic solvent-soluble lignin, aiming to overcome the limitation of poor solubility in existing lignin preparation technologies and reduce the environmental pollution caused by traditional acid-base extraction processes. Through a catalytic reaction process, this method improves the compatibility of lignin in various organic solvent systems, thereby broadening its application potential in the fields of fine chemicals and functional materials. The lignin prepared below can be dissolved in most organic solvents, including various alcohol solvents, furan solvents, benzene solvents, etc., and the lignin can be miscible with alcohol solvents. The specific preparation steps are as follows:
[0006] (1) Feed the raw lignocellulosic biomass raw material into a pulverizer for mechanical pulverization to achieve a predetermined particle size distribution, so as to increase the specific surface area and improve the contact efficiency between the catalyst and the lignin component during the subsequent reaction process.
[0007] (2) Prepare the catalyst by the equal-volume impregnation method. The catalyst includes a carrier and an active component; the carrier is one of SiO2, Al2O3, CeO2, ZrO2, MgO, ZnO, TiO2, Fe2O3; the active component includes one or more of Co, Cu, Ni, Ag, Fe;
[0008] Further, the catalyst is Ni / TiO2, Co / TiO2, Ni / Al2O3, Fe / SiO2, Ag / ZnO, Cu / ZnO.
[0009] The specific preparation method of the catalyst is: dissolve the metal precursor in an appropriate amount of deionized water to prepare a solution with a certain concentration of the metal precursor. Subsequently, place the catalyst carrier in the solution to allow the solution to fully infiltrate the surface of the carrier, and carry out impregnation under suitable conditions. After static adsorption for a certain period of time, dry the obtained solid, and calcine it at high temperature and then reduce it to obtain a catalyst with high catalytic activity.
[0010] (3) Mix the lignocellulose powder, the catalyst and an appropriate amount of water in a set ratio, and place them in a closed reaction vessel. React under optimized temperature, pressure and time conditions. After the reaction, the lignin component will naturally float on the surface of the water solvent, thereby preparing a broad-spectrum organic solvent-soluble lignin.
[0011] Preferably, in step (1), the raw lignocellulosic biomass includes at least one of corn straw, soybean straw, rice straw, poplar wood and pine wood, and the particle size distribution of the lignocellulose powder is 50-100 mesh for the lignin powder.
[0012] Preferably, in step (2), the catalyst support is one of SiO2, Al2O3, CeO2, ZrO2, MgO, ZnO, TiO2, Fe2O3;
[0013] Preferably, in step (2), the metal precursor is a soluble metal salt, including one of Co(NO3)2, Cu(NO3)2, Ni(NO3)2, AgNO3, Fe(NO3)3.
[0014] Preferably, in step (2), the loading of the active component of the catalyst is 1-20 wt.%.
[0015] Preferably, in step (2), the calcination temperature is 200-500 °C and the time is 1-6 h.
[0016] Preferably, in step (2), the reduction is carried out in a hydrogen atmosphere, the reaction temperature is 200-500 °C, and the time is 1-6 h.
[0017] Preferably, in step (2), the impregnation time is 1-6 h.
[0018] Preferably, in step (3), the reaction temperature is 200-300 °C, the time is 1-3 h, and the hydrogen pressure is 1-5 MPa;
[0019] Preferably, in step (3), the mass ratio of the lignocellulose powder to the catalyst is 1:0.1-2 (such as 4:1.5);
[0020] Preferably, in step (3), the dosage ratio of the lignocellulose powder to water is 1 g:10-100 mL.
[0021] The beneficial effects of the present invention are as follows:
[0022] The present invention provides a method for efficiently preparing a broad-spectrum organic solvent-soluble lignin, aiming to overcome the limitation of poor solubility in the existing lignin preparation technology and reduce the environmental pollution caused by the traditional acid-base extraction process. Through the catalytic reaction process, this method improves the compatibility of lignin in various organic solvent systems, including various alcohol solvents, furan solvents, benzene solvents, etc., thereby broadening its application potential in the fields of fine chemicals and functional materials. The lignin prepared in the following examples was detected by the Klason method, and the purity of lignin was 99.9%. Detailed implementation manners
[0023] The following further illustrates the present invention through specific examples. The examples described in the present invention are only for the illustration of the present invention and do not limit the scope of the present invention.
[0024] Example 1
[0025] The lignocellulose powder and the catalyst are prepared according to the following method:
[0026] (1) Put pine wood into a crusher for mechanical crushing. After sieving, the particle size distribution of the lignocellulose powder is 90 - 100 mesh;
[0027] (2) Dissolve 0.1556 g of Ni(NO3)2 in 100 mL of deionized water to prepare a solution of the metal precursor. Subsequently, place 5 g of the TiO2 support in the solution to fully wet the surface of the support, and perform impregnation at room temperature. After 6 h of static adsorption, dry the obtained solid, and calcine it at 400 °C for 4 h. The calcined catalyst is reduced in an H2 atmosphere at a reduction temperature of 400 °C and a reduction time of 1 h to obtain a catalyst with a Ni metal loading of 1 wt.%;
[0028] The preparation method of the TiO2 support is as follows: At room temperature, add 12.5 mL of tetrabutyl titanate [Ti(OC4H9)4] and 1.5 mL of a 40 wt.% hydrofluoric acid solution to a 50 mL dry stainless steel autoclave lined with polytetrafluoroethylene and mix evenly. Subsequently, carry out a constant temperature reaction in a forced air drying oven at 180 °C for 24 hours. After naturally cooling to room temperature, collect the generated white powder, wash it repeatedly with ethanol and deionized water, dry it overnight in an oven at 80 °C, then place the sample in a muffle furnace, heat it to 400 °C at a heating rate of 2 °C / min, and hold it at 400 °C in dry air for 2 h.
[0029] Lignin preparation reaction
[0030] Weigh 4 g of the lignocellulose powder and 1.5 g of the catalyst obtained in steps (1) and (2), mix them with 50 mL of water, add them to a reaction kettle, fill it with 3 MPa of hydrogen, and react at 250 °C for 3 h. After the reaction is completed, filter, dry, and weigh and analyze that the mass of lignin is 0.6956 g. Calculated based on the lignin content in pine wood accounting for 20.1%, the yield is 86.5%.
[0031] Example 2
[0032] The lignocellulose powder and the catalyst are prepared according to the following method:
[0033] (1) Put soybean straw into a crusher for mechanical crushing. After sieving, the particle size distribution of the lignocellulose powder is 90 - 100 mesh;
[0034] (2) The same as Example 1.
[0035] Lignin preparation reaction
[0036] Weigh 4 g of the lignocellulose powder and 1.5 g of the catalyst obtained in steps (1) and (2), mix them with 50 mL of an aqueous solution, add the mixture into a reaction kettle, fill it with 3 MPa of hydrogen gas, and react at 250 °C for 3 h. After the reaction, weigh and analyze the mass of lignin, which is 0.1056 g. Calculated based on the lignin content in soybean straw accounting for 16.9%, the yield is 15.6%.
[0037] Example 3
[0038] Prepare the lignocellulose powder and the catalyst according to the following method:
[0039] (1) The same as in Example 1.
[0040] (2) Dissolve 0.1550 g of Co(NO3)2 in 100 mL of deionized water to prepare a solution of a certain concentration of the metal precursor. Subsequently, place 5 g of the TiO2 support in the solution to fully wet the surface of the support, and perform impregnation under suitable conditions. After standing and adsorbing for a certain period of time, dry the obtained solid and calcine it at 400 °C for 4 h. After calcination, reduce the catalyst in an H2 atmosphere at a reduction temperature of 400 °C for 1 h to obtain a catalyst with a Co metal loading of 1 wt.%.
[0041] The preparation method of the TiO2 support is the same as in Example 1.
[0042] Lignin preparation reaction
[0043] Weigh 4 g of the lignocellulose powder and 1.5 g of the catalyst obtained in steps (1) and (2), mix them with 50 mL of an aqueous solution, add the mixture into a reaction kettle, fill it with 3 MPa of hydrogen gas, and react at 250 °C for 3 h. After the reaction, filter, dry, weigh and analyze the mass of lignin, which is 0.4123 g. Calculated based on the lignin content in pine wood accounting for 20.1%, the yield is 51.3%.
[0044] Example 4
[0045] Prepare the lignocellulose powder and the catalyst according to the following method:
[0046] (1) The same as in Example 1;
[0047] (2) Dissolve 0.4668g Ni(NO3)2 in 100mL deionized water to prepare a solution of a certain concentration of metal precursor. Subsequently, place 5g Al2O3 carrier in the solution, allow the solution to fully infiltrate the carrier surface, and impregnate under appropriate conditions. After 6 hours of static adsorption, the obtained solid is dried and calcined at 400°C for 4 hours. The calcined catalyst is then reduced in a H2 atmosphere at a reduction temperature of 400°C for 1 hour to obtain a catalyst with a Ni metal loading of 3wt.%;
[0048] The Al2O3 carrier used is a commercial carrier from Aladdin Company, with a particle size of 10 nm, a purity of 99.9%, and a γ phase.
[0049] Lignin preparation reaction
[0050] The lignocellulose powder and catalyst obtained in steps (1) and (2) were weighed, 4 g of lignocellulose powder and 1.5 g of catalyst were mixed with 50 mL of aqueous solution and added to a reactor, filled with 3 MPa of hydrogen, and reacted at 250° C. for 3 h. After the reaction was completed, the mixture was filtered and dried, and the weight of lignin was weighed and analyzed to be 0.0017 g. Based on the lignin content of 20.1% in pine wood, the yield was 0.2%.
[0051] Example 5
[0052] Lignocellulose powder and catalyst were prepared as follows:
[0053] (1) Pine wood is put into a grinder for mechanical crushing, and after passing through a sieve, a lignocellulose powder with a particle size distribution of 50-60 mesh is obtained;
[0054] (2) Dissolve 0.4668g Ni(NO3)2 in 100mL deionized water to prepare a solution of a certain concentration of metal precursor. Subsequently, place 5g TiO2 carrier in the solution, allow the solution to fully infiltrate the carrier surface, and impregnate under appropriate conditions. After 6 hours of static adsorption, the obtained solid is dried and calcined at 400°C for 4 hours. The calcined catalyst is then reduced in a H2 atmosphere at a reduction temperature of 400°C for 1 hour to obtain a catalyst with a Ni metal loading of 3wt.%;
[0055] The preparation method of the TiO2 carrier is the same as that of Example 1
[0056] Lignin preparation reaction
[0057] The pretreated lignocellulose powder and catalyst obtained in steps (1) and (2) were weighed. 4 g of lignocellulose powder and 1.5 g of catalyst were taken, mixed with 50 mL of aqueous solution, and then added into a reaction kettle. 3 MPa of hydrogen was filled, and the reaction was carried out at 250 °C for 3 h. After the reaction ended, the lignin mass was weighed and analyzed to be 0.5231 g. Calculated based on the lignin content in pine wood accounting for 20.1%, the yield was 65.1%.
[0058] Example 6
[0059] The lignocellulose powder and catalyst were prepared according to the following method:
[0060] (1) The same as Example 1;
[0061] (2) 1.5560 g of Ni(NO3)2 was dissolved in 100 mL of deionized water to prepare a solution of a certain concentration of metal precursor. Subsequently, 5 g of TiO2 support was placed in the solution to fully wet the surface of the support, and impregnation was carried out under suitable conditions. After 6 h of static adsorption, the obtained solid was dried and calcined at 400 °C for 4 h. After calcination, the catalyst was then reduced in an H2 atmosphere at a reduction temperature of 400 °C and a reduction time of 1 h to obtain a catalyst with a Ni metal loading of 10 wt.%.
[0062] The preparation method of the TiO2 support was the same as that in Example 1.
[0063] Lignin preparation reaction
[0064] The lignocellulose powder and catalyst obtained in steps (1) and (2) were weighed. 4 g of lignocellulose powder and 1.5 g of catalyst were taken, mixed with 50 mL of aqueous solution, and then added into a reaction kettle. 3 MPa of hydrogen was filled, and the reaction was carried out at 250 °C for 3 h. After the reaction ended, filtration, drying were carried out, and the lignin mass was weighed and analyzed to be 0.4962 g. Calculated based on the lignin content in pine wood accounting for 20.1%, the yield was 61.7%.
[0065] Example 7
[0066] The lignocellulose powder and catalyst were prepared according to the following method:
[0067] (1) Pine wood was put into a crusher for mechanical crushing, and after sieving, the particle size distribution of the lignocellulose powder was 90 - 100 mesh;
[0068] (2) Dissolve 1.5560 g of Ni(NO3)2 in 100 mL of deionized water to prepare a solution of a metal precursor with a certain concentration. Subsequently, place 5 g of the TiO2 support in the solution to allow the solution to fully wet the surface of the support, and carry out impregnation under appropriate conditions. After 6 h of static adsorption, dry the obtained solid, calcine it at 400 °C for 4 h, and then carry out reduction under a H2 atmosphere. The reduction temperature is 500 °C and the reduction time is 1 h to obtain a catalyst with a Ni metal loading of 10 wt.%.
[0069] The preparation method of the TiO2 support is the same as that in Example 1.
[0070] Lignin preparation reaction
[0071] Weigh 4 g of the lignocellulose powder and 1.5 g of the catalyst obtained in steps (1) and (2), mix them with 50 mL of an aqueous solution, add them to a reaction kettle, fill it with 3 MPa of hydrogen, and react at 250 °C for 3 h. After the reaction is completed, filter, dry, and weigh and analyze that the mass of lignin is 0.5927 g. Calculated based on the lignin content in pine wood accounting for 20.1%, the yield is 73.7%.
[0072] Example 8
[0073] Prepare the lignocellulose powder and the catalyst according to the following method:
[0074] (1) Put pine wood into a crusher for mechanical crushing. After sieving, the particle size distribution of the lignocellulose powder is 90 - 100 mesh;
[0075] (2) Dissolve 0.1556 g of Ni(NO3)2 in 100 mL of deionized water to prepare a solution of a metal precursor with a certain concentration. Subsequently, place 5 g of the TiO2 support in the solution to allow the solution to fully wet the surface of the support, and carry out impregnation under appropriate conditions. After 6 h of static adsorption, dry the obtained solid, calcine it at 400 °C for 4 h, and then carry out reduction under a H2 atmosphere. The reduction temperature is 400 °C and the reduction time is 1 h to obtain a catalyst with a Ni metal loading of 1 wt.%.
[0076] The preparation method of the TiO2 support is the same as that in Example 1.
[0077] Lignin preparation reaction
[0078] The lignocellulose powder and catalyst obtained in steps (1) and (2) were weighed, 4 g of lignocellulose powder and 1.5 g of catalyst were mixed with 50 mL of water and added to a reactor, filled with 3 MPa of hydrogen, and reacted at 300° C. for 3 h. After the reaction was completed, the mixture was filtered and dried, and the weight of lignin was weighed and analyzed to be 0.5120 g. Based on the lignin content of 20.1% in pine wood, the yield was 63.7%.
[0079] Example 9
[0080] Lignocellulose powder and catalyst were prepared as follows:
[0081] (1) Same as Example 1;
[0082] (2) Dissolve 4.3309g Fe(NO3)2 in 100mL deionized water to prepare a solution of a certain concentration of metal precursor. Subsequently, place 5g SiO2 carrier in the solution, allow the solution to fully infiltrate the carrier surface, and impregnate under appropriate conditions. After 6h of static adsorption, the obtained solid is dried and calcined at 400°C for 4h. The calcined catalyst is then reduced in a H2 atmosphere at a reduction temperature of 200°C and a reduction time of 6h to obtain a catalyst with an Fe metal loading of 20wt.%;
[0083] The SiO2 carrier used is a commercial carrier from Aladdin, which is hydrophilic and has a specific surface area of 200 m 2 / g.
[0084] Lignin preparation reaction
[0085] The lignocellulose powder and catalyst obtained in steps (1) and (2) were weighed, 4 g of lignocellulose powder and 1.5 g of catalyst were mixed with 50 mL of water and added to a reactor, filled with 3 MPa of hydrogen, and reacted at 300° C. for 3 h. After the reaction was completed, the mixture was filtered and dried, and the weight of lignin was weighed and analyzed to be 0.0820 g. Based on the lignin content of pine wood accounting for 20.1%, the yield was 10.2%.
[0086] Example 10
[0087] Lignocellulose powder and catalyst were prepared as follows:
[0088] (1) Same as Example 1;
[0089] (2) Dissolve 0.3937 g of AgNO₃ in 100 mL of deionized water to prepare a solution of a metal precursor with a certain concentration. Subsequently, place 5 g of the ZnO support in the solution to fully wet the surface of the support, and carry out impregnation under appropriate conditions. After 6 h of static adsorption, the obtained solid is dried and calcined at 400 °C for 4 h. After that, the calcined catalyst is reduced under a H₂ atmosphere at a reduction temperature of 300 °C and a reduction time of 4 h to obtain a catalyst with an Ag metal loading of 5 wt.%.
[0090] The ZnO support used is a commercial support from Aladdin, with a purity > 99.99%.
[0091] Lignin preparation reaction
[0092] Weigh 4 g of the lignocellulose powder and 1.5 g of the catalyst obtained in steps (1) and (2), mix them with 50 mL of water, add them to the autoclave, fill it with 3 MPa of hydrogen, and react at 300 °C for 3 h. After the reaction, filter, dry, and weigh. The mass of lignin is 0.0426 g. Calculated based on the lignin content in pine wood accounting for 20.1%, the yield is 5.3%.
[0093] Example 11
[0094] Prepare the lignocellulose powder and the catalyst according to the following method:
[0095] (1) The same as Example 1;
[0096] (2) Dissolve 2.2136 g of Cu(NO₃)₂ in 100 mL of deionized water to prepare a solution of a metal precursor with a certain concentration. Subsequently, place 5 g of the CeO₂ support in the solution to fully wet the surface of the support, and carry out impregnation under appropriate conditions. After 6 h of static adsorption, the obtained solid is dried and calcined at 400 °C for 4 h. After that, the calcined catalyst is reduced under a H₂ atmosphere at a reduction temperature of 300 °C and a reduction time of 4 h to obtain a catalyst with a Cu metal loading of 15 wt.%.
[0097] The CeO₂ support used is a commercial support from Aladdin, with a particle size of 20 - 50 nm and a purity > 99.5%.
[0098] Lignin preparation reaction
[0099] Weigh the lignocellulose powder and catalyst obtained in steps (1) and (2). Weigh 4 g of lignocellulose powder and 1.5 g of catalyst, mix them with 50 mL of water, then add them into a reaction kettle, fill it with 3 MPa of hydrogen, and react at 300 °C for 3 h. After the reaction is completed, filter, dry, and weigh and analyze. The mass of lignin is 0.2396 g. Calculated based on the lignin content in pine wood accounting for 20.1%, the yield is 29.8%.
[0100] Table 1
[0101]
[0102]
[0103] Effect Example
[0104] Dissolve the lignin prepared in the above-mentioned example in different solvents and test its solubility. The test results are shown in Table 2 below. The lignin obtained by the process of the present invention has broad-spectrum solubility in organic solvents.
[0105] Table 2
[0106] Solvent Whether it dissolves Methanol Yes Ethanol Yes Isopropanol Yes n-Butanol Yes Ethylene glycol Yes Toluene Yes Xylene Yes Furan Yes Tetrahydrofuran Yes Acetone Yes Ethyl acetate Yes
[0107] It should be noted that the above is the preferred embodiment of the present invention. It should be pointed out that for those skilled in the art, without departing from the method of the present invention, several improvements and supplements can be made, and these improvements and supplements should also be regarded as the protection scope of the present invention.
Claims
1. A method for preparing broad-spectrum organic solvent-soluble lignin, characterized in that: The steps include: The lignocellulose powder, catalyst and water are placed in a closed reaction vessel for reaction; after the reaction is completed, the lignin floats on the surface to obtain a broad-spectrum organic solvent-soluble lignin.
2. The method for preparing the broad-spectrum organic solvent-soluble lignin according to claim 1, characterized in that: The source of the lignocellulose powder includes at least one of corn straw, soybean straw, rice straw, poplar and pine.
3. The method for preparing the broad-spectrum organic solvent-soluble lignin according to claim 1, characterized in that: The particle size distribution of the lignin powder is 50-100 meshes.
4. The method for preparing the broad-spectrum organic solvent-soluble lignin according to claim 1, characterized in that: The catalyst comprises a carrier and an active component; The carrier is one of SiO2, Al2O3, CeO2, ZrO2, MgO, ZnO, TiO2, and Fe2O3; The active components include one or more of Co, Cu, Ni, Ag, and Fe; The loading amount of the active component in the catalyst is 1-20 wt.%.
5. The method for preparing broad-spectrum organic solvent-soluble lignin according to claim 4, characterized in that: The catalyst is prepared by an equal volume impregnation method, and the specific steps are as follows: placing the catalyst carrier in a solution of a metal precursor, impregnating, drying, and calcining under high temperature conditions before reduction.
6. The method for preparing broad-spectrum organic solvent-soluble lignin according to claim 5, characterized in that: The metal precursor is a soluble metal salt, including Co(NO3)2, Cu(NO3)2, Ni(NO3)2, AgNO3, and Fe(NO3)3.
7. The method for preparing broad-spectrum organic solvent-soluble lignin according to claim 5, characterized in that: The impregnation time is 1-6 h; the calcination time is 1-6 h, and the temperature is 200-500 ° C; the reduction is carried out in a hydrogen atmosphere, at a temperature of 200-500 ° C, and for 1-6 h.
8. The method for preparing broad-spectrum organic solvent-soluble lignin according to claim 1, characterized in that: The reaction temperature is 200-300°C, the reaction time is 1-3 h, and the hydrogen pressure is 1-5 MPa.
9. The method for preparing broad-spectrum organic solvent-soluble lignin according to claim 1, characterized in that: The mass ratio of the wood cellulose powder to the catalyst is 1:0.1-2.