Preparation method of composite material for removing acid hydrolysis and fermentation inhibitors of agriculture and forestry fibers

Abstract

The invention discloses a preparation method of a composite material for removing acid hydrolysis and fermentation inhibitors of agriculture and forestry fibers, and belongs to the technical field of development and utilization of waste biomass resources. The method comprises the following steps: firstly, preparing phosphoric acid mixed slurry containing the bamboo-source residues from the crushed and screened bamboo-source residues and a phosphoric acid solution; adding calcium oxide or calcium hydroxide, mixing and homogenizing to obtain mixed slurry containing bamboo source residues and basic calcium phosphate, and drying the mixed slurry into powder; placing the powder in a quartz tube for activating treatment to obtain a bamboo source carbon-based material; and dipping in a reducing agent solution, and drying to obtain the composite material for removing the acid hydrolysis fermentation inhibitor of the agriculture and forestry fibers. The composite material prepared by the invention has an integrated synergistic effect of adsorption, neutralization, reduction and the like, and has a function of removing fermentation inhibitors under various types of acidic conditions; and the element distribution uniformity is good, the water dispersibility is good, the normal-temperature storage stability is good, and the composite material can be added into a fluid and a semi-fluid and has a good application prospect.

Description

Technical Field

[0001] The invention belongs to the technical field of development and utilization of waste biomass resources, and specifically relates to a method for preparing a composite material for removing inhibitors of acid hydrolysis and fermentation of agricultural and forestry fibers. Background Art

[0002] At present, the amount of forest biomass resources in my country is about 350 million tons, and the comprehensive utilization rate of forest biomass is about 60%. The amount of agricultural straw resources in my country is about 1 billion tons per year, and the comprehensive utilization rate is nearly 90%. However, the technology of agricultural and forestry food and feed utilization has developed slowly, with high costs, poor stability, and generally small industrial scale. The high-value food and feed utilization technology of agricultural and forestry lignin resources needs to be upgraded urgently. Agricultural and forestry lignin is mainly composed of cellulose, hemicellulose and lignin. Among them, hemicellulose can be degraded into small molecular sugars and oligosaccharides after acid hydrolysis, and cellulose can be hydrolyzed into glucose by cellulase, and then can be converted by microorganisms to prepare single-cell protein and amino acids for feed; the unhydrolyzed cellulose component can be further fermented to prepare fiber compound feed with intestinal prebiotic function. It is estimated that by 2035, my country's energy feed gap will exceed 88 million tons, and the protein feed gap will exceed 124 million tons. It is urgent to develop high-value new resource feed technology and innovative wood fiber biorefining technology. The development of agricultural and forestry biomass fermentation feed is of great strategic significance to ensuring my country's food security and improving the effective utilization of agricultural and forestry residue resources.

[0003] Agricultural and forestry fiber biorefining technology usually includes the following parts: saccharification pretreatment, removal of fermentation inhibitors, biological fermentation, separation and purification, etc. No matter what pretreatment and hydrolysis method is used, it is difficult to completely avoid the production of inhibitory compounds. Considering cost and efficiency, saccharification pretreatment is currently mainly based on sulfuric acid method in China. However, sulfuric acid saccharification treatment is prone to produce harmful components such as aldehyde acid and phenols to microorganisms, so it is necessary to remove fermentation inhibitors. The removal of fermentation inhibitors mainly includes biological removal, water washing removal, alkalinization treatment, adsorption filtration, etc., and water washing method is mainly used in industry. The above fermentation inhibitor removal technology has the disadvantages of cumbersome operation, high energy consumption, low efficiency, and high fermentation substrate loss rate. Bamboo resources are a renewable biomass with fast growth, high yield, and wide planting. my country has the most abundant bamboo resources. my country's bamboo products industry is developing rapidly, and the output of bamboo processing waste is huge. Bamboo processing waste is used as raw material. Bamboo-derived biomass charcoal and its composite adsorption materials prepared by chemical activation often have the advantages of low cost and good performance. Biochar can effectively remove harmful substances in feed, such as adsorbing mycotoxins and toxic phenolic acids, decolorizing and deodorizing, etc.; however, biochar has limited adsorption performance for polar compounds, and the adsorption efficiency in complex media systems may fluctuate greatly, which restricts its application scenarios and efficiency. Basic calcium phosphate can be generated by the reaction of phosphoric acid and excess calcium oxide or calcium hydroxide. It can be regarded as a mixture of calcium phosphate and calcium hydroxide, and has good biocompatibility and sustained release. It can slowly neutralize the acidic components in the medium. Basic calcium phosphate is very easy to precipitate, so its dispersibility is poor, which affects the removal efficiency of acidic components in the medium. Adding a reducing agent can effectively resist free radicals in acid hydrolyzates and microbial inhibitors such as aldehyde compounds, but the reducing agent is easily oxidized and often has poor stability, and cannot play a sustained removal role.

[0004] In order to solve the above problems, the present invention uses bamboo residues as raw materials, basic calcium phosphate and a reducing agent as activators, and utilizes high-temperature activation, multi-stage homogenization combined with impregnation compounding preparation technology to develop a bamboo-derived carbon-based composite material preparation method that can be widely used in the removal of wood fiber acid hydrolysis and fermentation inhibitors. It is beneficial to achieve integrated removal of fermentation inhibitors, effectively improve the fermentation conversion efficiency after fiber saccharification, and then increase the microbial conversion yield, thereby realizing the high-value and efficient feed utilization of agricultural and forestry wood fibers, and forming a new quality productivity technology reserve of "fiber sugar instead of grain" to ensure national food security. Summary of the invention

[0005] The technical problem solved by the present invention is to provide a method for preparing a composite material for removing inhibitors of acid hydrolysis and fermentation of agricultural and forestry fibers; another technical problem to be solved by the present invention is to provide a use of a composite material for removing inhibitors of acid hydrolysis and fermentation of agricultural and forestry fibers.

[0006] In order to solve the above technical problems, the technical solution adopted by the present invention is as follows:

[0007] A method for preparing a composite material for removing inhibitors of acid hydrolysis and fermentation of agricultural and forestry fibers comprises the following steps:

[0008] (1) preparing a phosphoric acid mixed slurry containing bamboo residues from the crushed and sieved bamboo residues and a phosphoric acid solution; then adding calcium oxide or calcium hydroxide, fully mixing and reacting and homogenizing to obtain a mixed slurry containing bamboo residues and basic calcium phosphate, and then drying the mixed slurry into powder;

[0009] (2) placing the powder of step (1) in a quartz tube for activation treatment to obtain a dark brown powder, which is a bamboo-derived carbon-based material containing basic calcium phosphate;

[0010] (3) The bamboo-derived carbon-based material containing basic calcium phosphate in step (2) is immersed in a reducing agent solution and dried, and the resulting brown powder is a composite material that can be used to remove inhibitors of acid hydrolysis and fermentation of agricultural and forestry fibers.

[0011] In the step (1), the mass ratio of the bamboo residue to the phosphoric acid solution is 1:0.1-0.3; and the bamboo residue is soaked in the phosphoric acid solution for 2-12 hours.

[0012] The bamboo residues in step (1) include bamboo processing residues and bamboo shoot shells; the particle size after crushing and screening is 0.02-2 nm; the solid content of the prepared phosphoric acid mixed slurry containing bamboo residues is 12%-22%; the pH of the phosphoric acid mixed slurry containing bamboo residues is 1.5-3.5.

[0013] The mass ratio of the phosphoric acid mixed slurry containing bamboo residues to calcium oxide or calcium hydroxide in step (1) is 1:0.1-0.5; the stirring temperature of the mixed slurry and calcium oxide is 60-100° C.; and the stirring time is 2-6 hours.

[0014] The solid content of the mixed slurry containing bamboo residues and basic calcium phosphate prepared in the step (1) is 13% to 25%; the pH of the mixed slurry containing bamboo residues and basic calcium phosphate is 7.5 to 10.5; the rotation speed of the high-speed shearing treatment is 5000 to 20000 rpm; the shearing time is 5 to 30 minutes; the pressure of the high-pressure homogenization treatment is 15000 to 25000 PSI; and the homogenization treatment time is 2 to 15 minutes.

[0015] The activation treatment conditions in step (2) are to increase the temperature to 340-420° C. at a heating rate of 5-15° C. / min and keep the temperature for 1-6 hours.

[0016] In the step (3), the mass ratio of the bamboo-derived carbon-based material containing basic calcium phosphate to the reducing agent solvent is 1:0.05-0.15; the type of the reducing agent is sodium sulfite or ammonium sulfite; and the mass fraction of the reducing agent solution is 1%-5%.

[0017] The composite material prepared by the method is used for removing inhibitors of acid hydrolysis and fermentation of agricultural and forestry fibers.

[0018] The composite material for removing inhibitors of acid hydrolysis and fermentation of agricultural and forestry fibers is used in removing inhibitors of acid hydrolysis and fermentation of agricultural and forestry fibers.

[0019] The fiber acid includes inorganic acid, organic acid or mixed acid hydrolyzate.

[0020] Compared with the prior art, the present invention has the following advantages:

[0021] (1) The present invention utilizes bamboo waste biomass resources, which are abundant and inexpensive, as raw materials, has a simple and easy production process, and is conducive to the high-value utilization of waste biomass resources.

[0022] (2) The preparation method of the present invention is simple, environmentally friendly, and has good process stability. The bamboo residue is further processed, and the amount of basic calcium phosphate generated by the reaction of phosphoric acid and calcium oxide or calcium hydroxide is controlled, and the ratio of the basic calcium phosphate to the mixed slurry containing the bamboo residue and basic calcium phosphate is adjusted, and the content of the reducing agent is adjusted by an impregnation method to achieve optimal compounding; the biomass carbon material has a high specific surface area and porosity, and has good uniform loading performance for basic calcium phosphate and the reducing agent. The prepared composite material has integrated synergistic effects such as adsorption, neutralization, and reduction, and has the effect of removing fermentation inhibitors under various types of acidic conditions; the composite material has good uniformity of element distribution, good water dispersibility, good storage stability at room temperature, can be added to fluids and semi-fluids, and has a wide range of applications.

[0023] (3) The main raw materials used in the present invention meet the requirements of food and feed additive raw materials. The prepared composite material has rich phosphorus and calcium content and also has the functions of phosphorus and calcium nutritional supplementation. It can be applied to the fields of food and feed industry. The present invention also has good application prospects in the fields of waste biomass resource development and utilization, biorefining, fermentation industry, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a scanning electron microscope image of the composite material for removing inhibitors of acid hydrolysis and fermentation of agricultural and forestry fibers prepared in Example 1 of the present invention;

[0025] Figure 2 This is a surface element distribution diagram of the composite material for removing inhibitors of acid hydrolysis and fermentation of agricultural and forestry fibers prepared in Example 1 of the present invention;

[0026] Figure 3 This is an energy spectrum element analysis diagram of the composite material for removing inhibitors of acid hydrolysis and fermentation of agricultural and forestry fibers prepared in Example 1 of the present invention. DETAILED DESCRIPTION

[0027] The present invention is further illustrated below in conjunction with specific examples. The examples are implemented based on the technical solutions of the present invention. It should be understood that these examples are only used to illustrate the present invention and are not used to limit the scope of the present invention.

[0028] Example 1

[0029] (1) 10 g of bamboo powder with a particle size of 0.05 to 1 nm after crushing and screening was slowly added to 100 mL of 3% phosphoric acid solution, and the mixture was fully stirred and soaked for 6 hours to obtain a phosphoric acid mixed slurry containing bamboo residues with a pH of about 2 and a solid content of about 12%; then 4 g of calcium hydroxide was added to the phosphoric acid mixed slurry containing bamboo residues, stirred at 90° C. for 4 hours, and then subjected to high-speed shear treatment at a shear speed of 15000 rpm for 10 minutes, and then subjected to high-pressure homogenization treatment at a pressure of 20000 PSI for 10 minutes to obtain a mixed slurry containing bamboo residues and basic calcium phosphate with a solid content of about 15%, and the mixed slurry was further dried into a powder of about 17 g;

[0030] (2) placing 17 g of the obtained powder in a quartz tube, heating the temperature to 380° C. at a heating rate of 5° C. / min for activation treatment for 3 h, and obtaining about 9.5 g of dark brown powder, which is a bamboo-derived carbon-based material containing basic calcium phosphate;

[0031] (3) The obtained 9.5 g of bamboo-derived carbon-based material containing basic calcium phosphate was placed in 50 mL of 2.5% sodium sulfite solution and fully immersed, and then vacuum dried at 50°C to constant weight. The obtained brown powder of about 10.7 g was a composite material that can be used to remove inhibitors of acid hydrolysis and fermentation of agricultural and forestry fibers.

[0032] Example 2

[0033] (1) 50 g of bamboo shoot shell powder with a particle size of 0.1 to 2 mm after crushing and screening is slowly added to 300 mL of 5% phosphoric acid solution, and the mixture is fully stirred and soaked for 12 hours to obtain a phosphoric acid mixed slurry containing bamboo residues with a pH value of about 1.5 and a solid content of about 19%; then 30 g of calcium oxide is added to the phosphoric acid mixed slurry containing bamboo residues, stirred at 100° C. for 6 hours, and then subjected to high-speed shear treatment at a shear speed of 20,000 rpm for 30 minutes, and then subjected to high-pressure homogenization treatment at a pressure of 25,000 PSI for 15 minutes to obtain a mixed slurry containing bamboo residues and basic calcium phosphate with a solid content of about 25%, and the mixed slurry is further dried into a powder of about 95 g;

[0034] (2) placing 95 g of the obtained powder in a quartz tube, heating the temperature to 420° C. at a heating rate of 15° C. / min for activation treatment for 6 h, and obtaining about 55 g of dark brown powder, which is a bamboo-derived carbon-based material containing basic calcium phosphate;

[0035] (3) The obtained 55 g bamboo-derived carbon-based material containing basic calcium phosphate was fully immersed in 165 mL of 5% potassium sulfite solution, and vacuum dried at 60°C to constant weight. The obtained brown powder of about 63.2 g was a composite material that can be used to remove inhibitors of acid hydrolysis and fermentation of agricultural and forestry fibers.

[0036] Example 3

[0037] (1) 5 g of bamboo powder with a particle size of 0.02 to 0.2 mm after crushing and screening was slowly added to 20 mL of 2.5% phosphoric acid solution, and the mixture was fully stirred and soaked for 2 hours to obtain a phosphoric acid mixed slurry containing bamboo residues with a pH value of about 3 and a solid content of about 22%; then 0.5 g of calcium hydroxide was added to the phosphoric acid mixed slurry containing bamboo residues, stirred at 60° C. for 2 hours, and then subjected to high-speed shear treatment at a shear speed of 5000 rpm for 5 minutes, and then subjected to high-pressure homogenization treatment at a pressure of 15000 PSI for 2 minutes to obtain a mixed slurry containing bamboo residues and basic calcium phosphate with a solid content of about 24%, and the mixed slurry was further dried into a powder of about 6 g;

[0038] (2) placing 6 g of the obtained powder in a quartz tube, heating the temperature to 340° C. at a heating rate of 5° C. / min for activation treatment for 1 h, and obtaining about 2 g of dark brown powder, which is the bamboo-derived carbon-based material containing basic calcium phosphate;

[0039] (3) The obtained 2 g of bamboo-derived carbon-based material containing basic calcium phosphate was fully immersed in 10 mL of 1.1% ammonium sulfite solution, and vacuum dried at 40°C to constant weight. The obtained brown powder of about 2.1 g was a composite material that can be used to remove inhibitors of acid hydrolysis and fermentation of agricultural and forestry fibers.

[0040] Example 4

[0041] (1) 1 kg of crushed and sieved bamboo shoot shell powder with a particle size of 0.05 to 2 mm is slowly added to 5 L of 5% phosphoric acid solution, and the mixture is fully stirred and soaked for 8 hours to obtain a phosphoric acid mixed slurry containing bamboo residues with a pH value of about 2 and a solid content of about 21%; then 250 g of calcium oxide is added to the phosphoric acid mixed slurry containing bamboo residues, stirred at 80° C. for 4 hours, and then subjected to high-speed shear treatment at a shear speed of 15,000 rpm for 10 minutes, and then subjected to high-pressure homogenization treatment at a pressure of 20,000 PSI for 15 minutes to obtain a mixed slurry containing bamboo residues and basic calcium phosphate with a solid content of about 24%, and the mixed slurry is further dried into powder, about 1.5 kg;

[0042] (2) placing the obtained 1.5 kg powder in multiple quartz tubes respectively, heating to 400 °C at a heating rate of 10 °C / min for activation treatment for 5 h, and obtaining about 0.7 kg dark brown powder, which is the bamboo-derived carbon-based material containing basic calcium phosphate;

[0043] (3) The obtained 0.7 kg bamboo-derived carbon-based material containing basic calcium phosphate was placed in 3.5 L of 2% sodium sulfite solution and fully immersed, and then vacuum dried at 45°C to constant weight. The obtained brown powder of about 0.77 kg was a composite material that can be used to remove inhibitors of acid hydrolysis and fermentation of agricultural and forestry fibers.

[0044] Example 5

[0045] (1) 200 g of bamboo powder with a particle size of 0.02 to 1 mm after crushing and screening was slowly added to 1.6 L of 1% phosphoric acid solution, and the mixture was fully stirred and soaked for 8 hours to obtain a phosphoric acid mixed pulp containing bamboo residues with a pH value of about 3.5 and a solid content of about 12%; then 20 g of calcium hydroxide was added to the phosphoric acid mixed pulp containing bamboo residues, stirred at 70° C. for 3 hours, and then subjected to high-speed shear treatment at a shear speed of 10,000 rpm for 15 minutes, and then subjected to high-pressure homogenization treatment at a pressure of 25,000 PSI for 10 minutes to obtain a mixed pulp containing bamboo residues and basic calcium phosphate with a solid content of about 13%, and the mixed pulp was further dried into a powder of about 236 g;

[0046] (2) placing the obtained 236 g powder in a quartz tube, heating it to 360° C. at a heating rate of 10° C. / min for activation treatment for 4 h, and obtaining about 76 g of dark brown powder, which is a bamboo-derived carbon-based material containing basic calcium phosphate;

[0047] (3) The obtained 76 g of bamboo-derived carbon-based material containing basic calcium phosphate was fully immersed in 250 mL of 3% potassium sulfite solution, and vacuum dried at 55°C to constant weight. The obtained brown powder of about 83 g was a composite material that can be used to remove inhibitors of acid hydrolysis and fermentation of agricultural and forestry fibers.

[0048] Example 6

[0049] The composite materials for removing inhibitors of acid hydrolysis and fermentation of agricultural and forestry fibers obtained in the above Examples 1-5 were analyzed for particle size distribution (including average particle size and particle size distribution coefficient, tested by laser particle size analyzer) and the results are shown in Table 1.

[0050] Table 1 Comparison of particle size distribution of composite materials obtained in Examples 1-5 in water

[0051] index Example 1 Example 2 Example 3 Example 4 Example 5 Particle size distribution (μm) 0.2-12.2 0.1-12.1 0.2-16.4 0.2-12.3 0.1-12.9 Average particle size (μm) 6.2 6.1 8.3 6.2 6.5 Particle size distribution coefficient 0.297 0.304 0.413 0.322 0.350

[0052] Examples 1-5 specifically show that they have good dispersibility in water, with a particle size distribution range of 0.1 to 18.5 μm and a distribution coefficient range of 0.296 to 0.413. From the particle size distribution test results of the data in Table 1, the average particle size is in the order of Example 2≈1≈4>5>3 from small to large, and the distribution coefficient is in the order of Example 1≈2>4>5>3 from small to large, which means that Examples 1 and 2 have better dispersibility in water than other Examples.

[0053] Examples 1-5 also show that they have good storage stability at room temperature, and there is no color change, no agglomeration, and no deterioration within six months of natural sealing at room temperature; among which Example 1 is Figure 1 and Figure 3 Scanning electron microscopy and energy spectrum analysis showed that basic calcium phosphate and reducing agent were mainly loaded on the bamboo-derived carbon-based materials in the form of attachment or embedding, and the element distribution was well uniform.

[0054] Example 7

[0055] The composite material for removing fermentation inhibitors in acid hydrolysis of agricultural and forestry fibers obtained in the above-mentioned Examples 1-5 is applied to the removal of fermentation inhibitors in the acid hydrolyzate of agricultural and forestry residues, including using a colorimetric method to determine the fermentation inhibitor content in the hydrolyzate, including the content of Maillard reaction products and phenolic compounds. The absorbance value (OD 420 ) is used to evaluate the content of Maillard reaction products, and the absorbance value (OD 420 ) was positively correlated with the content of Maillard reaction products; the absorbance value (OD 280 ) was used to evaluate the content of phenolic compounds, and the absorbance value (OD 280 ) and the content of phenolic compounds are positively correlated; the absorbance values ​​(after appropriate dilution) of the hydrolyzate without the composite materials obtained in Examples 1-5 (hereinafter referred to as: no-addition control) and the composite materials obtained in Examples 1-5 applied to different agricultural and forestry fiber hydrolyzates are measured and are shown in Tables 2-5 below.

[0056] Table 2 Comparison of absorbance values ​​of fermentation inhibitors in the composite materials obtained in Examples 1-5 applied to corn straw sulfuric acid hydrolyzate (0.6% sulfuric acid, hydrolyzed at 120°C for 1h, solid content 5%)

[0057]

[0058] Table 3 Comparison of absorbance values ​​of fermentation inhibitors in bamboo shoot shell sulfuric acid hydrolyzate (0.75% sulfuric acid, 110°C, hydrolyzed for 2h, solid content 6.5%) of the composite materials obtained in Examples 1-5

[0059]

[0060] Table 4 Comparison of absorbance values ​​of fermentation inhibitors in the composite materials obtained in Examples 1-5 applied to sulfuric acid hydrolyzate of Caragana korshinskii (0.5% sulfuric acid hydrolyzed at 130°C for 0.8h, solid content 4%)

[0061]

[0062]

[0063] Table 5 Comparison of absorbance values ​​of fermentation inhibitors in the composite materials obtained in Examples 1-5 applied to poplar wood sulfuric acid hydrolyzate (0.3% sulfuric acid, hydrolyzed at 105°C for 3h, solid content 2.5%)

[0064]

[0065] Examples 1-5 specifically show that they have a good removal effect on fermentation inhibitors in the hydrolyzate, including Maillard reaction products and phenolic compounds. The absorbance values ​​(OD 420 ) and absorbance value (OD 280 ) test results, the order of values ​​from small to large is Example 2≈1>4>5>3, which means that Examples 1 and 2 have better removal effects on fermentation inhibitors including Maillard reaction products and phenolic compounds in the hydrolyzate than other examples.

[0066] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for preparing a composite material for removing inhibitors of acid hydrolysis and fermentation of agricultural and forestry fibers, characterized in that: The following steps are involved: (1) preparing a phosphoric acid mixed slurry containing bamboo residues from the crushed and sieved bamboo residues and a phosphoric acid solution; then adding calcium oxide or calcium hydroxide, fully mixing and reacting and homogenizing to obtain a mixed slurry containing bamboo residues and basic calcium phosphate, and then drying the mixed slurry into powder; (2) placing the powder of step (1) in a quartz tube for activation treatment to obtain a dark brown powder, which is a bamboo-derived carbon-based material containing basic calcium phosphate; (3) The bamboo-derived carbon-based material containing basic calcium phosphate in step (2) is immersed in a reducing agent solution and dried, and the resulting brown powder is a composite material that can be used to remove inhibitors of acid hydrolysis and fermentation of agricultural and forestry fibers.

2. The method for preparing a composite material for removing inhibitors of acid hydrolysis and fermentation of agricultural and forestry fibers according to claim 1, characterized in that: In the step (1), the mass ratio of the bamboo residue to the phosphoric acid solution is 1:0.1-0.3; and the bamboo residue is soaked in the phosphoric acid solution for 2-12 hours.

3. The method for preparing a composite material for removing inhibitors of acid hydrolysis and fermentation of agricultural and forestry fibers according to claim 1, characterized in that: The bamboo residues in step (1) include bamboo processing residues and bamboo shoot shells; the particle size after crushing and screening is 0.02-2 mm; the solid content of the prepared phosphoric acid mixed slurry containing bamboo residues is 12%-22%; the pH of the phosphoric acid mixed slurry containing bamboo residues is 1.5-3.

5.

4. The method for preparing a composite material for removing inhibitors of acid hydrolysis and fermentation of agricultural and forestry fibers according to claim 1, characterized in that: The mass ratio of the phosphoric acid mixed slurry containing bamboo residues to calcium oxide or calcium hydroxide in step (1) is 1:0.1-0.5; the stirring temperature of the mixed slurry and calcium oxide is 60-100° C.; and the stirring time is 2-6 hours.

5. The method for preparing a composite material for removing inhibitors of acid hydrolysis and fermentation of agricultural and forestry fibers according to claim 1, characterized in that: The solid content of the mixed slurry containing bamboo residues and basic calcium phosphate prepared in the step (1) is 13% to 25%; the pH of the mixed slurry containing bamboo residues and basic calcium phosphate is 7.5 to 10.5; the rotation speed of the high-speed shearing treatment is 5000 to 20000 rpm; the shearing time is 5 to 30 minutes; the pressure of the high-pressure homogenization treatment is 15000 to 25000 PSI; and the homogenization treatment time is 2 to 15 minutes.

6. The method for preparing a composite material for removing inhibitors of acid hydrolysis and fermentation of agricultural and forestry fibers according to claim 1, characterized in that: The activation treatment conditions of step (2) are to increase the temperature to 340-420° C. at a heating rate of 5-15° C. / min and keep the temperature for 1-6 hours.

7. The method for preparing a composite material for removing inhibitors of acid hydrolysis and fermentation of agricultural and forestry fibers according to claim 1, characterized in that: In the step (3), the mass ratio of the bamboo-derived carbon-based material containing basic calcium phosphate to the reducing agent solution is 1:0.05-0.15; the type of the reducing agent is sodium sulfite or ammonium sulfite; and the mass fraction of the reducing agent solution is 1%-5%.

8. A composite material for removing inhibitors of acid hydrolysis and fermentation of agricultural and forestry fibers prepared by any one of the methods of claims 1 to 7.

9. Use of the composite material for removing inhibitors of acid hydrolysis and fermentation of agroforestry fibers according to claim 8 in removing inhibitors of acid hydrolysis and fermentation of agroforestry fibers.

10. Use of the composite material for removing inhibitors of acid hydrolysis and fermentation of agricultural and forestry fibers according to claim 9 in removing inhibitors of acid hydrolysis and fermentation of agricultural and forestry fibers, wherein the fiber acid comprises an inorganic acid, an organic acid or a mixed acid hydrolyzate.

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