A method for detoxifying resin from recycled wood fiber hydrolysate

Abstract

This invention discloses a method for detoxifying resin from regenerated lignocellulosic hydrolysate, belonging to the field of ionomer resin regeneration technology. The method first detoxifies the lignocellulosic hydrolysate with resin, then separates the detoxified hydrolysate from the poisoned resin, and finally regenerates the poisoned resin using a regenerating agent, namely hydrogen peroxide and sodium hydroxide, for reuse. This invention restores the adsorption efficiency of the regenerated resin for acetic acid and identifiable total inhibitors to 86.97% and 80.49%, respectively, without damaging the basic resin framework and functional groups. Furthermore, the resin can be recycled three times, significantly improving the overall economic and environmental benefits of the process.

Description

Technical Field

[0001] This invention belongs to the field of ion exchange resin regeneration technology, specifically relating to a method for detoxifying lignocellulosic hydrolysate resin. Background Technology

[0002] Lignocellulosic biomass, as a potential source of biofuels and bioproducts, is of great significance for promoting the development of the bioeconomy. Converting lignocellulosic biomass into high-value-added products requires a pretreatment step to break it down into readily available monosaccharides and other compounds. However, the pretreatment process generates toxic compounds, severely impacting subsequent microbial fermentation and enzymatic hydrolysis. Therefore, detoxifying the lignocellulosic hydrolysate before further processing is a crucial step.

[0003] Ion exchange resins, as a commonly used and highly efficient detoxification technology, have been widely applied in various industrial fields, achieving significant economic benefits. Resins offer advantages in industrial applications, including high processing capacity, high efficiency, and high selectivity. Most importantly, resins can be cleaned and regenerated using appropriate methods, enabling recycling and reducing the operating costs and environmental impact of the detoxification process. Therefore, resin-based detoxification technology is a highly promising approach applicable to the high-value utilization of lignocellulosic hydrolysates.

[0004] Ion exchange resins can effectively remove weak acids, furans, and phenolic inhibitors from lignocellulosic hydrolysates with minimal impact on sugar content. However, due to the complex composition of lignocellulosic hydrolysates, which contain not only fermentable sugars and inhibitors but also many pigments and plant proteins, the detoxified resin suffers from severe multi-contamination, making the regeneration of poisoned resin a difficult and urgent problem. Currently, research on the regeneration of detoxified resins from lignocellulosic hydrolysates is limited, with most studies focusing only on inhibitor removal rates. Typically, the regenerators used for resin regeneration are expensive, hazardous, and difficult-to-recover organic solvents or strong acids / bases. Therefore, developing an environmentally friendly and economical resin regeneration method is urgently needed. Summary of the Invention

[0005] To address the aforementioned problems in the existing technology, the technical problem to be solved by the present invention is to provide a method for detoxifying resin from regenerated wood fiber hydrolysate. By combining the green oxidant hydrogen peroxide and low-concentration sodium hydroxide, the adsorption efficiency of the detoxified resin is significantly restored without destroying the basic framework and functional groups of the resin, thereby improving the economic and environmental benefits of high-value utilization of wood fiber hydrolysate.

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

[0007] A method for detoxifying resin from regenerated wood fiber hydrolysate involves first detoxifying the wood fiber hydrolysate with resin, then separating the detoxified hydrolysate from the poisoned resin, and finally regenerating the poisoned resin using a regenerating agent for recycling. The regenerating agent is hydrogen peroxide and sodium hydroxide.

[0008] Furthermore, the resin is a gel-type anion exchange resin 335.

[0009] Furthermore, the amount of the gel-type anion exchange resin 335 used is 5% to 20% of the mass of the hydrolysate.

[0010] Furthermore, the concentration of hydrogen peroxide is 0.5% to 5%, and the mass ratio of hydrogen peroxide to poisoned resin is 2:1 to 6:1.

[0011] Furthermore, the hydrogen peroxide regeneration time is 4–12 hours.

[0012] Furthermore, the concentration of the sodium hydroxide is 1 mol / L to 4 mol / L.

[0013] Furthermore, the mass ratio of sodium hydroxide to poisoned resin is 2:1 to 6:1.

[0014] Furthermore, the sodium hydroxide regeneration time is 4–12 hours.

[0015] Furthermore, the use of the regenerant must be carried out in a shaking reaction system at a temperature of 25–35°C and a rotation speed of 100–150 rpm.

[0016] Furthermore, the lignocellulose hydrolysate is a hydrolysate obtained by acid hydrolysis of corn cob sulfuric acid hydrolysate and agricultural and forestry waste rich in hemicellulose.

[0017] Beneficial effects: Compared with the prior art, the advantages of this invention are:

[0018] (1) The present invention uses a combination of green oxidant hydrogen peroxide and low-concentration sodium hydroxide to regenerate the detoxified resin of wood fiber hydrolysate, which is a relatively effective green regeneration method and provides a new approach for resin regeneration in industry.

[0019] (2) The present invention uses hydrogen peroxide to regenerate wood fiber hydrolysate to detoxify resin, avoiding the use of expensive, dangerous and difficult-to-recycle organic solvents or strong acids / bases, and greatly reducing environmental pollution.

[0020] (3) The present invention uses hydrogen peroxide to regenerate wood fiber hydrolysate to detoxify resin, which can restore the adsorption efficiency of the resin for acetic acid and total identifiable inhibitors to 86.97% and 80.49% respectively without destroying the basic skeleton and functional groups of the resin. The resin can be recycled three times, realizing the recycling of the resin, effectively reducing the process cost, and achieving the goal of sustainable development. Attached Figure Description

[0021] Figure 1 These are scanning electron microscope images of fresh resin, poisoned resin, and regenerated resin in Example 1 of the present invention. Detailed Implementation

[0022] To make the above-mentioned objectives, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to specific examples.

[0023] The corn cob sulfuric acid hydrolysate used in the following examples was provided by Shanghai Ego Zhuoxin Technology Co., Ltd. It was obtained by mixing corn cobs with 1% sulfuric acid at a solid-liquid ratio of 1:5 and treating at 150°C for 30 minutes. Its main sugar and inhibitor contents are as follows: 56.84 g / L xylose, 7.85 g / L glucose, 6.03 g / L arabinose, 0.94 g / L formic acid, 9.61 g / L acetic acid, 0.69 g / L levulinic acid, 0.26 g / L 5-hydroxymethylfurfural, and 3.11 g / L furfural. The gel-type anion exchange resin 335 used was sourced from Shanghai Huazhen Technology Co., Ltd.

[0024] Example 1

[0025] A method for detoxifying resin from recycled wood fiber hydrolysate:

[0026] (1) 5g of gel-type anion exchange resin 335 and 50ml of corn cob sulfuric acid hydrolysate were placed in a 250ml glass beaker and statically detoxified in a constant temperature water bath at 30℃ and 100rpm. After 2 hours of reaction, the contents of the main sugars and inhibitors in the hydrolysate were: 47.68g / L xylose, 6.18g / L glucose, 5.16g / L arabinose, 0g / L formic acid, 1.46g / L acetic acid, 0g / L levulinic acid, 0.07g / L 5-hydroxymethylfurfural and 0.87g / L furfural. The removal rate of acetic acid was 84.8%.

[0027] (2) Then, the poisoned resin and hydrolysate are separated by a filter bag. The poisoned resin is then mixed with 5% hydrogen peroxide at a mass ratio of 1:2 and regenerated at room temperature for 5 hours at a speed of 120 rpm. After the reaction is completed, the resin is separated by a filter bag and mixed with 1 mol / L sodium hydroxide at a mass ratio of 1:2. The mixture is then regenerated at room temperature for another 4 hours at a speed of 120 rpm. Finally, the regenerated resin is obtained.

[0028] (3) The regenerated resin was used to detoxify fresh corn cob sulfuric acid hydrolysate. The reaction conditions were the same as above. After 2 hours of reaction, the contents of the main sugars and inhibitors in the hydrolysate were: 47.81 g / L xylose, 6.01 g / L glucose, 5.13 g / L arabinose, 0 g / L formic acid, 2.52 g / L acetic acid, 0.37 g / L levulinic acid, 0.23 g / L 5-hydroxymethylfurfural and 2.14 g / L furfural. The removal rate of acetic acid was 73.8%.

[0029] Figure 1 The images show scanning electron microscope (SEM) images of fresh resin, poisoned resin, and regenerated resin in Example 1 of this invention. As can be seen from the images, the surface of fresh resin (a) is smooth, while the surface of poisoned resin (b) is covered with impurities and is severely contaminated. After treatment with hydrogen peroxide and sodium hydroxide, the impurities on the surface of the regenerated resin (c) are basically removed, and its adsorption capacity is restored, demonstrating the feasibility and effectiveness of this regeneration method.

[0030] Table 1. Content of inhibitors in hydrolysate of fresh corn cob sulfuric acid hydrolysate prepared in Example 1 after resin circulation detoxification.

[0031]

[0032]

[0033] Example 2

[0034] A method for detoxifying resin from recycled wood fiber hydrolysate:

[0035] (1) 5g of gel-type anion exchange resin 335 and 50ml of corn cob sulfuric acid hydrolysate were placed in a 250ml glass beaker and statically detoxified in a constant temperature water bath at 30℃ and 100rpm. After 2 hours of reaction, the contents of the main sugars and inhibitors in the hydrolysate were: 47.68g / L xylose, 6.18g / L glucose, 5.16g / L arabinose, 0g / L formic acid, 1.46g / L acetic acid, 0g / L levulinic acid, 0.07g / L 5-hydroxymethylfurfural and 0.87g / L furfural. The removal rate of acetic acid was 84.8%.

[0036] (2) Then, the poisoned resin and hydrolysate are separated by a filter bag. The poisoned resin is then mixed with 5% hydrogen peroxide at a mass product ratio of 1:2 and regenerated at room temperature for 5 hours at a speed of 120 rpm. After the reaction, the resin is separated by a filter bag and mixed with 5% hydrogen peroxide at a mass product ratio of 1:2 again and regenerated at room temperature for 5 hours at a speed of 120 rpm. After the reaction, the resin is separated by a filter bag and mixed with 1 mol / L sodium hydroxide at a mass product ratio of 1:2 and regenerated at room temperature for 4 hours at a speed of 120 rpm. Finally, the regenerated resin is obtained.

[0037] (3) The regenerated resin was used to detoxify fresh corn cob sulfuric acid hydrolysate. The reaction conditions were the same as above. After 2 hours of reaction, the contents of the main sugars and inhibitors in the hydrolysate were: 48.73 g / L xylose, 6.07 g / L glucose, 5.14 g / L arabinose, 0 g / L formic acid, 2.14 g / L acetic acid, 0.30 g / L levulinic acid, 0.25 g / L 5-hydroxymethylfurfural and 2.15 g / L furfural. The removal rate of acetic acid was 77.7%.

[0038] Table 2. Content of inhibitors in hydrolysate of fresh corn cob sulfuric acid hydrolysate prepared in Example 2 after resin circulation detoxification.

[0039]

[0040] Example 3

[0041] A method for detoxifying resin from recycled wood fiber hydrolysate:

[0042] (1) 5g of gel-type anion exchange resin 335 and 50ml of corn cob sulfuric acid hydrolysate were placed in a 250ml glass beaker and statically detoxified in a constant temperature water bath at 30℃ and 100rpm. After 2 hours of reaction, the contents of the main sugars and inhibitors in the hydrolysate were: 47.68g / L xylose, 6.18g / L glucose, 5.16g / L arabinose, 0g / L formic acid, 1.46g / L acetic acid, 0g / L levulinic acid, 0.07g / L 5-hydroxymethylfurfural and 0.87g / L furfural. The removal rate of acetic acid was 84.8%.

[0043] (2) Then, the poisoned resin and hydrolysate are separated by a filter bag. The poisoned resin is then mixed with 5% hydrogen peroxide at a mass product ratio of 1:2 and regenerated at room temperature for 12 hours at a speed of 120 rpm. After the reaction, the resin is separated by a filter bag and mixed with 5% hydrogen peroxide at a mass product ratio of 1:2. The mixture is then regenerated at room temperature for 12 hours at a speed of 120 rpm. After the reaction, the resin is separated by a filter bag and mixed with 1 mol / L sodium hydroxide at a mass product ratio of 1:2. The mixture is then regenerated at room temperature for 4 hours at a speed of 120 rpm. Finally, the regenerated resin is obtained.

[0044] (3) The regenerated resin was used to detoxify fresh corn cob sulfuric acid hydrolysate. The reaction conditions were the same as above. After 2 hours of reaction, the contents of the main sugars and inhibitors in the hydrolysate were: 44.31 g / L xylose, 5.25 g / L glucose, 4.17 g / L arabinose, 0.88 g / L formic acid, 5.60 g / L acetic acid, 0.52 g / L levulinic acid, 0.24 g / L 5-hydroxymethylfurfural and 2.08 g / L furfural. The removal rate of acetic acid was 41.7%.

[0045] Table 3. Content of inhibitors in hydrolysate of fresh corn cob sulfuric acid hydrolysate prepared in Example 3 after resin circulation detoxification.

[0046]

[0047] Tables 1-3 show the content of inhibitors in the hydrolysate of fresh corn cob sulfuric acid hydrolysate after the resin was circulated and detoxified in Examples 1-3 of this invention. As can be seen from the table, with appropriate methods, the resin can still adsorb the acetic acid content in the hydrolysate to below 5 g / L after three cycles of use. Below 5 g / L is a safe concentration with minimal impact on microorganisms that we have verified in the laboratory. However, under unsuitable regeneration conditions (Example 3), the resin will lose its selective adsorption or even its adsorption capacity. Therefore, selecting appropriate regeneration conditions is crucial for the regeneration of the resin.

[0048] Example 4

[0049] A method for detoxifying resin from recycled wood fiber hydrolysate:

[0050] (1) 5g of anion exchange resin 335 and 50ml of corn cob sulfuric acid hydrolysate were placed in a 250ml glass beaker and statically detoxified in a constant temperature water bath at 30℃ and 100rpm. After 2 hours of reaction, the contents of the main sugars and inhibitors in the hydrolysate were: 47.68g / L xylose, 6.18g / L glucose, 5.16g / L arabinose, 0g / L formic acid, 1.46g / L acetic acid, 0g / L levulinic acid, 0.07g / L 5-hydroxymethylfurfural and 0.87g / L furfural. The removal rate of acetic acid was 84.8%.

[0051] (2) Solid-liquid separation was performed using a filter bag. The poisoned resin was mixed with 0.5% hydrogen peroxide at a mass product ratio of 1:2 and regenerated at room temperature for 12 hours at a rotation speed of 150 rpm. After the reaction, the resin was separated using a filter bag and mixed again with 0.5% hydrogen peroxide at a mass product ratio of 1:2. The mixture was regenerated at room temperature for 12 hours at a rotation speed of 150 rpm. After the reaction, the resin was separated using a filter bag and mixed with 1 mol / L sodium hydroxide at a mass product ratio of 1:2. The mixture was regenerated at room temperature for 4 hours at a rotation speed of 150 rpm. Finally, the regenerated resin was obtained.

[0052] (3) The regenerated resin was used to detoxify fresh corn cob sulfuric acid hydrolysate. The reaction conditions were the same as above. After 2 hours of reaction, the contents of the main sugars and inhibitors in the hydrolysate were: 47.27 g / L xylose, 5.56 g / L glucose, 4.40 g / L arabinose, 0.86 g / L formic acid, 2.98 g / L acetic acid, 0.38 g / L levulinic acid, 0.22 g / L 5-hydroxymethylfurfural and 1.44 g / L furfural. The removal rate of acetic acid was 69.0%.

[0053] Example 5

[0054] A method for detoxifying resin from recycled wood fiber hydrolysate:

[0055] (1) 2.5g of anion exchange resin 335 and 50ml of corn cob sulfuric acid hydrolysate were placed in a 250ml glass beaker and statically detoxified in a constant temperature water bath at 30℃ and 100rpm. After 2 hours of reaction, the contents of the main sugars and inhibitors in the hydrolysate were: 53.84g / L xylose, 7.36g / L glucose, 5.98g / L arabinose, 0g / L formic acid, 2.76g / L acetic acid, 0g / L levulinic acid, 0.11g / L 5-hydroxymethylfurfural and 1.56g / L furfural. The removal rate of acetic acid was 71.3%.

[0056] (2) Solid-liquid separation was performed using a filter bag. The poisoned resin was mixed with 0.5% hydrogen peroxide at a mass product ratio of 1:2 and regenerated at room temperature for 12 hours at a rotation speed of 150 rpm. After the reaction was completed, the resin was separated using a filter bag and mixed with 1 mol / L sodium hydroxide at a mass product ratio of 1:2 and regenerated at room temperature for 4 hours at a rotation speed of 150 rpm. Finally, the regenerated resin was obtained.

[0057] (3) The regenerated resin was used to detoxify fresh corn cob sulfuric acid hydrolysate. The reaction conditions were the same as above. After 2 hours of reaction, the contents of the main sugars and inhibitors in the hydrolysate were: 54.11 g / L xylose, 7.60 g / L glucose, 6.18 g / L arabinose, 0.92 g / L formic acid, 4.88 g / L acetic acid, 0.43 g / L levulinic acid, 0.36 g / L 5-hydroxymethylfurfural and 2.97 g / L furfural. The removal rate of acetic acid was 49.2%.

[0058] Example 6

[0059] A method for detoxifying resin from recycled wood fiber hydrolysate:

[0060] (1) 5g of anion exchange resin 335 and 50ml of corn cob sulfuric acid hydrolysate were placed in a 250ml glass beaker and statically detoxified in a constant temperature water bath at 30℃ and 100rpm. After 2 hours of reaction, the contents of the main sugars and inhibitors in the hydrolysate were: 47.68g / L xylose, 6.18g / L glucose, 5.16g / L arabinose, 0g / L formic acid, 1.46g / L acetic acid, 0g / L levulinic acid, 0.07g / L 5-hydroxymethylfurfural and 0.87g / L furfural. The removal rate of acetic acid was 84.8%.

[0061] (2) Solid-liquid separation was performed using a filter bag. The poisoned resin was mixed with 3% hydrogen peroxide at a mass product ratio of 1:4 and regenerated at room temperature for 5 hours at a speed of 150 rpm. After the reaction was completed, the resin was separated using a filter bag and mixed with 1 mol / L sodium hydroxide at a mass product ratio of 1:4 and regenerated at room temperature for 4 hours at a speed of 150 rpm. Finally, the regenerated resin was obtained.

[0062] (3) The regenerated resin was used to detoxify fresh corn cob sulfuric acid hydrolysate. The reaction conditions were the same as above. After 2 hours of reaction, the contents of the main sugars and inhibitors in the hydrolysate were: 47.95 g / L xylose, 6.52 g / L glucose, 5.31 g / L arabinose, 0 g / L formic acid, 3.05 g / L acetic acid, 0.41 g / L levulinic acid, 0.26 g / L 5-hydroxymethylfurfural and 2.33 g / L furfural. The removal rate of acetic acid was 68.3%.

[0063] Example 7

[0064] A method for detoxifying resin from recycled wood fiber hydrolysate:

[0065] (1) 5g of anion exchange resin 335 and 50ml of corn cob sulfuric acid hydrolysate were placed in a 250ml glass beaker and statically detoxified in a constant temperature water bath at 30℃ and 100rpm. After 2 hours of reaction, the contents of the main sugars and inhibitors in the hydrolysate were: 47.68g / L xylose, 6.18g / L glucose, 5.16g / L arabinose, 0g / L formic acid, 1.46g / L acetic acid, 0g / L levulinic acid, 0.07g / L 5-hydroxymethylfurfural and 0.87g / L furfural. The removal rate of acetic acid was 84.8%.

[0066] (2) Solid-liquid separation was performed using a filter bag. The poisoned resin was mixed with 5% hydrogen peroxide at a mass product ratio of 1:4 and regenerated at room temperature for 5 hours at a speed of 150 rpm. After the reaction was completed, the resin was separated using a filter bag and mixed with 4 mol / L sodium hydroxide at a mass product ratio of 1:4. The mixture was then regenerated at room temperature for 12 hours at a speed of 150 rpm to obtain the regenerated resin.

[0067] (3) The regenerated resin was used to detoxify fresh corn cob sulfuric acid hydrolysate. The reaction conditions were the same as above. After 2 hours of reaction, the contents of the main sugars and inhibitors in the hydrolysate were: 47.75 g / L xylose, 6.12 g / L glucose, 5.14 g / L arabinose, 0 g / L formic acid, 2.38 g / L acetic acid, 0.32 g / L levulinic acid, 0.22 g / L 5-hydroxymethylfurfural and 2.08 g / L furfural. The removal rate of acetic acid was 75.2%.

[0068] Example 8

[0069] A method for detoxifying resin from recycled wood fiber hydrolysate:

[0070] (1) 5g of gel-type anion exchange resin 335 and 50ml of corn cob sulfuric acid hydrolysate were placed in a 250ml glass beaker and statically detoxified in a constant temperature water bath at 35℃ and 100rpm. After 2 hours of reaction, the contents of the main sugars and inhibitors in the hydrolysate were: 46.62g / L xylose, 6.15g / L glucose, 5.06g / L arabinose, 0g / L formic acid, 1.38g / L acetic acid, 0g / L levulinic acid, 0.06g / L 5-hydroxymethylfurfural and 0.67g / L furfural. The removal rate of acetic acid was 85.6%.

[0071] (2) Then, the poisoned resin and hydrolysate are separated by a filter bag. The poisoned resin is then mixed with 5% hydrogen peroxide at a mass ratio of 1:2 and regenerated at room temperature for 5 hours at a speed of 120 rpm. After the reaction is completed, the resin is separated by a filter bag and mixed with 1 mol / L sodium hydroxide at a mass ratio of 1:2. The mixture is then regenerated at room temperature for another 4 hours at a speed of 120 rpm. Finally, the regenerated resin is obtained.

[0072] (3) The regenerated resin was used to detoxify fresh corn cob sulfuric acid hydrolysate. The reaction conditions were the same as above. After 2 hours of reaction, the contents of the main sugars and inhibitors in the hydrolysate were: 47.51 g / L xylose, 5.91 g / L glucose, 5.02 g / L arabinose, 0 g / L formic acid, 2.12 g / L acetic acid, 0.31 g / L levulinic acid, 0.19 g / L 5-hydroxymethylfurfural and 1.96 g / L furfural. The removal rate of acetic acid was 77.9%.

[0073] Example 9

[0074] A method for detoxifying resin from recycled wood fiber hydrolysate:

[0075] The main sugars and inhibitors in the sulfuric acid hydrolysate of sugarcane bagasse used are as follows: 44.24 g / L xylose, 8.52 g / L glucose, 7.38 g / L arabinose, 0.64 g / L formic acid, 7.71 g / L acetic acid, 1.84 g / L levulinic acid, 0.85 g / L 5-hydroxymethylfurfural and 3.55 g / L furfural.

[0076] (1) 5g of anion exchange resin 335 and 50ml of sugarcane bagasse sulfuric acid hydrolysate were placed in a 250ml glass beaker and statically detoxified in a constant temperature water bath at 30℃ and 100rpm. After 2 hours of reaction, the contents of the main sugars and inhibitors in the hydrolysate were: 34.67g / L xylose, 7.06g / L glucose, 6.19g / L arabinose, 0g / L formic acid, 1.88g / L acetic acid, 0.34g / L levulinic acid, 0.33g / L 5-hydroxymethylfurfural and 1.12g / L furfural. The removal rate of acetic acid was 75.6%.

[0077] (2) Solid-liquid separation was performed using a filter bag. The poisoned resin was mixed with 0.5% hydrogen peroxide at a mass product ratio of 1:2 and regenerated at room temperature for 5 hours at a rotation speed of 150 rpm. After the reaction was completed, the resin was separated using a filter bag and mixed with 1 mol / L sodium hydroxide at a mass product ratio of 1:2 and regenerated at room temperature for 4 hours at a rotation speed of 150 rpm. Finally, the regenerated resin was obtained.

[0078] (3) The regenerated resin was used to detoxify fresh sugarcane bagasse sulfuric acid hydrolysate. The reaction conditions were the same as above. After 2 hours of reaction, the contents of the main sugars and inhibitors in the hydrolysate were: 35.52 g / L xylose, 7.25 g / L glucose, 6.51 g / L arabinose, 0 g / L formic acid, 2.24 g / L acetic acid, 0.41 g / L levulinic acid, 0.38 g / L 5-hydroxymethylfurfural and 1.25 g / L furfural. The removal rate of acetic acid was 70.9%.

[0079] Example 10

[0080] A method for detoxifying resin from recycled wood fiber hydrolysate:

[0081] (1) 2.5g of macroporous resin D303 and 50ml of corn cob sulfuric acid hydrolysate were placed in a 250ml glass beaker and statically detoxified in a constant temperature water bath at 30℃ and 100rpm. After 2 hours of reaction, the contents of the main sugars and inhibitors in the hydrolysate were: 42.06g / L xylose, 6.76g / L glucose, 5.19g / L arabinose, 0g / L formic acid, 6.11g / L acetic acid, 0.52g / L levulinic acid, 0.15g / L 5-hydroxymethylfurfural and 2.96g / L furfural. The removal rate of acetic acid was 36.4%.

[0082] (2) Solid-liquid separation is performed by filter bag. The poisoned resin is mixed with 5% hydrogen peroxide at a mass product ratio of 1:2 and regenerated at room temperature for 5 hours at a speed of 150 rpm. After the reaction is completed, the resin is separated by filter bag and mixed with 1 mol / L sodium hydroxide at a mass product ratio of 1:2 and regenerated at room temperature for 4 hours at a speed of 150 rpm. Finally, the regenerated resin is obtained.

[0083] (3) The regenerated resin was used to detoxify fresh corn cob sulfuric acid hydrolysate. The reaction conditions were the same as above. After 2 hours of reaction, the contents of the main sugars and inhibitors in the hydrolysate were: 43.78 g / L xylose, 6.96 g / L glucose, 5.58 g / L arabinose, 0 g / L formic acid, 6.88 g / L acetic acid, 0.56 g / L levulinic acid, 0.19 g / L 5-hydroxymethylfurfural and 2.99 g / L furfural. The removal rate of acetic acid was 28.4%.

[0084] Table 4. Comparison of inhibitor content in the hydrolysate of fresh corn cob sulfuric acid hydrolysate after detoxification with 335 resin and D303 resin

[0085]

[0086]

[0087] Table 4 compares the content of inhibitors in the hydrolysate of fresh corn cob sulfuric acid hydrolysate after detoxification with 335 resin and D303 resin. The detoxification and regeneration conditions were the same for both. The table shows that macroporous resin D303, compared to anion exchange resin 335, lacks selectivity, adsorbs significantly more sugars, and has a lower acetic acid removal rate, thus lacking application potential.

Claims

1. A method for detoxifying resin from recycled wood fiber hydrolysate, characterized in that, First, the lignocellulosic acid hydrolysate is detoxified with resin. Then, the detoxified hydrolysate is separated from the poisoned resin. The poisoned resin is then regenerated using a regenerating agent for recycling. The regenerating agent consists of hydrogen peroxide and sodium hydroxide. The resin is a gel-type anion exchange resin 335. The concentration of hydrogen peroxide is 0.5% to 5%, and the mass ratio of hydrogen peroxide to poisoned resin is 2:1 to 6:

1. The concentration of sodium hydroxide is 1 mol / L to 4 mol / L, and the mass ratio of sodium hydroxide to poisoned resin is 2:1 to 6:

1.

2. The method for detoxifying resin from recycled wood fiber hydrolysate according to claim 1, characterized in that, The amount of gel-type anion exchange resin 335 used is 5% to 20% of the mass of the hydrolysate.

3. The method for detoxifying resin from recycled wood fiber hydrolysate according to claim 1, characterized in that, The hydrogen peroxide regeneration time is 4~12h.

4. The method for detoxifying resin from recycled wood fiber hydrolysate according to claim 1, characterized in that, The sodium hydroxide regeneration time is 4~12h.

5. The method for detoxifying resin from recycled wood fiber hydrolysate according to claim 1, characterized in that, The use of the regenerant must be carried out in a shaking reaction system at a temperature of 25-35°C and a rotation speed of 100-150 rpm.

6. The method for detoxifying resin from recycled wood fiber hydrolysate according to claim 1, characterized in that, The lignocellulose hydrolysate is obtained by acid hydrolysis of corn cob sulfuric acid hydrolysate and agricultural and forestry waste rich in hemicellulose.

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