Method for generating a cellulosic pulp
By treating peach residue with alkaline agents, organic solvents, and water-based bleaching, the problem of producing cellulose fibers from food industry waste has been solved, achieving efficient and environmentally friendly cellulose pulp extraction and providing a sustainable source of cellulose.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- LUCIA B PRIVATE CO
- Filing Date
- 2024-10-09
- Publication Date
- 2026-07-31
AI Technical Summary
Existing technologies are insufficient to effectively utilize food industry waste such as peach residue to produce high-value-added cellulose fibers, and traditional cellulose fiber production is overly reliant on forest resources, leading to resource shortages and environmental pressure.
Cellulose pulp was extracted by mixing peach residue with an alkaline aqueous solution, filtering, and then treating it with organic solvents and aqueous bleaching solutions. This method utilizes food industry waste as raw material, avoids additional pretreatment steps, and improves the purity and strength of the cellulose pulp.
It enables the efficient extraction of high-value-added cellulose pulp from food industry waste, reduces water and energy consumption, lowers dependence on forest resources, provides a sustainable source of cellulose, and reduces environmental pressure.
Smart Images
Figure CN122497788A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of producing cellulose slurries. Background Technology
[0002] Natural fibers cannot meet the raw material demands of the modern textile industry because production cycles are fixed, reserves are limited, and large amounts of arable land must be used for industrial crops such as cotton. Synthetic fibers meet additional demands and hold the largest market share, but they are petrochemical products derived from non-renewable raw materials.
[0003] Man-made cellulose fibers, made from regenerated cellulose, are another option, and their market share is steadily increasing. Currently, cellulose fibers are primarily produced from wood, with less than 1% produced from recycled or alternative raw materials. Using agricultural crops instead of wood has the advantage of reducing deforestation, while utilizing food industry waste allows for recycling, resulting in high-value-added products. Summary of the Invention
[0004] The method for generating cellulose pulp according to the present invention comprises: mixing an organic material obtained from peaches with an aqueous solution to form a first suspension, wherein the aqueous solution is an alkaline solution; filtering the first suspension to extract a first solid from the first suspension; mixing the first solid with an organic solvent to form a second suspension; filtering the second suspension to extract a second solid from the second suspension; applying an aqueous bleaching solution to the second solid to form a third suspension; and filtering the third suspension to extract cellulose pulp from the third suspension.
[0005] The method involves mixing organic material obtained from peaches with an aqueous solution to form a first suspension, wherein the aqueous solution is an alkaline solution.
[0006] The organic material obtained from peaches is preferably peach residue from the food industry. Specifically, the organic material is dried, de-walnuted waste. The organic material obtained from peaches is preferably peach residue without pits. Optionally, the method includes removing the pits and extracting peach juice from the peaches to form the organic material.
[0007] Adding an aqueous solution to organic materials helps remove hemicellulose from waste. This mechanism can be divided into two consecutive stages. First, the physical interaction between cellulose and the aqueous sodium hydroxide solution causes the fibers of the organic material to swell. Second, this causes the hemicellulose to diffuse from the inside of the fiber to the outside through swelling pores in the fiber wall and transfer into the aqueous solution.
[0008] The organic material obtained from peaches is mixed with an aqueous solution for alkali treatment. During alkali treatment, cellulose undergoes a stripping reaction, which reduces its degree of polymerization and produces low slurry strength. This is an end-degradation process in which reducing end groups are cleaved from the cellulose chains, resulting in soluble degradation products such as isopyringic acid. This phenomenon is mitigated using moderate temperatures and alkali concentrations.
[0009] The method includes filtering a first suspension to extract a first solid from the first suspension. The aqueous solution is removed from the process by filtration.
[0010] This method involves mixing a first solid with an organic solvent to form a second suspension. The first solid has already undergone a swelling process upon the addition of an aqueous solution. The application of the organic solvent facilitates further purification to remove unwanted substances. The use of the organic solvent demonstrates the ability to remove lignin and hemicellulose under mild conditions without significant cellulose degradation. The rate of delignification under acidic conditions is controlled by α-ether cleavage, while β-ether cleavage is more likely to occur in more acidic systems. Cellulose degradation is a result of acid hydrolysis, in which H+ ions permeate into cellulose molecules and attach to β-1,4-glycosidic bonds, thereby shortening the cellulose chain.
[0011] The method includes filtering a second suspension to extract a second solid from the second suspension. The organic solvent is removed during the filtration process.
[0012] The method involves applying an aqueous bleaching solution to a second solid to form a third suspension. Treatment with the aqueous bleaching solution further promotes the delignination of the pulp. Furthermore, hemicellulose, resulting from cellulose decomposition occurring in previous steps of the process, is removed.
[0013] The method includes filtering a third suspension to extract a cellulose slurry from the third suspension. Preferably, the cellulose slurry is extracted from the third suspension by filtering the third suspension.
[0014] The advantage of the method according to the invention is that it allows the use of peach residue directly from the food industry (and especially canneries and juice factories), with the only pretreatment being drying, which can be omitted since drying is done to facilitate the transport of raw materials.
[0015] In this way, a circular economy is achieved by utilizing waste primarily from the peach industry and transforming it into high-value-added raw materials. Producing 1 kg of cotton requires 10,000 liters of water, meaning that manufacturing one cotton T-shirt requires approximately 2,700 liters of water. In this invention, the use of waste streams demonstrates that there is no water footprint at the planting stage.
[0016] This method adds value to peach waste and transforms it into a valuable commodity. This is achieved through an environmentally friendly process. In the context of climate change, the transition to sustainable production is becoming an inevitable trend. The increase in modern agricultural activities generates a large amount of waste, placing greater pressure on public waste management systems. Agricultural waste, such as peach waste, is an annually renewable and low-cost source of natural cellulose fibers. Due to the dwindling supply of natural raw materials in the textile industry, utilizing agricultural waste fibers is an attractive option to make full use of the large quantities of natural plant fibers currently being discarded. Cellulose crops such as cotton, due to their higher economic value, are crowding out food crops. Therefore, fashion created using the method according to the invention may be considered to exacerbate food shortages.
[0017] The dependent claims define advantageous embodiments of the invention.
[0018] Preferably, the aqueous solution contains 2% w / v to 3% w / v sodium hydroxide. The addition of sodium hydroxide helps to remove hemicellulose from organic materials.
[0019] Preferably, the mixing of the organic material with the aqueous solution and / or the mixing of the first solid with the organic solvent are carried out at a temperature between 75°C and 85°C. This improves the slurry strength of the cellulose slurry.
[0020] Preferably, the mixing of the organic material with the aqueous solution and / or the mixing of the first solid with the organic solvent is carried out under continuous mechanical stirring. This results in a more uniform cellulose slurry structure.
[0021] Preferably, the mixing of the organic material with the aqueous solution and / or the mixing of the first solid with the organic solvent is carried out for at least 60 minutes, preferably at least 90 minutes. This ensures optimal removal of hemicellulose from the organic material.
[0022] Preferably, a first washing process is applied to the first solid extracted from the first suspension, wherein the first washing process preferably includes rinsing the first solid with water. This ensures the removal of aqueous solution from the first solid.
[0023] Preferably, the organic solvent is a combination of 85% v / v formic acid and 80% v / v acetic acid added in equal proportions. Preferably, the volume ratio between the first solid and the organic solvent is in the range of 1:6 to 1:12. This avoids damage to the fibers of the cellulose pulp while ensuring the removal of all unwanted substances from the first solid.
[0024] Preferably, a second washing process is applied to the second solid extracted from the second suspension, wherein the second washing process preferably includes rinsing the second solid with water. This ensures the removal of organic solvents from the second solid.
[0025] Preferably, the aqueous bleaching solution is an aqueous hydrogen peroxide solution. In the alkaline solution, hydrogen peroxide is a strong reducing agent and also generates oxygen. Sodium hydroxide is used as a solubilizer to extract modified lignin fragments, while hydrogen peroxide and the oxygen generated by the decomposition of hydrogen peroxide erode and fragment the residual lignin. Hemicellulose, resulting from cellulose decomposition in a previous step of the process, can be removed via the same mechanism. Hydrogen peroxide bleaching is preferably carried out with an alkaline source to generate active perhydroxyl anions (HOO-) and perhydroxyl radicals, which are considered intermediates in the brightening reaction of cellulose-based products. Hydrogen peroxide decomposes to form water and oxygen, so no bleaching agent residues or organochlorine byproducts are found in the final product.
[0026] Preferably, when applying the aqueous hydrogen peroxide solution to the second solid, twenty volumes of the aqueous hydrogen peroxide solution are applied to one volume of the second solid, wherein the aqueous hydrogen peroxide solution has a concentration of 0.5% v / v to 3.5% v / v. This avoids damage to the fibers of the cellulose pulp while ensuring the removal of all unwanted substances from the first solid.
[0027] Preferably, the aqueous hydrogen peroxide solution contains sodium hydroxide and has a pH level between 10 and 12.
[0028] Preferably, a third washing process is applied to the cellulose slurry extracted from the third suspension, wherein the third washing process preferably includes rinsing the cellulose slurry with water. This ensures the removal of the aqueous bleach solution from the second solid.
[0029] Preferably, the method includes drying a cellulose slurry.
[0030] The method for producing textiles according to the invention includes generating a cellulose slurry using the method for generating a cellulose slurry according to the invention, and preferably includes mixing the cellulose slurry with a wood- or cotton-based cellulose slurry. The step of mixing the cellulose slurry with a wood- or cotton-based cellulose slurry strengthens the structure of the textile. Attached Figure Description
[0031] Figure 1 A flowchart of the method according to the present invention is shown. Detailed Implementation
[0032] Figure 1 A flowchart of a method 100 for generating cellulose slurry according to an embodiment of the present invention is shown.
[0033] The objective of Method 100 is to extract the cellulose contents present in the natural microenvironment of unremoved walnut waste in the form of pulp fibers. This is achieved by treatment with hot water solutions that remove soluble components, including sugars, phenolic components, and soluble polysaccharides such as pectin.
[0034] In the first step 101, the organic material obtained from the peaches is mixed with an aqueous solution to form a first suspension, wherein the aqueous solution is an alkaline solution. The organic material is dried walnut waste. The aqueous solution contains 2% w / v to 3% w / v sodium hydroxide.
[0035] The dried walnut waste was mixed with an aqueous solution containing 2% w / v to 3% w / v NaOH (sodium hydroxide) in a suitable stainless steel container, which was heated at 80°C ± 5°C and maintained for 90 minutes with continuous mechanical stirring. Therefore, the mixing of the organic material with the aqueous solution in the first step 101 was carried out at a temperature between 75°C and 85°C with continuous mechanical stirring, wherein the mixing was carried out for at least 60 minutes, and here for 90 minutes.
[0036] In the first example, 200g of dried peach waste from the juice industry was used as the organic material. It was mixed with 2.5% w / v NaOH at a solids (peach waste) to solvent ratio of 1:20 and carried out in a first bath at 80℃±5℃ for 90 minutes.
[0037] In a second step 102, performed after the first step 101, the first suspension is filtered to extract the first solid from the first suspension. The second step 102 also includes a first washing process 102a. The first washing process 102a is applied to the first solid extracted from the first suspension, wherein the first washing process includes rinsing the first solid with water. Thus, the first suspension is filtered and the resulting first solid is washed with tap water to remove all remaining NaOH. Filtration is preferably performed using a series of sieves with progressively smaller mesh sizes (mesh openings ranging from 1.6 mm to 36 μm). Alternatively, other methods such as bag filters, filter presses, and belt filter presses can be used. In this embodiment, the first solid is washed and filtered multiple times, preferably three times.
[0038] In the third step 103, performed after the second step 102, the first solid is mixed with an organic solvent to form a second suspension. The organic solvent is a combination of 85% v / v formic acid and 80% v / v acetic acid added in equal proportions. That is, equal volumes of 85% v / v acid and 80% v / v acetic acid are combined to form the organic solvent.
[0039] The first solid is treated with an organic solvent, which is a combination of 85% v / v formic acid and 80% v / v acetic acid added in equal proportions. The second suspension is heated at 80°C ± 5°C and maintained at that temperature for 90 minutes with continuous mechanical stirring. The ratio of the first solid (peach waste) to the organic solvent is preferably in the range of 1:6 to 1:12. Therefore, the organic solvent is a combination of 85% v / v formic acid and 80% v / v acetic acid added in equal proportions, wherein the volume ratio or weight ratio between the first solid and the organic solvent is in the range of 1:6 to 1:12.
[0040] The first solid and the organic solvent are mixed in a suitable stainless steel container, which is heated at 80°C ± 5°C and maintained under continuous mechanical stirring for 90 minutes. Therefore, in the third step 103, the mixing of the first solid and the organic solvent is carried out at a temperature between 75°C and 85°C and under continuous mechanical stirring, wherein the mixing takes place for at least 60 minutes, and in this case, for 90 minutes.
[0041] In the first example, 85% v / v formic acid and 80% v / v acetic acid were mixed in a 1:1 ratio, wherein the ratio of solid to solvent was 1:6, and the mixture was carried out in a second bath at 80°C ± 5°C for 90 minutes.
[0042] In the fourth step 104, performed after the second step 103, the second suspension is filtered to extract the second solid from the second suspension. The fourth step 104 also includes a second washing process 104a. The second washing process 104a is applied to the second solid extracted from the suspension, wherein the second washing process 104a includes rinsing the second solid with water. Therefore, the second suspension is filtered and the resulting second solid is washed with tap water to remove all remaining organic solvents. Filtration is preferably performed using a series of sieves with progressively smaller mesh sizes (mesh openings ranging from 1.6 mm to 36 μm). Alternatively, other methods such as bag filters, filter presses, and belt filter presses can be used. In this embodiment, the second first solid is washed and filtered multiple times, preferably three times. The second suspension is filtered and the resulting second solid is washed with tap water until all acid is removed.
[0043] In step 105, following step 104, an aqueous bleaching solution is applied to the second solid to form a third suspension. The aqueous bleaching solution is an aqueous hydrogen peroxide solution. When applying the aqueous hydrogen peroxide solution to the second solid, twenty volumes of the solution are applied to one volume of the second solid, wherein the aqueous hydrogen peroxide solution has a concentration of 0.5% v / v to 3.5% v / v. The aqueous hydrogen peroxide solution contains sodium hydroxide and has a pH level between 10 and 12. Thus, the second solid is further purified and bleached with 20 volumes of an aqueous hydrogen peroxide solution with a concentration of 0.5% v / v to 3.5% v / v, which contains NaOH to adjust the pH level to between 10 and 12.
[0044] Note that alternative reagents can be used as aqueous bleaching solutions. Exemplary reagents are sodium hypochlorite (NaOCl), which can be used at room temperature, sodium chlorite (NaClO2), which can be used at 80°C ± 5°C, and ozone. This list is not exhaustive. Enzymatic treatment with cellulase is also possible, according to the literature. Hydrogen peroxide has the advantage of leaving no residual concentration, but it is susceptible to the presence of transition metals, pH levels, and high temperatures.
[0045] In the first example, 0.5% v / v H2O2 containing 4 g / L NaOH was applied at a solid-to-solvent ratio of 1:20 and kept in a third bath at 80 °C ± 5 °C for 90 minutes.
[0046] In the sixth step 106, performed after the fifth step 105, the third suspension is filtered to extract the cellulose slurry from the third suspension. The sixth step 106 also includes a third washing process 106a. The third washing process 106a is applied to the cellulose slurry extracted from the third suspension, wherein the third washing process 106a includes rinsing the cellulose slurry with water. Therefore, the third suspension is filtered and the resulting cellulose slurry is washed with tap water to remove all remaining aqueous bleach solution. Filtration is preferably performed using a series of sieves with progressively smaller mesh sizes (mesh openings ranging from 1.6 mm to 36 μm). Alternatively, other methods such as bag filters, filter presses, and belt filter presses can be used. In this embodiment, the cellulose slurry is washed and filtered multiple times, preferably three times. The cellulose slurry is filtered and the resulting cellulose slurry is washed with tap water until all aqueous bleach solution is removed.
[0047] In step 7, 107, which follows step 6, the washed cellulose slurry is dried. Preferably, the cellulose slurry is dried at 60°C until it reaches a stable weight, preferably within 48 hours.
[0048] Method 100 produces a cellulose pulp with an α-cellulose content greater than 92% and a degree of polymerization greater than 510. The overall yield of this process, starting from walnut waste, exceeds 11%. Through each step of filtration, large foreign matter and sediments, such as peach pits that were not extracted during industrial peach processing, are removed.
[0049] In the first example, the cellulose slurry was dried at 60°C for 48 hours until it reached a stable weight. This method yielded a yield of 11.6%, a DP of 567, and an α-cellulose content of 94.9% in the cellulose slurry.
[0050] The cellulose pulp of the present invention can be used in the production of textiles, preferably when mixed with a dissolving pulp from a conventional plant-based source, such as wood and / or cotton lint. The production of textiles can be accomplished using a method for producing yarn, which includes generating a cellulose pulp using the method 100 described above and subsequently mixing the cellulose pulp with a wood- or cotton-based cellulose pulp.
Claims
1. A method (100) for producing cellulose pulp, the method comprising: Organic material obtained from peaches is mixed with an aqueous solution (101) to form a first suspension, wherein the aqueous solution is an alkaline solution; Filter (102) the first suspension to extract the first solid from the first suspension; The first solid is mixed with an organic solvent (103) under continuous mechanical stirring to form a second suspension; Filter (104) the second suspension to extract the second solid from the second suspension; A (105) aqueous bleaching solution was applied to the second solid to form a third suspension; as well as Filter (106) the third suspension to extract the cellulose slurry from the third suspension.
2. The method (100) according to claim 1, wherein the aqueous solution contains 2% w / v to 3% w / v sodium hydroxide.
3. The method (100) according to any one of the preceding claims, wherein the mixing (101) of the organic material with the aqueous solution and / or the mixing (103) of the first solid with the organic solvent is carried out at a temperature in the range of 75°C to 85°C.
4. The method (100) according to any one of the preceding claims, wherein the mixing (101) of the organic material with the aqueous solution and / or the mixing (103) of the first solid with the organic solvent is carried out for at least 60 minutes.
5. The method (100) according to any one of the preceding claims, wherein the mixing (101) of the organic material with the aqueous solution and / or the mixing (103) of the first solid with the organic solvent is carried out for at least 60 minutes, preferably at least 90 minutes.
6. The method (100) according to any one of the preceding claims, wherein the first solid extracted from the first suspension is subjected to a first washing process (102a), wherein the first washing process preferably includes rinsing the first solid with water.
7. The method (100) according to any one of the preceding claims, wherein the organic solvent is preferably a combination of 85% v / v formic acid and 80% v / v acetic acid added in equal proportions.
8. The method (100) according to any one of the preceding claims, wherein the volume ratio between the first solid and the organic solvent is in the range of 1:6 to 1:
12.
9. The method (100) according to any one of the preceding claims, wherein the second solid extracted from the second suspension is subjected to a second washing (104a) process, wherein the second washing process preferably includes rinsing the second solid with water.
10. The method (100) according to any one of the preceding claims, wherein the aqueous bleaching solution is an aqueous hydrogen peroxide solution.
11. The method (100) according to claim 10, wherein when applying the aqueous hydrogen peroxide solution to the second solid, twenty volumes of the aqueous hydrogen peroxide solution are applied to one volume of the second solid, wherein the aqueous hydrogen peroxide solution has a concentration of 0.5% v / v to 3.5% v / v.
12. The method (100) according to any one of claims 10 and 11, wherein the aqueous hydrogen peroxide solution contains sodium hydroxide and has a pH level between 10 and 12.
13. The method (100) according to any one of the preceding claims, wherein the cellulose slurry extracted from the third suspension is subjected to a third washing process (106a), wherein the third washing process preferably includes rinsing the cellulose slurry with water.
14. The method (100) according to any one of the preceding claims, wherein the method comprises drying the cellulose slurry.
15. A method for generating a cellulose pulp suitable for use in the production of textiles, the method comprising: Cellulose slurry is produced using the method (100) according to any one of the preceding claims; as well as The cellulose pulp is mixed with a wood- or cotton-based cellulose pulp.