A ramie degumming method based on alcohol amine / betaine / water ternary homogeneous system

Abstract

This invention belongs to the field of natural fiber processing technology, specifically relating to a method for degumming ramie fibers based on a ternary homogeneous system of alkanolamine / betaine / water. The method includes ramie bast pretreatment, degumming treatment using the alkanolamine / betaine / water ternary homogeneous system, and post-treatment steps. In the ternary system, alkanolamine provides a mild alkaline environment to promote gum degradation, betaine enhances wetting and penetration properties, promotes gum detachment and dispersion, achieving integrated "penetration-degumming-dispersion," and water serves as a medium to form a stable homogeneous system, thereby achieving efficient and uniform removal of ramie gum. The pretreatment and the ternary homogeneous system degumming step work synergistically to promote degumming solution penetration and improve degumming efficiency. Compared with existing technologies, this invention has high degumming efficiency, minimal fiber damage, a simple process that does not require strong acids or alkalis, low residual gum rate, is environmentally friendly, and reduces costs. The resulting ramie fibers have good properties and significant industrial application value.

Description

Technical Field

[0001] This invention belongs to the field of natural fiber processing technology, specifically relating to a method for degumming ramie fibers based on a ternary homogeneous system of alkanolamine / betaine / water. Background Technology

[0002] Ramie is an important natural plant fiber raw material. Its fabrics possess excellent breathability, moisture absorption, coolness, and antibacterial and antistatic properties, making it widely used in clothing, home textiles, and industrial textiles. However, in addition to cellulose, raw ramie contains approximately 20%–35% gum components (including hemicellulose, pectin, lignin, etc.). These gums tightly bind the individual fibers, resulting in coarse, brittle fibers with poor spinnability. Therefore, degumming is a crucial step in ramie fiber processing, directly affecting fiber quality and application value. Similarly, other bast fibers such as kenaf, flax, hemp, and jute also require degumming due to gum coating, and some bast fibers (such as kenaf) have higher lignin content, making degumming even more difficult.

[0003] Currently, the chemical alkaline boiling method is the main industrial method for degumming ramie. A typical process includes: pre-soaking raw ramie in a sulfuric acid solution, washing, boiling with sodium hydroxide, followed by a second boiling (using a mixed solution of sodium hydroxide, sodium silicate, urea, hydrogen peroxide, sodium tripolyphosphate, and sodium sulfite), then multiple washings, dehydration, oiling, and drying to finally obtain refined ramie. While this method is mature and widely used, it has significant drawbacks: firstly, it uses large quantities of highly corrosive chemical reagents, generating wastewater and exhaust gases, causing serious environmental pollution, and the process is complex; secondly, the high concentration of alkaline solution inevitably damages the cellulose, leading to a decrease in ramie fiber strength and affecting its application in high-end textiles. For other bast fibers such as kenaf, the chemical alkaline boiling method also suffers from the aforementioned pollution and fiber damage problems.

[0004] To find a better degumming solution, patent CN114000205A discloses a "high-quality, low-pollution selective oxidation degumming method for ramie," which introduces a selective oxidation system. This reduces degumming time and lowers the COD value of wastewater to some extent. However, the oxidative degumming solution used in this method contains a wide variety of chemical reagents, making the system complex and resulting in significant costs and environmental pressures. Researchers both domestically and internationally have attempted degumming methods such as biological degumming or single organic amine systems. Biological degumming offers mild conditions and minimal fiber damage, but it is time-consuming (usually requiring more than 12 hours), costly, and unstable, with limited lignin removal capabilities, making industrial application difficult. Single organic amine systems (such as ethanolamine) offer mild degumming, but their efficiency is also unsatisfactory. For example, the ethanolamine degumming method mentioned in Chinese patent application CN116575131A requires prolonged heat treatment to achieve a certain degumming effect and still struggles to efficiently remove the gum. It is worth noting that most of the above alternative methods are for ramie or flax, and green degumming technologies for high-lignin hemp varieties such as kenaf and hemp are particularly lacking.

[0005] In summary, current technologies lack a degumming process that can efficiently remove various gums, including lignin, while avoiding fiber damage from strong alkalis, and is also environmentally friendly, efficient, low-cost, and applicable to various types of bast fibers. Therefore, developing an environmentally friendly, efficient degumming process that minimizes fiber damage and is applicable to ramie and other bast fibers has become a critical issue urgently needing to be addressed in the current bast fiber processing field. Summary of the Invention

[0006] The technical problem to be solved by this invention is to provide a method for degumming ramie fibers based on a ternary homogeneous system of alkanolamine / betaine / water. This method has significant advantages such as high efficiency, environmental friendliness, minimal fiber damage, and simple operation, and can provide a new and high-quality technical solution for the processing of ramie fibers.

[0007] The technical solution adopted is as follows: A method for degumming ramie fibers based on a ternary homogeneous system of alkanolamine / betaine / water includes the following steps: S1. Pretreatment of raw anesthesia: Place the ramie bast fibers in a degumming tank, slowly pour in deionized water or softened water to ensure that the liquid completely submerges the ramie bast fibers, and then seal the degumming tank. Subsequently, the sealed degumming tank is heated to the specified temperature and maintained thereafter. After pretreatment, drain the liquid from the tank, squeeze the ramie bast to dehydrate it, and set it aside for later use; S2. Degumming treatment of ternary homogeneous systems: A pre-mixed ternary homogeneous degumming solution consisting of alcoholamine, betaine, and water is pumped into the degumming tank to cover the pre-treated ramie bast. After sealing the degumming tank, heat and cook the sealed degumming tank to remove the glue. After degumming is complete, pour out all the degumming liquid from the degumming tank and collect it for recycling. Then, washing water is poured into the tank to wash the degummed ramie fibers, and after squeezing and dehydrating, ramie degummed semi-finished product is obtained; S3. Post-processing: The ramie degummed semi-finished product is subjected to dehydration, oiling, and drying processes in sequence to finally obtain the finished ramie refined dried ramie product that meets the requirements.

[0008] Preferably, in step S1, the degumming tank is heated to 80-100°C and maintained for 20-30 minutes.

[0009] Preferably, in step S2, the ternary homogeneous degumming solution includes an alcohol amine compound, a betaine compound, and water, wherein the alcohol amine is selected from at least one of monoethanolamine, diethanolamine, triethanolamine, isopropanolamine, or diethanol monoisopropanolamine, and the betaine is selected from any one of anhydrous betaine, alkylamidopropyl betaine, or sulfobetaine.

[0010] Preferably, the molar ratio of alkanolamine, betaine, and water is 1:4 to 12:2 to 5; Before use, mix the alcohol amine, betaine and water by molar ratio, and heat and stir evenly to form a ternary homogeneous degumming solution; wherein the heating temperature is 60-80℃.

[0011] Preferably, in step S2, the mass ratio of ramie bast to the ternary homogeneous degumming liquid is 1:15-30, ensuring that the liquid surface completely covers the pretreated ramie bast.

[0012] Preferably, in step S2, the degumming temperature is 130-150°C, and the constant temperature cooking time is 2-3 hours.

[0013] Preferably, the method for recovering degumming liquid is as follows: the collected degumming liquid is subjected to solid-liquid separation through a 100-300 mesh filter or a plate and frame filter press to remove the gum residue, fiber debris and insoluble impurities generated during the degumming process, and the filtrate is collected as recovered degumming liquid and stored in a sealed storage tank for later use.

[0014] Preferably, in step S2, the washing water used for cleaning is tap water; the number of cleaning cycles is 2 to 5, and the washing time for each cycle is 10 to 20 minutes, until the pH value of the washing solution is neutral.

[0015] Preferably, in step S3, the dehydration and oiling times are both 10 to 20 minutes.

[0016] Preferably, in step S3, the drying temperature is 90-110℃ and the drying time is 50-60 min.

[0017] Preferably, the method can also degumme one or more of kenaf fiber, flax fiber, hemp fiber or jute fiber.

[0018] Compared with existing technologies, the ramie fiber degumming method based on a ternary homogeneous system of alkanolamine / betaine / water provided by this invention can reduce the residual glue rate of ramie fibers to as low as 3% to 6% and the breaking strength to 7 to 8 cN / dtex. The degumming is uniform and the fiber damage is minimal. At the same time, the process does not use sulfuric acid, strong alkali, or oxidants, and the degumming wastewater can be recycled, making it green and environmentally friendly. In addition, this method eliminates the need for secondary alkaline boiling and other processes, is simple to operate, and takes only 4 to 5 hours in total. It comprehensively solves the pain points of existing technologies, such as heavy environmental pollution and significant fiber damage, and has outstanding prospects for industrial application.

[0019] To better understand the technical features of this invention, a detailed analysis and explanation are provided below: In the above technical solution, the ramie bast is first pretreated with hot water, a step that is fundamental for subsequent efficient degumming and protection of fiber quality. Specifically, the raw material is immersed in deionized or softened water at 80–100°C. The wetting, swelling, and physical washing effects of the hot water achieve a triple effect: first, it removes surface impurities such as mud and sand, preventing obstruction of contact between the degumming solution and the pectin; second, it dissolves some water-soluble pectin, reducing the subsequent degumming load; and third, it disrupts the hydrogen bond network between the amorphous regions of cellulose and the pectin, activating the fiber structure and creating channels for the degumming solution to penetrate. This pretreatment does not introduce chemical reagents and does not damage the fiber's mechanical properties, which is one of the advantages of this invention.

[0020] In the formal degumming stage, this invention innovatively uses a ternary homogeneous degumming solution composed of alcoholamine, betaine and water to synergistically treat pretreated ramie bast under closed conditions at 130-150℃. This system is the core technical feature, and the synergistic mechanism is as follows: (1) Dual function of alcoholamine: Monoethanolamine is preferred. Its amino group provides a mild alkaline environment of pH 10-12, selectively hydrolyzing the ester bonds and glycosidic bonds of pectin and hemicellulose to achieve gum degradation; the hydroxyl group and amino group combine with S-type lignin through hydrogen bonds, selectively dissolving lignin and avoiding the generation of by-products. Compared with traditional strong alkali treatment, it can significantly reduce cellulose damage and ensure fiber strength. (2) Synergistic effect of betaine: Anhydrous betaine and other amphoteric surfactants are selected to reduce the surface tension of the degumming solution and enhance the penetration and wetting ability; its ionic groups synergistically destroy the hydrogen bonds connecting gum and cellulose with alcoholamine, promote gum detachment and dispersion, and realize the integration of "penetration-degumming-dispersion", which is different from the existing single-component degumming solution. (3) The role of water as a medium: As a green solvent, water enables the alkanolamine and betaine to form a stable homogeneous system, ensuring uniform component concentration and rapid mass transfer, avoiding uneven degumming or fiber damage, and controlling the reaction in a mild and controllable manner. The constant temperature cooking conditions of 130-150℃ for 2-3 hours, combined with the ternary homogeneous degumming liquid, can quickly penetrate the fiber and efficiently degrade the gum; at the same time, the alkanolamine inhibits the alkaline degradation of cellulose, thereby maintaining a high fiber breaking strength (7-8 cN / dtex) while achieving a low residual gum rate (3%-6%).

[0021] Hot water pretreatment and ternary homogeneous degumming form an organic whole, and their synergy is key to achieving excellent results: pretreatment removes impurities and activates fibers, creating conditions for the degumming solution to penetrate; the degumming system then efficiently removes glue based on this activation. Experiments show that the absence of pretreatment leads to increased degumming resistance and a 2% increase in residual glue rate; both steps are indispensable.

[0022] Compared with existing alkaline boiling degumming technology, this invention has significant advantages, specifically as follows: (1) Green and environmentally friendly: avoid the use of highly polluting and highly corrosive reagents; degumming waste liquid can be recycled and reused, reducing chemical consumption and wastewater discharge, and solving the pollution pain points of traditional processes.

[0023] (2) Quality improvement: Gentle degumming avoids damage to cellulose. The breaking strength of fine hemp is 7-8 cN / dtex, which is significantly better than the traditional alkali method (5-6 cN / dtex). The fiber softness is improved, the breakage rate is reduced, and the added value of the product is increased.

[0024] (3) Simplified process: Only one steaming is required, which saves 4 to 5 steps compared to the traditional alkaline boiling. The operation is simple and the total time is shortened to 4 to 5 hours, reducing time and labor costs.

[0025] Therefore, this invention achieves triple advantages in environmental protection, efficiency, and quality, solves industry pain points, and has significant creativity and industrial value. Attached Figure Description

[0026] Figure 1 This is an electron microscope image of ramie fibers produced in Example 3 of the present invention.

[0027] Figure 2 This is an electron microscope image of kenaf fiber produced in Example 4 of the present invention. Detailed Implementation

[0028] The accompanying drawings are for illustrative purposes only; the invention will now be described in detail with reference to the drawings and embodiments. It should be understood that prior art or common knowledge may be omitted.

[0029] Note: Ramie raw ramie origin: Dazhou, Sichuan, with an initial gum content of 29%. 1000 kg of ramie raw ramie was divided into five equal parts, used in Examples 1, 2, and 3 and Comparative Examples 1 and 2, respectively. Red kenaf raw ramie origin: Kashgar, Xinjiang, with an initial gum content of 28%. 200 kg of red kenaf raw ramie was used in Example 4.

[0030] Example 1 A method for degumming ramie fibers based on a ternary homogeneous system of alkanolamine / betaine / water includes the following steps performed sequentially: Step 1, Pretreatment of raw anesthesia: The ramie bast fibers are placed in a degumming tank, and deionized water is slowly poured into the tank, ensuring that the liquid completely submerges the bast fibers. The degumming tank is then sealed. The temperature inside the tank is then raised to a specified temperature using a heating system and maintained at that temperature for a certain period. After pretreatment, the liquid in the tank is drained, and the ramie bast fibers are squeezed to dehydrate them for later use.

[0031] Step 2: Degumming treatment of the ternary homogeneous system of alkanolamine / betaine / water: Pump a ternary homogeneous degumming solution consisting of alkanolamine, betaine, and water into the degumming tank, ensuring that the liquid surface completely covers the pretreated ramie bast.

[0032] After sealing the degumming tank, heat it to the specified temperature and maintain a constant temperature for a certain period of time for degumming. After degumming is complete, pour out the degumming liquid from the tank, collect it, and recycle it. Then, washing water is poured into the tank to wash the degummed ramie fibers multiple times until the pH value of the washing solution is neutral. After squeezing and dehydration, the degummed ramie semi-finished product is obtained.

[0033] Step 3, Post-processing: The degummed semi-finished product is then subjected to dehydration, oiling, and drying processes in sequence to finally obtain refined ramie flax finished product that meets the requirements for industrial applications.

[0034] In step one, the heating temperature is 80℃ and the holding time is 20 minutes.

[0035] In step two, the ternary homogeneous degumming solution is composed of diethanolamine, alkylamidopropyl betaine and water in a molar ratio of 1:4:2. The three are mixed and heated and stirred evenly to form a ternary homogeneous degumming system; wherein the heating temperature is 60℃.

[0036] The mass ratio of ramie bast to ternary homogeneous degumming solution was 1:15; the heating temperature of the degumming tank was 130℃, and the constant temperature cooking time was 2 hours.

[0037] In step two, the washing time is 10 minutes, and the washing is repeated 3 times; in step three, the dehydration time is 10 minutes, the oiling time is 10 minutes, the drying temperature is 90℃, and the drying time is 50 minutes.

[0038] Product inspection and testing results: The obtained ramie fiber had a residual gum content of 5.89% and a fiber strength of 8.71 cN / dtex.

[0039] Example 2 A method for degumming ramie fibers based on a ternary homogeneous system of alkanolamine / betaine / water includes the following steps performed sequentially: Step 1, Pretreatment of raw anesthesia: Place the ramie bast fibers in a degumming tank, slowly pour in softened water to ensure the bast fibers are completely submerged, and then seal the tank. Next, use a heating system to raise the temperature inside the tank to a specified level and maintain that temperature for a certain period. After pretreatment, drain the liquid from the tank and squeeze the ramie bast fibers to remove excess water, then set aside for later use.

[0040] Step 2: Degumming treatment of the ternary homogeneous system of alkanolamine / betaine / water: Pump a ternary homogeneous degumming solution consisting of alkanolamine, betaine, and water into the degumming tank, ensuring that the liquid surface completely covers the pretreated ramie bast.

[0041] After sealing the degumming tank, heat it to the specified temperature and maintain a constant temperature for a certain period of time for degumming. After degumming, pour out the degumming liquid from the tank for collection and recycling. Then, pour washing water into the tank to wash the degummed ramie fibers multiple times until the pH value of the washing liquid is neutral. After squeezing and dehydration, the ramie degummed semi-finished product is obtained.

[0042] Step 3, Post-processing: The degummed semi-finished product is then subjected to dehydration, oiling, and drying processes in sequence to finally obtain refined ramie flax finished product that meets the requirements for industrial applications.

[0043] The heating temperature in step one is 90℃, and the holding time is 25 minutes.

[0044] The ternary homogeneous degumming solution described in step two is composed of isopropanolamine, anhydrous betaine, and water in a molar ratio of 1:6:2. The three components are mixed and heated to form a homogeneous ternary degumming system; the heating temperature is 70℃.

[0045] The mass ratio of ramie bast to ternary homogeneous degumming solution was 1:20; the heating temperature of the degumming tank was 140℃, and the constant temperature cooking time was 2.5h.

[0046] In step two, the washing time is 15 minutes, and the washing is repeated 4 times; in step three, the dehydration time is 15 minutes, the oiling time is 15 minutes, the drying temperature is 100℃, and the drying time is 55 minutes.

[0047] Product inspection and testing results: The obtained ramie fiber had a residual gum content of 4.25% and a fiber strength of 7.43 cN / dtex.

[0048] Example 3 A method for degumming ramie fibers based on a ternary homogeneous system of alkanolamine / betaine / water differs from Example 1 in that the heating temperature in step one is 100°C and the holding time is 30 min.

[0049] The ternary homogeneous degumming solution described in step two is composed of monoethanolamine, alkylamidopropyl betaine, and water in a molar ratio of 1:8:3. The three components are mixed and heated to form a homogeneous ternary degumming system; the heating temperature is 80℃.

[0050] The mass ratio of ramie bast to ternary homogeneous degumming solution was 1:30; the heating temperature of the degumming tank was 150℃, and the constant temperature cooking time was 3 hours.

[0051] In step two, the washing time is 20 minutes, and the washing is repeated 5 times; in step three, the dehydration time is 20 minutes, the oiling time is 20 minutes, the drying temperature is 110℃, and the drying time is 60 minutes.

[0052] Product inspection and testing results: The obtained ramie fiber had a residual gum content of 3.51% and a fiber strength of 7.28 cN / dtex.

[0053] Example 4 Using the same solvent system and process parameters as in Example 3, the ramie raw fiber was replaced with kenaf raw fiber. After treatment, the residual gum content of the dried kenaf was measured to be 7.5% (kenaf has a higher lignin content, making degumming more difficult, but a residual gum content of 7.5% already meets the requirements for industrial applications such as coarse yarn and burlap sacks, and can be further reduced through parameter optimization), and the breaking strength was 3.1 cN / dtex. The results indicate that the method of this invention is also applicable to the degumming of kenaf fibers.

[0054] It is foreseeable that the degumming mechanism of the present invention does not depend on a specific type of bast fiber. The gum in bast fibers such as kenaf, ramie, flax, hemp, and jute is composed of pectin, hemicellulose, and lignin, and their chemical nature is the same, differing only in relative content. Therefore, those skilled in the art can reasonably foresee that the method of the present invention is also applicable to the degumming of other bast fibers such as flax, hemp, and kenaf.

[0055] Comparative Example 1 Producing refined ramie using traditional techniques: Raw ramie fibers were pre-soaked in 1% sulfuric acid for 1 hour, then washed with water for 20 minutes; next, they were boiled in 1% sodium hydroxide for 1 hour, followed by washing with water for 20 minutes; then boiled again in a mixed solution (containing 1% sodium hydroxide, 3% sodium silicate, 3% urea, 3% hydrogen peroxide, 3% sodium tripolyphosphate, and 2% sodium sulfite) for 1 hour; after multiple washings (20 minutes each), dehydration (20 minutes), oiling (20 minutes each), and drying for 1 hour, refined ramie fibers were obtained. Product inspection and testing results: The obtained ramie fiber had a residual gum content of 2.98% and a fiber strength of 6.25 cN / dtex.

[0056] Comparative Example 2 Producing refined ramie using monoethanolamine: Step 1, Pretreatment of raw anesthesia: Place the ramie bast fibers in a degumming tank, and slowly pour in deionized or softened water, ensuring the bast fibers are completely submerged. Seal the degumming tank. Then, use a heating system to raise the temperature inside the tank to a specified level and maintain that temperature for a certain period. After pretreatment, drain the liquid from the tank and squeeze the ramie bast fibers to remove excess water, then set aside for later use.

[0057] Step 2, monoethanolamine degumming treatment: Pump ethanolamine degumming solution into the degumming tank, ensuring the liquid completely covers the pretreated ramie bast. Seal the degumming tank and heat it to the specified temperature, maintaining this constant temperature for a certain period. After cooking, drain the degumming solution from the tank and immediately inject washing water to repeatedly wash the degummed ramie fibers until the pH of the washing solution is neutral. After squeezing out the water, obtain the ramie degummed semi-finished product.

[0058] Step 3, Post-processing: The above-mentioned degummed semi-finished products are sequentially subjected to dehydration, oiling, and drying processes to finally obtain refined ramie flax products that meet the requirements of industrial applications.

[0059] The heating temperature in step one above is 100℃, and the holding time is 30 minutes.

[0060] In step two above, the mass ratio of ramie bast to monoethanolamine degumming solution is 1:30; the heating temperature of the degumming tank is 150℃, and the constant temperature cooking time is 3 hours.

[0061] In step two above, the washing time is 20 minutes, and the washing is repeated 5 times; in step three, the dehydration time is 20 minutes, the oiling time is 20 minutes, the drying temperature is 110℃, and the drying time is 60 minutes.

[0062] Product inspection and testing results: The obtained ramie fiber had a residual gum content of 9.76% and a fiber strength of 9.21 cN / dtex.

[0063] To provide a more comprehensive comparison of the processes of Examples 1 / 2 / 3 and Comparative Example 1 / 2, the present invention will be further described in conjunction with the following figures.

[0064] Figure 1 and Figure 2 These are electron microscope images of ramie and kenaf fibers produced by the ternary homogeneous system degumming method of the present invention (Examples 3 and 4), respectively. Figure 1 and Figure 2 It can be seen that the fiber product obtained by the method of the present invention has a clean surface and little residual glue, which can meet the requirements of spinning fibers.

[0065] The methods of Examples 1-4 of the present invention are compared with those of Comparative Examples 1-2, and the results are shown in Table 1 below.

[0066] Table 1. Comparison of methods and processes between the examples and comparative examples As shown in Table 1, the ramie fiber degumming method of the present invention does not use strong acids or alkalis, the degumming waste liquid can be recycled and reused, the residual glue rate is low, and it has the advantages of being green and environmentally friendly; the resulting fibers have high breaking strength and little damage to the fibers; at the same time, the method is time-saving and simple in process, which can significantly save time and reduce costs.

[0067] Compared to Comparative Example 2, this invention exhibits a lower residual glue rate, higher solvent selectivity for dissolving the glue, and a gentler, more precise, more uniform, and more controllable glue removal process. Furthermore, the degumming solution can be directly reused through simple filtration and replenishment, avoiding energy-intensive vacuum distillation, thus comprehensively improving degumming efficiency, fiber quality, and the environmental friendliness of the process. In addition, the addition of water further reduces production costs.

[0068] Of course, the above description is not intended to limit the present invention, and the present invention is not limited to the examples given above. Any changes, modifications, additions or substitutions made by those skilled in the art within the scope of the present invention should also fall within the protection scope of the present invention.

Claims

1. A method for degumming ramie fibers based on a ternary homogeneous system of alkanolamine / betaine / water, characterized in that, Includes the following steps: S1. Pretreatment of raw anesthesia: Place the ramie bast fibers in a degumming tank, slowly pour in deionized water or softened water to ensure that the liquid completely submerges the ramie bast fibers, and then seal the degumming tank. Subsequently, the sealed degumming tank is heated to the specified temperature and maintained thereafter. After pretreatment, drain the liquid from the tank, squeeze the ramie bast to dehydrate it, and set it aside for later use; S2. Degumming treatment of ternary homogeneous systems: A pre-mixed ternary homogeneous degumming solution consisting of alcoholamine, betaine, and water is pumped into the degumming tank to cover the pre-treated ramie bast. After sealing the degumming tank, heat and cook the sealed degumming tank to remove the glue. After degumming is complete, pour out all the degumming liquid from the degumming tank and collect it for recycling. Then, washing water is poured into the tank to wash the degummed ramie fibers, and after squeezing and dehydrating, ramie degummed semi-finished product is obtained; S3. Post-processing: The ramie degummed semi-finished product is subjected to dehydration, oiling, and drying processes in sequence to finally obtain the finished ramie refined dried ramie product that meets the requirements.

2. The method for degumming ramie fibers based on a ternary homogeneous system of alkanolamine / betaine / water according to claim 1, characterized in that, In step S1, the degumming tank is heated to 80-100°C and maintained for 20-30 minutes.

3. The method for degumming ramie fibers based on a ternary homogeneous system of alkanolamine / betaine / water according to claim 1, characterized in that, In step S2, the ternary homogeneous degumming solution includes an alcohol amine compound, a betaine compound, and water. The alcohol amine is selected from at least one of monoethanolamine, diethanolamine, triethanolamine, isopropanolamine, or diethanol monoisopropanolamine, and the betaine is selected from any one of anhydrous betaine, alkylamidopropyl betaine, or sulfobetaine.

4. The method for degumming ramie fibers based on a ternary homogeneous system of alkanolamine / betaine / water according to claim 3, characterized in that, The molar ratio of alcoholamine, betaine, and water is 1:4 to 12:2 to 5; Before use, mix the alcohol amine, betaine and water by molar ratio, and heat and stir evenly to form a ternary homogeneous degumming solution; wherein the heating temperature is 60-80℃.

5. The method for degumming ramie fibers based on a ternary homogeneous system of alkanolamine / betaine / water according to claim 1, characterized in that, In step S2, the mass ratio of ramie bast to the ternary homogeneous degumming liquid is 1:15-30, ensuring that the liquid surface completely covers the pretreated ramie bast.

6. The method for degumming ramie fibers based on a ternary homogeneous system of alkanolamine / betaine / water according to claim 1, characterized in that, In step S2, the degumming temperature is 130-150℃, and the constant temperature cooking time is 2-3 hours.

7. The method for degumming ramie fibers based on a ternary homogeneous system of alkanolamine / betaine / water according to claim 1, characterized in that, In step S2, the method for recovering the degumming liquid is as follows: the collected degumming liquid is separated into solid and liquid by passing it through a 100-300 mesh filter or a plate and frame filter press to remove the gum residue, fiber debris and insoluble impurities generated during the degumming process. The filtrate is collected as the recovered degumming liquid and stored in a sealed storage tank for later use.

8. The method for degumming ramie fibers based on a ternary homogeneous system of alkanolamine / betaine / water according to claim 1, characterized in that, In step S2, the washing water used is tap water; the washing is performed 2 to 5 times, with each washing session lasting 10 to 20 minutes, until the pH value of the washing solution is neutral.

9. The method for degumming ramie fibers based on a ternary homogeneous system of alkanolamine / betaine / water according to claim 1, characterized in that, In step S3, the dehydration and oiling times are both 10–20 min; the drying temperature is 90–110℃, and the drying time is 50–60 min.

10. The method for degumming ramie fibers based on a ternary homogeneous system of alkanolamine / betaine / water according to claim 1, characterized in that, The method can also degumme one or more of kenaf fiber, flax fiber, hemp fiber or jute fiber.

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