CN108193289B - A kind of pair of hemp carries out the method that biological and chemical combines a degumming - Google Patents

Abstract

The invention relates to a combined biological and chemical degumming method for hemp fibers. 8-15% hemp fiber with fiber fineness of 5.00-15.00dtex, length of 8.00-16.00cm and tensile strength of 45-90cN; degumming solution containing laccase, hemicellulase and 2,2,6, The acetic acid-sodium acetate buffer solution of 6-tetramethylpiperidine nitroxide, the degumming solution can be reused 5 to 8 times. The method combines biological and chemical degumming methods for one-step degumming, saves time and cost, avoids the treatment of strong acid and alkali, is environmentally friendly, causes little damage to fibers, and the obtained hemp fibers have high strength, high fiber separation, relatively soft, and can be Spinning performance is good.

Description

A method for combined biological and chemical degumming of hemp fibers

technical field

The invention belongs to the field of hemp degumming, and relates to a method for degumming hemp fibers in one biological and chemical combination, in particular to a method that only needs one step to remove the main colloidal components of hemp by combining biological complex enzymes and chemical reagents, and the solution can be recycled Degumming method used.

Background technique

Cannabis was banned worldwide in the early 20th century because the plant contains tetrahydrocannabinol (THB), which can be used to make stimulants and drugs. Until the 1990s, with the increasing demand for "green" textiles, low-toxicity hemp (THB<0.3%) was successfully cultivated, and hemp was recognized by the world as a raw material for textile fibers, allowing cultivation and production.

Nowadays, the degumming technologies commonly used for raw hemp mainly include natural fermentation degumming, mechanical degumming, chemical degumming, combined biological and chemical degumming, and flash degumming. There has always been a technical problem in the degumming of hemp fibers. Hemp fibers are different from other hemp fibers such as ramie and flax. Compared with other hemp fiber content is much higher. In this regard, the current academic circles have proposed a plan to retain a small amount of non-cellulose components such as lignin and hemicellulose as "bonding points" between single fibers to form bundle fibers to achieve the length required for spinning.

From the composition analysis of hemp fiber, in addition to cellulose components, non-cellulose components mainly include hemicellulose, lignin and pectin. The pectin content in the phloem tissue of the hemp stem is about 7%. There are two forms of pectin in hemp fiber, namely protopectin and water-soluble pectin. Protopectin is insoluble in water and can be dissolved in solvents such as acid and alkali. Solubilized in or removed by biological enzyme treatment. For the removal of non-cellulose and lignin, most companies at home and abroad use the chemical degumming process, and the degumming effect is obvious, but there are disadvantages such as long degumming time, high cost, high consumption, heavy fiber damage and serious environmental pollution.

The biological enzyme treatment to remove the non-cellulose components in the hemp raw hemp mainly utilizes the selectivity of the action of biological bacteria or biological enzymes, so that it can only interact with a certain component in the hemp fiber to retain other effective components. The non-cellulose components in hemp fibers are intertwined, and the removal of one non-cellulose component also destroys the structure of the other non-cellulose components. In addition, the biological enzyme removal effect is mild, and the damage to the hemp fiber is small, which is conducive to obtaining high-quality hemp fiber. At present, the following two problems are encountered in the bio-enzyme degradation treatment of a certain non-cellulose component: (1) steric hindrance between molecules, the enzyme molecule cannot directly reach the characteristic site of the reaction, which reduces the degradation reaction efficiency; This is because the action of the enzyme molecule is specific, and it can only react at a specific site, rather than the chemical bond between the cellulose molecule and the cellulose molecule, and the non-cellulose molecule and the cellulose molecule form a "sticky bond". This causes steric hindrance to the action site of the enzyme, so that the enzyme cannot reach the reaction active center, thereby reducing the efficiency of the degradation reaction; (2) Due to the intermolecular binding, the volume of the substrate molecule becomes larger, resulting in the reaction The substrate cannot enter the active center of the enzyme, which reduces the solubility of the active center domain of the enzyme reaction, and the action site of the enzyme is a characteristic chemical bond. The enzyme molecule cannot act on the chemical bond site of the reaction, which reduces the concentration of the substrate in the active center domain of the enzyme reaction, inhibits the efficient expression of the enzyme, and reduces the degradation efficiency; among the non-cellulose components of hemp fiber, lignin and hemicellulose In particular, the content is relatively high, and the mutual combination of lignin, hemicellulose and cellulose leads to the obstruction of the action site of biological enzymes and the low degumming efficiency.

Laccase is a relatively economical biological enzyme for oxidative degradation of lignin, and it is also a biological enzyme with great industrialization prospects. However, since laccases with low redox potential (0.5-0.8V) can only directly oxidize and degrade phenolic lignin structural units with low redox potential, most of the non-phenolic structural units, which account for the total amount of lignin, cannot be directly oxidatively degraded. It is oxidized by laccase, so it is necessary to use some small molecular compounds as redox mediators to realize electron transfer between laccase and substrates such as non-phenolic and macromolecular lignin, and further remove lignin and other non- Cellulose composition. "Influence of TEMPO-Mediated Oxidation on Properties of Hemp Fibers" uses TEMPO-mediated oxidation of hemp fibers (sodium hypochlorite, sodium bromide as catalyst, TEMPO), and analyzes the chemical composition of oxidized hemp fibers. It is found that the lignin content is greatly reduced, and other There is also a corresponding reduction in non-cellulose components. "Introduction of aldehyde vs. carboxylic groups to cellulose nanofibers using laccase/TEMPOmediated oxidation" investigates the chemical-chemical-chemical-chemical-induced degradation of cellulose nanofibers in aqueous solution (pH 5, 30 °C) by laccase as a biocatalyst and TEMPO or TEMPO derivatives as mediators Bioenzyme modification experiments were carried out to introduce surface-active aldehyde groups. Among them, TEMPO derivatives were more effective, but no obvious decomposition effect on hemicellulose was found.

Patent CN101463503A provides a method for degumming ramie by compounding pectinase and hemicellulase and adding calcium ion-activated enzyme activity. The degumming time of the method is short and the degumming effect is thorough, but hemp is different from ramie. The content of lignin in non-cellulose components is much higher than that of ramie, which is difficult to apply to hemp degumming. Patent CN102703994A discloses a flax biological enzyme and a process combining chemical degumming and bleaching. It uses flax degumming enzyme YL-0 and a process combining chemical degumming and bleaching to degumm the flax to obtain high-quality flax fiber. There are many steps, long process flow, low efficiency and pollution to the environment.

Patent CN1546782A provides a hemp degumming method, which uses compound enzymes to modify hemp fibers after biological enzyme degumming. This method can effectively improve various physical and chemical properties of hemp fibers, but the degumming time is as long as 45 to 50 minutes. However, the fiber needs to be modified, the operation is complicated and the cost is high. Patent CN104532364A discloses a hemp fiber degumming method, which utilizes pectinase, laccase and rice enzyme to degumming hemp, which saves materials and time, has no pollution, and has low energy consumption, but this scheme is used in biological enzyme treatment. In the past, two steps of water retting treatment and mechanical treatment are required, the process is long, the operation is not easy, and the cost is high. Patent CN104099670A discloses a two-step method for degumming cannabis by combining biological enzymes and chemicals. The method has good removal effect on cannabis non-cellulose components and less discharge of pretreated wastewater, but the process adopts a two-step method. Before the one-step biological enzyme treatment, pretreatment in a water bath at 50 °C is required and the result is unstable. The second-step chemical treatment still needs to use other chemicals such as caustic soda, which pollutes the environment and the whole degumming process has many steps and complicated processes.

In the practical application of cannabis biological enzyme degumming, there are problems such as difficult detection and control of biological enzyme activity, difficulty in production and storage of biological enzymes, etc. In addition, the treatment time of compound enzymes is long, the action time of each enzyme is not uniform, and the enzyme activity is not fully exerted. The conditions for maximum benefit are difficult to unify. The above technical problems make it difficult to achieve mass production of cannabis biological enzyme degumming.

Therefore, it is of great practical significance to develop a cannabis degumming method with simple process, green environmental protection, low cost and good degumming effect.

SUMMARY OF THE INVENTION

The purpose of the present invention is to overcome the problems of complex process, serious pollution and high cost in the prior art, and to provide a cannabis degumming method with simple process, green environmental protection, low cost and good degumming effect. In the present invention, laccase/TEMPO/hemicellulase is dissolved in a certain concentration of acetic acid-sodium acetate buffer solution for cannabis degumming. The present invention determines the optimal activity condition (pH value of laccase/hemicellase) by measuring enzyme activity. and temperature), to ensure that the enzymatic activities of the two enzymes can reach the optimal value in the same solution to exert the high efficiency of the enzymes, and TEMPO is also added to promote the activity of the enzymes, thereby further shortening the degumming time, that is, 4 to 8 hours to complete the degumming. The invention can realize degumming by one-time dipping, has short process, high benefit and environmental protection, the dipping solution can be recycled for many times, and the obtained hemp fiber after degumming has stable composition and meets spinning requirements.

For achieving the above object, the technical scheme adopted in the present invention is as follows:

A biological and chemical combined primary degumming method for hemp fibers. The raw hemp hemp is immersed in a degumming solution with a temperature of 45 to 60° C. and a pH of 4.5 to 5.5. Hemp fibers with a degree of 5.00 to 15.00 dtex, a length of 8.00 to 16.00 cm, and a tensile strength of 45 to 90 cN; the reason for selecting the temperature and pH in the above range is that the activities of laccase and hemicellulase can be At the same time, when the temperature is too low, the enzyme activity is low; when the temperature is too high, the enzyme will die and lose its activity; when the pH value is too high or too low, the enzyme activity will be low or even die. The existing biochemical combined degumming is generally carried out in multiple steps, and the present invention requires only one step to achieve the technical effect that can only be achieved by multi-step treatment. The product obtained by the present invention has low residual gum rate, moderate fiber fineness and length, and good tensile strength. , has great application prospects.

The degumming solution is an acetic acid-sodium acetate buffer solution containing laccase, hemicellulase and 2,2,6,6-tetramethylpiperidine nitroxide (TEMPO). Acetic acid-sodium acetate buffer was selected as the degumming primer, on the one hand, in order to degrade α-ether bonds and phenyl glycosidic bonds in cannabis; on the other hand, acetic acid-sodium acetate buffer solution can improve the nucleophilicity and stability of N-O radicals sex.

As the preferred technical solution:

A kind of above-mentioned method for biological and chemical combined degumming of hemp fiber, its concrete steps are as follows:

(1) prepare acetic acid-sodium acetate buffer solution;

(2) adding laccase, hemicellulase and 2,2,6,6-tetramethylpiperidine nitroxide (TEMPO) to acetic acid-sodium acetate buffer solution, stirring evenly to prepare a degumming solution;

(3) immersing hemp raw hemp in a degumming solution with a temperature of 45 to 60°C and a pH of 4.5 to 5.5, and taking out the hemp I after degumming;

(4) cannabis I is subjected to enzymatic inactivation treatment to obtain cannabis II;

(5) hemp II is washed and dried to obtain hemp fibers after degumming;

(6) get the hemp raw hemp of the same quality as step (3) and immerse it in the degumming solution after processing the first batch of hemp and then carry out steps (4) and (5) operations to obtain hemp fibers after degumming;

(7) Repeat operation step (6).

The above-mentioned method for degumming hemp fibers by biological and chemical combination, the solvent of the acetic acid-sodium acetate buffer solution is water, the solutes are acetic acid and sodium acetate; the pH of the solution is 4.5～5.5, and the acetate radical The molar concentration of ions is 0.1 to 0.2 M (mol/L).

The above-mentioned method for degumming hemp fiber by biological and chemical combination, in step (2), the enzymatic activity of the laccase is 500～700U/g, and the addition amount is that in step (3) adding hemp raw hemp 5-20% of the mass of the hemicellulase; the enzymatic activity of the hemicellulase is 100,000-200,000 U/g, and the addition amount is 0.5-2% of the mass of the hemp raw hemp added in step (3); the 2, 2, 6, 6- The addition amount of tetramethylpiperidine nitrogen oxide is 0.5-2% of the quality of the raw cannabis added in step (3). The protection scope of the present invention is not limited to this, the present invention sets the amount of enzyme added according to the enzyme activity of laccase and hemicellulase, when the enzyme activity is constant, the amount of addition is too much, the degumming is excessive, and the obtained hemp fiber has a short length, The fineness is large, the strength is low, and the cost is high; the addition amount is too small, the degumming effect cannot be achieved, the residual glue rate is high, and the obtained hemp fiber has long length, small fineness and high strength. The addition amount of TEMPO is set according to the activity of laccase and hemicellulase. Too much addition will lead to excessive degumming, resulting in short length, high fineness and low strength of hemp fibers. On the other hand, it will increase the cost. Therefore, unnecessary waste is caused; too little added amount cannot achieve degumming effect, and the obtained hemp fiber has long length, small fineness and high strength.

A kind of above-mentioned method for biological and chemical combined primary degumming of hemp fiber, in step (3), the mass liquor ratio of the hemp raw hemp to the degumming solution is 1:20. The protection scope of the mass liquor ratio of the present invention is not limited to this, and the mass liquor ratio of the present invention is set according to the addition amount and enzyme activity of laccase, hemicellulase, and TEMPO in the degumming solution.

In the above-mentioned method for degumming hemp fibers in one biological and chemical combination, the degumming time is 4-8 hours. If the degumming time is too short, the degumming effect cannot be achieved, the residual glue rate is high, and the obtained hemp fiber has a long length, small fineness and high strength; High degree and low strength.

In the above-mentioned method for degumming hemp fibers in one biological and chemical combination, the enzyme inactivation treatment is high-temperature water washing, and the temperature of the high-temperature water washing is 90-100°C. If the temperature of high-temperature washing is too low, the enzyme will still maintain a certain activity and continue to react, which will prolong the degumming time; if the temperature of high-temperature washing is too high, it will cause damage to the fibers.

In the above-mentioned method for degumming the hemp fiber by biological and chemical combination, the repetition times of step (7) are 3 to 6 times. Since the survival time of the enzyme in the solution is limited, the laccase and hemicellulase can generally survive in the degumming solution for 40 to 60 hours, so the degumming solution can generally be recycled 5 to 8 times.

Reaction mechanism:

The degumming solution of the present invention includes various biological enzymes and various chemical reagent components, and the biological enzyme degumming and chemical degumming cooperate with each other.

There is an α-ether bond between lignin, hemicellulose and cellulose in hemp. This chemical bond is sensitive to acetic acid and can be degraded by acetic acid-sodium acetate buffer solution with a certain solubility, destroying the relationship between lignin, hemicellulose and cellulose. In addition, the phenyl glycosidic bonds formed between lignin and hemicellulose or cellulose are also easily hydrolyzed by acetic acid.

Laccase oxidizes TEMPO with a higher redox potential, resulting in the formation of TEMPO with N-O· free radicals. N-O· free radicals have strong nucleophilicity and sufficient stability in acetic acid-sodium acetate buffer solution, which can be related to molecular weight. Large or high redox site lignin macromolecules react and combine with ether bonds in lignin molecules in hemp, which allows lignin molecules to enter the active center region of laccase and break the ether bonds in lignin molecules, Form sodium phenolate fragments and dissolve in solution; N-O radicals can attack benzyl ether bonds and benzyl ester bonds in hemicellulose and lignin at the same time, and N-O radicals can further disproportionate lignin macromolecules. It degrades and destroys the composite macromolecular structure composed of hemicellulose and lignin, thereby destroying the macromolecular structure and degrading hemicellulose and lignin macromolecules; N-O radicals reduce the space between hemicellulase molecules and hemicellulose. The steric hindrance and the steric hindrance of laccase and lignin molecules are beneficial to the combination of the two enzymes with the substrate. On the one hand, the high expression of enzyme activity improves the reaction efficiency of the enzyme, thereby shortening the degumming time. The active center area of the enzyme, that is, the concentration of the cannabis lignin molecular substrate in the active center area is increased, so that the reacting groups are strictly "oriented" to each other in the reaction, and the reactant molecules are acted upon and rapidly form a transition state, At this time, TEMPO plays a stable role in the induction of biological enzymes and non-cellulose in cannabis in the acetic acid-sodium acetate buffer, making it easier for biological enzymes to approach non-cellulose molecules, deforming non-cellulose molecules, and sensitive bonds. (ie mainly lignin, hemicellulose, phenolic hydroxyl groups, benzene ring side chain substituents, carbonyl groups between lignin, hemicellulose, pectin and cellulose) are broken, thereby destroying the connection between macromolecular cellulose and various non-cellulose molecules , to degrade non-cellulose substances to achieve the purpose of degumming.

The chemical degumming (TEMPO) of the present invention and the biological enzyme degumming promote each other and greatly improve the degumming effect. The invention overcomes the defects of single biological enzyme degumming effect, low degumming efficiency, serious environmental pollution by chemical degumming, high energy consumption, many degumming steps, complicated operation process, long action time and high cost in the combined chemical step-by-step treatment of biological enzymes, and provides A one-bath degumming method of biological compound enzymes combined with chemical reagents is proposed, that is, the whole hemp degumming process only needs one step in the solution to achieve the purpose of degumming, and the solution can be recycled for multiple times.

Beneficial effects:

(1) a kind of method of biological and chemical combined degumming of hemp fiber of the present invention, combined with biological and chemical degumming method to carry out one-step degumming, saving time and cost, and avoiding the treatment of strong acid and alkali, not only green and environmental protection, but also The damage caused by the fiber is small, and the obtained hemp fiber has high strength, large fiber separation, relatively softness and good spinnability;

(2) a method for degumming hemp fibers by biological and chemical combination of the present invention, the lignin and hemicellulose in the hemp fibers are removed by the combination of biological enzymes and chemicals, wherein laccase and Hemicellulase removes most of the lignin and hemicellulose of hemp fibers, which is also beneficial to the removal of other non-cellulose components, and improves the cellulose content of hemp fibers after degumming. The combination of TEMPO and laccase can make hemp cellulose molecular structure. The primary hydroxyl groups are oxidized to form aldehyde groups, and the hemp fibers are chemically modified.

Detailed ways

The present invention will be further described below in conjunction with specific embodiments. It should be understood that these examples are only used to illustrate the present invention and not to limit the scope of the present invention. In addition, it should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms also fall within the scope defined by the appended claims of the present application.

Example 1

A method for biological and chemical combined degumming of hemp fiber, the specific steps are as follows:

(1) preparation pH is 5.0, and acetate ion molar concentration is 0.2M acetic acid-sodium acetate buffer solution;

(2) Add 6.0 g of laccase, 0.3 g of hemicellulase and 0.30 g of 2,2,6,6-tetramethylpiperidine nitroxide (TEMPO) to acetic acid-sodium acetate buffer solution, and stir evenly to obtain degumming Solution, the laccase and hemicellulase of this example are produced by Jiangsu Ruiyang Biotechnology Co., Ltd. According to its specification, the enzymatic activity of laccase is 500～700U/g, and the enzymatic activity of hemicellulase is 100000～200000U/g g;

(3) immersing 30g of hemp raw hemp in a degumming solution with a temperature of 55°C, taking out after 4h of degumming to obtain hemp I, wherein the mass liquor ratio of hemp raw hemp and the degumming solution is 1:20;

(4) using 90 ℃ water to wash cannabis I to obtain cannabis II;

(5) hemp II is washed and dried to obtain hemp fibers after degumming;

(6) get 30g hemp raw hemp and immerse it in the degumming solution after the first batch of hemp and carry out steps (4) and (5) operations to obtain hemp fibers after degumming;

(7) Repeat the operation step (6) 3 times.

The average value of each index of the 5 groups of hemp fibers obtained by the treatment is: the residual glue rate is 16%, the fineness is 10.92dtex, the length is 16.28cm, and the tensile strength is 45.52cN.

Comparative Example 1

A kind of hemp fiber biological enzyme degumming method, its basic steps are the same as embodiment 1, and the difference is that TEMPO is not added in the step (2) of this example, and the average value of each index of 5 groups of hemp fibers obtained by final treatment is: residual glue The ratio is 22.32%, the fineness is 21.44dtex, the length is 17.87cm, and the tensile strength is 53.81cN. Compared with Example 1, it can be found that the fiber residue rate of Example 1 is lower, the fibers are finer, the length is moderate, and the strength is more in line with the spinning requirements. It can be seen that the addition of TEMPO improves the degumming rate of hemp fibers and reduces the degumming rate of hemp fibers. Fiber fineness improves fiber strength and product performance.

Comparative Example 2

A hemp fiber biochemical combined degumming method, the basic steps of which are the same as those in Example 1, except that the TEMPO in step (2) of this example is replaced by 2,2-azine-bis(3-ethylbenzothiazole-6) -sulfonic acid) (ABTS), the average value of each index of the 5 groups of hemp fibers obtained by the final treatment is: the residual glue rate is 20.15%, the fineness is 17.44dtex, the length is 14.87cm, and the tensile strength is 33.81cN. Compared with Example 1, it can be found that the tensile strength of the fiber prepared in this example is low, so the strength is not high, the fiber is easily brittle and the residual glue rate is high, which does not meet the spinning requirements. It can be seen that the replacement of other chemical agents seriously damages the internal structure of the fiber, resulting in a decrease in strength, so that the obtained fiber does not meet the spinning requirements.

Comparative Example 3

A hemp fiber biochemical combined degumming method, the basic steps of which are the same as those in Example 1, except that laccase is replaced by lignin peroxidase in step (2) of this example, and each of the 5 groups of hemp fibers obtained by the final treatment is processed. The average values of the items are: the residual glue rate is 22.69%, the fineness is 25.30dtex, the length is 20.05cm, and the strength is 75.02cN. Compared with Example 1, it can be found that the residual glue rate of the fibers in this example is too high, the separation degree is small, the lignin content is high, the fibers are thick and hard, and the fibers are more itchy. Laccase, hemicellulase, TEMPO and acetic acid-sodium acetate buffer solution work together to improve product performance.

Comparative Example 4

A hemp fiber biochemical combined degumming method, the basic steps of which are the same as those in Example 1, the difference is that hemicellulase is replaced by pectinase in step (2) of this example, and each of the 5 groups of hemp fibers obtained is finally processed. The average values of the indicators are: the residual glue rate is 28.32%, the fineness is 31.45dtex, the length is 20.45cm, and the tensile strength is 92.43cN. Compared with Example 1, it can be found that although the tensile strength of the fiber in this example is high, the residual glue rate is too high, the fiber fineness is poor, the fiber separation degree is small, and the fiber is coarse and hard, which is not suitable for the processing of the subsequent spinning process. Does not meet spinning requirements. Hemicellulase, laccase, TEMPO and acetic acid-sodium acetate buffer solution work together to improve product performance.

Comparative Example 5

A hemp fiber biochemical combined degumming method, the basic steps of which are the same as those in Example 1, except that in the step (1) of this example, the acetic acid-sodium acetate buffer solution is replaced with a phthalic acid-hydrochloric acid buffer solution, and the resulting 5 The average value of each index of the hemp fiber in the group is: the residual glue rate is 34.87%, the fineness is 34.60dtex, the length is 22.94cm, and the tensile strength is 130.32cN. Compared with Example 1, it can be found that the residual glue rate of the fibers in this example is high, most of the glue still remains on the fibers, and the fibers have large impurities, which do not meet the degumming requirements. Acetate-sodium acetate buffer solution, laccase, hemicellulase and TEMPO synergistically improve product performance.

Comprehensive Example 1 and Comparative Examples 1 to 5 found that only the laccase, hemicellulase, TEMPO and acetic acid-sodium acetate buffer solution of the present invention cooperate with each other to obtain the technical effect of the present invention, and the laccase of the present invention is selected. , hemicellulase, TEMPO and acetic acid-sodium acetate buffer solution, one degumming can obtain hemp fiber products with low residual gum rate, small fineness, suitable length and suitable tensile strength.

Example 2

A method for biological and chemical combined degumming of hemp fiber, the specific steps are as follows:

(1) preparation pH is 5.0, and acetate ion molar concentration is 0.2M acetic acid-sodium acetate buffer solution;

(2) Add 3 g of laccase, 0.45 g of hemicellulase and 0.3 g of 2,2,6,6-tetramethylpiperidine nitroxide to acetic acid-sodium acetate buffer solution, and stir evenly to prepare a degumming solution. Laccase and hemicellulase are the same as in Example 1;

(3) immersing 30g of hemp raw hemp in a degumming solution with a temperature of 55°C, taking out after 6h of degumming to obtain hemp I, wherein the mass liquor ratio of hemp raw hemp and the degumming solution is 1:20;

(4) Washing cannabis I with water at 100°C to obtain cannabis II;

(5) hemp II is washed and dried to obtain hemp fibers after degumming;

(6) get 30g hemp raw hemp and immerse it in the degumming solution after the first batch of hemp and carry out steps (4) and (5) operations to obtain hemp fibers after degumming;

(7) Repeat the operation step (6) 4 times.

The average value of each index of the 6 groups of hemp fibers obtained by the treatment is: the residual glue rate is 15%, the fineness is 8.43dtex, the length is 14.56cm, and the tensile strength is 60.35cN.

Example 3

A method for biological and chemical combined degumming of hemp fiber, the specific steps are as follows:

(1) preparation pH is 5.0, and acetate ion molar concentration is 0.2M acetic acid-sodium acetate buffer solution;

(2) Add 4.5g of laccase, 0.3g of hemicellulase and 0.45g of 2,2,6,6-tetramethylpiperidine nitroxide to acetic acid-sodium acetate buffer solution, and stir evenly to prepare a degumming solution. In this example The laccase and hemicellulase are the same as in Example 1;

(3) immersing 30g of hemp raw hemp in a degumming solution with a temperature of 55°C, taking out after 8h of degumming to obtain hemp I, wherein the mass liquor ratio of hemp raw hemp and the degumming solution is 1:20;

(4) Washing cannabis I with water at 95°C to obtain cannabis II;

(5) hemp II is washed and dried to obtain hemp fibers after degumming;

(6) get 30g hemp raw hemp and immerse it in the degumming solution after the first batch of hemp and carry out steps (4) and (5) operations to obtain hemp fibers after degumming;

(7) Repeat the operation step (6) 5 times.

The average value of each index of the 7 groups of hemp fibers obtained by the treatment is: the residual glue rate is 14%, the fineness is 8.23dtex, the length is 12.67cm, and the tensile strength is 53.83cN.

Example 4

A method for biological and chemical combined degumming of hemp fiber, the specific steps are as follows:

(1) preparation pH is 5.0, and acetate ion molar concentration is 0.2M acetic acid-sodium acetate buffer solution;

(2) Add 6g of laccase, 0.15g of hemicellulase and 0.6g of 2,2,6,6-tetramethylpiperidine nitroxide to acetic acid-sodium acetate buffer solution, and stir evenly to prepare a degumming solution. Laccase and hemicellulase are the same as in Example 1;

(3) immersing 30g of hemp raw hemp in a degumming solution with a temperature of 55°C, taking out after 8h of degumming to obtain hemp I, wherein the mass liquor ratio of hemp raw hemp and the degumming solution is 1:20;

(4) using 90 ℃ water to wash cannabis I to obtain cannabis II;

(5) hemp II is washed and dried to obtain hemp fibers after degumming;

(6) get 30g hemp raw hemp and immerse it in the degumming solution after the first batch of hemp and carry out steps (4) and (5) operations to obtain hemp fibers after degumming;

(7) Repeat the operation step (6) 6 times.

The average value of each index of the 8 groups of hemp fibers obtained by the treatment is: the residual glue rate is 16%, the fineness is 9.63dtex, the length is 10.11cm, and the tensile strength is 49.45cN.

Example 5

A method for biological and chemical combined degumming of hemp fiber, the specific steps are as follows:

(1) prepare the acetic acid-sodium acetate buffer solution whose pH is 4.5 and the acetate ion molar concentration is 0.1M;

(2) Add 3 g of laccase, 0.45 g of hemicellulase and 0.6 g of 2,2,6,6-tetramethylpiperidine nitroxide to acetic acid-sodium acetate buffer solution, and stir evenly to prepare a degumming solution. Laccase and hemicellulase are the same as in Example 1;

(3) immersing 30g of hemp raw hemp in a degumming solution with a temperature of 45°C, taking out after 4h of degumming to obtain hemp I, wherein the mass liquor ratio of hemp raw hemp and the degumming solution is 1:20;

(4) using 90 ℃ water to wash cannabis I to obtain cannabis II;

(5) hemp II is washed and dried to obtain hemp fibers after degumming;

(6) get 30g hemp raw hemp and immerse it in the degumming solution after the first batch of hemp and carry out steps (4) and (5) operations to obtain hemp fibers after degumming;

(7) Repeat the operation step (6) 5 times.

The average value of each index of the 7 groups of hemp fibers obtained by the treatment is: the residual glue rate is 17%, the fineness is 13.00dtex, the length is 14.00cm, and the tensile strength is 90.00cN.

Example 6

A method for biological and chemical combined degumming of hemp fiber, the specific steps are as follows:

(1) preparation pH is 5.5, and acetate ion molar concentration is 0.15M acetic acid-sodium acetate buffer solution;

(2) Add 6 g of laccase, 0.45 g of hemicellulase and 0.3 g of 2,2,6,6-tetramethylpiperidine nitroxide to acetic acid-sodium acetate buffer solution, and stir evenly to prepare a degumming solution. Laccase and hemicellulase are the same as in Example 1;

(3) immersing 30g of hemp raw hemp in a degumming solution with a temperature of 60°C, taking out after 6h of degumming to obtain hemp I, wherein the mass liquor ratio of hemp raw hemp and the degumming solution is 1:20;

(4) using 98 ℃ water to wash cannabis I to obtain cannabis II;

(5) hemp II is washed and dried to obtain hemp fibers after degumming;

(6) get 30g hemp raw hemp and immerse it in the degumming solution after the first batch of hemp and carry out steps (4) and (5) operations to obtain hemp fibers after degumming;

(7) Repeat the operation step (6) 3 times.

The average value of each index of the 5 groups of hemp fibers obtained by the treatment is: the residual glue rate is 10%, the fineness is 15.00dtex, the length is 16.00cm, and the tensile strength is 45.00cN.

Example 7

A method for biological and chemical combined degumming of hemp fiber, the specific steps are as follows:

(1) prepare the acetic acid-sodium acetate buffer solution whose pH is 5.5 and the acetate ion molar concentration is 0.1M;

(2) Add 3 g of laccase, 0.4 g of hemicellulase and 0.3 g of 2,2,6,6-tetramethylpiperidine nitroxide to acetic acid-sodium acetate buffer solution, and stir evenly to obtain a degumming solution. Laccase and hemicellulase are the same as in Example 1;

(3) immersing 30g of hemp raw hemp in a degumming solution with a temperature of 50°C, taking out after 8h of degumming to obtain hemp I, wherein the mass liquor ratio of hemp raw hemp and the degumming solution is 1:20;

(4) Washing cannabis I with water at 100°C to obtain cannabis II;

(5) hemp II is washed and dried to obtain hemp fibers after degumming;

(6) get 30g hemp raw hemp and immerse it in the degumming solution after the first batch of hemp and carry out steps (4) and (5) operations to obtain hemp fibers after degumming;

(7) Repeat the operation step (6) 4 times.

The average value of each index of the 6 groups of hemp fibers obtained by the treatment is: the residual glue rate is 14%, the fineness is 9.63dtex, the length is 12.11cm, and the tensile strength is 59.45cN.

Claims (8)

1. a kind of pair of hemp carries out the method that biological and chemical combines a degumming, it is characterized in that: hempen original ramie is immersed Temperature is 45~60 DEG C, and taking out residual gum content after degumming in the scouring solution that pH is 4.5~5.5 is 8~15%, and fibre fineness is 5.00~15.00dtex, length are 8.00~16.00cm, and tensile strength is the hemp of 45~90cN；

The scouring solution is acetic acid-sodium acetate containing laccase, hemicellulase and 2,2,6,6- tetramethyl piperidine nitrogen oxides Buffer solution.

2. a kind of pair of hemp according to claim 1 carries out the method that biological and chemical combines a degumming, special Sign is, the specific steps of which are as follows:

(1) acetic acid-sodium acetate buffer solution is prepared；

(2) by laccase, hemicellulase and 2, acetic acid-sodium acetate buffer solution is added in 2,6,6- tetramethyl piperidine nitrogen oxides, Stir evenly obtained scouring solution；

(3) hempen original ramie is immersed temperature is 45~60 DEG C, and in the scouring solution that pH is 4.5~5.5, hemp is taken out to obtain after degumming I；

(4) enzyme inactivation is carried out to hemp I to handle to obtain hemp II；

(5) hemp II is washed and is dried to obtain hemp after degumming；

(6) take degumming in the scouring solution after immersing first hemp of processing with the hempen original ramie of step (3) phase homogenous quantities laggard Row step (4) and (5) operation obtain hemp after degumming；

(7) repetitive operation step (6).

3. a kind of pair of hemp according to claim 2 carries out the method that biological and chemical combines a degumming, special Sign is that the solvent of the acetic acid-sodium acetate buffer solution is water, and solute is acetic acid and sodium acetate；PH value of solution is 4.5~5.5, Acetate ion molar concentration is 0.1~0.2M in solution.

4. a kind of pair of hemp according to claim 3 carries out the method that biological and chemical combines a degumming, special Sign is, in step (2), the enzyme activity of the laccase is 500~700U/g, and additive amount is that hempen original ramie quality is added in step (3) 5~20%；The enzyme activity of the hemicellulose enzyme is 100000~200000U/g, and additive amount is that hempen original ramie matter is added in step (3) The 0.5~2% of amount；The additive amount of the 2,2,6,6- tetramethyl piperidine nitrogen oxides is that hempen original ramie quality is added in step (3) 0.5~2%.

5. a kind of pair of hemp according to claim 4 carries out the method that biological and chemical combines a degumming, special Sign is, in step (3), the quality bath raio of the hempen original ramie and scouring solution is 1:20.

6. a kind of pair of hemp according to claim 5 carries out the method that biological and chemical combines a degumming, special Sign is that the time of the degumming is 4~8h.

7. a kind of pair of hemp according to claim 6 carries out the method that biological and chemical combines a degumming, special Sign is that the enzyme inactivation processing is that high temperature is washed, and the temperature of the high temperature washing is 90~100 DEG C.

8. a kind of pair of hemp according to claim 7 carries out the method that biological and chemical combines a degumming, special Sign is that the number of repetition of step (7) is 3~6 times.