1. A method for extracting bayberry tannin extract is characterized by comprising the following steps:

(a) taking a raw material of the waxberry tree, and pretreating to obtain waxberry tree powder;

(b) mixing the waxberry tree powder obtained in the step (a), water and an auxiliary agent containing amino to form a leaching solution, and then leaching to obtain the bayberry tannin extract.

2. The method of claim 1, wherein the pre-treatment process comprises: the raw material of the waxberry trees is naturally dried, and then is processed into small blocks, and then is crushed by a crusher, and then is dried in a dryer to constant weight.

3. The method of claim 1, wherein the amino-containing auxiliary agent comprises one or more of betaine, choline chloride, and urea in step (b).

4. The method of claim 3, wherein the amount of the auxiliary agent containing amino groups in step (b) is 0.1-25% by weight of the powder of Myrica rubra.

5. The method of claim 4, wherein when the amino group-containing adjuvant is betaine, the amount of betaine is 0.1-25% by weight of the powder of Myrica rubra;

when the amino-containing auxiliary agent is choline chloride, the dosage of the choline chloride is 0.1-12% of the weight of the waxberry tree powder;

when the adjuvant containing amino group is urea, the amount of urea is 0.1-4% of the weight of the fructus Myricae Rubrae powder.

6. The method of claim 1, wherein the liquid-to-material ratio of water to powdered waxberry extract in step (b) is 6:1 (mL/g).

7. The method of claim 1, wherein the step (b) comprises leaching the bayberry extract in a constant temperature bath.

8. The method of claim 1, wherein the temperature of the leaching is 80 ℃ and the time of the leaching is 0 to 4 hours.

9. The method of claim 1, wherein the extract is cooled to room temperature after the leaching step is completed, and then the extract is filtered through a filter cloth to obtain the bayberry extract.

10. The method of claim 1, wherein the extract is cooled to room temperature after the extraction in step (b), and centrifuged to obtain the bayberry extract.

Background

Tannin extracts (Vegetable tannin extracts) are mixtures of compounds extracted from tannin-rich Vegetable raw materials, with tannins as the main active ingredient, and are initially referred to as Vegetable tanning agents or tannins from their ability to turn hides into leathers. The tannin extract has molecular weight of 500-3000, complex structure, active chemical property and extremely high biological activity, and is widely used as a diluent and a plugging agent for petroleum drilling mud, an industrial gas wet desulfurizing agent, a boiler descaling agent and an antiscaling agent besides being used for tanning at present; ore dressing inhibitor, water purification treating agent, accumulator cathode additive, metal corrosion inhibitor and the like.

At present, there are about 600 kinds of plants which can be widely used for preparing tannin extract in the world according to statistics, and more than 300 kinds of plants which can be used for producing tannin extract in China are found, but only more than ten kinds of plants which can be utilized are found, and among the more than ten kinds of plants, larch bark, myrica esculenta bark, negundo chastetree bark, bark of marathon, bark of emblic leafflower fruit, red root bark, oak bark and the like.

The existing main auxiliary extraction methods comprise a water extraction method, a supercritical fluid extraction method, a microwave auxiliary extraction method, an ultrasonic auxiliary extraction method and the like. At present, in actual production, the most traditional pure water extraction method is adopted for preparing tannin extract. The water leaching method has low requirements on production equipment and technology, is relatively simpler in production process, has the advantages of large raw material treatment capacity, low investment cost, high production speed and the like, and is suitable for industrial production in practice.

Disclosure of Invention

The invention aims to provide a method for extracting bayberry tannin extract.

The purpose of the invention is realized by the following technical scheme:

a method for extracting bayberry tannin extract comprises the following steps:

(a) taking a raw material of the waxberry tree, and pretreating to obtain waxberry tree powder;

(b) mixing the waxberry tree powder obtained in the step (a), water and an auxiliary agent containing amino to form a leaching solution, and then leaching to obtain the bayberry tannin extract.

In the step (a), the pretreatment process specifically comprises: the raw material of the waxberry trees is naturally dried, and then is processed into small blocks, and then is crushed by a crusher, and then is dried in a dryer to constant weight.

The waxberry tree raw material comprises waxberry bark raw material and waxberry branch raw material.

In the step (b), the auxiliary agent containing amino comprises one or more of betaine, choline chloride or urea.

In the step (b), the amount of the amino-containing auxiliary agent is 0.1-25% of the weight of the waxberry tree powder.

When the adjuvant containing amino group is betaine, the content of betaine is 0.1-25% of the weight of fructus Myricae Rubrae powder.

When the adjuvant containing amino group is choline chloride, the amount of choline chloride is 0.1-12% of the weight of the Myrica rubra powder.

When the adjuvant containing amino group is urea, the amount of urea is 0.1-4% of the weight of the fructus Myricae Rubrae powder.

In the step (b), the liquid-material ratio of the water to the waxberry tree powder is 6:1 (mL/g).

In the step (b), leaching is carried out by adopting a constant-temperature water bath method.

In the step (b), the leaching temperature is 80 ℃, and the leaching time is 0-4h but not 0.

In the step (b), after the leaching is finished, after the leaching solution is cooled to room temperature, filtering by using filter cloth to obtain the bayberry tannin extract, and after the filtering, concentrating the filtrate to obtain the bayberry tannin extract.

In the step (b), after the leaching is finished, the leaching solution is cooled to room temperature, and then the bayberry tannin extract is obtained by centrifugation, and the liquid can be concentrated to obtain the bayberry tannin extract after the centrifugation.

The invention mixes the auxiliary agent containing amino with water and waxberry tree powder, which can improve the yield of the plant tanning agent, and the amino on the auxiliary agent plays the following roles: 1, hydrogen bonding. Can react with hydroxyl on cell wall and cell membrane to form hydrogen bond, and promote dissolution of polyphenol structure. 2. The amino group is electropositive. The amino group can bind to cellulose or the like having a negative charge, and change the electrical property thereof. Similar to the principle of eutectic extraction. And according to different types of the auxiliary agents, the auxiliary agents with different dosages are added, so that the maximum yield of the plant tanning agent can be obtained, the extraction efficiency of the tannin extract is improved, and natural forestry resources are more effectively utilized.

Drawings

FIG. 1 is a graph showing the relationship between the amounts of betaine used in comparative example 1 and examples 4 to 8 on the extraction yield of bayberry extract;

FIG. 2 is a graph showing the relationship between the amount of choline chloride used in comparative example 1 and the amount of choline chloride used in examples 12, 13, and 20-22, and the extraction yield of bayberry extract;

FIG. 3 is a graph showing the relationship between the urea amount used in comparative example 1 and the urea amount used in examples 15, 16 and 23, and the extraction yield of the extract of bayberry.

Detailed Description

The invention is described in detail below with reference to the figures and specific embodiments.

Comparative example 1

The preparation method of the bayberry tannin extract by adopting a water extraction method comprises the following specific steps:

1. taking waxberry barks, naturally drying, processing into small square blocks with the width of 0.5-1cm, crushing into small particles by using a crusher, and then drying in a dryer to constant weight.

2. Accurately weighing 40g of waxberry bark powder, putting the waxberry bark powder into a clean 500mL three-neck flask, adding 240mL of distilled water according to the liquid-material ratio of 6:1(mL/g), shaking and mixing uniformly to form a leaching solution, putting the leaching solution into a constant-temperature water bath kettle, setting the leaching temperature to be 80 ℃, connecting a stirrer, a thermometer and a condensation reflux device, starting condensation reflux, and timing when the solution temperature reaches 80 ℃, wherein the leaching time is 4 hours.

3. After the extraction was completed, the solution was cooled and filtered through a filter cloth, and the yield of the vegetable tanning agent (i.e., the extract of the tannin extract, the same applies hereinafter) was measured to be 11.29%, as shown in fig. 1, 2 and 3.

Comparative example 2

The preparation method of the bayberry tannin extract by adopting a water extraction method comprises the following specific steps:

1. taking waxberry branches, naturally drying, processing into small square blocks with the width of 0.5-1cm, crushing into small granules by using a crusher, and then drying in a dryer to constant weight.

2. Accurately weighing 40g of waxberry branch powder, putting the waxberry branch powder into a clean 500mL three-neck flask, adding 240mL of distilled water according to the liquid-material ratio of 6:1(mL/g), shaking and mixing uniformly to form a leaching solution, putting the leaching solution into a constant-temperature water bath kettle, setting the leaching temperature to be 80 ℃, connecting a stirrer, a thermometer and a condensation reflux device, starting condensation reflux, and timing when the solution temperature reaches 80 ℃, wherein the leaching time is 4 hours.

3. After the extraction is finished, the solution is cooled and filtered by filter cloth, and the yield of the plant tanning agent is detected to be 12.03 percent.

Embodiment 3

The preparation method of the bayberry tannin extract by adopting a water extraction method comprises the following specific steps:

1. taking waxberry barks, naturally drying, processing into small square blocks with the width of 0.5-1cm, crushing into small particles by using a crusher, and then drying in a dryer to constant weight.

2. Accurately weighing 40g of waxberry bark powder, putting the waxberry bark powder into a clean 500mL three-neck flask, adding 240mL of distilled water according to the liquid-material ratio of 6:1(mL/g), adding 0.04g of betaine (accounting for 0.1% of the weight of the waxberry bark powder), shaking and mixing uniformly to form a leaching solution, putting the leaching solution into a constant-temperature water bath kettle, setting the leaching temperature to be 80 ℃, connecting a stirrer, a thermometer and a condensation reflux device, starting condensation reflux, timing when the solution temperature reaches 80 ℃, and leaching for 4 hours.

3. After the extraction is finished, the solution is cooled and filtered by filter cloth, the yield of the detected product is 13.07 percent, and the weight of the betaine is deducted, so that the yield of the plant tanning agent is 12.97 percent.

The obtained solid matter is a solid mixture containing an auxiliary agent for auxiliary extraction and a plant tanning agent, the auxiliary agent does not influence the tanning effect of the plant tanning agent, so the auxiliary agent does not need to be separated from the solid mixture, the yield of the plant tanning agent is the product minus the amount of the auxiliary agent, polyphenol in the raw material of the waxberry trees is the plant tanning agent, and a large amount of cellulose contained in the raw material of the waxberry trees is separated in filtration and centrifugation. The test steps of the content of the vegetable tanning agent are as follows: after completion of the leaching, the clear solution without solid powder is separated. From each experimental group (namely, the embodiment 3-23, and the comparative example 1-2, which is modified by referring to the calculation formula) with different additives and different addition ratios, 25mL of leaching liquor (namely, the above clear liquid) is taken and transferred into a weighing bottle, a 80 ℃ constant temperature water bath is carried out in a water bath kettle, the leaching liquor is concentrated until the solid content is more than 60%, the leaching liquor is taken out, cooled at room temperature, placed into a blast oven for drying at the constant temperature of 80 ℃, and then weighed until the constant weight X is obtained. The yield of the vegetable tanning agent is Y, and the calculation formula is as follows:

wherein 280 is the total mass of the total solid-liquid mixture when the waxberry bark or the waxberry branch is 40g and the solid-liquid ratio is 6:1, 25 is the mass of 25mL of the transferred leaching liquor, 40 is the mass of 40g of the waxberry bark or the waxberry branch, Z is the gram number of the added auxiliary agent containing amino, and if the value is actually applied, the value in the calculation formula can be modified according to the mass of the actually added waxberry tree powder, the mass of the taken water, the mass of the transferred extracting solution and the like.

Example 4

The preparation method of the bayberry tannin extract by adopting a water extraction method comprises the following specific steps:

1. taking waxberry barks, naturally drying, processing into small square blocks with the width of 0.5-1cm, crushing into small particles by using a crusher, and then drying in a dryer to constant weight.

2. Accurately weighing 40g of waxberry bark powder, putting the waxberry bark powder into a clean 500mL three-neck flask, adding 240mL of distilled water according to the liquid-material ratio of 6:1(mL/g), adding 0.32g of betaine (accounting for 0.8% of the weight of the waxberry bark powder), shaking and mixing uniformly to form a leaching solution, putting the leaching solution into a constant-temperature water bath kettle, setting the leaching temperature to be 80 ℃, connecting a stirrer, a thermometer and a condensation reflux device, starting condensation reflux, timing when the solution temperature reaches 80 ℃, and leaching for 4 hours.

3. After the leaching was completed and the solution was cooled, it was filtered through a filter cloth, and the yield of the product was measured to be 16.58%, and the weight of betaine was subtracted to obtain a yield of 15.78% of the vegetable tanning agent, as shown in fig. 1.

Example 5

The preparation method of the bayberry tannin extract by adopting a water extraction method comprises the following specific steps:

1. taking waxberry barks, naturally drying, processing into small square blocks with the width of 0.5-1cm, crushing into small particles by using a crusher, and then drying in a dryer to constant weight.

2. Accurately weighing 40g of waxberry bark powder, putting the waxberry bark powder into a clean 500mL three-neck flask, adding 240mL of distilled water according to the liquid-material ratio of 6:1(mL/g), adding 0.8g of betaine (accounting for 2% of the weight of the waxberry bark powder), shaking and mixing uniformly to form a leaching solution, putting the leaching solution into a constant-temperature water bath kettle, setting the leaching temperature to 80 ℃, connecting a stirrer, a thermometer and a condensation reflux device, starting condensation reflux, timing when the solution temperature reaches 80 ℃, and leaching for 4 hours.

3. After the leaching is completed, and the solution is cooled, the solution is filtered by using filter cloth, the yield of the product is detected to be 18.58%, and the weight of the betaine is deducted, so that the yield of the plant tanning agent is 16.85%, as shown in figure 1.

Example 6

The preparation method of the bayberry tannin extract by adopting a water extraction method comprises the following specific steps:

1. taking waxberry barks, naturally drying, processing into small square blocks with the width of 0.5-1cm, crushing into small particles by using a crusher, and then drying in a dryer to constant weight.

2. Accurately weighing 40g of waxberry bark powder, putting the waxberry bark powder into a clean 500mL three-neck flask, adding 240mL of distilled water according to the liquid-material ratio of 6:1(mL/g), adding 1.6g of betaine (accounting for 4% of the weight of the waxberry bark powder), shaking and mixing uniformly to form a leaching solution, putting the leaching solution into a constant-temperature water bath kettle, setting the leaching temperature to 80 ℃, connecting a stirrer, a thermometer and a condensation reflux device, starting condensation reflux, timing when the solution temperature reaches 80 ℃, and leaching for 4 hours.

3. After the leaching was completed and the solution was cooled, it was filtered through a filter cloth and the yield of the product was found to be 26.65%, the weight of betaine was subtracted to obtain a vegetable tanning agent yield of 22.65%, as shown in fig. 1.

Example 7

The preparation method of the bayberry tannin extract by adopting a water extraction method comprises the following specific steps:

1. taking waxberry barks, naturally drying, processing into small square blocks with the width of 0.5-1cm, crushing into small particles by using a crusher, and then drying in a dryer to constant weight.

2. Accurately weighing 40g of waxberry bark powder, putting the waxberry bark powder into a clean 500mL three-neck flask, adding 240mL of distilled water according to the liquid-material ratio of 6:1(mL/g), adding 3.2g of betaine (accounting for 8% of the weight of the waxberry bark powder), shaking and mixing uniformly to form a leaching solution, putting the leaching solution into a constant-temperature water bath kettle, setting the leaching temperature to 80 ℃, connecting a stirrer, a thermometer and a condensation reflux device, starting condensation reflux, timing when the solution temperature reaches 80 ℃, and leaching for 4 hours.

3. After the extraction was completed and the solution was cooled, the product yield was measured to be 27.85% by filtration with filter cloth, and the weight of betaine was subtracted to obtain 19.85% yield of vegetable tanning agent as shown in fig. 1.

Example 8

The preparation method of the bayberry tannin extract by adopting a water extraction method comprises the following specific steps:

1. taking waxberry barks, naturally drying, processing into small square blocks with the width of 0.5-1cm, crushing into small particles by using a crusher, and then drying in a dryer to constant weight.

2. Accurately weighing 40g of waxberry bark powder, putting the waxberry bark powder into a clean 500mL three-neck flask, adding 240mL of distilled water according to the liquid-material ratio of 6:1(mL/g), adding 4.8g of betaine (accounting for 12% of the weight of the waxberry bark powder), shaking and mixing uniformly to form a leaching solution, putting the leaching solution into a constant-temperature water bath kettle, setting the leaching temperature to 80 ℃, connecting a stirrer, a thermometer and a condensation reflux device, starting condensation reflux, timing when the solution temperature reaches 80 ℃, and leaching for 4 hours.

3. After the completion of the leaching, after the solution was cooled, it was filtered through a filter cloth, and the yield of the product was found to be 31.45%, and the weight of betaine was subtracted, yielding a vegetable tanning agent of 19.45%, as shown in fig. 1.

Example 9

The preparation method of the bayberry tannin extract by adopting a water extraction method comprises the following specific steps:

1. taking waxberry barks, naturally drying, processing into small square blocks with the width of 0.5-1cm, crushing into small particles by using a crusher, and then drying in a dryer to constant weight.

2. Accurately weighing 40g of waxberry bark powder, putting the waxberry bark powder into a clean 500mL three-neck flask, adding 240mL of distilled water according to the liquid-material ratio of 6:1(mL/g), adding 10g of betaine (accounting for 25% of the weight of the waxberry bark powder), shaking and mixing uniformly to form a leaching solution, putting the leaching solution into a constant-temperature water bath kettle, setting the leaching temperature to 80 ℃, connecting a stirrer, a thermometer and a condensation reflux device, starting condensation reflux, timing when the temperature of the solution reaches 80 ℃, and leaching for 4 hours.

3. After the extraction is finished, the solution is cooled and filtered by a filter cloth, the yield of the product is detected to be 43.32 percent, and the weight of the betaine is deducted, so that the yield of the plant tanning agent is 18.32 percent.

Embodiment 10

The preparation method of the bayberry tannin extract by adopting a water extraction method comprises the following specific steps:

1. taking waxberry barks, naturally drying, processing into small square blocks with the width of 0.5-1cm, crushing into small particles by using a crusher, and then drying in a dryer to constant weight.

2. Accurately weighing 40g of waxberry bark powder, putting the waxberry bark powder into a clean 500mL three-neck flask, adding 240mL of distilled water according to the liquid-material ratio of 6:1(mL/g), adding 4.8g of betaine (accounting for 12% of the weight of the waxberry bark powder), shaking and mixing uniformly to form a leaching solution, putting the leaching solution into a constant-temperature water bath kettle, setting the leaching temperature to 80 ℃, connecting a stirrer, a thermometer and a condensation reflux device, starting condensation reflux, timing when the solution temperature reaches 80 ℃, and leaching for 4 hours.

3. After the extraction is completed and the solution is cooled, the product yield is detected to be 33.59% by centrifugation, and the weight of the betaine is deducted, so that the yield of the plant tanning agent is 21.59%.

Example 11

The preparation method of the bayberry tannin extract by adopting a water extraction method comprises the following specific steps:

1. taking waxberry barks, naturally drying, processing into small square blocks with the width of 0.5-1cm, crushing into small particles by using a crusher, and then drying in a dryer to constant weight.

2. Accurately weighing 40g of waxberry bark powder, putting the waxberry bark powder into a clean 500mL three-neck flask, adding 240mL of distilled water according to the liquid-material ratio of 6:1(mL/g), adding 0.04g of choline chloride (accounting for 0.1% of the weight of the waxberry bark powder), shaking and mixing uniformly to form a leaching solution, putting the leaching solution into a constant-temperature water bath kettle, setting the leaching temperature to be 80 ℃, connecting a stirrer, a thermometer and a condensation reflux device, starting condensation reflux, timing when the solution temperature reaches 80 ℃, and leaching for 4 hours.

3. After the extraction is finished, after the solution is cooled, the solution is filtered by using filter cloth, the yield of the detected product is 13.69 percent, and the weight of choline chloride is deducted, so that the yield of the plant tanning agent is 13.59 percent.

Example 12

The preparation method of the bayberry tannin extract by adopting a water extraction method comprises the following specific steps:

1. taking waxberry barks, naturally drying, processing into small square blocks with the width of 0.5-1cm, crushing into small particles by using a crusher, and then drying in a dryer to constant weight.

2. Accurately weighing 40g of waxberry bark powder, putting the waxberry bark powder into a clean 500mL three-neck flask, adding 240mL of distilled water according to the liquid-material ratio of 6:1(mL/g), adding 1.6g of choline chloride (accounting for 4% of the weight of the waxberry bark powder), shaking and mixing uniformly to form a leaching solution, putting the leaching solution into a constant-temperature water bath kettle, setting the leaching temperature to 80 ℃, connecting a stirrer, a thermometer and a condensation reflux device, starting condensation reflux, timing when the solution temperature reaches 80 ℃, and leaching for 4 hours.

3. After the leaching was completed and the solution was cooled, it was filtered through a filter cloth, and the yield of the product was found to be 24.51%, and the weight of choline chloride was subtracted to obtain a yield of 20.51% of the vegetable tanning agent, as shown in fig. 2.

Example 13

The preparation method of the bayberry tannin extract by adopting a water extraction method comprises the following specific steps:

1. taking waxberry barks, naturally drying, processing into small square blocks with the width of 0.5-1cm, crushing into small particles by using a crusher, and then drying in a dryer to constant weight.

2. Accurately weighing 40g of waxberry bark powder, putting the waxberry bark powder into a clean 500mL three-neck flask, adding 240mL of distilled water according to the liquid-material ratio of 6:1(mL/g), adding 4.8g of choline chloride (accounting for 12% of the weight of the waxberry bark powder), shaking and mixing uniformly to form a leaching solution, putting the leaching solution into a constant-temperature water bath kettle, setting the leaching temperature to be 80 ℃, connecting a stirrer, a thermometer and a condensation reflux device, starting condensation reflux, timing when the solution temperature reaches 80 ℃, and leaching for 4 hours.

3. After the leaching is completed, and the solution is cooled, the solution is filtered by using filter cloth, the yield of the product is detected to be 30.97%, and the weight of choline chloride is deducted, so that the yield of the plant tanning agent is 18.97%, as shown in figure 2.

Embodiment 14

The preparation method of the bayberry tannin extract by adopting a water extraction method comprises the following specific steps:

1. taking waxberry barks, naturally drying, processing into small square blocks with the width of 0.5-1cm, crushing into small particles by using a crusher, and then drying in a dryer to constant weight.

2. Accurately weighing 40g of waxberry bark powder, putting the waxberry bark powder into a clean 500mL three-neck flask, adding 240mL of distilled water according to the liquid-material ratio of 6:1(mL/g), adding 0.04g of urea (accounting for 0.1% of the weight of the waxberry bark powder), shaking and mixing uniformly to form a leaching solution, putting the leaching solution into a constant-temperature water bath kettle, setting the leaching temperature to be 80 ℃, connecting a stirrer, a thermometer and a condensation reflux device, starting condensation reflux, timing when the solution temperature reaches 80 ℃, and leaching for 4 hours.

3. After the extraction is finished, after the solution is cooled, the solution is filtered by using filter cloth, the yield of the product is detected to be 13.15%, and the weight of the urea is deducted, so that the yield of the plant tanning agent is 13.05%.

Example 15

The preparation method of the bayberry tannin extract by adopting a water extraction method comprises the following specific steps:

1. taking waxberry barks, naturally drying, processing into small square blocks with the width of 0.5-1cm, crushing into small particles by using a crusher, and then drying in a dryer to constant weight.

2. Accurately weighing 40g of waxberry bark powder, putting the waxberry bark powder into a clean 500mL three-neck flask, adding 240mL of distilled water according to the liquid-material ratio of 6:1(mL/g), adding 0.32g of urea (accounting for 0.8% of the weight of the waxberry bark powder), shaking and mixing uniformly to form a leaching solution, putting the leaching solution into a constant-temperature water bath kettle, setting the leaching temperature to be 80 ℃, connecting a stirrer, a thermometer and a condensation reflux device, starting condensation reflux, timing when the solution temperature reaches 80 ℃, and leaching for 4 hours.

3. After the extraction was completed and the solution was cooled, the product yield was measured as 16.15% by filtration with filter cloth and the weight of urea was subtracted to obtain 15.35% yield of vegetable tanning agent as shown in fig. 3.

Example 16

The preparation method of the bayberry tannin extract by adopting a water extraction method comprises the following specific steps:

1. taking waxberry barks, naturally drying, processing into small square blocks with the width of 0.5-1cm, crushing into small particles by using a crusher, and then drying in a dryer to constant weight.

2. Accurately weighing 40g of waxberry bark powder, putting the waxberry bark powder into a clean 500mL three-neck flask, adding 240mL of distilled water according to the liquid-material ratio of 6:1(mL/g), adding 1.6g of urea (accounting for 4% of the weight of the waxberry bark powder), shaking and mixing uniformly to form a leaching solution, putting the leaching solution into a constant-temperature water bath kettle, setting the leaching temperature to 80 ℃, connecting a stirrer, a thermometer and a condensation reflux device, starting condensation reflux, timing when the solution temperature reaches 80 ℃, and leaching for 4 hours.

3. After the extraction was completed and the solution was cooled, the product yield was 21.06% by filtration with filter cloth, and the plant tanning agent yield was 17.06% by subtracting the weight of urea as shown in fig. 3.

Example 17

The preparation method of the bayberry tannin extract by adopting a water extraction method comprises the following specific steps:

1. taking waxberry branches, naturally drying, processing into small square blocks with the width of 0.5-1cm, crushing into small granules by using a crusher, and then drying in a dryer to constant weight.

2. Accurately weighing 40g of waxberry branch powder, putting the waxberry branch powder into a clean 500mL three-neck flask, adding 240mL of distilled water according to the liquid-material ratio of 6:1(mL/g), adding 1.6g of betaine (accounting for 4% of the weight of the waxberry bark powder), shaking and mixing uniformly to form a leaching solution, putting the leaching solution into a constant-temperature water bath kettle, setting the leaching temperature to 80 ℃, connecting a stirrer, a thermometer and a condensation reflux device, starting condensation reflux, timing when the solution temperature reaches 80 ℃, and leaching for 4 hours.

3. After the extraction is finished, after the solution is cooled, the solution is filtered by using filter cloth, the yield of the detected product is 27.57 percent, and the weight of the betaine is deducted, so that the yield of the plant tanning agent is 23.57 percent.

Example 18

The preparation method of the bayberry tannin extract by adopting a water extraction method comprises the following specific steps:

1. taking waxberry branches, naturally drying, processing into small square blocks with the width of 0.5-1cm, crushing into small granules by using a crusher, and then drying in a dryer to constant weight.

2. Accurately weighing 40g of waxberry branch powder, putting the waxberry branch powder into a clean 500mL three-neck flask, adding 240mL of distilled water according to the liquid-material ratio of 6:1(mL/g), adding 1.6g of choline chloride (accounting for 4% of the weight of the waxberry bark powder), shaking and mixing uniformly to form a leaching solution, putting the leaching solution into a constant-temperature water bath kettle, setting the leaching temperature to 80 ℃, connecting a stirrer, a thermometer and a condensation reflux device, starting condensation reflux, timing when the solution temperature reaches 80 ℃, and leaching for 4 hours.

3. After the extraction is finished, the solution is cooled and filtered by a filter cloth, the yield of the detected product is 26.32 percent, and the weight of choline chloride is deducted to obtain the yield of the plant tanning agent of 22.32 percent.

Example 19

The preparation method of the bayberry tannin extract by adopting a water extraction method comprises the following specific steps:

1. taking waxberry branches, naturally drying, processing into small square blocks with the width of 0.5-1cm, crushing into small granules by using a crusher, and then drying in a dryer to constant weight.

2. Accurately weighing 40g of waxberry branch powder, putting the waxberry branch powder into a clean 500mL three-neck flask, adding 240mL of distilled water according to the liquid-material ratio of 6:1(mL/g), adding 1.6g of urea (accounting for 4% of the weight of the waxberry bark powder), shaking and mixing uniformly to form a leaching solution, putting the leaching solution into a constant-temperature water bath kettle, setting the leaching temperature to 80 ℃, connecting a stirrer, a thermometer and a condensation reflux device, starting condensation reflux, timing when the solution temperature reaches 80 ℃, and leaching for 4 hours.

3. After the extraction is finished, after the solution is cooled, the solution is filtered by using filter cloth, the yield of the product is detected to be 22.61%, and the weight of the urea is deducted, so that the yield of the plant tanning agent is 18.61%.

Embodiment 20

The preparation method of the bayberry tannin extract by adopting a water extraction method comprises the following specific steps:

1. taking waxberry barks, naturally drying, processing into small square blocks with the width of 0.5-1cm, crushing into small particles by using a crusher, and then drying in a dryer to constant weight.

2. Accurately weighing 40g of waxberry bark powder, putting the waxberry bark powder into a clean 500mL three-neck flask, adding 240mL of distilled water according to the liquid-material ratio of 6:1(mL/g), adding 0.32g of choline chloride (accounting for 0.8% of the weight of the waxberry bark powder), shaking and mixing uniformly to form a leaching solution, putting the leaching solution into a constant-temperature water bath kettle, setting the leaching temperature to be 80 ℃, connecting a stirrer, a thermometer and a condensation reflux device, starting condensation reflux, timing when the solution temperature reaches 80 ℃, and leaching for 4 hours.

3. After the completion of the leaching, the solution was cooled and filtered with a filter cloth to obtain a vegetable tanning agent yield of 13%, as shown in fig. 2.

Example 21

The preparation method of the bayberry tannin extract by adopting a water extraction method comprises the following specific steps:

1. taking waxberry barks, naturally drying, processing into small square blocks with the width of 0.5-1cm, crushing into small particles by using a crusher, and then drying in a dryer to constant weight.

2. Accurately weighing 40g of waxberry bark powder, putting the waxberry bark powder into a clean 500mL three-neck flask, adding 240mL of distilled water according to the liquid-material ratio of 6:1(mL/g), adding 0.8g of choline chloride (accounting for 2% of the weight of the waxberry bark powder), shaking and mixing uniformly to form a leaching solution, putting the leaching solution into a constant-temperature water bath kettle, setting the leaching temperature to be 80 ℃, connecting a stirrer, a thermometer and a condensation reflux device, starting condensation reflux, timing when the solution temperature reaches 80 ℃, and leaching for 4 hours.

3. After the completion of the leaching, the solution was cooled and filtered with a filter cloth to obtain a vegetable tanning agent yield of 12.3%, as shown in fig. 2.

Embodiment 22

The preparation method of the bayberry tannin extract by adopting a water extraction method comprises the following specific steps:

1. taking waxberry barks, naturally drying, processing into small square blocks with the width of 0.5-1cm, crushing into small particles by using a crusher, and then drying in a dryer to constant weight.

2. Accurately weighing 40g of waxberry bark powder, putting the waxberry bark powder into a clean 500mL three-neck flask, adding 240mL of distilled water according to the liquid-material ratio of 6:1(mL/g), adding 3.2g of choline chloride (accounting for 8% of the weight of the waxberry bark powder), shaking and mixing uniformly to form a leaching solution, putting the leaching solution into a constant-temperature water bath kettle, setting the leaching temperature to be 80 ℃, connecting a stirrer, a thermometer and a condensation reflux device, starting condensation reflux, timing when the solution temperature reaches 80 ℃, and leaching for 4 hours.

3. After the completion of the leaching, the solution was cooled and filtered with filter cloth to obtain a vegetable tanning agent yield of 19.1%, as shown in fig. 2.

Example 23

The preparation method of the bayberry tannin extract by adopting a water extraction method comprises the following specific steps:

1. taking waxberry barks, naturally drying, processing into small square blocks with the width of 0.5-1cm, crushing into small particles by using a crusher, and then drying in a dryer to constant weight.

2. Accurately weighing 40g of waxberry bark powder, putting the waxberry bark powder into a clean 500mL three-neck flask, adding 240mL of distilled water according to the liquid-material ratio of 6:1(mL/g), adding 0.8g of urea (accounting for 2% of the weight of the waxberry bark powder), shaking and mixing uniformly to form a leaching solution, putting the leaching solution into a constant-temperature water bath kettle, setting the leaching temperature to 80 ℃, connecting a stirrer, a thermometer and a condensation reflux device, starting condensation reflux, timing when the solution temperature reaches 80 ℃, and leaching for 4 hours.

3. After the completion of the leaching, the solution was cooled and filtered with a filter cloth to obtain a vegetable tanning agent yield of 15.5%, as shown in fig. 3.

Comparing the comparative examples 1, 2 and 3-23, it was found that the yield of the plant tanning agent can be improved by mixing the adjuvant containing amino group with water, the powder of the bark of the waxberry or the powder of the branch of the waxberry, and the maximum yield of the plant tanning agent can be obtained by adding different amounts of the adjuvant according to the kinds of the adjuvant.

The embodiments described above are described to facilitate an understanding and use of the invention by those skilled in the art. It will be readily apparent to those skilled in the art that various modifications to these embodiments may be made, and the generic principles described herein may be applied to other embodiments without the use of the inventive faculty. Therefore, the present invention is not limited to the above embodiments, and those skilled in the art should make improvements and modifications within the scope of the present invention based on the disclosure of the present invention.