Method for preparing spherical solidified tannin germanium precipitation agent by utilizing agriculture and forestry solid waste

Abstract

The invention relates to a method for preparing a spherical solidified tannin germanium precipitation agent by utilizing agriculture and forestry solid wastes, and belongs to the technical field of functional materials. The agricultural and forestry solid waste is sequentially subjected to pretreatment, hemicellulose removal and lignin removal to prepare high-purity cellulose, epoxy chloropropane is utilized for bridging cellulose and hexaalkyl diamine, and a section of flexible chain is introduced into the cellulose; the preparation method comprises the following steps: adding a hydrophobic organic solvent paraffin and TA-alkylamino cellulose to form a water-in-oil (W / O) system, promoting the immobilized tannin to form easily filtered spheres, adding span80 to avoid system emulsification, and adding epoxy chloropropane, bridging TA and alkylamino cellulose to prepare the spherical immobilized tannin germanium precipitation agent. The cellulose purity can reach 95% or above, and high-quality utilization of solid waste is achieved; in the spherical solidified tannin germanium precipitation agent, the steric hindrance of tannin molecular activity is small, the activity is high, the germanium precipitation rate of solidified tannin after 10 times of circulation can still reach 96.50%, and the tannin consumption required by precipitation of kilogram of germanium is reduced to 0.105 kg / kg and is reduced by 99.65% compared with the tannin consumption of existing industrial germanium precipitation.

Description

TECHNICAL FIELD

[0001] The application relates to a method for preparing a spherical solidified tannin germanium precipitating agent from agroforestry solid waste, and belongs to the technical field of functional materials. BACKGROUND

[0002] Germanium production mainly adopts a tannin germanium precipitation process, although the tannin germanium precipitation process can effectively enrich germanium, but part of the tannin has an easy hydrolysis bond, and it is difficult to recover, 30 times of tannin by mass needs to be consumed for unit germanium, and the cost of germanium precipitation needs to account for about 40% of the cost of germanium extraction, so it is urgent to solidify the tannin.

[0003] At present, the main method for solidifying tannin is cross-linking on macromolecular substrates such as cellulose, chitosan and styrene. Patent CN201510647695.7 reports a preparation method of a solidified tannin adsorption resin, tannin-based phenolic resin is obtained through phenol-formaldehyde condensation, and carboxymethyl cellulose is cross-linked with tannin by using epoxy chloropropane as a cross-linking agent, but the whole process is in aqueous phase, the product is in the form of fiber bundle, the structure is loose, the compressive strength is low, and the tannin-based phenolic resin and the carboxymethyl cellulose are both rigid substances, and the steric hindrance of tannin is large; patent CN200910065915.X reports a preparation method of a tannin acid solidified chitosan adsorbent, chitosan particles are added in tannin acid, and epoxy chloropropane is added for cross-linking, but the solidified tannin is in the form of irregular particles, and the filter-bleeding phenomenon occurs during germanium extraction, and there is no bridge flexible chain between the tannin and the substrate. Patent CN200810103131.7 reports a preparation method of a solidified tannin macroporous adsorption resin, and adopts a Mannich reaction to fix the plant tannin on a styrene-divinylbenzene copolymer, but the whole process is in aqueous phase, the solidified tannin is in the form of irregular particles, and the filter-bleeding phenomenon occurs during germanium extraction. In addition, the preparation methods reported at present are all pure substances, and the cost is high.

[0004] In summary, when the tannin is solidified on cellulose, chitosan and styrene, the preparation particles are small, the steric hindrance of tannin is large, and the cost is high. SUMMARY

[0005] In view of the problems of existing tannin solidification in cellulose, chitosan, styrene and other organic macromolecules, such as small particle preparation, large tannin steric hindrance and high cost, the application provides a method for preparing spherical solidified tannin germanium precipitating agent from agricultural and forestry solid waste, and the agricultural and forestry solid waste is pretreated, hemicellulose is removed, and lignin is removed to prepare high-purity cellulose, epoxy chloropropane is used to bridge cellulose and hexaalkyl diamine, and a flexible chain is introduced into the cellulose, a hydrophobic organic solvent paraffin is added to form a water-in-oil (W / O) system with TA-alkylamine cellulose, so that the solidified tannin is in a spherical shape which is easy to filter, span 80 is added to avoid system emulsification, and then epoxy chloropropane is added to bridge TA and alkylamine cellulose, so that the spherical solidified tannin germanium precipitating agent is prepared. The purity of the cellulose can reach more than 95%, and the solid waste is used in a high-quality manner; the steric hindrance of the tannin molecule in the spherical solidified tannin germanium precipitating agent is small, the activity is high, and after 10 cycles of the solidified tannin, the germanium precipitation rate can still reach 96.50%, and the tannin consumption for precipitating one kilogram of germanium is reduced to 0.105 kg / kg, which is reduced by 99.65% compared with the current industrial germanium precipitation tannin consumption.

[0006] A method for preparing a spherical solidified tannin germanium precipitating agent from agricultural and forestry solid waste, and the specific steps are as follows: (1) Pretreatment of agricultural and forestry waste: the agricultural and forestry waste is washed with industrial water, crushed and sieved to obtain agricultural and forestry waste powder, and the agricultural and forestry waste powder is added to industrial water and activated by ultrasonic assistance to obtain activated solid waste powder; (2) Preparation of high-purity cellulose: the activated solid waste powder is added to lye to remove hemicellulose, and then added to a sulfite solution, and the pH is adjusted to 3-5 and sulfite leaching is carried out to remove lignin, and solid-liquid separation is carried out to obtain filter residue (crude fiber purity of 60-80%) and lignin sulfonic acid solution, and the filter residue is added to a lye-hydrogen peroxide mixed solution for bleaching, and solid-liquid separation is carried out to obtain high-purity cellulose (crude fiber purity of 82-95%) and residual liquid; (3) Cellulose modification: the cellulose is ground to obtain cellulose powder, the cellulose powder is mixed with lye and frozen, and the cellulose liquid is obtained by microwave thawing, epoxy chloropropane is added to the cellulose liquid for primary modification to obtain ECH-cellulose liquid, and hexaalkyl diamine is added to the ECH-cellulose liquid for secondary modification to obtain alkylamine cellulose solution; (4) Preparation of TA-alkylamine cellulose: tannic acid is dissolved in industrial water to obtain tannic acid solution, and the alkylamine cellulose solution is added to the tannic acid solution to react to obtain TA-alkylamine cellulose solution; (5) The preparation of spherical solidified tannin germanium precipitating agent: Span 80 is added to liquid paraffin to obtain a mixed solution of span 80-liquid paraffin, and then the TA-alkylamino cellulose solution is dispersed into the mixed solution of span 80-liquid paraffin under stirring, and then the cross-linking is carried out by adding epoxy chloropropane, and then the liquid paraffin is removed by ethanol washing to obtain the spherical solidified tannin germanium precipitating agent.

[0007] Preferably, in the cleaning process of step (1), the liquid-solid ratio mL:g of industrial water to agricultural and forestry waste is 1:1-3:1, and the particle size of the agricultural and forestry waste powder is 200-400 um; in the ultrasonic-assisted activation process, the liquid-solid ratio mL:g of industrial water to agricultural and forestry waste powder is 4:1-8:1, the ultrasonic intensity is 0.25-0.5 W / cm 2 , the activation temperature is 60-90℃, and the activation time is 30-90 min.

[0008] Preferably, in the alkali immersion of step (2), the alkali solution is NaOH or KOH solution, the mass concentration of the alkali solution is 5-20%, the liquid-solid ratio mL:g of the alkali solution to the activated solid waste powder is 5:1-8:1, the temperature of the alkali immersion is 60-90℃, and the time is 30-120 min.

[0009] Preferably, in the sulfite immersion of step (2), the sulfite is sodium sulfite or sodium bisulfite, the mass concentration of the sulfite solution is 4-15%, the liquid-solid ratio mL:g of the sulfite solution to the activated solid waste powder is 5:1-8:1, the temperature of the sulfite immersion is 80-95℃, and the time is 60-180 min.

[0010] Preferably, in the alkali-hydrogen peroxide mixed solution of step (2), the mass concentration of the alkali is 5-20%, the mass concentration of the hydrogen peroxide is 2-5%, the alkali is NaOH or KOH, the liquid-solid ratio mL:g of the alkali-hydrogen peroxide mixed solution to the filter residue is 5:1-8:1, the bleaching temperature is 70-90℃, and the time is 30-90 min.

[0011] Preferably, in the step (3), the particle size of the cellulose powder is 75-185 um, the alkali solution is NaOH or KOH solution, the mass concentration of the alkali solution is 8-25%, the liquid-solid ratio mL:g of the cellulose powder to the alkali solution is 10:1-30:1, the freezing temperature is -20-0℃, the freezing time is 1-3 h, and the microwave thawing power is 60-80 kW / m 3 .

[0012] Preferably, the volume ratio of epichlorohydrin to cellulose solution in step (3) is 1:1-4:1, the temperature of the first modification is 40-60 DEG C, and the time is 1-3h; the concentration of hexaalkyl diamine is 1-5wt.%, the volume ratio of hexaalkyl diamine to ECH-cellulose solution is 1:1-1:2, the temperature of the second modification is 55-75 DEG C, and the time is 1-3h.

[0013] Preferably, the concentration of tannin solution in step (4) is 5-20wt.%, the volume ratio of alkylamine cellulose solution to tannin solution is 1:1-5:1, the reaction temperature is 30-60 DEG C, and the time is 20-60min.

[0014] Preferably, the volume content of span80 in the span80-liquid paraffin mixed solution in step (5) is 0.5%-3%, the volume ratio of span80-liquid paraffin mixed solution to TA-alkylamine cellulose solution is 5:1-10:1; the volume ratio of epichlorohydrin to span80-liquid paraffin mixed solution is 1:15-1:30, the crosslinking temperature is 20-60 DEG C, the time is 5-20h, and the stirring rate is 500-1000r / min.

[0015] The precipitation rate of germanium by the spherical solidified tannin germanium precipitating agent of the application can reach 92.00-96.50% after 10 cycles, and the tannin consumption for precipitating 1kg of germanium is reduced to 0.105-0.24kg / kg, which is reduced by 99.20-99.65% compared with the current industrial tannin consumption for germanium precipitation.

[0016] The beneficial effects of the application are: (1) The application realizes high-quality utilization of solid waste by preparing 95% pure cellulose through pretreatment of agricultural and forestry solid waste, removal of hemicellulose and removal of lignin; (2) The application first bridges hexaalkyl diamine and cellulose with epichlorohydrin before bridging tannin with cellulose, which is equivalent to introducing a flexible chain on the cellulose, so as to reduce the steric hindrance of the subsequent bridging tannin molecules, and the activity of tannin is higher; (3) The application forms a "water-in-oil (W / O)" system by using hydrophobic organic solvent paraffin and alkylamine cellulose to promote the solidified tannin to form a spherical shape which is easy to filter, and span80 is added to avoid emulsification of the system, and the precipitation rate of germanium by the solidified tannin after 10 cycles can still reach 96.50%. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 The process flowchart of the application is shown in the figure. DETAILED DESCRIPTION

[0018] The application will be further described in detail in conjunction with specific embodiments, but the protection scope of the application is not limited to the content described.

[0019] Embodiment 1: A method for preparing spherical solidified tannin germanium precipitation agent from agroforestry solid waste (see Figure 1 ), the specific steps are as follows: (1) Agroforestry waste pretreatment: The agroforestry waste (rice husk) is washed with industrial water, crushed and sieved to obtain agroforestry waste powder; the liquid-solid ratio mL:g of industrial water to agroforestry waste is 1:1, and the particle size of the agroforestry waste powder is 200 um; The agroforestry waste powder is added to industrial water and activated by ultrasonic assistance to obtain activated solid waste powder; the liquid-solid ratio mL:g of industrial water to agroforestry waste powder is 4:1, the ultrasonic intensity is 0.25 W / cm 2 , the activation temperature is 60℃, and the activation time is 30 min; (2) Preparation of high-purity cellulose: The activated solid waste powder is added to an alkali solution (5% NaOH solution) to remove hemicellulose by alkaline leaching; the liquid-solid ratio mL:g of alkali solution to activated solid waste powder is 5:1, the temperature of alkaline leaching is 60℃, and the time is 30 min; Then it is added to a sulfite solution (4% sodium sulfite solution) to adjust the pH to 3 and perform sulfite leaching to remove lignin; the liquid-solid ratio mL:g of sulfite solution to activated solid waste powder is 5:1, the sulfite leaching temperature is 80℃, and the time is 60 min, and solid-liquid separation is performed to obtain filter residue (crude fiber purity of 60%) and lignin sulfonic acid solution; The filter residue is added to a NaOH-hydrogen peroxide mixed solution for bleaching, and solid-liquid separation is performed to obtain high-purity cellulose (crude fiber purity of 82%) and residual liquid; the mass concentration of NaOH in the NaOH-hydrogen peroxide mixed solution is 5%, the mass concentration of hydrogen peroxide is 2%, the liquid-solid ratio mL:g of NaOH-hydrogen peroxide mixed solution to filter residue is 5:1, the bleaching temperature is 70℃, and the time is 30 min; (3) Cellulose modification: The cellulose is ball milled to obtain cellulose powder (average particle size of 185 um), which is mixed with an alkali solution (8% NaOH solution) and frozen; the liquid-solid ratio mL:g of cellulose powder to alkali solution is 10:1; the freezing temperature is 0℃, and the freezing time is 1 h; microwave thawing is performed to obtain a cellulose solution; the microwave thawing power is 60 kW / m 3 ; ECH-cellulose solution is obtained by adding epichlorohydrin to the cellulose solution; the volume ratio of epichlorohydrin to cellulose solution is 1:1, the temperature of the first modification is 40℃, and the time is 1 h; ECH-cellulose liquid is secondarily modified by adding hexaalkyl diamine to obtain alkyl amine cellulose solution; the concentration of hexaalkyl diamine is 1wt.%, the volume ratio of hexaalkyl diamine to ECH-cellulose liquid is 1:1, the temperature of secondary modification is 55℃, and the time is 1h; (4) TA-alkyl amine cellulose preparation: tannic acid is dissolved in water to obtain tannic acid liquid with a concentration of 5wt.%, and the alkyl amine cellulose solution is added to the tannic acid liquid to react to obtain TA-alkyl amine cellulose solution; the volume ratio of alkyl amine cellulose solution to tannic acid liquid is 1:1, the reaction temperature is 30℃, and the time is 20min; (5) Preparation of spherical solidified tannin germanium precipitating agent: span80 is added to liquid paraffin to obtain span80-liquid paraffin mixed liquid, the volume content of span80 in span80-liquid paraffin mixed liquid is 0.5%, under stirring (speed 500r / min), TA-alkyl amine cellulose solution is introduced and dispersed into span80-liquid paraffin mixed liquid, then epoxy chloropropane is added for crosslinking, and ethanol is used for washing to remove liquid paraffin to obtain spherical solidified tannin germanium precipitating agent; the volume ratio of span80-liquid paraffin mixed liquid to TA-alkyl amine cellulose solution is 5:1; the volume ratio of epoxy chloropropane to span80-liquid paraffin mixed liquid is 1:30, the crosslinking temperature is 20℃, and the time is 5h; The precipitation rate of germanium of the spherical solidified tannin germanium precipitating agent of the embodiment can still reach 92.00% after 10 cycles, and the tannin consumption for precipitating 1kg of germanium is reduced to 0.24kg, which is reduced by 99.20% compared with the current industrial tannin consumption for precipitating germanium.

[0020] Example 2: A method for preparing a spherical solidified tannin germanium precipitating agent using agricultural and forestry solid wastes (see Figure 1 ), and the specific steps are as follows: (1) Pretreatment of agricultural and forestry wastes: the agricultural and forestry wastes (straw) are cleaned by industrial water, crushed and sieved to obtain agricultural and forestry waste powder; the liquid-solid ratio mL:g of industrial water to agricultural and forestry waste is 2:1, and the particle size of the agricultural and forestry waste powder is 300um; The agricultural and forestry waste powder is added to industrial water and ultrasonically assisted to obtain activated solid waste powder; the liquid-solid ratio mL:g of industrial water to agricultural and forestry waste powder is 6:1, the ultrasonic intensity is 0.35W / cm 2 , the activation temperature is 80℃, and the activation time is 60min; (2) Preparation of high-purity cellulose: the activated solid waste powder is added to alkali solution (10% NaOH solution) for alkaline immersion to remove hemicellulose; the liquid-solid ratio mL:g of alkali solution to activated solid waste powder is 6:1, the temperature of alkaline immersion is 80℃, and the time is 90min; Then, the activated solid waste powder was added into a sulfite solution (10% sodium sulfite or sodium bisulfite solution by mass concentration) to adjust the pH to 4 and to perform sulfite leaching to remove lignin, the liquid-solid ratio mL:g of the sulfite solution to the activated solid waste powder was 6:1, the sulfite leaching temperature was 90°C, and the time was 120 min, and solid-liquid separation was performed to obtain filter residue (the crude fiber purity was 70%) and a lignin sulfonic acid solution; The filter residue was added into a NaOH-hydrogen peroxide mixed solution to bleach, and solid-liquid separation was performed to obtain high-purity cellulose (the crude fiber purity reached 92%) and a residual solution; the mass concentration of NaOH in the NaOH-hydrogen peroxide mixed solution was 10%, the mass concentration of hydrogen peroxide was 3%, the liquid-solid ratio mL:g of the NaOH-hydrogen peroxide mixed solution to the filter residue was 6:1, the bleaching temperature was 80°C, and the time was 60 min; (3) Cellulose modification: cellulose was ball milled to obtain cellulose powder (the average particle size was 150 um), the cellulose powder was mixed with an alkali solution (15% NaOH solution by mass concentration) and frozen, the liquid-solid ratio mL:g of the cellulose powder to the alkali solution was 15:1; the freezing temperature was -10°C, and the freezing time was 2 h; cellulose solution was obtained by microwave thawing, and the microwave thawing power was 75 kW / m 3 ; Epoxy chloropropane was added into the cellulose solution to perform primary modification to obtain an ECH-cellulose solution, the volume ratio of epoxy chloropropane to the cellulose solution was 2:1, the primary modification temperature was 50°C, and the time was 2 h; Hexaalkyl diamine was added into the ECH-cellulose solution to perform secondary modification to obtain an alkyl amine group cellulose solution; the concentration of hexaalkyl diamine was 3 wt.%, the volume ratio of hexaalkyl diamine to the ECH-cellulose solution was 1:1.5, the secondary modification temperature was 65°C, and the time was 2 h; (4) TA-alkyl amine group cellulose preparation: tannic acid was dissolved in water to obtain a tannic acid solution with a concentration of 10 wt.%, and the alkyl amine group cellulose solution was added into the tannic acid solution to react to obtain a TA-alkyl amine group cellulose solution; the volume ratio of the alkyl amine group cellulose solution to the tannic acid solution was 3:1, the reaction temperature was 40°C, and the time was 40 min; (5) Preparation of spherical solidified tannin germanium precipitating agent: Span 80 was added to liquid paraffin and stirred to obtain a span 80-liquid paraffin mixture, the volume content of span 80 in the span 80-liquid paraffin mixture was 1.5%, under stirring (rate 800 r / min), TA-alkylamine cellulose solution was introduced and dispersed into the span 80-liquid paraffin mixture, then epoxy chloropropane was added for crosslinking, liquid paraffin was removed by ethanol washing to obtain a spherical solidified tannin germanium precipitating agent; the volume ratio of span 80-liquid paraffin mixture to TA-alkylamine cellulose solution was 8:1; the volume ratio of epoxy chloropropane to span 80-liquid paraffin mixture was 1:20, the crosslinking temperature was 40°C, and the time was 10 h; The precipitation rate of germanium of the spherical solidified tannin germanium precipitating agent of the embodiment can still reach 95.00% after 10 cycles, and the tannin consumption for precipitating 1 kg of germanium is reduced to 0.15 kg, which is reduced by 99.50% compared with the current industrial tannin consumption for precipitating germanium.

[0021] Example 3: A method for preparing a spherical solidified tannin germanium precipitating agent from agricultural and forestry solid waste (see Figure 1 ), the specific steps are as follows: (1) Pretreatment of agricultural and forestry waste: the agricultural and forestry waste (corn cob) was washed with industrial water, crushed and sieved to obtain agricultural and forestry waste powder; the liquid-solid ratio mL:g of industrial water to agricultural and forestry waste was 3:1, and the particle size of the agricultural and forestry waste powder was 400 um; The agricultural and forestry waste powder was added to industrial water and ultrasonic-assisted activated to obtain activated solid waste powder; the liquid-solid ratio mL:g of industrial water to agricultural and forestry waste powder was 8:1, the ultrasonic intensity was 0.5 W / cm 2 , the activation temperature was 90°C, and the activation time was 90 min; (2) Preparation of high-purity cellulose: the activated solid waste powder was added to an alkali solution (20% KOH solution) to remove hemicellulose by alkaline leaching, the liquid-solid ratio mL:g of alkali solution to activated solid waste powder was 8:1, the temperature of alkaline leaching was 90°C, and the time was 120 min; Then it was added to a sulfite solution (15% sodium bisulfite solution) to adjust the pH to 5 and perform sulfite leaching to remove lignin, the liquid-solid ratio mL:g of sodium bisulfite solution to activated solid waste powder was 8:1, the sulfite leaching temperature was 95°C, and the time was 180 min, and solid-liquid separation was performed to obtain filter residue (crude fiber purity of 80%) and lignin sulfonic acid solution; The filter residue is added into a KOH-hydrogen peroxide mixed solution for bleaching, and high-purity cellulose (crude fiber purity reaches 95%) and residual liquid are obtained through solid-liquid separation; the mass concentration of KOH in the KOH-hydrogen peroxide mixed solution is 20%, the mass concentration of hydrogen peroxide is 5%, the liquid-solid ratio mL:g of the KOH-hydrogen peroxide mixed solution to the filter residue is 8:1, the bleaching temperature is 90°C, and the bleaching time is 90 min; (3) Cellulose modification: cellulose is ball milled to obtain cellulose powder (average particle size is 75 um), the cellulose powder is mixed with alkali liquor (KOH solution with a mass concentration of 25%) and frozen, the liquid-solid ratio mL:g of the cellulose powder to the alkali liquor is 30:1; the freezing temperature is -20°C, and the freezing time is 3 h; cellulose liquid is obtained through microwave thawing, and the microwave thawing power is 80 kW / m 3 ; Epoxy chloropropane is added into the cellulose liquid for primary modification to obtain ECH-cellulose liquid, the volume ratio of epoxy chloropropane to the cellulose liquid is 4:1, the primary modification temperature is 60°C, and the primary modification time is 3 h; Hexaalkyl diamine is added into the ECH-cellulose liquid for secondary modification to obtain alkyl amine cellulose solution; the concentration of hexaalkyl diamine is 5 wt.%, the volume ratio of hexaalkyl diamine to the ECH-cellulose liquid is 1:2, the secondary modification temperature is 75°C, and the secondary modification time is 3 h; (4) TA-alkyl amine cellulose preparation: tannic acid is dissolved in water to obtain tannic acid liquid with a concentration of 20 wt.%, and the alkyl amine cellulose solution is added into the tannic acid liquid to react to obtain TA-alkyl amine cellulose solution; the volume ratio of the alkyl amine cellulose solution to the tannic acid liquid is 5:1, the reaction temperature is 60°C, and the reaction time is 60 min; (5) Preparation of spherical solidified tannin germanium precipitating agent: span 80 is added into liquid paraffin to obtain span 80-liquid paraffin mixed liquid, the volume content of span 80 in the span 80-liquid paraffin mixed liquid is 3%, under stirring (speed is 1000 r / min), the TA-alkyl amine cellulose solution is introduced and dispersed into the span 80-liquid paraffin mixed liquid, and then epoxy chloropropane is added for crosslinking, and ethanol is used for washing to remove liquid paraffin, to obtain spherical solidified tannin germanium precipitating agent; the volume ratio of the span 80-liquid paraffin mixed liquid to the TA-alkyl amine cellulose solution is 10:1; the volume ratio of epoxy chloropropane to the span 80-liquid paraffin mixed liquid is 1:15, the crosslinking temperature is 60°C, and the crosslinking time is 20 h; The precipitation rate of germanium of the spherical solidified tannin germanium precipitating agent in this embodiment can still reach 96.50% after 10 cycles, and the tannin consumption for precipitating 1 kg of germanium is reduced to 0.105 kg / kg, which is reduced by 99.65% compared with the current industrial germanium precipitation tannin consumption.

[0022] The above detailed description of the present application is made with reference to specific embodiments thereof, but the present application is not limited to the above embodiments, and various changes can be made within the knowledge of those skilled in the art without departing from the spirit of the present application.

Claims

1. A method for preparing spherical solidified tannin germanium precipitate using agricultural and forestry solid waste, characterized in that, The specific steps are as follows: (1) Pretreatment of agricultural and forestry waste: Agricultural and forestry waste is washed with industrial water, crushed and screened to obtain agricultural and forestry waste powder. The agricultural and forestry waste powder is added to industrial water and activated by ultrasonic assistance to obtain activated solid waste powder. (2) Preparation of high-purity cellulose: Activated solid waste powder is added to alkaline solution for alkaline leaching to remove hemicellulose, and then added to sulfite solution. The pH is adjusted to 3-5 and sulfite leaching is carried out to remove lignin. Solid-liquid separation yields filter residue and lignin sulfonic acid solution. The filter residue is added to alkaline solution-hydrogen peroxide mixed solution for bleaching. Solid-liquid separation yields high-purity cellulose and residual liquid. (3) Cellulose modification: Cellulose is ball-milled to obtain cellulose powder, the cellulose powder is mixed with alkaline solution and frozen, and then thawed by microwave to obtain cellulose solution. Epichlorohydrin is added to the cellulose solution for primary modification to obtain ECH-cellulose solution, and hexaalkyldiamine is added to the ECH-cellulose solution for secondary modification to obtain alkylamine cellulose solution. (4) Preparation of TA-alkylamino cellulose: Tannic acid is dissolved in industrial water to obtain tannic acid solution, and alkylamino cellulose solution is added to tannic acid solution to react and obtain TA-alkylamino cellulose solution; (5) Preparation of spherical cured tannin germanium precipitant: Span80 was added to liquid paraffin and stirred to obtain a Span80-liquid paraffin mixture. Under stirring conditions, TA-alkylamine cellulose solution was guided and dispersed into the Span80-liquid paraffin mixture. Epichlorohydrin was then added for crosslinking. The liquid paraffin was removed by washing with ethanol to obtain a spherical cured tannin germanium precipitant.

2. The method for preparing spherical solidified tannin germanium precipitate using agricultural and forestry solid waste according to claim 1, characterized in that: In step (1), the liquid-to-solid ratio (mL:g) of industrial water to agricultural and forestry waste during the cleaning process is 1:1 to 3:1, and the particle size of the agricultural and forestry waste powder is 200 to 400 μm; during the ultrasonic-assisted activation process, the liquid-to-solid ratio (mL:g) of industrial water to agricultural and forestry waste powder is 4:1 to 8:1, and the ultrasonic intensity is 0.25 to 0.5 W / cm. 2 The activation temperature is 60~90℃ and the activation time is 30~90min.

3. The method for preparing spherical solidified tannin germanium precipitate using agricultural and forestry solid waste according to claim 1, characterized in that: Step (2) Alkaline leaching to remove hemicellulose: The alkaline solution is NaOH or KOH solution with a mass concentration of 5-20%. The liquid-solid ratio of the alkaline solution to the activated solid waste powder is 5:1-8:1 (mL:g). The alkaline leaching temperature is 60-90℃ and the time is 30-120 min.

4. The method for preparing spherical solidified tannin germanium precipitate using agricultural and forestry solid waste according to claim 1, characterized in that: Step (2) The sulfite is sodium sulfite or sodium bisulfite. The mass concentration of the sulfite solution is 4~15%. The liquid-solid ratio of the sulfite solution to the activated solid waste powder is 5:1~8:1 mL:g. The sulfite leaching temperature is 80~95℃ and the time is 60~180min.

5. The method for preparing spherical solidified tannin germanium precipitate using agricultural and forestry solid waste according to claim 1, characterized in that: Step (2) The mass concentration of alkali solution in the alkali-hydrogen peroxide mixed solution is 5~20%, the mass concentration of hydrogen peroxide is 2~5%, the alkali is NaOH or KOH, the liquid-solid ratio of alkali-hydrogen peroxide mixed solution to filter residue is 5:1~8:1 mL:g, the bleaching temperature is 70~90℃, and the time is 30~90min.

6. The method for preparing spherical solidified tannin germanium precipitate using agricultural and forestry solid waste according to claim 1, characterized in that: Step (3) The particle size of the cellulose powder is 75~185um, the alkali solution is NaOH or KOH solution, the mass concentration of the alkali solution is 8~25%, and the liquid-solid ratio of cellulose powder to alkali solution is 10:1~30:1 mL:g; the freezing temperature is -20~0℃, the freezing time is 1~3h; the microwave thawing power is 60~80kW / m 3 .

7. The method for preparing spherical solidified tannin germanium precipitate using agricultural and forestry solid waste according to claim 1, characterized in that: Step (3) The volume ratio of epichlorohydrin to cellulose liquid is 1:1 to 4:1, the temperature of the first modification is 40 to 60°C, and the time is 1 to 3 hours; the concentration of hexaalkyldiamine is 1 to 5 wt.%, the volume ratio of hexaalkyldiamine to ECH-cellulose liquid is 1:1 to 1:2, the temperature of the second modification is 55 to 75°C, and the time is 1 to 3 hours.

8. The method for preparing spherical solidified tannin germanium precipitate using agricultural and forestry solid waste according to claim 1, characterized in that: Step (4) The concentration of tannic acid solution is 5~20wt.%, the volume ratio of alkylamine cellulose solution to tannic acid solution is 1:1~5:1, the reaction temperature is 30~60℃, and the time is 20~60min.

9. The method for preparing spherical solidified tannin germanium precipitate using agricultural and forestry solid waste according to claim 1, characterized in that: Step (5) The volume content of Span80 in the Span80-liquid paraffin mixture is 0.5%~3%, the volume ratio of Span80-liquid paraffin mixture to TA-alkylamino cellulose solution is 5:1~10:1; the volume ratio of epichlorohydrin to Span80-liquid paraffin mixture is 1:15~1:30, the crosslinking temperature is 20~60℃, the time is 5~20h, and the stirring rate is 500~1000r / min.

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