阅读说明：本技术 一种光酶耦合催化材料的制备方法及其应用 (Preparation method and application of photo-enzyme coupling catalytic material ) 是由 武丁胜 凤权 刘锁 曾海鳌 陶云 胡金燕 陈子秀 周堂 赵磊 于 2020-12-17 设计创作，主要内容包括：本发明提供了一种光酶耦合催化材料的制备方法及其应用,制备方法包括如下步骤：步骤一、将GO和TiO-2负载于水刺黏胶纤维膜上；步骤二、将负载GO和TiO-2的水刺黏胶纤维膜置于木醋杆菌培养液中通过原位生长的方式制备水刺黏胶纤维/GO/TiO-2/BC复合纤维膜；步骤三、对复合纤维膜进行ATRP接枝改性处理；步骤四、对接枝改性后的复合纤维膜配位过渡金属离子；步骤五、对配位过渡金属离子的水刺黏胶纤维/GO/TiO-2/BC复合纤维膜进行氧化还原酶的固定化,以得到光酶耦合催化材料。光酶耦合催化材料可以快速高效降解多种染料废水,而且具有优异的重复使用性能。(The invention provides a preparation method and application of a photo-enzyme coupling catalytic material, wherein the preparation method comprises the following steps: step one, mixingGO and TiO 2 Loading on a spunlace viscose fiber film; step two, loading GO and TiO 2 The spunlace viscose fiber membrane is placed in a wood vinegar bacillus culture solution to prepare spunlace viscose fiber/GO/TiO by an in-situ growth mode 2 a/BC composite fiber membrane; step three, performing ATRP grafting modification treatment on the composite fiber membrane; fourthly, coordinating transition metal ions to the grafted and modified composite fiber membrane; step five, carrying out spunlace viscose fiber/GO/TiO of coordination transition metal ions 2 And (3) carrying out immobilization of oxidoreductase by the aid of the/BC composite fiber membrane to obtain the photocatalytic material coupled by the aid of the light enzyme. The photo-enzyme coupling catalytic material can be used for quickly and efficiently degrading various dye wastewater and has excellent reusability.)

1. A preparation method of a photo-enzyme coupling catalytic material is characterized by comprising the following steps:

step one, mixing GO and TiO₂Loading on a spunlace viscose fiber film;

step two, loading GO and TiO₂The spunlace viscose fiber membrane is placed in a wood vinegar bacillus culture solution to prepare spunlace viscose fiber/GO/TiO by an in-situ growth mode₂a/BC composite fiber membrane;

step three, carrying out spunlace viscose fiber/GO/TiO₂Performing ATRP grafting modification treatment on the/BC composite fiber membrane;

step four, carrying out grafting modification on the spunlace viscose/GO/TiO₂the/BC composite fiber membrane coordinates transition metal ions;

step five, carrying out spunlace viscose fiber/GO/TiO of coordination transition metal ions₂And (3) carrying out immobilization of oxidoreductase by the aid of the/BC composite fiber membrane to obtain the photocatalytic material coupled by the aid of the light enzyme.

2. The method for preparing the photo-enzyme coupled catalytic material of claim 1, wherein GO and TiO are in the first step₂The method for loading the spun-laced viscose fiber membrane comprises the steps of taking GO slices and TiO₂Forming a solution of nano particles in deionized water, performing ultrasonic oscillation to form a uniform solution, and performing suction filtration on the uniform solution by using a spunlace adhesive fiber membrane to prepare the spunlace adhesive fiber membrane/GO/TiO₂Composite fiberMaintaining the membrane; wherein, GO slice and TiO₂The mass-volume ratio of the nano particles to the deionized water is (0.01-0.2) g, (0.02-0.3) g:500 mL.

3. The method for preparing the photo-enzyme coupled catalytic material of claim 2, wherein the GO slice and the TiO are₂The mass volume ratio of the nano particles to the deionized water is (0.1-0.15) g: (0.25-0.3) g:500mL, and the uniform solution was suction filtered twice continuously with a spun-laced adhesive fibrous membrane.

4. The method for preparing the photo-enzyme coupled catalytic material as claimed in claim 1, wherein the spun-laced viscose/GO/TiO fiber is prepared in the second step₂The method for preparing the/BC composite fiber membrane comprises the following steps:

a. putting the acetobacter xylinum bacterial liquid into a fiber membrane/GO/TiO containing spunlace viscose₂Standing and culturing for 3-7 days in a culture dish of the composite fiber membrane at a constant temperature of 30 ℃;

b. taking out the spun-laced viscose fiber membrane/GO/TiO from the culture solution₂The composite fiber membrane is prepared by firstly reacting 0.1-0.5 mol/L NaOH solution at 80-100 ℃ for 24-48 h to remove a culture medium, then removing redundant impurities and alkali liquor by using deionized water at 60-100 ℃, and finally freeze-drying at-60 ℃ for 24-48 h to obtain the spunlace viscose/GO/TiO₂a/BC composite material.

5. The method for preparing a photo-enzyme coupled catalytic material as claimed in claim 1, wherein the culture solution of Acetobacter xylinum contains 2.8-3.5g of tryptone, 4.9-5.5g of yeast powder and 23-25g of mannitol per L of culture solution.

6. The method for preparing the photo-enzyme coupled catalytic material according to claim 1, wherein the method for performing ATRP graft modification treatment in the third step comprises the following steps:

s1, spun-laced viscose/GO/TiO₂The initiation reaction of the/BC composite fiber membrane: firstly spunlace viscose fiber/GO/TiO₂Placing the/BC composite fiber membrane into tetrahydrofuran, stirring to remove impurities, then placing the mixture into a mixed solution of triethylamine, tetrahydrofuran and dibromo isobutyryl bromide with a volume ratio of 65-75:45-55:60-65, taking out after finishing oscillation reaction in a constant-temperature water bath kettle at 35 ℃, then cleaning with tetrahydrofuran, and storing in tetrahydrofuran;

s2, spun-laced viscose/GO/TiO₂The method comprises the following steps of (1) graft modification of a/BC composite fiber membrane:

(1) mixing N, N-dimethylacetamide and hydroxyethyltriethylenetetramine in a volume ratio of 55-60:1-2 to form a solution A;

(2) freezing hydroxyethyl methacrylate, thawing, and adding Cu₂Putting the O into hydroxyethyl methacrylate solution, and freezing and thawing the O for three times again to form solution B; the volume ratio of the hydroxyethyl methacrylate to the N, N-dimethylacetamide is 1:1, and Cu is₂The mass-volume ratio of O to hydroxyethyl methacrylate is 0.1-0.2:48-50 g/mL;

(3) respectively putting the A, B solution into a glove box in a nitrogen atmosphere, uniformly stirring the solution B after the solution B is melted, and then carrying out spunlace viscose/GO/TiO₂Placing the/BC composite fiber membrane into the mixed solution of the A and the B for reaction;

(4) the spun-laced viscose fiber/GO/TiO after reaction₂Taking out the/BC composite fiber membrane, sequentially washing with absolute ethyl alcohol and deionized water, and carrying out vacuum freeze drying to obtain the atom transfer radical modified spunlace adhesive fiber/GO/TiO₂a/BC composite fiber membrane.

7. The method for preparing a photo-enzyme coupled catalytic material according to claim 1, wherein the method for coordinating transition metal ions in the fourth step comprises the steps of preparing Fe with a concentration of 10-100 mg/L respectively³⁺、Cu²⁺Ion solution, and then at the temperature of 25 ℃, modifying ATPR by using spunlace viscose fiber/GO/TiO₂Fe is put into the/BC composite fiber membrane respectively³⁺、Cu²⁺The ionic solution is taken out after being adsorbed for 24 hours, and then the Fe with coordination is obtained after being washed and vacuum freeze-dried³⁺、Cu²⁺And (4) forming the ionized composite fiber membrane.

8. The preparation method of the photo-enzyme coupled catalytic material according to claim 1, wherein the method for immobilizing the oxidoreductase in the fifth step is to firstly dissolve the biological oxidoreductase in a buffer solution to prepare an enzyme solution with a concentration of 0.5-3g/L, then put the composite fiber membrane with coordinated transition metal ions in the enzyme solution, shake the composite fiber membrane at 4 ℃ for 8-12 hours to prepare the spunlace viscose/GO/TiO of the immobilized enzyme₂a/BC composite fiber membrane.

9. The method for preparing the photo-enzyme coupled catalytic material according to claim 8, wherein the oxidoreductase is laccase, and the buffer is acetic acid-sodium acetate buffer; or the oxidoreductase is catalase, and the buffer solution is PBS buffer solution.

10. Use of the photo-enzyme coupled catalytic material prepared by the method for preparing the photo-enzyme coupled catalytic material according to any one of claims 1 to 9 in the treatment of dye wastewater.

Technical Field

The invention relates to the technical field of photocatalytic composite materials, in particular to a preparation method and application of a photocatalytic material coupled with a light enzyme.

Background

The Bacterial Cellulose (BC) is three-dimensional aerogel nanofiber (the diameter is about 40-60nm) obtained in the process of culturing acetic acid bacteria microorganisms, and the BC nanofiber membrane has a three-dimensional flexible structure, has unique physical and chemical properties such as high crystallinity, high water binding capacity, high tensile strength and degradability and has wide application prospects in the fields of environmental protection, foods, medicines and the like. The spunlace viscose fiber is a fiber membrane with certain strength formed by reinforcing the fiber by jetting high-pressure micro water flow onto a multi-layer fiber net to entangle the fiber. Due to the characteristics of simple and efficient preparation process, no environmental pollution and the like, the product gradually enters the visual field of people and is widely applied to the fields of medical supplies, industrial supplies, clothing supplies and the like.

TiO₂As a common photocatalyst, a semiconductor is widely applied to the field of degradation of organic pollutants because of its excellent electronic structure combination, light adsorption property, carrier transport property and excited state lifetime. However, the photocatalyst has some disadvantages which limit the catalytic performance, such as difficult recovery of the catalyst from the reaction system and easy secondary pollution; second, TiO₂The band gap width of the optical waveguide is wider, about 3.2eV, so a small part of high-energy ultraviolet light in sunlight is required to be irradiated to be excited, a photogenerated electron-hole pair is generated, and the generated photogenerated electron and hole can be quickly recombined. Therefore, researchers have attempted to utilize an external oxidizing agent or the like (O)₃、O₂、Fe³⁺) Modified TiO₂A catalyst. Firstly, the modification by adding an oxidant has been proved to be beneficial to the transmission of photon-generated carriers, so as to improve the photoelectric conversion efficiency under the irradiation of visible light. Secondly, adding an external oxidant (O) into the photocatalytic reaction system₃、O₂、Fe³⁺) The oxidant in the reaction system reacts with electrons, so that the generation of hydroxyl in the system can be promoted, and the recombination of electrons and holes can be inhibited, and the two aspects are important ways for improving the rate and efficiency of the photocatalytic oxidation reaction.

The enzyme is used as an efficient biocatalyst, has the characteristics of environmental protection, high efficiency, specificity, mild catalysis condition and the like, and can be widely applied to the fields of medicine, food, papermaking, textile, environment and the like. However, enzymes also have major disadvantages in real-life use. On one hand, the biological enzyme is difficult to be stably stored for a long time in a free state, and is very easy to be influenced by special space structure or conformation of the enzyme due to environmental change (such as strong acid, strong alkali, high temperature and corresponding organic solvent) in practical application, so that the biological enzyme is denatured and inactivated; on the other hand, when the enzyme is used under the free condition, the enzyme is difficult to be thoroughly separated from the reaction system, secondary pollution of the reaction system is easy to be caused, and the enzyme cannot be repeatedly used for many times in the actual using process, so that great waste is caused. In order to solve the problems, the application field of the enzyme is further widened, and the immobilized enzyme technology is produced at the same time. The immobilized enzyme technology is characterized in that a specific carrier is adopted, and a certain immobilized enzyme method is adopted to limit the biological enzyme in a certain area for catalytic reaction.

Atom Transfer Radical Polymerization (ATRP) is a novel active polymerization reaction, high-density grafting with a molecular brush structure can be obtained on the surface of a polymer by an ATRP technology, the main chain of a high-molecular polymer is relatively straightened due to mutual repulsion between side chains of the high-density grafting, the whole polymer presents a brush-shaped conformation, and has an ultrahigh specific surface area, and the surface of the polymer has abundant functional groups due to molecular design. The ATRP technology has the advantages of free radical polymerization and active polymerization, and can graft functional molecular brushes by using a large number of hydroxyl groups on the surface of fibers as active sites. In addition, the method is wide in monomer application range, the molecular brush with controllable polymerization degree can be obtained on the surface of the material through reasonable optimization of key factors under mild conditions, and most of the current related researches report that the molecular brush is grafted on the surface of a micron-scale fiber-based material and is applied to the fixation of nucleic acid and protein. However, there has not been any breakthrough progress in the fields of ATRP modification based on bacterial cellulose nanofibers and GO (graphene) chips, application of the ATRP modification to inorganic and biocatalyst immobilization, and the like.

Disclosure of Invention

The invention aims to solve the technical problems in the prior art. Therefore, the invention provides a preparation method and application of a photo-enzyme coupling catalytic material, and aims to construct a photo-enzyme coupling catalytic material for efficiently degrading dye wastewater.

Based on the above purpose, the invention provides a preparation method of a photo-enzyme coupling catalytic material, which comprises the following steps:

step one, mixing GO and TiO₂Loading on a spunlace viscose fiber film;

step two, loading GO and TiO₂The spunlace viscose glueThe fiber membrane is placed in a wood vinegar bacillus culture solution to prepare the spunlace viscose fiber/GO/TiO by an in-situ growth mode₂a/BC composite fiber membrane;

step three, carrying out spunlace viscose fiber/GO/TiO₂Performing ATRP grafting modification treatment on the/BC composite fiber membrane;

step four, carrying out grafting modification on the spunlace viscose/GO/TiO₂the/BC composite fiber membrane coordinates transition metal ions;

step five, carrying out spunlace viscose fiber/GO/TiO of coordination transition metal ions₂And (3) carrying out immobilization of oxidoreductase by the aid of the/BC composite fiber membrane to obtain the photocatalytic material coupled by the aid of the light enzyme.

Preferably, GO and TiO in the first step₂The method for loading the spun-laced viscose fiber membrane comprises the steps of taking GO slices and TiO₂Forming a solution of nano particles in deionized water, performing ultrasonic oscillation to form a uniform solution, and performing suction filtration on the uniform solution by using a spunlace adhesive fiber membrane to prepare the spunlace adhesive fiber membrane/GO/TiO₂A composite fiber membrane; wherein, GO slice and TiO₂The mass-volume ratio of the nano particles to the deionized water is (0.01-0.2) g, (0.02-0.3) g:500 mL.

More preferably, the GO chips and TiO₂The mass volume ratio of the nano particles to the deionized water is (0.1-0.15) g: (0.25-0.3) g:500mL, and the uniform solution was suction filtered twice continuously with a spun-laced adhesive fibrous membrane. By adopting the proportion, the finally prepared catalytic material has higher methylene blue and active red degradation rate.

Preferably, the spunlace viscose fiber/GO/TiO is prepared in the second step₂The method for preparing the/BC composite fiber membrane comprises the following steps:

a. putting the acetobacter xylinum bacterial liquid into a fiber membrane/GO/TiO containing spunlace viscose₂Standing and culturing for 3-7 days in a culture dish of the composite fiber membrane at a constant temperature of 30 ℃;

b. taking out the spun-laced viscose fiber membrane/GO/TiO from the culture solution₂The composite fiber membrane is prepared by firstly using 0.1-0.5 mol/L NaOH solution to react for 24-48 h at the temperature of 80-100 ℃ to remove a culture medium, and then using deionized water at 60-100 DEG CRemoving redundant impurities and alkali liquor under the temperature condition, and finally carrying out freeze drying at-60 ℃ for 24-48 h to obtain the spunlace viscose/GO/TiO₂a/BC composite material.

Preferably, the composition of the culture solution of the acetobacter xylinum comprises 2.8-3.5g of tryptone, 4.9-5.5g of yeast powder and 23-25g of mannitol in each L of the culture solution.

Preferably, the method for performing ATRP graft modification treatment in step three comprises the following steps:

s1, spun-laced viscose/GO/TiO₂The initiation reaction of the/BC composite fiber membrane: firstly spunlace viscose fiber/GO/TiO₂Placing the/BC composite fiber membrane into tetrahydrofuran, stirring to remove impurities, then placing the mixture into a mixed solution of triethylamine, tetrahydrofuran and dibromo isobutyryl bromide with a volume ratio of 65-75:45-55:60-65, taking out after finishing oscillation reaction in a constant-temperature water bath kettle at 35 ℃, then cleaning with tetrahydrofuran, and storing in tetrahydrofuran;

s2, spun-laced viscose/GO/TiO₂The method comprises the following steps of (1) graft modification of a/BC composite fiber membrane:

(1) mixing N, N-dimethylacetamide and hydroxyethyltriethylenetetramine in a volume ratio of 55-60:1-2 to form a solution A;

(2) freezing hydroxyethyl methacrylate, thawing, and adding Cu₂Putting the O into hydroxyethyl methacrylate solution, and freezing and thawing the O for three times again to form solution B; the volume ratio of the hydroxyethyl methacrylate to the N, N-dimethylacetamide is 1:1, and Cu is₂The mass-volume ratio of O to hydroxyethyl methacrylate is 0.1-0.2:48-50 g/mL;

(3) respectively putting the A, B solution into a glove box in a nitrogen atmosphere, uniformly stirring the solution B after the solution B is melted, and then carrying out spunlace viscose/GO/TiO₂Placing the/BC composite fiber membrane into the mixed solution of the A and the B for reaction;

(4) the spun-laced viscose fiber/GO/TiO after reaction₂Taking out the/BC composite fiber membrane, sequentially washing with absolute ethyl alcohol and deionized water, and carrying out vacuum freeze drying to obtain the atom transfer radical modified spunlace adhesive fiber/GO/TiO₂a/BC composite fiber membrane.

It is preferable thatThe method for coordinating transition metal ions in the fourth step is to respectively prepare Fe with the concentration of 10-100 mg/L³⁺、Cu²⁺Ion solution, and then at the temperature of 25 ℃, modifying ATPR by using spunlace viscose fiber/GO/TiO₂Fe is put into the/BC composite fiber membrane respectively³⁺、Cu²⁺The ionic solution is taken out after being adsorbed for 24 hours, and then the Fe with coordination is obtained after being washed and vacuum freeze-dried³⁺、Cu²⁺And (4) forming the ionized composite fiber membrane. When Fe³⁺、Cu²⁺The concentration of the ionic solution is too low, and the catalytic performance of the finally prepared catalytic material is weaker under the same condition; when Fe³⁺、Cu²⁺When the concentration of the ionic solution is higher, the catalytic performance of the finally prepared catalytic material tends to be balanced under the same condition, and the degradation rate of methylene blue and active red is reduced.

Fe³⁺The ionic solution is preferably made of Fe₂O₃Dissolving the powder in deionized water to obtain the powder; cu²⁺The ionic solution is preferably passed over CuSO₄Completely dissolving in deionized water.

Preferably, the method for immobilizing the oxidoreductase in the fifth step includes dissolving the biological oxidoreductase in a buffer solution to prepare an enzyme solution with a concentration of 0.5-3g/L, then placing the composite fiber membrane with coordinated transition metal ions in the enzyme solution, and shaking the composite fiber membrane for 8-12 hours at the temperature of 4 ℃ to prepare the spunlace viscose fiber/GO/TiO of the immobilized enzyme₂a/BC composite fiber membrane. When the concentration of the biological enzyme solution is lower, the catalytic performance of the finally prepared catalytic material is weaker under the same condition, and when the concentration of the biological enzyme solution is 0.3g/L, the degradation rate of the catalytic material on methylene blue and active red only reaches 68.21 percent and 67.17 percent; when the concentration of the biological enzyme solution is higher, the catalytic performance of the finally prepared catalytic material tends to be balanced under the same condition, for example, when the concentration of the biological enzyme solution is 4g/L, the degradation rate of the biological enzyme solution to methylene blue and active red only reaches 96.88 percent and 97.84 percent.

The oxidoreductase is laccase, and the buffer solution is acetic acid-sodium acetate buffer solution; or the oxidoreductase is catalase, and the buffer solution is PBS buffer solution.

The invention also provides application of the photo-enzyme coupling catalytic material prepared by the preparation method of the photo-enzyme coupling catalytic material in treating dye wastewater.

The invention has the beneficial effects that:

firstly, combining the graphene oxide slices with spunlace viscose fibers by adopting a biological culture method, self-assembling and uniformly wrapping the graphene oxide slices and TiO₂Nano particles, and prepared spunlace viscose fiber/GO/TiO with good fiber form and uniform diameter₂the/BC composite fiber membrane avoids GO and TiO₂The phenomena of easy agglomeration and uniform distribution of inorganic materials on the surface of the nano-fiber can be solved, and GO and TiO can be effectively improved₂Loading and performance.

Through the combination of in-situ growth and ATRP modified immobilized enzyme, the composite fiber membrane can efficiently load the photocatalyst and the biocatalyst, so that the photocatalyst coupling catalytic material can be simply and conveniently prepared.

And thirdly, grafting a plurality of functional groups by ATRP, and then efficiently loading biological enzymes on the surfaces of three materials, namely spunlace viscose fibers, GO slices and bacterial cellulose nanofibers, by using a mode of excessive metal ion coordination, thereby improving the loading capacity and the biological catalytic activity of the enzymes.

And fourthly, the photo-enzyme coupling catalytic material can be used for quickly and efficiently degrading various dye wastewater and has excellent repeated use capability.

Drawings

In order to more clearly illustrate the embodiments of the present disclosure or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only one or more embodiments of the present disclosure, and other drawings can be obtained by those skilled in the art without creative efforts.

FIG. 1 is a spunlace viscose/GO/TiO fiber₂SEM image of/BC composite fiber membrane;

FIG. 2 is a hydroentangled viscose/GO/TiO fiber₂SEM picture of/BC composite fiber membrane immobilized enzyme;

FIG. 3 is a hydroentangled viscose/GO/TiO fiber₂EDX diagram of the/BC composite fiber membrane;

FIG. 4 is a hydroentangled viscose/GO/TiO fiber₂a/BC composite fiber membrane immobilized enzyme inverted fluorescence microscope picture.

Detailed Description

To make the objects, technical solutions and advantages of the present disclosure more apparent, the present disclosure is further described in detail below with reference to specific embodiments.

It should be noted that technical terms or scientific terms used in the embodiments of the present specification should have a general meaning as understood by those having ordinary skill in the art to which the present disclosure belongs, unless otherwise defined.

Example 1

1. 0.1g of GO chips and 0.25g of TiO were weighed₂Forming a solution of nano particles in 500mL of deionized water, forming a uniform solution after ultrasonic oscillation for 45min, and continuously filtering the uniform solution twice by adopting a spunlace viscose fiber membrane to prepare the spunlace viscose fiber membrane/GO/TiO₂And (3) compounding the fiber membrane.

2. Adopting acetobacter xylinum as a strain for culturing a bacterial cellulose membrane, accurately weighing 3g of tryptone, 5g of yeast powder and 25g of mannitol, metering to 1L by using distilled water, subpackaging in each conical flask, and sterilizing at the high temperature of 121 ℃ for 80 min. Spunlace viscose fiber/GO/TiO₂The composite fiber membrane is cut into a circle with a certain size according to the requirement, and the circle is placed in a sterile culture dish for standby after sterilization.

3. On an aseptic operation table, a liquid transfer gun is used for transferring acetobacter xylinum bacterial liquid into a container filled with spunlace viscose/GO/TiO₂The culture dish of the composite fiber membrane is statically cultured for 7 days at the constant temperature of 30 ℃.

4. Taking out the spun viscose/GO/TiO from the culture solution₂The composite fiber membrane is prepared by firstly using 0.4mol/L NaOH solution to react for 24 hours at the temperature of 80 ℃ to remove a culture medium, and then using deionized water to remove redundant impurities and alkali at the temperature of 90 DEG CFinally, freeze drying at-60 ℃ for 24h to obtain the spunlace viscose/GO/TiO₂a/BC composite fiber membrane.

5. For spunlace viscose fiber/GO/TiO₂Carrying out initiation reaction on the/BC composite fiber membrane, namely firstly carrying out spunlace viscose/GO/TiO₂And putting the/BC composite fiber membrane into Tetrahydrofuran (THF), slightly stirring for 10min to remove impurities, and taking out. Then spunlace viscose fiber/GO/TiO₂Placing the/BC composite fiber membrane in a mixed solution of 70 mu L of triethylamine, 50mL of THF and 63 mu L of dibromo isobutyryl bromide (2-BIB), shaking for 3h in a constant-temperature water bath kettle at 35 ℃, taking out after the reaction is finished, cleaning the composite fiber membrane for three times by using THF, and storing in the THF.

6. Spunlace viscose fiber/GO/TiO₂And carrying out graft modification on the/BC composite fiber membrane. Mixing 48mL of N, N Dimethylacetamide (DMF) and 800. mu.L of Hydroxyethyltriethylenetetramine (HETETA) to form a solution A; 48mL of hydroxyethyl methacrylate (HEMA) was frozen and thawed, and 0.2g of Cu was added₂Putting the O into the solution, and freezing and thawing the O for three times again to form a B solution; respectively putting the A, B solution into a glove box in nitrogen atmosphere, putting the solution B into a magnetic stirrer after the solution B is melted, stirring for 2 hours, and then carrying out spunlace on viscose/GO/TiO₂Placing the/BC composite fiber membrane into the mixed solution of the A and the B; taking out after reacting for 4h, fully washing the mixture for 3-5 times by using absolute ethyl alcohol and deionized water, and then putting the washed mixture into a vacuum freeze dryer for drying for 12h to obtain the spunlace viscose fiber/GO/TiO modified by the atom transfer radical technology₂a/BC composite fiber membrane.

7. Accurately weighing a certain mass of ferric chloride hexahydrate and copper sulfate pentahydrate, and respectively and completely dissolving in deionized water to obtain Fe with the concentration of 100mg/L³⁺、Cu²⁺An ionic solution. At 25 ℃, the ATRP modified spunlaced viscose fiber/GO/TiO₂40mL of Fe is respectively put into the/BC composite fiber membranes³⁺、Cu²⁺Dynamically adsorbing the composite material in an ion (100mg/L) solution for 24 hours, taking out the composite material, cleaning the composite material for 3-5 times by using distilled water, and drying the composite material for 24 hours by using a vacuum freeze dryer to prepare coordination Fe³⁺、Cu²⁺And (4) forming the ionized composite fiber membrane.

8. Accurately weighing a certain quantityThe laccase with the mass is dissolved in acetic acid-sodium acetate buffer solution to prepare laccase solution with the concentration of 3 g/L. Will coordinate Fe³⁺、Cu²⁺Placing the ionized composite fiber membrane into laccase solution, and preparing the spunlace viscose fiber/GO/TiO of the immobilized laccase after shaking for 12h at the temperature of 4 DEG C₂a/BC composite fiber membrane.

Example 2

1. 0.15g of GO chips and 0.3g of TiO were weighed₂Forming a solution of the nano particles in 500mL of deionized water, carrying out ultrasonic oscillation for 60min, and continuously carrying out suction filtration twice on the uniform solution by adopting the spunlace adhesive fiber membrane to prepare the spunlace adhesive fiber membrane/GO/TiO₂And (3) compounding the fiber membrane.

2. Adopting acetobacter xylinum as a strain for culturing a bacterial cellulose membrane, accurately weighing 3.5g of tryptone, 5.5g of yeast powder and 24g of mannitol, metering to 1L by using distilled water, subpackaging in each conical flask, and sterilizing at 121 ℃ for 70 min. Spunlace viscose fiber/GO/TiO₂The composite fiber membrane is cut into a circle with a certain size according to the requirement, and the circle is placed in a sterile culture dish for standby after sterilization.

3. On an aseptic operation table, a liquid transfer gun is used for transferring acetobacter xylinum bacterial liquid into a container filled with spunlace viscose/GO/TiO₂The culture dish of the composite fiber membrane is statically cultured for 6 days at the constant temperature of 30 ℃.

4. Taking out the spun viscose/GO/TiO from the culture solution₂The composite fiber membrane is prepared by firstly reacting 0.3mol/L NaOH solution at 90 ℃ for 48 hours to remove a culture medium, then removing redundant impurities and alkali liquor by using deionized water at 80 ℃, and finally freeze-drying at-60 ℃ for 36 hours to obtain the spunlace viscose/GO/TiO₂a/BC composite fiber membrane.

5. For spunlace viscose fiber/GO/TiO₂Carrying out initiation reaction on the/BC composite fiber membrane, namely firstly carrying out spunlace viscose/GO/TiO₂And putting the/BC composite fiber membrane into Tetrahydrofuran (THF), slightly stirring for 10min to remove impurities, and taking out. Then spunlace viscose fiber/GO/TiO₂the/BC composite fiber membrane is put into a mixed solution of 70 mu L of triethylamine, 50mL of THF and 63 mu L of dibromo isobutyryl bromide (2-BIB) and is kept at a constant temperature of 35 DEG CShaking in a water bath for 3h, taking out after the reaction is finished, cleaning the composite fiber membrane for three times by using THF, and storing in the THF.

6. Spunlace viscose fiber/GO/TiO₂And carrying out graft modification on the/BC composite fiber membrane. Mixing 48mL of N, N Dimethylacetamide (DMF) and 800. mu.L of Hydroxyethyltriethylenetetramine (HETETA) to form a solution A; 48mL of hydroxyethyl methacrylate (HEMA) was frozen and thawed, and 0.2g of Cu was added₂Putting the O into the solution, and freezing and thawing the O for three times again to form a B solution; respectively putting the A, B solution into a glove box in nitrogen atmosphere, putting the solution B into a magnetic stirrer after the solution B is melted, stirring for 2 hours, and then carrying out spunlace on viscose/GO/TiO₂Placing the/BC composite fiber membrane into the mixed solution of the A and the B; taking out after reacting for 4h, fully washing the mixture for 3-5 times by using absolute ethyl alcohol and deionized water, and then putting the washed mixture into a vacuum freeze dryer to dry for 12h to obtain the spunlace viscose/GO/TiO modified by the atom transfer radical technology₂a/BC composite fiber membrane.

7. Accurately weighing a certain mass of ferric chloride hexahydrate and copper sulfate pentahydrate, and respectively and completely dissolving in deionized water to obtain Fe with the concentration of 50mg/L³⁺、Cu²⁺An ionic solution. At 25 ℃, the ATRP modified spunlaced viscose fiber/GO/TiO₂40mL of Fe is respectively put into the/BC composite fiber membranes³⁺、Cu²⁺Dynamically adsorbing the composite material in an ion (50mg/L) solution for 12 hours, taking out the composite material, cleaning the composite material for 3-5 times by using distilled water, and drying the composite material for 20 hours by using a vacuum freeze dryer to prepare coordination Fe³⁺、Cu²⁺And (4) forming the ionized composite fiber membrane.

8. And (3) accurately weighing a certain mass of laccase, and dissolving the laccase in an acetic acid-sodium acetate buffer solution to prepare a laccase solution with the concentration of 1 g/L. Will coordinate Fe³⁺、Cu²⁺Placing the ionized composite fiber membrane into laccase solution, and preparing the spunlace viscose fiber/GO/TiO of the immobilized laccase after shaking for 10 hours at the temperature of 4 DEG C₂a/BC composite fiber membrane.

Example 3

1. 0.08g of GO chips and 0.2g of TiO were weighed₂The nano particles form a solution in 500mL of deionized water, and after ultrasonic oscillation for 45min, a spunlace viscose fiber film is adopted for continuous two timesPerforming secondary suction filtration on the uniform solution to prepare the spunlace viscose fiber membrane/GO/TiO₂And (3) compounding the fiber membrane.

2. Adopting acetobacter xylinum as a strain for culturing a bacterial cellulose membrane, accurately weighing 2.8g of tryptone, 4.9g of yeast powder and 23g of mannitol, metering to 1L by using distilled water, subpackaging in each conical flask, and sterilizing at 121 ℃ for 60 min. Spunlace viscose fiber/GO/TiO₂The composite fiber membrane is cut into a circle with a certain size according to the requirement, and the circle is placed in a sterile culture dish for standby after sterilization.

3. On an aseptic operation table, a liquid transfer gun is used for transferring acetobacter xylinum bacterial liquid into a container filled with spunlace viscose/GO/TiO₂The culture dish of the composite fiber membrane is statically cultured for 5 days at the constant temperature of 30 ℃.

4. Taking out the spun viscose/GO/TiO from the culture solution₂The composite fiber membrane is prepared by firstly reacting 0.45mol/L NaOH solution at 85 ℃ for 40h to remove a culture medium, then removing redundant impurities and alkali liquor by using deionized water at 100 ℃, and finally performing freeze drying at-60 ℃ for 48h to obtain the spunlace viscose/GO/TiO₂a/BC composite material.

5. For spunlace viscose fiber/GO/TiO₂Carrying out initiation reaction on the/BC composite fiber membrane, namely firstly carrying out spunlace viscose/GO/TiO₂And putting the/BC composite fiber membrane into Tetrahydrofuran (THF), slightly stirring for 10min to remove impurities, and taking out. Then spunlace viscose fiber/GO/TiO₂Placing the/BC composite fiber membrane in a mixed solution of 70 mu L of triethylamine, 50mL of THF and 63 mu L of dibromo isobutyryl bromide (2-BIB), shaking for 3h in a constant-temperature water bath kettle at 35 ℃, taking out after the reaction is finished, cleaning the composite fiber membrane for three times by using THF, and storing in the THF.

6. Spunlace viscose fiber/GO/TiO₂And carrying out graft modification on the/BC composite fiber membrane. Mixing 48mL of N, N Dimethylacetamide (DMF) and 800. mu.L of Hydroxyethyltriethylenetetramine (HETETA) to form a solution A; 48mL of hydroxyethyl methacrylate (HEMA) was frozen and thawed, and 0.2g of Cu was added₂Putting the O into the solution, and freezing and thawing the O for three times again to form a B solution; respectively putting the A, B solutions into a glove box in nitrogen atmosphere, and placing the solution B into a magnetic force after the solution B is meltedStirring for 2h on a stirrer, and then carrying out spunlacing on viscose/GO/TiO₂Placing the/BC composite fiber membrane into the mixed solution of the A and the B; taking out after reacting for 4h, fully washing the mixture for 3-5 times by using absolute ethyl alcohol and deionized water, and then putting the washed mixture into a vacuum freeze dryer to dry for 12h to obtain the spunlace viscose/GO/TiO modified by the atom transfer radical technology₂a/BC composite fiber membrane.

7. Accurately weighing a certain mass of ferric chloride hexahydrate and copper sulfate pentahydrate, and completely dissolving in deionized water to obtain Fe with the concentration of 40mg/L³⁺、Cu²⁺An ionic solution. At 25 ℃, the ATRP modified spunlaced viscose fiber/GO/TiO₂40mL of Fe is respectively put into the/BC composite fiber membranes³⁺、Cu²⁺Dynamically adsorbing the composite material in an ion (40mg/L) solution for 8 hours, taking out the composite material, cleaning the composite material for 3-5 times by using distilled water, and drying the composite material for 18 hours by using a vacuum freeze dryer to prepare coordination Fe³⁺、Cu²⁺And (4) forming the ionized composite fiber membrane.

8. Accurately weighing a certain mass of catalase, and dissolving the catalase in PBS buffer solution to prepare catalase solution with the concentration of 2 g/L. Will coordinate Fe³⁺、Cu²⁺Placing the ionized composite fiber membrane into a catalase solution, and preparing the catalase-immobilized spunlace viscose/GO/TiO after shaking for 11 hours at the temperature of 4 DEG C₂a/BC composite fiber membrane.

Comparative example 1

This comparative example differs from example 1 in that GO chips and TiO₂The amount of nanoparticles was 0.005 g. The degradation rate of the finally prepared photocatalyst coupling catalytic material to methylene blue only reaches 21.34 percent, and the degradation rate to active red only reaches 24.52 percent.

Comparative example 2

This comparative example differs from example 1 in that GO chips and TiO₂The nanoparticles were all 0.4 g. The spunlace viscose and the bacterial cellulose are difficult to self-grow to form a composite material.

Comparative example 3

The comparative example is different from example 1 in that Fe³⁺、Cu²⁺When the concentration of the ionic solution is 5mg/L, the finally prepared optical enzyme couplingThe degradation rate of the synthetic catalytic material to methylene blue only reaches 44.35 percent, and the degradation rate to active red only reaches 46.78 percent.

Comparative example 4

The comparative example is different from example 1 in that Fe³⁺、Cu²⁺When the concentration of the ionic solution is 150mg/L, the degradation rate of the finally prepared photocatalyst coupling catalytic material on methylene blue only reaches 97.45%, and the degradation rate on active red only reaches 97.66%.

Test for catalytic degradation Property

25mg of active red and methylene blue were completely dissolved in an acetic acid-sodium acetate buffer solution having a pH of 4.5, respectively, and the volume was adjusted to 500mL to prepare 50mg/L of active red and methylene blue solutions. The hydroentangled viscose fibers/GO/TiO described in example 1-2 were weighed separately₂Spunlaced viscose fiber/GO/TiO of/BC composite fiber membrane and immobilized laccase₂20mg of each/BC composite fiber membrane is put in 50mL of active red and methylene blue solution (50mg/L), photocatalytic degradation is carried out for 2h under the condition of a 300W mercury lamp, the degradation performance of the solution is measured, and the test results are shown in Table 1 by taking the spunlace viscose/BC composite fiber membrane as a control group under the same conditions. As can be seen from Table 1, spunlace viscose/GO/TiO₂The removal rate of the/BC composite fiber membrane to methylene blue solution reaches 71.16%, and the removal rate to active red solution reaches 62.88%; fe³⁺、Cu²⁺Spunlaced viscose/GO/TiO fiber of ion coordination immobilized laccase₂The removal rate of the/BC composite fiber membrane to methylene blue solution is 98.76-99.15% and 93.66-94.75%, and the removal rate to active red solution is 96.54-97.80% and 97.21-98.37% respectively; the removal rate of the control group spunlace viscose/BC composite fiber membrane on methylene blue solution reaches 17.35%, and the removal rate on active red solution reaches 18.42%; from the above experiments, it can be known that the photo-enzyme coupled catalytic material has excellent catalytic degradation performance on dye wastewater.

TABLE 1 removal of active Red and methylene blue solutions

Strength test

Hydroentangled viscose fibers/GO/TiO prepared as in examples 1-3₂According to the strength test requirements of the fiber membrane, a nanofiber membrane test sample (the specification is that the width is 10mm, and the length is 50mm) is prepared by the aid of the/BC composite fiber membrane, and a single fiber strength test is carried out by the aid of a tensile strength tester (the model is INSTRON 1185). Under the same conditions, pure BC fiber membrane and spunlace viscose/GO/TiO₂The results of the breaking strength and breaking elongation test of the/BC composite fiber membrane are shown in Table 2. The results show that the prepared spunlace viscose fiber/GO/TiO₂the/BC composite fiber membrane has the breaking strength of 41.44-43.58 MPa and the breaking elongation of 10.4-13.23%, however, the BC nano-fiber prepared under the same conditions has the maximum breaking strength of only 24.35MPa and the maximum breaking elongation of only 6.6%, so that the spunlace viscose/GO/TiO composite fiber membrane is formed by the steps of₂the/BC composite fiber membrane has excellent mechanical property.

TABLE 2 Spunlace viscose/GO/TiO fibers prepared in examples 1-3₂Test results of breaking Strength (MPa) and elongation at Break (%) of the/BC composite fiber Membrane

	Breaking Strength (MPa)	Elongation at Break (%)
			Example 1	43.58	13.23
Example 2	42.25	11.88
			Example 3	41.44	10.40

Reusability test

5 groups of active red and methylene blue with the same mass are respectively and completely dissolved in acetic acid-sodium acetate buffer solution with pH 4.5 to respectively prepare 5 groups of active red and methylene blue solutions with the concentration of 50 mg/L. The spunlace viscose fibers/GO/TiO of the immobilized laccase in the embodiment 1-2 are respectively weighed₂20mg of the/BC composite fiber membrane is put in 50mL of active red and methylene blue solution (50mg/L) and subjected to photocatalytic degradation for 2h under the condition of a 300W mercury lamp, and the degradation performance of the solution is measured. Washing the obtained product in acetic acid-sodium acetate buffer solution with pH 4.5 for 2-3 times, and treating the laccase immobilized spunlaced viscose fiber/GO/TiO under the same conditions₂the/BC composite fiber membrane is placed in active red and methylene blue solutions with the same concentration for reaction, the degraded reusability of the composite fiber membrane is measured, and the spunlace viscose/BC composite fiber membrane is used as a control group. After 5 times of repeated use, Fe³⁺、Cu²⁺Spunlaced viscose/GO/TiO fiber of ion coordination immobilized laccase₂The removal rates of the/BC composite fiber membrane to methylene blue solution are respectively 97.88% and 94.55%, and the removal rates to active red solution are respectively 96.84% and 97.68%; after 5 times of repeated use, the removal rate of the control group spunlace adhesive fiber/BC composite fiber membrane on methylene blue solution reaches 16.24%, and the removal rate on active red solution reaches 18.91%; from the above experiments, it can be known that the photo-enzyme coupled catalytic material has excellent reuse capability for dye wastewater.

Those of ordinary skill in the art will understand that: the discussion of any embodiment above is meant to be exemplary only, and is not intended to intimate that the scope of the disclosure, including the claims, is limited to these examples; within the idea of the present disclosure, also technical features in the above embodiments or in different embodiments may be combined, steps may be implemented in any order, and there are many other variations of the different aspects of the embodiments of the present description as described above, which are not provided in detail for the sake of brevity.

The embodiments of the present description are intended to embrace all such alternatives, modifications and variances that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalents, improvements, and the like that may be made within the spirit and principles of the embodiments described herein are intended to be included within the scope of the disclosure.