CN107597194A - A kind of preparation method of new ZnO/ fungies fiber optic catalytic composite material - Google Patents

Abstract

The invention discloses a preparation method of a novel ZnO/fungus fiber photocatalytic composite material, which relates to a preparation method of a novel fungus fiber composite material which photodegrades an organic dye. The method of the invention uses zinc acetate, hexamethylenetetramine and fungal fiber as reactants, and adopts a solvothermal synthesis method to prepare a novel ZnO/fungal fiber composite fiber material. Zinc acetate and hexamethylenetetramine were added to ethanol-treated fungal fibers, and ZnO/fungus fiber composite fiber materials were obtained through ultrasonication, solvothermal synthesis and freeze-drying. A layer of spherical ZnO nanoparticles with a particle size of about 600nm is attached to the surface of the fungal fiber, and the fungal fiber acts as a good template. Generation of ZnO particles on the surface of fungal fibers to improve their thermal stability. Using 5mg/L Rhodamine B solution for photocatalytic experiments, the photocatalytic degradation effect of ZnO/fungal fiber composite fiber material on Rhodamine B dye can reach 92.28%.

Description

Preparation method of a new ZnO/fungus fiber photocatalytic composite material

technical field

The invention relates to a preparation method of a novel ZnO/fungus fiber photocatalytic composite material.

Background technique

With the improvement of people's living standards, more and more dyes are widely used in printing and dyeing, papermaking, textile and other industries. With the rapid development of the industry and the improvement of economic benefits, the discharge of dye wastewater has brought serious harm to the environment. Dye wastewater has the characteristics of large chroma, complex composition, toxicity, high chemical stability, carcinogenicity, teratogenicity and mutagenicity. At present, the main methods of treating dye wastewater are roughly divided into chemical methods, physical methods, biological methods and adsorption methods. Physical and chemical methods have high operating costs and complicated processes, and some harmful gases are likely to be generated during the treatment process, and these gases are discharged into the air to cause secondary hazards. Biological methods mainly use bacteria and fungi to decolorize and degrade dyes. Relatively speaking, there are certain requirements for the type, temperature and pH of dyes, which limits the scope of application. The adsorption method is simple to operate, has strong adaptability, and does not require a lot of manpower and material resources. It is generally regarded as a way to quickly purify dye wastewater. The focus of the adsorption method is to find a suitable adsorbent. A good adsorbent generally requires a large specific surface area, a suitable pore structure, a good adsorption capacity, stable properties during the adsorption process, a wide range of raw material sources, convenient preparation, and effective adsorption. Good mechanical strength, can be recycled, etc. Today, with increasing environmental pressure, it is particularly important to use environmentally friendly and degradable adsorbent materials. At present, semiconductor inorganic nanomaterials are also widely used in the preparation of polymer materials, which can play a role in functional modification and mechanical property modification of polymer materials. Semiconductor photocatalysts can undergo oxidation-reduction reactions under light irradiation, and degrade organic pollutants into small molecules such as water, carbon dioxide, salts, and acids, thereby reducing environmental pollution.

Plant cellulose and bacterial cellulose have been widely used as biological templates. Studies have found that fungi can produce a three-dimensional network fiber structure similar to bacterial cellulose in the process of biological culture, and the fiber material with a large number of reactive groups on the surface is called fungal fiber. Fungal fibers have a three-dimensional network structure similar to bacterial cellulose and active sites of polyhydroxyl groups, and can be compounded and doped with various types of semiconductor nanoparticles to fix them on each reaction site of the microfibers and avoid interaction with each other. The collision and agglomeration of nano-materials solve the stability problem of nano-materials and ensure the nano-effects. The development of semiconductor particles with high photocatalytic efficiency and their composite materials, as well as supported organic-inorganic composite photocatalytic materials, has important theoretical significance and practical value for the large-scale application of semiconductor photocatalysts in industry. In this experiment, fungal fiber, zinc acetate and thiourea were used as raw materials to prepare a new material with photocatalytic dye adsorption and degradation by solvothermal synthesis. This experiment has the advantages of simple operation, easy-to-obtain product, biodegradable, low cost, and strong adaptability to the environment.

Contents of the invention

The invention provides a preparation method of a novel ZnO/fungus fiber photocatalytic composite material to solve the current problems of serious discharge of printing and dyeing wastewater, high production cost, difficult degradation of products and the like.

A kind of preparation method of novel ZnO/fungal fiber photocatalytic composite material of the present invention, specifically carry out according to the following steps: 1, fungal mycelia, boil 10-30min with 0.1%～2% dilute lye, filter, obtain fungal fiber , washed with deionized water until neutral, freeze-dried for later use. 2. Prepare a series of ethanol solutions with a gradient concentration of 40% to 99% to soak the fungal fibers swollen with deionized water, and then perform centrifugal separation on the fungal fibers at a centrifugal speed of 5000 to 10000 rpm. 3. Add the centrifuged fungal fiber to zinc acetate solution (the ratio of fungal fiber to zinc acetate is 1:0.1～1:3) as the zinc source and thiourea (the molar ratio of thiourea-ethanol solution is 1:2) ~1:10) in ethanol mixed solution as precipitating agent, carry out magnetic dispersion at room temperature; 4. Move the mixture into a stainless steel reaction kettle with polytetrafluoroethylene lining, and keep it warm at 80~200°C for 6~ 10h; 5. After the reaction, the temperature was lowered to room temperature, and the mixed solution was centrifuged (6000-10000rpm), and the new ZnO/ Fungal fiber composites.

A layer of spherical ZnO nanoparticles is attached to the surface of the fungal fiber prepared by the present invention, the particle size is about 600nm, and the distribution is uniform, and the fungus plays a good template role; there is an interaction between the active groups on the surface of the fungal fiber and the ZnO nanoparticles, It is beneficial to improve the stability of ZnO particles on the surface of fungal fibers. The photocatalytic degradation efficiency can reach 92.28% in 5mg/L rhodamine B solution. The preparation technology of the invention is simple, easy to operate, environmentally friendly, pollution-free, and biodegradable, and the production process is environmentally friendly and conforms to the concept of sustainable green development.

detailed description

Example 1:

A kind of preparation method of the ZnO/fungal fiber novel composite material of photocatalysis of the present invention, specifically carry out according to the following steps: with 0.1%～2% dilute lye, boil 10～30min with 2.0g fungal mycelium, filter, The fungal fibers were obtained, washed with deionized water until neutral, and freeze-dried for later use; a series of ethanol solutions with a gradient concentration of 40% to 99% were prepared to soak the fungal fibers swollen by deionized water, and then the fungal fibers were centrifuged. The centrifugal speed is 5000～10000rpm; the centrifugally separated fungal fiber is added to the ethanol mixed solution with zinc acetate solution as zinc source (the dosage ratio of fungal fiber and zinc acetate is 1:0.1～1:3) and thiourea as precipitant , carry out magnetic dispersion at room temperature; move the mixture into a stainless steel reactor with polytetrafluoroethylene lining, and keep it warm at 80-200°C for 6-10 hours; after the reaction, cool down to room temperature, and mix the solution Perform centrifugal separation (6000-10000rpm), repeatedly wash with absolute ethanol and deionized water, and freeze-dry to obtain a novel composite fiber material with photocatalytic degradation.

Example 2

Boil 2.0 g of fungal mycelium with 5% dilute lye for 30 minutes, filter to obtain fungal fibers, wash with deionized water until neutral, and freeze-dry for later use; prepare a series of ethanol solutions with a concentration gradient of 40% to 99% Soak the fungal fibers swollen with deionized water, then centrifuge the fungal fibers at a centrifugal speed of 8000rpm; add the fungal fibers to zinc acetate solution as the zinc source (the ratio of fungal fiber to zinc acetate is 1:0.1) ~1:3) and ethanol mixed solution with thiourea as precipitating agent, carry out magnetic dispersion at room temperature; move the mixture into a flask, and keep it at 95°C for 6h; after the reaction, the temperature is lowered to room temperature, and The mixed solution is subjected to centrifugation (6000-10000rpm), washed repeatedly with absolute ethanol and deionized water, and freeze-dried to obtain a novel composite fiber material with photocatalytic degradation. The experimental results showed that there was no formed ZnO on the surface of the fungal fiber, and the adhesion on the surface was less. The photocatalytic degradation effect in 5mg/L rhodamine B solution is poor.

Example 3

Boil 2 g of fungal mycelium with 0.5% dilute lye for 20 minutes, filter to obtain fungal fibers, wash with deionized water until neutral, and freeze-dry for later use; prepare a series of ethanol solutions with a concentration gradient of 40% to 99% for soaking Treat the fungal fibers swollen with deionized water, and then centrifuge the fungal fibers at a centrifugal speed of 5000rpm; take 0.5g of ZnO nanoparticles and disperse them in deionized water, and perform ultrasonic dispersion for 30min; take 0.1g of fungal fibers, and dissolve the ZnO suspension It is sprayed onto the surface of cellulose to obtain a novel composite fiber material with photocatalytic degradation. The material prepared by this method has less residue on the surface of the fungal fiber and is easy to fall off.

Example 4

Boil 2 g of fungal mycelium with 0.5% dilute lye for 30 minutes, filter to obtain fungal fibers, wash with deionized water until neutral, and freeze-dry for later use; prepare a series of ethanol solutions with a concentration gradient of 40% to 99% for soaking Treat the fungal fibers swollen with deionized water, then centrifuge the fungal fibers at a centrifugal speed of 6000rpm; add the fungal fibers to the zinc nitrate solution as the zinc source (the ratio of fungal fiber to zinc acetate is 1:0.1) and ethanol mixed solution with ammonia water as precipitant, magnetically dispersed at room temperature; the mixture was moved into a stainless steel reaction kettle with polytetrafluoroethylene lining, and kept at 150°C for 4 hours; after the reaction, the temperature dropped After reaching room temperature, the mixed solution was centrifuged (7000 rpm), washed repeatedly with absolute ethanol and deionized water, and freeze-dried to obtain a novel composite fiber material with photocatalytic degradation. Experiments showed that the smooth surface of fungal fibers vaguely formed some irregular oblate particles with poor uniformity and no nucleation and growth into spherical particles. The photocatalytic degradation effect in 5mg/L Rhodamine B solution is only 61.13%.

Example 5

Boil 2 g of fungal mycelium with 0.5% dilute lye for 30 minutes, filter to obtain fungal fibers, wash with deionized water until neutral, and freeze-dry for later use; prepare a series of ethanol solutions with a gradient concentration of 40%-99% for soaking Treat the fungal fibers swollen with deionized water, then centrifuge the fungal fibers at a centrifugal speed of 5000rpm; add the fungal fibers to the zinc nitrate solution as the zinc source (the ratio of fungal fiber to zinc acetate is 1:1.5) And in the ethanol mixed solution with ammonia water as the precipitating agent, adjust the pH with 1mol/L sodium hydroxide solution, and carry out magnetic dispersion at room temperature; move the mixture into a stainless steel reaction kettle with a polytetrafluoroethylene liner, at 100 ° C Keep the reaction at high temperature for 10 hours; after the reaction, the temperature is lowered to room temperature, and the mixed solution is centrifuged (6000rpm), washed repeatedly with absolute ethanol and deionized water, and freeze-dried to obtain a new type of composite fiber with photocatalytic degradation Material. Experiments showed that the smooth surface of fungal fibers formed spherical ZnO nanoparticles with uniform particle size distribution. The photocatalytic degradation effect in 5mg/L rhodamine B solution reached 69.48%.

Example 6

Boil 2 g of fungal mycelium with 0.5% dilute lye for 30 minutes, filter to obtain fungal fibers, wash with deionized water until neutral, and freeze-dry for later use; configure a series of ethanol solutions to soak in deionized water fungal fiber, the fungal fiber is centrifuged, and the centrifugal speed is 8000rpm; the fungal fiber and the fungal fiber with a zinc acetate dosage ratio of 1:2 are added to the zinc acetate solution, and thiourea is used as the ethanol mixed solution of the precipitating agent. Mechanical stirring was carried out at room temperature; the mixture was moved into the reaction kettle, and kept at 120°C for 8 hours; after the reaction, it was centrifuged, and then washed repeatedly with absolute ethanol and deionized water, and after freeze-drying, a photocatalytic degradation product was obtained. A new type of composite fiber material. Experiments show that spherical ZnO nanoparticles are formed on the smooth surface of the fungal fiber, the particle size is about 600nm and the distribution is uniform, and the fungus plays a good role as a template. The photocatalytic degradation effect in 5mg/L rhodamine B solution reached 73.47%.

Claims (8)

1. A kind of preparation method of novel ZnO/fungal fiber photocatalytic composite material, its preparation method is carried out by the following steps: one, fungal mycelia, boil a certain hour with dilute lye, filter and obtain fungal fiber, use deionized water Wash until neutral, and freeze-dry for later use. 2. Prepare a series of ethanol solutions with gradient concentrations to soak the fungal fibers swollen with deionized water, and then perform centrifugal separation on the fungal fibers. 3. The fungal fibers separated by centrifugation are added to the ethanol mixed solution with zinc acetate solution as the zinc source and thiourea as the precipitant, and magnetically dispersed at room temperature; In the reaction kettle, keep warm at a certain temperature and react for a certain period of time; 5. After the reaction is completed, the temperature is lowered to room temperature, and the mixed solution is centrifuged, washed repeatedly with absolute ethanol and deionized water, and obtained after freeze-drying. Novel ZnO/fungus fiber composites for degradation. 2. The preparation method of a novel ZnO/fungus fiber photocatalytic composite material according to claim 1, characterized in that in step 1, the concentration of dilute lye is 0.1% to 2%, and the boiling time is 10 to 30 minutes. 3. The preparation method of a novel ZnO/fungus fiber photocatalytic composite material according to claim 1, characterized in that the series concentration of the ethanol solution in step 2 is about 40%-99%. 4. The preparation method of a novel ZnO/fungus fiber photocatalytic composite material according to claim 1, characterized in that the rotational speed of centrifugation in step 2 is 5000-10000rpm. 5. The preparation method of a novel ZnO/fungal fiber photocatalytic composite material according to claim 1, characterized in that in step 3, zinc acetate is the zinc source, and the dosage ratio of fungal fiber to zinc acetate is 1:0.1～1 :3. 6. The preparation method of a novel ZnO/fungus fiber photocatalytic composite material according to claim 1, characterized in that thiourea is a precipitating agent in step 3, wherein the molar ratio of thiourea-ethanol solution is 1:2～1 :10. 7. The preparation method of a novel ZnO/fungus fiber photocatalytic composite material according to claim 1, characterized in that in step 4, the reaction temperature is 80-200° C., and the reaction time is 6-12 hours. 8. A method for preparing a novel ZnO/fungus fiber photocatalytic composite material according to claim 1, characterized in that in step 3, the mixed solution is centrifuged at 6000-10000rpm.