A green and efficient sewage treatment catalyst and its preparation method
Patent Information
- Application Number
- CN202410875963.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-02
- Publication Date
- 2024-12-06
- Estimated Expiration
- 2044-07-02
AI Technical Summary
The existing green sewage treatment catalysts have shortcomings in terms of stability and catalytic performance, which are difficult to meet the requirements of environmental protection and sustainable development, and may cause secondary pollution during the treatment process.
Using modified CuO-ZnO composition, coral calcium powder, green algae powder and rhodium oxide, the particle size and surfactant are controlled through surfactant-assisted preparation and plasma modification, and the particle size and surfactant sites are controlled, combined with nitrogen calcination and low-temperature mixing to prepare Catalysts with high catalytic efficiency and stability are produced.
It significantly improves the catalytic efficiency and stability of the catalyst, achieves efficient wastewater purification, conforms to the concept of green chemistry, and reduces production costs.
Abstract
Description
Technical Field
[0001] The invention belongs to the technical field of sewage treatment and relates to a green and efficient sewage treatment catalyst and a preparation method thereof. Background Art
[0002] Green wastewater treatment catalyst is a treatment technology that plays a vital role in wastewater treatment. It can effectively degrade organic matter and remove pollutants, thereby purifying water.
[0003] Green wastewater treatment catalysts reduce the energy requirements of chemical reactions by providing activation energy and accelerate the reaction rate. In the process of wastewater treatment, catalysts convert organic matter into harmless substances through processes such as adsorption, dissociation, surface reaction and regeneration. Common green wastewater treatment catalysts include metal catalysts, oxide catalysts and biocatalysts. Among them, biocatalysts are methods of degrading and oxidizing organic matter by introducing microorganisms into wastewater treatment systems. Chemical catalysts refer to a class of chemical substances that can play a catalytic role in wastewater through artificial synthesis. Green wastewater treatment catalysts are not only used in the field of wastewater treatment, but also widely used in drinking water treatment, industrial wastewater treatment, agricultural water treatment and seawater desalination. At the same time, for environmental protection and sustainable development, the selection and production of green catalysts are also crucial. Non-toxic, harmless and environmentally friendly materials should be selected to avoid secondary pollution during the treatment process. Summary of the invention
[0004] The purpose of the present invention is to provide a green and efficient sewage treatment catalyst and a preparation method thereof, which has the characteristics of good catalytic performance and high stability.
[0005] The purpose of the present invention can be achieved through the following technical solutions:
[0006] A green and efficient sewage treatment catalyst, the catalyst formula is as follows, by weight, 40-50 parts of modified CuO-ZnO composition, 30-40 parts of green algae powder, 10-15 parts of coral calcium powder, 3-5 parts of rhodium oxide, 3-5 parts of dispersant, 1-2 parts of coupling agent,
[0007] The preparation process of the modified CuO-ZnO composition is as follows:
[0008] S1: copper nitrate and zinc nitrate were mixed in a molar ratio of 5:3, and after mixing evenly, 1 wt% of citric acid was added, and the mixture was ground at a speed of 200 r / min for 0.5 h to obtain a mixture A;
[0009] S2: adding 0.5 wt % of polyethylene glycol-2000 to mixture A, continuing grinding for 0.5 h, and performing ultrasound at room temperature for 1 h to obtain mixture B;
[0010] S3: Dry the mixture B at 110°C for 24 hours, and then place it in a muffle furnace for calcination. The temperature is raised from room temperature to 400°C at a rate of 5°C / min, and calcined at 400°C for 4 hours. The temperature is then lowered to room temperature at a rate of 2°C / min, and allowed to stand for 12 hours to obtain a mixture C.
[0011] S4: Grinding the mixture C with an agate ball mill at a grinding speed of 500 r / min for 2 h to obtain a CuO-ZnO composite;
[0012] S5: Plasma modification is performed on the CuO-ZnO composition obtained in S4. The modification parameters are: at room temperature, argon-hydrogen mixed gas is used as the gas source, the gas flow rate is 50 ml / min, the radio frequency is 50 KHz, and the working time is 5 min to obtain a modified CuO-ZnO composition.
[0013] Furthermore, the dispersant is polyethylene glycol with a molecular weight ranging from 10,000 to 20,000.
[0014] Furthermore, the coupling agent is one or more of chitosan and polyurethane.
[0015] Furthermore, the CuO-ZnO composition prepared in S4 has a particle size of 200 mesh.
[0016] Furthermore, the gas proportion in the argon-hydrogen mixed gas in S5 is 92% argon and 8% hydrogen.
[0017] A method for preparing a green and efficient sewage treatment catalyst, the specific process of the preparation method is as follows:
[0018] S61: Mix the modified CuO-ZnO composition, coral calcium powder and rhodium oxide in proportion, and purge with nitrogen at a flow rate of 10 m / s for 2 h at 50° C. to obtain a mixture D;
[0019] S62: calcining the mixture D twice in a nitrogen atmosphere, heating from 50°C to 300°C at a rate of 5°C / min for 3 hours, and then slowly cooling to room temperature at a rate of 2°C / min after calcination to obtain a mixture E;
[0020] S63: Cooling the mixture E to 15° C., adding green algae powder, dispersant and coupling agent in proportion, grinding the mixture with a ball mill at a speed of 200 r / min for 1 h at a grinding temperature of 15° C., to obtain the catalyst.
[0021] Furthermore, the prepared catalyst is stored in a light-proof environment at 25° C. and a humidity of 30%.
[0022] The present invention adopts surfactant to assist in preparing CuO-ZnO composition. In the preparation process, the particle size of the prepared composition is better controlled by adding surfactant. Polyethylene glycol-2000 is used as a non-ionic surfactant and is adsorbed on the gaps between the compositions through van der Waals force to generate osmotic hydration force to break the particles. In order to better improve the penetration of the surfactant, citric acid is also added in the present invention. Citric acid and polyethylene glycol-2000 will produce a synergistic effect, reduce the agglomeration force between the particles, make the particles easier to break, and then make the prepared composition have better dispersibility and smaller particle size. In the present invention, 400°C is selected to first roast the CuO-ZnO composition. Roasting at this temperature can completely remove citric acid and polyethylene glycol-2000, and will not cause sintering of the prepared CuO-ZnO composition.
[0023] The high energy and high reactivity of plasma cause the atoms and molecules on the surface of the composition to undergo chemical reactions, physical collisions and structural changes, thereby increasing the number and activity of active sites on the surface of the composition and improving the catalytic efficiency of the catalyst prepared using the composition; in addition, the surface of the composition after plasma treatment can form a more stable structure, which helps to resist the adverse effects of the external environment, such as high temperature, high pressure or corrosive substances.
[0024] In order to better improve the performance of the catalyst, coral calcium powder is also added in the present invention. The addition of this substance can provide a large number of reaction sites to promote the reaction. Coral calcium powder has antioxidant properties, which helps to reduce the generation of free radicals and protect the catalyst from oxidative damage. In the catalytic reaction, this antioxidant property may help to extend the service life of the catalyst and improve the catalytic efficiency. At the same time, this antioxidant property will also enhance the stability of the catalyst to prevent it from being deactivated or decomposed during the reaction. The mixing and roasting process of the metal composition and coral calcium powder will change the surface structure and electronic state of the catalyst, thereby affecting the selectivity of the catalytic reaction. Coral calcium powder has excellent heat resistance and chemical stability. After mixing it with the metal composition and undergoing secondary roasting, the prepared catalyst will show higher thermal stability and chemical stability. In the present invention, the secondary roasting is carried out at 300°C. The roasting treatment at this temperature can remove impurities and surface adsorbed substances. In addition, during the nitrogen atmosphere roasting, due to the protection of nitrogen, the active components basically do not aggregate, but only enhance the interaction between the active components, making the prepared catalyst more stable.
[0025] As a natural biomaterial, green algae can be added to the catalyst to help achieve the environmental protection and sustainability of the catalyst, which is in line with the concept of green chemistry. In addition, green algae are abundant in resources and grow rapidly, which is conducive to reducing the production cost of the catalyst. As a catalyst, the CuO-ZnO composition will exhibit acid-base properties in the catalytic reaction, and promote the reaction by adsorbing reactants and providing active sites. This process can be regarded as a manifestation of acidity and alkalinity. Green algae contain a large number of metal elements, such as iron, zinc, potassium, calcium, etc. These metal elements can interact with the CuO-ZnO composition catalyst that exhibits acid-base properties, coordinate and exchange with the active sites on the catalyst surface, change the properties and structure of the catalyst surface, thereby improving the activity and selectivity of the catalyst. Therefore, the addition of green algae can significantly improve the efficiency of the catalytic reaction. At the same time, the CuO-ZnO composition can improve the efficiency of photosynthesis by optimizing the electron transport chain in green algae. Photosynthesis is the process by which green algae convert light energy into chemical energy. Optimizing this process helps green algae to utilize light energy more efficiently, improves the efficiency of converting light energy into chemical energy, and promotes efficient utilization of energy in green algae. In the present invention, in order to avoid inactivation of green algae, during the preparation process, the reaction temperature of the green algae and the metal composition is controlled to be 15°C.
[0026] As a highly active catalyst, rhodium oxide has a fast catalytic reaction rate and high catalytic efficiency. In the sewage treatment process, rhodium oxide can effectively accelerate the chemical reaction, promote the decomposition and conversion of harmful substances, thereby improving the sewage treatment efficiency. Therefore, rhodium oxide is also added in the present invention to further improve the performance of the catalyst.
[0027] Beneficial effects of the present invention:
[0028] The present invention adopts surfactant to assist in preparing CuO-ZnO composition, and controls the roasting temperature to make the prepared composition have better dispersibility and smaller particle size, and then uses plasma to increase the number and activity of active sites on the surface of the composition, thereby improving the catalytic efficiency of the catalyst prepared by the composition; coral calcium powder is also added in the present invention, and the coral calcium powder is mixed with the metal composition and then roasted twice under nitrogen, thereby improving the thermal stability and chemical stability of the prepared catalyst; green algae and the modified CuO-ZnO composition are mixed in the present invention, and the addition of green algae can improve the activity and selectivity of the catalyst, and the CuO-ZnO composition can optimize the electron transport chain in the green algae, improve the efficiency of photosynthesis, and promote the efficient utilization of energy in the green algae, and adding green algae to the catalyst is conducive to achieving environmental protection and sustainability of the catalyst, which is in line with the concept of green chemistry. DETAILED DESCRIPTION
[0029] In order to further illustrate the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the specific implementation methods, structures, features and effects of the present invention are described in detail below in combination with the embodiments.
[0030] The determination standard of the present invention refers to HJ 91.1-2019 "Technical Specifications for Sewage Monitoring", and samples are taken of untreated sewage and sewage treated with the catalyst of the present invention, and the components of the two are tested to obtain the sewage purification rate.
[0031] Formula ratio 1: 40 parts of modified CuO-ZnO composition, 40 parts of green algae powder, 10 parts of coral calcium powder, 5 parts of rhodium oxide, 3 parts of polyethylene glycol-20000, and 2 parts of chitosan;
[0032] Formula ratio 2: 50 parts of modified CuO-ZnO composition, 30 parts of green algae powder, 10 parts of coral calcium powder, 5 parts of rhodium oxide, 3 parts of polyethylene glycol-20000, and 2 parts of chitosan;
[0033] Formula ratio 3: 45 parts of modified CuO-ZnO composition, 30 parts of green algae powder, 15 parts of coral calcium powder, 3 parts of rhodium oxide, 5 parts of polyethylene glycol-20000, and 2 parts of chitosan;
[0034] Formula ratio 4: 40 parts of modified CuO-ZnO composition, 35 parts of green algae powder, 15 parts of coral calcium powder, 4 parts of rhodium oxide, 5 parts of polyethylene glycol-10000, and 1 part of chitosan;
[0035] The preparation process of the modified CuO-ZnO composition is as follows:
[0036] S1: copper nitrate and zinc nitrate were mixed in a molar ratio of 5:3, and after mixing evenly, 1 wt% of citric acid was added, and the mixture was ground at a speed of 200 r / min for 0.5 h to obtain a mixture A;
[0037] S2: adding 0.5 wt % of polyethylene glycol-2000 to mixture A, continuing grinding for 0.5 h, and performing ultrasound at room temperature for 1 h to obtain mixture B;
[0038] S3: Dry the mixture B at 110°C for 24 hours, and then place it in a muffle furnace for calcination. The temperature is raised from room temperature to 400°C at a rate of 5°C / min, and calcined at 400°C for 4 hours. The temperature is then lowered to room temperature at a rate of 2°C / min, and allowed to stand for 12 hours to obtain a mixture C.
[0039] S4: Grinding the mixture C with an agate ball mill at a grinding speed of 500 r / min for 2 h to obtain a CuO-ZnO composite;
[0040] S5: Plasma modification is performed on the CuO-ZnO composition obtained in S4. The modification parameters are: at room temperature, argon-hydrogen mixed gas is used as the gas source, the gas flow rate is 50 ml / min, the radio frequency is 50 KHz, and the working time is 5 min to obtain a modified CuO-ZnO composition.
[0041] Example 1
[0042] S61: Mix the modified CuO-ZnO composition, coral calcium powder and rhodium oxide according to the formula ratio 1, and purge with nitrogen at a flow rate of 10 m / s for 2 h at 50° C. to obtain a mixture D;
[0043] S62: calcining the mixture D twice in a nitrogen atmosphere, heating from 50°C to 300°C at a rate of 5°C / min for 3 hours, and then slowly cooling to room temperature at a rate of 2°C / min after calcination to obtain a mixture E;
[0044] S63: Cooling the mixture E to 15° C., adding green algae powder, dispersant and coupling agent according to the formula ratio 1, grinding with a ball mill at a speed of 200 r / min for 1 h, and the grinding temperature is 15° C. to obtain the catalyst.
[0045] The sewage purification rate of the catalyst in this embodiment is 99.5%.
[0046] Example 2
[0047] This embodiment uses formula ratio 2 to prepare the catalyst, and the remaining steps are consistent with those of embodiment 1. The sewage purification rate of the catalyst in this embodiment is 99.3%.
[0048] Example 3
[0049] This embodiment uses the formula ratio 3 to prepare the catalyst, and the remaining steps are the same as those of embodiment 1. The sewage purification rate of the catalyst in this embodiment is 99.7%.
[0050] Example 4
[0051] This embodiment uses formula ratio 4 to prepare the catalyst, and the remaining steps are the same as those of embodiment 1. The sewage purification rate of the catalyst in this embodiment is 98.6%.
[0052] Comparative Example 1
[0053] In this comparative example, the CuO-ZnO composition was not plasma modified, and the remaining steps were the same as those in Example 3. The purification rate of the catalyst in this comparative example for sewage was 96.5%.
[0054] Comparative Example 2
[0055] In this comparative example, no green algae powder is added, and the formula ratio is 75 parts of modified CuO-ZnO composition, 15 parts of coral calcium powder, 3 parts of rhodium oxide, 5 parts of polyethylene glycol-20000, and 2 parts of chitosan, and the remaining steps are consistent with Example 3. The purification rate of the catalyst in this comparative example for sewage is 92.9%.
[0056] Comparative Example 3
[0057] In this comparative example, coral calcium powder is not added, and the formula ratio is 60 parts of modified CuO-ZnO composition, 30 parts of green algae powder, 3 parts of rhodium oxide, 5 parts of polyethylene glycol-20000, and 2 parts of chitosan. The remaining steps are consistent with Example 3. The purification rate of the catalyst in this example for sewage is 94.7%.
[0058] It can be seen from experiments that embodiment 3 is the best embodiment.
[0059] When the present invention is used:
[0060] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Although the present invention has been disclosed as a preferred embodiment as above, it is not used to limit the present invention. Any technical personnel in this field can make some changes or modify the technical contents disclosed above into equivalent embodiments without departing from the scope of the technical solution of the present invention. However, any brief modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of the technical solution of the present invention.
Claims
1. A green and efficient sewage treatment catalyst, It is characterized in that The catalyst formula is as follows: by weight, 40 to 50 parts of modified CuO-ZnO composition, 30 to 40 parts of green algae powder, 10 to 15 parts of coral calcium powder, 3 to 5 parts of rhodium oxide, 3 to 5 parts of dispersant, and 1 to 2 parts of coupling agent. The preparation process of the modified CuO-ZnO composition is as follows: S1: copper nitrate and zinc nitrate were mixed in a molar ratio of 5:3, and after mixing evenly, 1 wt% of citric acid was added, and the mixture was ground at a speed of 200 r / min for 0.5 h to obtain a mixture A; S2: adding 0.5 wt % of polyethylene glycol-2000 to mixture A, continuing grinding for 0.5 h, and performing ultrasound at room temperature for 1 h to obtain mixture B; S3: Dry the mixture B at 110°C for 24 hours, and then place it in a muffle furnace for calcination. The temperature is raised from room temperature to 400°C at a rate of 5°C / min, and calcined at 400°C for 4 hours. The temperature is then lowered to room temperature at a rate of 2°C / min, and allowed to stand for 12 hours to obtain a mixture C. S4: Grinding the mixture C with an agate ball mill at a grinding speed of 500 r / min for 2 h to obtain a CuO-ZnO composite; S5: Plasma modification is performed on the CuO-ZnO composition obtained in S4. The modification parameters are: at room temperature, argon-hydrogen mixed gas is used as the gas source, the gas flow rate is 50 ml / min, the radio frequency is 50 KHz, and the working time is 5 min to obtain a modified CuO-ZnO composition.
2. A green and efficient sewage treatment catalyst according to claim 1, It is characterized in that The dispersant is polyethylene glycol, and the molecular weight ranges from 10,000 to 20,000.
3. A green and efficient sewage treatment catalyst according to claim 1, It is characterized in that The coupling agent is one or more of chitosan and polyurethane.
4. A green and efficient sewage treatment catalyst according to claim 1, It is characterized in that The particle size of the CuO-ZnO composite prepared in S4 is 200 mesh.
5. A green and efficient sewage treatment catalyst according to claim 1, It is characterized in that The gas proportion in the argon-hydrogen mixed gas in S5 is 92% argon and 8% hydrogen.
6. A method for preparing a green and efficient sewage treatment catalyst, based on a green and efficient sewage treatment catalyst according to any one of claims 1 to 5, It is characterized in that The specific process of the preparation method is as follows: S61: Mix the modified CuO-ZnO composition, coral calcium powder and rhodium oxide in proportion, and purge with nitrogen at a flow rate of 10 m / s for 2 h at 50° C. to obtain a mixture D; S62: calcining the mixture D twice in a nitrogen atmosphere, heating from 50°C to 300°C at a rate of 5°C / min for 3 hours, and then slowly cooling to room temperature at a rate of 2°C / min after calcination to obtain a mixture E; S63: Cooling the mixture E to 15° C., adding green algae powder, dispersant and coupling agent in proportion, grinding the mixture with a ball mill at a speed of 200 r / min for 1 h at a grinding temperature of 15° C., to obtain the catalyst.
7. A method for preparing a green and efficient sewage treatment catalyst according to claim 6, It is characterized in that The prepared catalyst is stored in a light-proof environment at 25° C. and a humidity of 30%.