Preparation method of multifunctional zeolite-based environmentally friendly coating

Abstract

The invention discloses a preparation method of a multifunctional zeolite-based environmentally friendly coating, comprising the following steps: 1. mixing zeolite and an inorganic acid solution to react, filtering, washing, drying and grinding to obtain defect-rich high-silicon zeolite; 2. mixing the defect-rich high-silicon zeolite and water, then adding copper salt and titanium salt solutions, and adjusting the pH value to be weakly alkaline. After the reaction, aging, filtering, washing, drying and grinding, collecting the product, placing it in a muffle furnace, and calcining it at 400-800° C. for 4-6 hours to obtain an adsorption / visible light photocatalytic zeolite-based material; 3. mixing the adsorption / visible light photocatalytic zeolite-based material and an antibacterial agent precursor solution containing silver ions, and after the reaction, reducing the silver ions to elemental silver by a reduction method to obtain an adsorption / visible light photocatalytic / antibacterial zeolite-based material; and 4. uniformly mixing the rubber powder, the adsorption / visible light photocatalytic / antibacterial zeolite-based material and an inorganic filler to obtain a multifunctional zeolite-based environmentally friendly coating with excellent adsorption, visible light catalytic and antibacterial properties.

Description

Technical Field

[0001] The invention relates to zeolite-based modification, in particular to a method for preparing a multifunctional zeolite-based environmentally friendly coating. Background Art

[0002] At present, the country and society have begun to vigorously advocate the protection of the ecological environment, energy conservation and emission reduction, and sustainable development. Architectural coatings have begun to shift towards functionality, environmental protection, and decorative properties. In particular, the requirements for environmental protection are becoming increasingly higher. Various types of inorganic, water-based, powder, high-solid, solvent-free, radiation-cured and other environmentally friendly coatings with zero / low VOCs content have emerged and are gradually replacing solvent-based coatings to reduce the generation of VOCs at the source. At the same time, most domestic and foreign coatings companies have involved antibacterial coating products, such as Akzo Nobel's antibacterial Interpon AM series, which can reduce up to 99.99% of bacteria and mold, making it easier to maintain hygiene and cleanliness and reduce the risk of pollution. In addition, a large number of domestic coatings companies such as Sankeshu, Zijinhua, Dulux and Carpoly have also successively launched various antibacterial coatings.

[0003] In recent years, zeolite-based environmentally friendly coatings have garnered increasing attention due to their non-toxic, environmentally friendly, and stable properties. Zeolite is a porous hydrous aluminosilicate mineral with a unique pore structure, large specific surface area, and excellent adsorption, ion exchange, and catalytic properties. Numerous studies have confirmed that zeolite has a high adsorption efficiency for various VOCs. For example, Turan et al. found that natural zeolite can remove up to 79.73% of VOCs such as octane, acetic acid, and acetaldehyde from poultry litter (natural zeolite:poultry litter ratio = 1:10). Valdés et al. found that natural mordenite has a certain adsorption efficiency for benzene, toluene, and xylene, and that acid-treated natural mordenite significantly enhances its adsorption efficiency for these pollutants. Ling Yuanyou et al. from Guangdong Ward Environmental Protection New Materials Co., Ltd. prepared a natural zeolite air-purifying coating using natural zeolite, titanium dioxide, and attapulgite. Cui Tianshun et al. from Guangxi Normal University prepared a powdered environmentally friendly coating product using stilbene zeolite through washing, crushing, acid activation, and drying, effectively reducing the emission of harmful volatiles from the coating. On this basis, people have tried to add photocatalysts and / or antibacterial agents to zeolite paints to obtain zeolite paints with VOCs purification and antibacterial functions. For example, Li Junming et al. from Qingdao Jiayuan Oasis Paint Co., Ltd. mixed zeolite, zinc oxide, silver, copper, titanium dioxide, etc. to prepare a zeolite-based formaldehyde-purifying, antibacterial and mildew-proof paint; Xu Qinghua et al. prepared a zeolite colored paint powder with air purification function by using attapulgite clay powder, acidified zeolite particles, colored silicate cement, nano-silver-loaded antibacterial powder, nano-titanium dioxide, etc.; Wang Qing et al. from Shenyang Jianzhu University mixed zinc-loaded zeolite-based cerium-doped nano-titanium dioxide with styrene-acrylic emulsion, anatase-type titanium dioxide, talc powder, etc. to prepare a paint with antibacterial properties.

[0004] Although zeolite-based coatings have shown excellent environmental protection and broad application prospects, there are still two key issues to be studied and resolved in practical applications: On the one hand, most zeolite-based coatings currently on the market are made directly from natural zeolites or simply modified natural zeolites. The silicon-aluminum ratio of the zeolites used is mostly concentrated between 2-6, which belongs to medium-low silicon zeolites and has high hydrophilicity. Therefore, the developed zeolite-based coatings will preferentially adsorb water vapor in the air in practical applications, while the adsorption capacity of VOCs is not high. This problem is particularly prominent in high-humidity environments. On the other hand, currently, most of the zeolite coatings with photocatalytic and antibacterial / viral functions are obtained by directly adding photocatalysts and antibacterial agents to the zeolite coating. The added nanopowders are difficult to mix evenly with other components and are not evenly dispersed in the coating, thereby reducing its VOCs purification and antibacterial capabilities. Although this problem can be solved by immobilizing photocatalysts or antibacterial agents on the surface / pores of zeolite, the VOCs purification and antibacterial / viral efficacy of the obtained zeolite-based materials is still poor due to factors such as the limitations of zeolite structure and performance. Summary of the Invention

[0005] In view of the shortcomings of the existing technology, the purpose of the present invention is to provide a method for preparing a multifunctional zeolite-based environmentally friendly coating. The obtained zeolite-based environmentally friendly coating has excellent adsorption, visible light catalysis and antibacterial properties, can better adsorb and degrade VOCs, and has a good antibacterial effect.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] A method for preparing a multifunctional zeolite-based environmentally friendly coating comprises the following steps:

[0008] Step 1: Preparation of defect-rich high-silicon zeolite

[0009] Mix zeolite and an inorganic acid solution with a concentration of 4 to 8 mol / L in a ratio of (20 to 50 g): 1 L, react at 60 to 90°C for 12 to 24 hours, filter, wash with water, dry and grind in sequence to obtain defect-rich high-silica zeolite;

[0010] Step 2: Preparation of adsorption / visible light photocatalytic zeolite-based materials

[0011] First, defect-rich high-silicon zeolite, water, copper salt and titanium salt solution with a titanium ion concentration of 0.5-2 mol / L are respectively taken according to a mass ratio of 1: (25-40): (0.5-1): (3-5), and then the defect-rich high-silicon zeolite and water are mixed, and then the copper salt and titanium salt solutions are added, and the pH value is adjusted to be weakly alkaline, and the reaction is carried out at 50-80°C for 4-24 hours, and then aged, filtered, washed, dried and ground in sequence, and the product is collected and placed in a muffle furnace, and heated from room temperature to 400-800°C at a heating rate of 10°C / min, and calcined for 4-6 hours to obtain an adsorption / visible light photocatalytic zeolite-based material;

[0012] Step 3: Preparation of adsorption / visible light photocatalysis / antibacterial zeolite-based materials

[0013] According to the ratio of (20-30g): 1L, take an adsorption / visible light photocatalytic zeolite-based material and an antibacterial agent precursor solution with a silver ion concentration of 0.1-1 mol / L, exchange the silver ions with the adsorption / visible light photocatalytic zeolite-based material at 30-50°C for 2-12 hours, and reduce the silver ions to elemental silver by a reduction method to obtain an adsorption / visible light photocatalytic / antibacterial zeolite-based material;

[0014] Step 4: Preparation of multifunctional zeolite-based environmentally friendly coating

[0015] The rubber powder, the adsorption / visible light photocatalysis / antibacterial zeolite-based material and the inorganic filler are mixed and stirred uniformly according to a mass ratio of 1:(5-10):(10-20) to obtain a multifunctional zeolite-based environmentally friendly coating.

[0016] Furthermore, the zeolite in step 1 is a natural zeolite with a silicon-aluminum ratio of ≥4 or a synthetic ZSM-5 zeolite.

[0017] Furthermore, the inorganic acid solution in step 1 is nitric acid solution, sulfuric acid solution or hydrochloric acid solution.

[0018] Furthermore, the silicon-aluminum ratio of the defect-rich high-silicon zeolite obtained in step 1 is ≥21.

[0019] Furthermore, the copper salt in step 2 is copper nitrate, copper sulfate or copper chloride.

[0020] Furthermore, the titanium salt solution in step 2 is titanium tetrachloride solution, titanium sulfate solution, titanyl sulfate solution or tetrabutyl titanate solution.

[0021] Furthermore, the pH value of step 2 is 7 to 9.5.

[0022] Furthermore, the antibacterial agent precursor solution in step 3 is AgNO3 solution, AgCl solution or Ag2SO4 solution.

[0023] Furthermore, the reduction method in step 3 is to use sodium borohydride as a reducing agent to reduce silver ions to elemental silver, or to use ultraviolet light irradiation to reduce silver ions to elemental silver.

[0024] Furthermore, the inorganic filler in step 4 is calcium carbonate, kaolin, wollastonite, talc or white cement.

[0025] Compared with the prior art, the present invention has the following technical effects:

[0026] The present invention first deals with the zeolite through acid treatment and dealumination to obtain a defect-rich high-silica zeolite with a high specific surface area, hydrophobicity, and excellent adsorption performance. The defect-rich high-silica zeolite is then mixed with a copper salt and titanium salt solution and calcined to obtain a copper oxide / titanium oxide / zeolite-based material with excellent adsorption performance and visible light photocatalytic performance. The copper oxide / titanium oxide / zeolite-based material is then mixed with an antibacterial agent precursor solution containing silver ions, and the silver ions are converted into zero-valent elemental silver by a reduction method to obtain a silver / copper oxide / titanium oxide / zeolite-based material with excellent adsorption, visible light photocatalytic, and antibacterial performance. The silver / copper oxide / titanium oxide / zeolite-based material is then mixed with rubber powder and an inorganic filler in a proportion and stirred uniformly to obtain a zeolite-based environmentally friendly coating with excellent adsorption, visible light photocatalytic, and antibacterial functions. The coating can not only effectively adsorb and decompose organic pollutants in the air such as VOCs through photocatalytic oxidation, thus achieving a good air purification effect, but can also effectively kill most bacteria in the environment, thus having excellent environmental protection characteristics and extremely high promotion and application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 : XRD pattern of the adsorption / visible light photocatalytic / antibacterial zeolite prepared in Example 9 of the present invention;

[0028] Figure 2 : SEM photo and EDS spectrum of adsorption / visible light photocatalysis / antibacterial zeolite prepared in Example 9 of the present invention

[0029] Figure 3 : Bar graph of the adsorption performance of ZSM-5 zeolite and the adsorption / visible light photocatalytic / antibacterial zeolite prepared in Example 9 of the present invention for toluene and acetic acid;

[0030] Figure 4 : Photocatalytic performance curves of ZSM-5 zeolite, TiO2 and adsorption / visible light photocatalysis / antibacterial zeolite prepared in Example 9 of the present invention;

[0031] Figure 5 : Antibacterial performance effect diagram of the adsorption / visible light photocatalysis / antibacterial zeolite prepared in Example 9 of the present invention;

[0032] Figure 6: Rendering of the multifunctional zeolite-based environmentally friendly coating prepared in Example 9 of the present invention. DETAILED DESCRIPTION

[0033] The specific contents of the present invention are further explained in detail below with reference to the embodiments.

[0034] Example 1

[0035] Step 1: Preparation of defect-rich high-silicon zeolite

[0036] 30g of natural zeolite with a silicon-aluminum ratio of 4.3 was mixed with 1L of 4mol / L nitric acid solution, reacted at 70°C for 12h, filtered, washed with water until neutral, dried, and then ground to obtain defect-rich high-silicon zeolite with a silicon-aluminum ratio of 25;

[0037] Step 2: Preparation of adsorption / visible light photocatalytic zeolite-based materials

[0038] First, defect-rich high-silica zeolite, water, copper sulfate, and titanium sulfate solution with a titanium ion concentration of 0.5 mol / L were taken in a mass ratio of 1:25:0.5:3, and then the defect-rich high-silica zeolite and water were mixed. Then, copper sulfate and titanium sulfate solution were added, and the pH value was adjusted to 7. The reaction was carried out at 50°C for 12 hours, and then aged for 8 hours. Then, the reaction was filtered, washed with water to remove sulfate ions, and then dried and ground. The product was collected and placed in a muffle furnace. The temperature was increased from room temperature to 400°C at a heating rate of 10°C / min and calcined for 4 hours to obtain an adsorption / visible light photocatalytic zeolite-based material.

[0039] Step 3: Preparation of adsorption / visible light photocatalysis / antibacterial zeolite-based materials

[0040] 20g of adsorption / visible light photocatalytic zeolite-based material was mixed with 1L of AgNO3 solution with a silver ion concentration of 1mol / L. The silver ions were exchanged with the adsorption / visible light photocatalytic zeolite-based material at 50°C for 2h. The silver ions were then reduced to elemental silver under ultraviolet light irradiation to obtain an adsorption / visible light photocatalytic / antibacterial zeolite-based material with an antibacterial rate of 99%.

[0041] Step 4: Preparation of multifunctional zeolite-based environmentally friendly coating

[0042] The rubber powder, adsorption / visible light photocatalysis / antibacterial zeolite-based material and calcium carbonate are mixed and stirred evenly in a mass ratio of 1:5:10 to obtain a multifunctional zeolite-based environmentally friendly coating.

[0043] The degradation rate of methyl orange by the adsorption / visible light photocatalytic zeolite-based material prepared in Example 1 was 90%.

[0044] Example 2

[0045] Step 1: Preparation of defect-rich high-silicon zeolite

[0046] 50g of natural zeolite with a silicon-aluminum ratio of 4 was mixed with 1L of 6mol / L nitric acid solution, reacted at 60°C for 24h, filtered, washed with water until neutral, dried, and then ground to obtain defect-rich high-silicon zeolite with a silicon-aluminum ratio of 28;

[0047] Step 2: Preparation of adsorption / visible light photocatalytic zeolite-based materials

[0048] First, defect-rich high-silica zeolite, water, copper nitrate, and titanium sulfate solution with a titanium ion concentration of 1 mol / L were taken in a mass ratio of 1:30:0.6:5, and then the defect-rich high-silica zeolite and water were mixed. Then, copper nitrate and titanium sulfate solution were added, and the pH value was adjusted to 7.5. The reaction was carried out at 60°C for 8 hours, and then aged for 8 hours. Then, the reaction was filtered, and then washed with water to remove nitrate ions and sulfate ions. Then, the reaction was dried and ground. The product was collected and placed in a muffle furnace. The temperature was increased from room temperature to 600°C at a heating rate of 10°C / min, and calcined for 4 hours to obtain an adsorption / visible light photocatalytic zeolite-based material.

[0049] Step 3: Preparation of adsorption / visible light photocatalysis / antibacterial zeolite-based materials

[0050] 20g of adsorption / visible light photocatalytic zeolite-based material was mixed with 1L of AgNO3 solution with a silver ion concentration of 0.5mol / L. The silver ions were exchanged with the adsorption / visible light photocatalytic zeolite-based material at 30°C for 4h. The silver ions were then reduced to elemental silver under ultraviolet light irradiation to obtain an adsorption / visible light photocatalytic / antibacterial zeolite-based material with an antibacterial rate of 99%.

[0051] Step 4: Preparation of multifunctional zeolite-based environmentally friendly coating

[0052] The rubber powder, adsorption / visible light photocatalysis / antibacterial zeolite-based material and calcium carbonate are mixed and stirred evenly in a mass ratio of 1:8:15 to obtain a multifunctional zeolite-based environmentally friendly coating.

[0053] The degradation rate of methyl orange by the adsorption / visible light photocatalytic zeolite-based material prepared in Example 2 was 97%.

[0054] Example 3

[0055] Step 1: Preparation of defect-rich high-silicon zeolite

[0056] 40g of natural zeolite with a silicon-aluminum ratio of 5.2 was mixed with 1L of 8mol / L hydrochloric acid solution, reacted at 90°C for 12h, filtered, washed with water until neutral, dried, and then ground to obtain defect-rich high-silicon zeolite with a silicon-aluminum ratio of 35;

[0057] Step 2: Preparation of adsorption / visible light photocatalytic zeolite-based materials

[0058] First, defect-rich high-silica zeolite, water, copper nitrate, and titanium sulfate solution with a titanium ion concentration of 1.3 mol / L were taken in a mass ratio of 1:40:0.6:5, and then the defect-rich high-silica zeolite and water were mixed. Then, copper nitrate and titanium sulfate solution were added, and the pH value was adjusted to 9.5. The reaction was carried out at 50°C for 12 hours, and then aged for 12 hours. Then, the mixture was filtered, washed with water to remove nitrate ions and sulfate ions, and then dried and ground. The product was collected and placed in a muffle furnace. The temperature was increased from room temperature to 500°C at a heating rate of 10°C / min, and calcined for 5 hours to obtain an adsorption / visible light photocatalytic zeolite-based material.

[0059] Step 3: Preparation of adsorption / visible light photocatalysis / antibacterial zeolite-based materials

[0060] 25g of the adsorption / visible light photocatalytic zeolite-based material was mixed with 1L of a Ag2SO4 solution with a silver ion concentration of 0.6mol / L. The silver ions were exchanged with the adsorption / visible light photocatalytic zeolite-based material at 50°C for 4h. Then, sodium borohydride was used as a reducing agent to reduce the silver ions to elemental silver, resulting in an adsorption / visible light photocatalytic / antibacterial zeolite-based material with an antibacterial rate of 67%.

[0061] Step 4: Preparation of multifunctional zeolite-based environmentally friendly coating

[0062] The rubber powder, adsorption / visible light photocatalysis / antibacterial zeolite-based material and kaolin are mixed and stirred evenly in a mass ratio of 1:6:20 to obtain a multifunctional zeolite-based environmentally friendly coating.

[0063] The degradation rate of methyl orange by the adsorption / visible light photocatalytic zeolite-based material prepared in Example 3 was 87%.

[0064] Example 4

[0065] Step 1: Preparation of defect-rich high-silicon zeolite

[0066] 35g of natural zeolite with a silicon-aluminum ratio of 4.7 was mixed with 1L of 5mol / L hydrochloric acid solution, reacted at 60°C for 15h, filtered, washed with water until neutral, dried, and then ground to obtain defect-rich high-silicon zeolite with a silicon-aluminum ratio of 21;

[0067] Step 2: Preparation of adsorption / visible light photocatalytic zeolite-based materials

[0068] First, defect-rich high-silica zeolite, water, copper chloride, and titanium tetrachloride solution with a titanium ion concentration of 2 mol / L were taken in a mass ratio of 1:35:0.7:3, and then the defect-rich high-silica zeolite and water were mixed. Then, copper chloride and titanium tetrachloride solution were added, and the pH value was adjusted to 8. The reaction was carried out at 60°C for 15 hours, and then aged for 24 hours. Then, the mixture was filtered, washed with water until neutral, and then dried and ground. The product was collected and placed in a muffle furnace. The temperature was increased from room temperature to 650°C at a heating rate of 10°C / min, and calcined for 5 hours to obtain an adsorption / visible light photocatalytic zeolite-based material.

[0069] Step 3: Preparation of adsorption / visible light photocatalysis / antibacterial zeolite-based materials

[0070] 30g of the adsorption / visible light photocatalytic zeolite-based material was mixed with 1L of a 0.2mol / L silver ion Ag2SO4 solution. The silver ions were exchanged with the adsorption / visible light photocatalytic zeolite-based material at 45°C for 6h. Then, sodium borohydride was used as a reducing agent to reduce the silver ions to elemental silver, resulting in an adsorption / visible light photocatalytic / antibacterial zeolite-based material with an antibacterial rate of 89%.

[0071] Step 4: Preparation of multifunctional zeolite-based environmentally friendly coating

[0072] The rubber powder, adsorption / visible light photocatalysis / antibacterial zeolite-based material and kaolin are mixed and stirred uniformly in a mass ratio of 1:10:12 to obtain a multifunctional zeolite-based environmentally friendly coating.

[0073] The degradation rate of methyl orange of the adsorption / visible light photocatalytic zeolite-based material prepared in Example 4 was 99%.

[0074] Example 5

[0075] Step 1: Preparation of defect-rich high-silicon zeolite

[0076] 20g of natural zeolite with a silicon-aluminum ratio of 4.1 was mixed with 1L of 6mol / L sulfuric acid solution, reacted at 60°C for 24h, filtered, washed with water until neutral, dried, and then ground to obtain defect-rich high-silicon zeolite with a silicon-aluminum ratio of 25;

[0077] Step 2: Preparation of adsorption / visible light photocatalytic zeolite-based materials

[0078] First, defect-rich high-silica zeolite, water, copper chloride, and titanium sulfate solution with a titanium ion concentration of 2 mol / L were taken in a mass ratio of 1:32.5:0.9:5, and then the defect-rich high-silica zeolite and water were mixed. Then, copper chloride and titanium sulfate solution were added, and the pH value was adjusted to 7. The reaction was carried out at 60°C for 24 hours, and then aged for 24 hours. Then, the mixture was filtered, washed with water to remove residual sulfate ions, and then dried and ground. The product was collected and placed in a muffle furnace. The temperature was increased from room temperature to 800°C at a heating rate of 10°C / min, and calcined for 6 hours to obtain an adsorption / visible light photocatalytic zeolite-based material.

[0079] Step 3: Preparation of adsorption / visible light photocatalysis / antibacterial zeolite-based materials

[0080] 30g of the adsorption / visible light photocatalytic zeolite-based material was mixed with 1L of an AgCl solution with a silver ion concentration of 0.1mol / L. The silver ions were exchanged with the adsorption / visible light photocatalytic zeolite-based material at 50°C for 12h. Then, sodium borohydride was used as a reducing agent to reduce the silver ions to elemental silver, resulting in an adsorption / visible light photocatalytic / antibacterial zeolite-based material with an antibacterial rate of 56%.

[0081] Step 4: Preparation of multifunctional zeolite-based environmentally friendly coating

[0082] The rubber powder, adsorption / visible light photocatalysis / antibacterial zeolite-based material and wollastonite are mixed and stirred uniformly in a mass ratio of 1:5:20 to obtain a multifunctional zeolite-based environmentally friendly coating.

[0083] The degradation rate of methyl orange of the adsorption / visible light photocatalytic zeolite-based material prepared in Example 5 was 97%.

[0084] Example 6

[0085] Step 1: Preparation of defect-rich high-silicon zeolite

[0086] 25g of ZSM-5 zeolite with a silicon-aluminum ratio of 21 was mixed with 1L of 8mol / L nitric acid solution, reacted at 70°C for 18h, filtered, washed with water until neutral, dried, and then ground to obtain a defect-rich high-silica zeolite with a silicon-aluminum ratio of 42.

[0087] Step 2: Preparation of adsorption / visible light photocatalytic zeolite-based materials

[0088] First, defect-rich high-silica zeolite, water, copper sulfate, and titanium sulfate solution with a titanium ion concentration of 1 mol / L were taken in a mass ratio of 1:25:0.8:4, then the defect-rich high-silica zeolite and water were mixed, and then copper sulfate and titanium sulfate solution were added, and the pH value was adjusted to 9.5. The reaction was carried out at 70°C for 20 hours, and then aged for 8 hours. Then, the reaction was filtered, and then washed with water to remove sulfate ions. The product was then dried and ground. The collected product was placed in a muffle furnace, heated from room temperature to 800°C at a heating rate of 10°C / min, and calcined for 4 hours to obtain an adsorption / visible light photocatalytic zeolite-based material.

[0089] Step 3: Preparation of adsorption / visible light photocatalysis / antibacterial zeolite-based materials

[0090] 25g of adsorption / visible light photocatalytic zeolite-based material was mixed with 1L of AgNO3 solution with a silver ion concentration of 0.3mol / L. The silver ions were exchanged with the adsorption / visible light photocatalytic zeolite-based material at 40°C for 8h. The silver ions were then reduced to elemental silver under ultraviolet light irradiation to obtain an adsorption / visible light photocatalytic / antibacterial zeolite-based material with an antibacterial rate of 99%.

[0091] Step 4: Preparation of multifunctional zeolite-based environmentally friendly coating

[0092] The rubber powder, adsorption / visible light photocatalysis / antibacterial zeolite-based material and wollastonite are mixed and stirred evenly in a mass ratio of 1:7:10 to obtain a multifunctional zeolite-based environmentally friendly coating.

[0093] The degradation rate of methyl orange by the adsorption / visible light photocatalytic zeolite-based material prepared in Example 6 was 89%.

[0094] Example 7

[0095] Step 1: Preparation of defect-rich high-silicon zeolite

[0096] 45 g of ZSM-5 zeolite with a silicon-aluminum ratio of 24 was mixed with 1 L of 5 mol / L hydrochloric acid solution, reacted at 70°C for 20 h, filtered, washed with water until neutral, dried, and then ground to obtain a defect-rich high-silicon zeolite with a silicon-aluminum ratio of 43.

[0097] Step 2: Preparation of adsorption / visible light photocatalytic zeolite-based materials

[0098] First, defect-rich high-silica zeolite, water, copper nitrate, and titanium tetrachloride solution with a titanium ion concentration of 2 mol / L were taken in a mass ratio of 1:25:0.8:3, and then the defect-rich high-silica zeolite and water were mixed. Then, copper nitrate and titanium tetrachloride solution were added, and the pH value was adjusted to 7. The reaction was carried out at 70°C for 24 hours, and then aged for 24 hours. Then, the reaction was filtered, and then washed with water to remove nitrate ions. The reaction was then dried and ground. The product was collected and placed in a muffle furnace. The temperature was increased from room temperature to 400°C at a heating rate of 10°C / min, and calcined for 4 hours to obtain an adsorption / visible light photocatalytic zeolite-based material.

[0099] Step 3: Preparation of adsorption / visible light photocatalysis / antibacterial zeolite-based materials

[0100] 25g of adsorption / visible light photocatalytic zeolite-based material was mixed with 1L of AgNO3 solution with a silver ion concentration of 0.2mol / L. The silver ions were exchanged with the adsorption / visible light photocatalytic zeolite-based material at 30°C for 10h. The silver ions were then reduced to elemental silver under ultraviolet light irradiation to obtain an adsorption / visible light photocatalytic / antibacterial zeolite-based material with an antibacterial rate of 99%.

[0101] Step 4: Preparation of multifunctional zeolite-based environmentally friendly coating

[0102] The rubber powder, adsorption / visible light photocatalysis / antibacterial zeolite-based material and talcum powder are mixed and stirred evenly in a mass ratio of 1:9:20 to obtain a multifunctional zeolite-based environmentally friendly coating.

[0103] The degradation rate of methyl orange by the adsorption / visible light photocatalytic zeolite-based material prepared in Example 7 was 89%.

[0104] Example 8

[0105] Step 1: Preparation of defect-rich high-silicon zeolite

[0106] 50g of ZSM-5 zeolite with a silicon-aluminum ratio of 22 was mixed with 1L of 7mol / L sulfuric acid solution, reacted at 80°C for 24h, filtered, washed with water until neutral, dried, and then ground to obtain defect-rich high-silicon zeolite with a silicon-aluminum ratio of 64.

[0107] Step 2: Preparation of adsorption / visible light photocatalytic zeolite-based materials

[0108] First, defect-rich high-silica zeolite, water, copper chloride, and tetrabutyl titanate solution with a titanium ion concentration of 1.7 mol / L were taken in a mass ratio of 1:30:1:4, then the defect-rich high-silica zeolite and water were mixed, and then copper chloride and tetrabutyl titanate solution were added, and the pH value was adjusted to 8.5. The reaction was carried out at 80°C for 24 hours, and then aged for 8 hours. Then, the reaction was filtered, washed with water until neutral, and then dried and ground. The product was collected and placed in a muffle furnace, heated from room temperature to 700°C at a heating rate of 10°C / min, and calcined for 6 hours to obtain an adsorption / visible light photocatalytic zeolite-based material;

[0109] Step 3: Preparation of adsorption / visible light photocatalysis / antibacterial zeolite-based materials

[0110] 25 g of the adsorption / visible light photocatalytic zeolite-based material was mixed with 1 L of an AgCl solution having a silver ion concentration of 0.4 mol / L. The silver ions were exchanged with the adsorption / visible light photocatalytic zeolite-based material at 40°C for 9 h. Sodium borohydride was used as a reducing agent to reduce the silver ions to elemental silver, thereby obtaining an adsorption / visible light photocatalytic / antibacterial zeolite-based material with an antibacterial rate of 97%.

[0111] Step 4: Preparation of multifunctional zeolite-based environmentally friendly coating

[0112] The rubber powder, the adsorption / visible light photocatalysis / antibacterial zeolite-based material and the talcum powder are mixed and stirred evenly in a mass ratio of 1:5:18 to obtain a multifunctional zeolite-based environmentally friendly coating.

[0113] The degradation rate of methyl orange by the adsorption / visible light photocatalytic zeolite-based material prepared in Example 8 was 93%.

[0114] Example 9

[0115] Step 1: Preparation of defect-rich high-silicon zeolite

[0116] 35g of ZSM-5 zeolite with a silicon-aluminum ratio of 21 was mixed with 1L of 8mol / L nitric acid solution, reacted at 70°C for 24h, filtered, washed with water until neutral, dried, and then ground to obtain a defect-rich high-silicon zeolite with a silicon-aluminum ratio of 75.

[0117] Step 2: Preparation of adsorption / visible light photocatalytic zeolite-based materials

[0118] First, defect-rich high-silica zeolite, water, copper nitrate, and titanium sulfate solution with a titanium ion concentration of 2 mol / L were taken in a mass ratio of 1:30:0.8:3, and then the defect-rich high-silica zeolite and water were mixed. Then, copper nitrate and titanium sulfate solution were added, and the pH value was adjusted to 7. The reaction was carried out at 80°C for 4 hours, and then aged for 24 hours. Then, the reaction was filtered, and then washed with water to remove nitrate ions and sulfate ions. Then, the reaction was dried and ground. The product was collected and placed in a muffle furnace. The temperature was increased from room temperature to 650°C at a heating rate of 10°C / min, and calcined for 4 hours to obtain an adsorption / visible light photocatalytic zeolite-based material.

[0119] Step 3: Preparation of adsorption / visible light photocatalysis / antibacterial zeolite-based materials

[0120] 25g of adsorption / visible light photocatalytic zeolite-based material was mixed with 1L of AgNO3 solution with a silver ion concentration of 0.1mol / L. The silver ions were exchanged with the adsorption / visible light photocatalytic zeolite-based material at 30°C for 2h. The silver ions were then reduced to elemental silver under ultraviolet light irradiation to obtain an adsorption / visible light photocatalytic / antibacterial zeolite-based material with an antibacterial rate of 99%.

[0121] Step 4: Preparation of multifunctional zeolite-based environmentally friendly coating

[0122] The rubber powder, adsorption / visible light photocatalysis / antibacterial zeolite-based material and white cement are mixed and stirred evenly in a mass ratio of 1:10:15 to obtain a multifunctional zeolite-based environmentally friendly coating.

[0123] The degradation rate of methyl orange of the adsorption / visible light photocatalytic zeolite-based material prepared in Example 9 was 90%.

[0124] See also Figure 1 Through XRD analysis, it can be seen that titanium dioxide in the synthesized adsorption / visible light photocatalytic / antibacterial zeolite phase is successfully immobilized on the zeolite surface. Due to the low content of copper oxide and silver elements in the sample, they are not shown in the XRD diagram.

[0125] See also Figure 2 , it can be seen from the SEM-EDS analysis that the sample contains Ti, Cu and Ag elements, indicating that titanium dioxide, copper oxide and silver elements exist in the sample.

[0126] See also Figure 3 It can be seen that the adsorption / visible light photocatalytic / antibacterial zeolite synthesized in Example 9 has a better adsorption effect on toluene and ethyl acetate than the original zeolite ZSM-5, indicating that it has excellent adsorption performance for volatile organic compounds (VOCs).

[0127] See also Figure 4It can be seen that the adsorption / visible light photocatalytic / antibacterial zeolite synthesized in Example 9 has a degradation rate of 90% for methyl orange under xenon lamp irradiation. Under the same conditions, the degradation rate of methyl orange by TiO2 is only 64%. The original zeolite ZSM-5 has only an adsorption effect on methyl orange and has no degradation effect.

[0128] See also Figure 5 It can be seen that in the control group, a relatively dense population of Staphylococcus aureus floated on the surface of the coating prepared by the original zeolite ZSM-5, while almost no Staphylococcus aureus was seen on the surface of the multifunctional zeolite-based environmentally friendly coating prepared in the present application. It can be seen that the multifunctional zeolite-based environmentally friendly coating prepared in Example 9 can kill Staphylococcus aureus on a large scale and has excellent antibacterial properties.

[0129] See also Figure 6 It can be seen that the prepared multifunctional zeolite-based environmentally friendly coating can be evenly coated on the surface of the object.

Claims

1. A method for preparing a multifunctional zeolite-based environmentally friendly coating, characterized in that: The steps include: Step 1: Preparation of defect-rich high-silicon zeolite Zeolite and an inorganic acid solution with a concentration of 4-8 mol / L were mixed in a ratio of (20-50 g): 1 L, and the mixture was reacted at 60-90°C for 12-24 hours. The mixture was then filtered, washed with water, dried, and ground to obtain defect-rich high-silica zeolite with a silicon-aluminum ratio of ≥21. Step 2: Preparation of adsorption / visible light photocatalytic zeolite-based materials First, defect-rich high-silica zeolite, water, copper salt, and titanium salt solution with a titanium ion concentration of 0.5-2 mol / L are respectively taken according to a mass ratio of 1: (25-40): (0.5-1): (3-5), then the defect-rich high-silica zeolite and water are mixed, and then the copper salt and titanium salt solutions are added, and the pH value is adjusted to be weakly alkaline. The reaction is carried out at 50-80°C for 4-24 hours, and then the reaction is carried out in sequence, filtered, washed with water, dried and ground. The product is collected and placed in a muffle furnace, heated from room temperature to 400-800°C at a heating rate of 10°C / min, and calcined for 4-6 hours to obtain an adsorption / visible light photocatalytic zeolite-based material; Step 3: Preparation of adsorption / visible light photocatalysis / antibacterial zeolite-based materials According to the ratio of (20-30 g): 1 L, the adsorption / visible light photocatalytic zeolite-based material and the antibacterial agent precursor solution with a silver ion concentration of 0.1-1 mol / L were mixed, and the silver ions were exchanged with the adsorption / visible light photocatalytic zeolite-based material at 30-50°C for 2-12 hours. The silver ions were reduced to elemental silver by a reduction method to obtain the adsorption / visible light photocatalytic / antibacterial zeolite-based material; Step 4: Preparation of multifunctional zeolite-based environmentally friendly coating The rubber powder, the adsorption / visible light photocatalytic / antibacterial zeolite-based material and the inorganic filler are mixed and stirred uniformly in a mass ratio of 1: (5-10): (10-20) to obtain a multifunctional zeolite-based environmentally friendly coating.

2. The method for preparing the multifunctional zeolite-based environmentally friendly coating according to claim 1, characterized in that: The inorganic acid solution in step 1 is nitric acid solution, sulfuric acid solution or hydrochloric acid solution.

3. The method for preparing the multifunctional zeolite-based environmentally friendly coating according to claim 1, characterized in that: The copper salt in step 2 is copper nitrate, copper sulfate or copper chloride.

4. The method for preparing the multifunctional zeolite-based environmentally friendly coating according to claim 1, characterized in that: The titanium salt solution in step 2 is titanium tetrachloride solution, titanium sulfate solution or titanyl sulfate solution.

5. The method for preparing the multifunctional zeolite-based environmentally friendly coating according to claim 1, characterized in that: The pH value of step 2 is 7-9.

5.

6. The method for preparing the multifunctional zeolite-based environmentally friendly coating according to claim 1, characterized in that: The antibacterial agent precursor solution in step 3 is AgNO3 solution.

7. The method for preparing the multifunctional zeolite-based environmentally friendly coating according to claim 1, characterized in that: The reduction method in step 3 is to use sodium borohydride as a reducing agent to reduce silver ions to silver element, or to use ultraviolet light irradiation to reduce silver ions to silver element.

8. The method for preparing the multifunctional zeolite-based environmentally friendly coating according to claim 1, characterized in that: The inorganic filler in step 4 is calcium carbonate, kaolin, wollastonite, talc or white cement.

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