Formaldehyde-eliminating rare earth coating metal plate and preparation method thereof
Through photocatalytic technology of rare earth elements doping WO3/sepiolite composite materials, a rare earth coating metal plate was prepared to dissolve formaldehyde, which solved the problem of removing formaldehyde in newly decorated rooms, and achieved efficient formaldehyde degradation and improvement of indoor air quality.
Patent Information
- Application Number
- CN202411653027.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-19
- Publication Date
- 2025-05-06
AI Technical Summary
The existing technology is difficult to effectively remove the high concentration of formaldehyde in newly decorated rooms, resulting in poor indoor air quality and affecting health.
Rare earth elements doped with WO3/sepiolite composite material, and photocatalytic degradation of formaldehyde was prepared to digest formaldehyde rare earth coating metal plate. The method includes the preparation of rare earth composite powder, the preparation of rare earth element-doped WO3/sepiolite composite material, and the curing process of rare earth coatings.
It has achieved efficient degradation of formaldehyde, with the highest degradation rate of up to 94.8%, effectively improving indoor air quality and suitable for interior decoration and formaldehyde removal.
Smart Images
Figure CN119931428A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of environmentally friendly building materials, and in particular to a method for preparing a rare earth coated metal plate capable of degrading formaldehyde. Background Art
[0002] Formaldehyde is a substance released by the decomposition of sodium formaldehyde bisulfite at above 60°C. It is colorless, has a pungent odor, and is easily soluble in water. The main hazard of formaldehyde is the irritation to the skin and mucous membranes. When formaldehyde reaches a certain concentration indoors, people will feel uncomfortable. 3 The formaldehyde concentration can cause red eyes, itchy eyes, throat discomfort or pain, hoarseness, sneezing, chest tightness, asthma, dermatitis, etc. The formaldehyde content in newly renovated rooms is high, which is the main cause of many diseases.
[0003] The methods of removing formaldehyde are generally divided into adsorption and catalysis. Activated carbon is often used for adsorption, while titanium dioxide is the most common catalysis method. Summary of the invention
[0004] The technical problem to be solved by the present invention is to provide a method for preparing a rare earth coated metal plate for degrading formaldehyde, so as to solve the technical problems in the above-mentioned background technology.
[0005] The technical solution of the present invention is:
[0006] A method for preparing a rare earth coated metal plate for degrading formaldehyde comprises the following steps:
[0007] (1) Preparation of rare earth composite powder: Eu and Gd oxides are dissolved in nitric acid solution. After the reaction is complete, rare earth nitrate is prepared. It is then mixed with ethanol aqueous solution at a volume ratio of 1:1. An appropriate amount of nano WO3 powder is added. After grinding for 40-60 minutes, the precursor is slowly dried under an infrared lamp to obtain a precursor. The precursor is then calcined at 580°C-640°C for 4-5 hours to obtain a rare earth composite powder.
[0008] (2) Preparation of rare earth element doped WO3 / sepiolite composite materials: rare earth composite materials and sepiolite were mixed in a ratio of 10:1-5, and then anhydrous ethanol was added and ground for 60-80 min. Then, the mixture was heated in a muffle furnace at a constant temperature of 320°C for 6-8 h, and slowly cooled to room temperature. After cooling, the sample was taken out and ground to a uniform fineness to obtain a rare earth element doped WO3 / sepiolite composite material.
[0009] (3) Preparation of formaldehyde-degrading rare earth coating: Add 3-7 wt % of rare earth element-doped WO3 / sepiolite composite material to fluorocarbon varnish, mix well and grind until the particle size of the rare earth element-doped WO3 / sepiolite composite material is 2-4 μm, filter to obtain the ground liquid, and thus obtain the rare earth coating.
[0010] (4) Curing of rare earth coating: After the formaldehyde-dissolving rare earth coating is rolled on one side of the metal base plate, it is baked in an oven at a temperature of 250-300° C. for 100-200 seconds to cure the rare earth coating, thereby obtaining a formaldehyde-dissolving rare earth coated metal plate.
[0011] Furthermore, in step 1, the concentration of ethanol is 30-50wt%, and the mass ratio of rare earth oxide to WO3 powder is 1:5-8.
[0012] Furthermore, before carrying out step 4, a primer layer and a topcoat layer are sequentially coated on one side of the metal plate, and each layer is sequentially baked and cured according to the existing process. After curing, a formaldehyde-degrading rare earth coating is roller-coated on the surface of the topcoat layer.
[0013] Furthermore, before the primer layer is applied, a trivalent chromium passivating agent is roller-coated on both sides of the metal plate, and then heated and cured in a drying oven to form a coating.
[0014] Furthermore, the metal bottom plate is made of stainless steel plate, aluminum plate or magnesium plate.
[0015] Furthermore, the stainless steel plate is selected from one of cold-rolled plate, hot-dip galvanized steel plate, electro-galvanized steel plate or galvanized steel plate.
[0016] Furthermore, the magnesium plate is a galvanized aluminum-magnesium plate or an aluminum-magnesium alloy plate.
[0017] The present invention also provides a rare earth coated metal plate for degrading formaldehyde, which is prepared by the above method.
[0018] The present invention is beneficial in that:
[0019] The present invention is doped with rare earth element ions (Eu 3+ and Gd 3+ )Solve WO 3 Due to the defects of easy photocorrosion and low visible light utilization, the WO3 light absorption frequency range can be expanded and the absorption intensity in the visible light region can be increased, thereby obtaining a higher visible light utilization rate and photocatalytic degradation efficiency of formaldehyde. Then, sepiolite is used as a carrier to prepare rare earth element-doped WO3 / sepiolite composite materials by sintering method to solve the agglomeration problem. Finally, it is prepared into formaldehyde-degrading rare earth coating and solidified on the metal base plate. The formaldehyde removal rate of this formaldehyde-degrading rare earth coated metal plate can reach up to 94.8%, which can be used for interior decoration to remove indoor formaldehyde. DETAILED DESCRIPTION
[0020] The specific embodiments of the present invention are further described below. It should be noted that the description of these embodiments is used to help understand the present invention, but does not constitute a limitation of the present invention. In addition, the technical features involved in each embodiment of the present invention described below can be combined with each other as long as they do not conflict with each other.
[0021] A method for preparing a rare earth coated metal plate for degrading formaldehyde, the steps are as follows:
[0022] First, prepare the rare earth composite powder:
[0023] As a photocatalyst, yellow WO3 has significant volume effect, surface effect, quantum size effect and macroscopic quantum tunneling effect. Compared with commonly used photocatalysts such as TiO2 and ZnO, yellow tungsten oxide has a smaller bandgap width and a larger light absorption range, and can more effectively utilize visible light, which accounts for nearly half of the solar radiation energy. Moreover, WO3 has a simple preparation process, a small bandgap energy (about 2.5eV), can absorb visible light with a wavelength less than 480nm, and has potential photocatalytic ability.
[0024] However, WO3 is difficult to obtain stable photocatalytic performance due to its defects such as easy photocorrosion and low visible light utilization rate. Therefore, the present invention can expand the light absorption frequency range of WO3 by doping rare earth elements, increase the absorption intensity in the visible light region, thereby obtaining a higher visible light utilization rate and photocatalytic degradation efficiency of formaldehyde. Rare earth elements have a larger ion radius than W elements and are difficult to enter the WO3 lattice. They mainly exist on the surface of WO3 microcrystals or dispersed in the gaps between WO3 microcrystals. They have f electrons and a strong adsorption effect, thereby improving the efficiency of photocatalytic reaction.
[0025] Firstly, the oxides of Eu and Gd are dissolved in a nitric acid solution, and rare earth nitrate is prepared after the reaction is complete, and then mixed with an ethanol aqueous solution with a concentration of 30-50wt% in a volume ratio of 1:1, and an appropriate amount of nano WO3 powder is added, and the mass ratio of rare earth oxide to WO3 powder is 1:5-8; after grinding for 40-60 minutes, the precursor is slowly dried under an infrared lamp to obtain a precursor, and then the precursor is roasted at 580°C-640°C for 4-5 hours to obtain a rare earth composite powder;
[0026] Next is the preparation of rare earth element doped WO3 / sepiolite composite materials
[0027] Rare earth composite powders are doped with rare earth ions in nano WO3 powders, and the particle size is extremely small, so they are easy to agglomerate, resulting in a reduced surface contact rate with the degradation products, which affects the photocatalytic degradation effect of formaldehyde. As a magnesium-rich chain silicate mineral with a unique nanostructure pore size, sepiolite has a crystal structure of chain and layer transition type, and the small units containing layered structure type in the chain structure belong to the 2:1 type. Due to this special structure, sepiolite has a large porosity and specific surface area, and can adsorb a variety of simple substances or compounds.
[0028] The present invention combines the rare earth composite material and sepiolite by a sintering method. After the rare earth composite material and sepiolite are mixed in a ratio of 10:1-5, anhydrous ethanol is added and ground for 60-80 minutes, and then heated at a constant temperature of 320°C for 6-8 hours in a muffle furnace, and slowly cooled to room temperature; after cooling, the sample is taken out and ground to uniform fineness, so as to obtain a rare earth element doped WO3 / sepiolite composite material. The material comprehensively utilizes the adsorption performance of sepiolite and the photocatalytic performance of the rare earth composite powder, and the two complement each other, and can effectively improve its photocatalytic activity.
[0029] The samples were characterized by SEM, XRD, FT-IR, UV-Vis and other experimental techniques, and the morphology, structure, composition and photocatalytic degradation performance of the composite material were analyzed. 3+ and Gd 3+ The photocatalytic effect of the composite material can reach up to 94.8%.
[0030] Preparation of rare earth coatings for formaldehyde digestion
[0031] The rare earth element doped WO3 / sepiolite composite material is added to the fluorocarbon varnish at a ratio of 3-7wt%, mixed evenly and ground until the particle size of the rare earth element doped WO3 / sepiolite composite material is 2-4μm, filtered to obtain the ground liquid, thereby obtaining a rare earth coating.
[0032] After the rare earth coating is prepared, the formaldehyde-dissolving rare earth coating is rolled on one side of the metal base plate, and then baked in an oven at a temperature of 250-300° C. for 100-200 seconds to solidify the rare earth coating, thereby obtaining a formaldehyde-dissolving rare earth coated metal plate.
[0033] As an improved solution, before applying the rare earth coating, trivalent chromium passivator can be roller-coated on both sides of the metal plate, and then heated and cured in a drying oven to form a chemical coating. Then, a primer layer and a topcoat layer are sequentially applied to one side of the metal plate, and each layer is baked and cured in turn according to the existing process. After curing, a formaldehyde-degrading rare earth coating is roller-coated on the surface of the topcoat layer.
[0034] The present invention also provides a rare earth coated metal plate for degrading formaldehyde, which is prepared by the above method.
[0035] The above metal base plates can be made of stainless steel plates, aluminum plates or magnesium plates according to customer requirements or usage requirements; the stainless steel plates are selected from one of cold-rolled plates, hot-dip galvanized steel plates, electro-galvanized steel plates or aluminum-zinc-coated steel plates; the magnesium plates can be galvanized aluminum-magnesium plates or aluminum-magnesium alloy plates.
[0036] The embodiments of the present invention are described in detail above, but the present invention is not limited to the described embodiments. For those skilled in the art, various changes, modifications, substitutions and variations of these embodiments are made without departing from the principles and spirit of the present invention, and still fall within the protection scope of the present invention.
Claims
1. A method for preparing a rare earth coated metal plate for eliminating formaldehyde, characterized in that: The following steps are involved: (1) Preparation of rare earth composite powder: Eu and Gd oxides are dissolved in nitric acid solution. After the reaction is complete, rare earth nitrate is prepared. Then, it is mixed with ethanol aqueous solution at a volume ratio of 1:1, and an appropriate amount of nano WO3 powder is added. After grinding for 40-60 minutes, it is slowly dried under an infrared lamp to obtain a precursor. Then, the precursor is calcined at 580℃-640℃ for 4-5 hours. Obtaining rare earth composite powder; (2) Preparation of rare earth element doped WO3 / sepiolite composite material: rare earth composite material and sepiolite were mixed in a ratio of 10:1-5, and then anhydrous ethanol was added and ground for 60-80 minutes, and then heated at a constant temperature of 320°C in a muffle furnace for 6-8 hours, and slowly cooled to room temperature; after cooling, the sample was taken out and ground to uniform fineness, thereby obtaining a rare earth element doped WO3 / sepiolite composite material; (3) Preparation of formaldehyde-eliminating rare earth coating: adding 3-7 wt % of rare earth element-doped WO3 / sepiolite composite material to fluorocarbon varnish, mixing evenly and grinding until the particle size of the rare earth element-doped WO3 / sepiolite composite material is 2-4 μm, filtering to obtain the ground liquid, thereby obtaining rare earth coating; (4) Curing of rare earth coating: After the formaldehyde-dissolving rare earth coating is rolled on one side of the metal base plate, it is baked in an oven at a temperature of 250-300° C. for 100-200 seconds to cure the rare earth coating, thereby obtaining a formaldehyde-dissolving rare earth coated metal plate.
2. The method for preparing a rare earth coated metal plate for eliminating formaldehyde according to claim 1, characterized in that: In step 1, the concentration of ethanol is 30-50wt%, and the mass ratio of rare earth oxide to WO3 powder is 1:5-8.
3. The method for preparing a rare earth coated metal plate for eliminating formaldehyde according to claim 1 or 2, characterized in that: Before step 4, a primer layer and a topcoat layer are sequentially coated on one side of the metal plate, and each layer is sequentially baked and cured according to the existing process. After curing, a formaldehyde-degrading rare earth coating is roller-coated on the surface of the topcoat layer.
4. The method for preparing a rare earth coated metal plate for eliminating formaldehyde according to claim 3, characterized in that: Before the primer layer is applied, trivalent chromium passivator is rolled on both sides of the metal plate, and then heated and cured in a drying oven to form a chemical coating.
5. The method for preparing a rare earth coated metal plate for eliminating formaldehyde according to claim 3, characterized in that: The metal bottom plate is selected from stainless steel plate, aluminum plate or magnesium plate.
6. The method for preparing a rare earth coated metal plate for eliminating formaldehyde according to claim 3, characterized in that: The stainless steel plate is selected from one of a cold-rolled plate, a hot-dip galvanized steel plate, an electro-galvanized steel plate or an galvanized steel plate.
7. The method for preparing a rare earth coated metal plate for eliminating formaldehyde according to claim 3, characterized in that: The magnesium plate is a galvanized aluminum-magnesium plate or an aluminum-magnesium alloy plate.
8. A rare earth coated metal plate for degrading formaldehyde, characterized in that: The metal plate is prepared by the method for manufacturing a rare earth coated metal plate for degrading formaldehyde as described in any one of claims 1 to 7.