CN-122011805-A - High-performance bismuth vanadate pigment coated with multi-metal oxide in situ and preparation method thereof

CN122011805ACN 122011805 ACN122011805 ACN 122011805ACN-122011805-A

Abstract

The invention relates to the technical field of inorganic pigment preparation, in particular to a high-performance bismuth vanadate pigment coated with multi-metal oxide in situ and a preparation method thereof. The preparation method comprises the steps of preparing a precursor, preparing a bismuth-containing solution A and a vanadium-containing solution B with the concentration of 0.1-2.0 mol/L respectively, preparing a coating agent solution with the total concentration of 0.5-2.0 mol/L, carrying out in-situ deposition coating, mixing the bismuth-containing solution A and the vanadium-containing solution B to obtain a mixed solution C, adding the coating agent solution, controlling the total metal ion content of the coating solution to be 5% -20% of the total content of vanadium and bismuth, regulating the pH value to be 5-8, reacting to obtain the bismuth vanadate precursor, and carrying out post-treatment. According to the invention, the metal oxide layer is coated in situ in the preparation process of BiVO 4 , so that the composition and structure of the coating layer are accurately regulated, the excellent color performance of the pigment is ensured, and meanwhile, the acid-base resistance, weather resistance and other performances of the pigment are obviously improved.

Inventors

LI JIE
LI WENJING
YANG YADONG
ZENG HUA

Assignees

成都先进金属材料产业技术研究院股份有限公司

Dates

Publication Date: 20260512
Application Date: 20260227

Claims (10)

1. The preparation method of the high-performance bismuth vanadate pigment coated with the multi-metal oxide in situ is characterized by comprising the following steps of: preparing a precursor, namely respectively preparing a bismuth-containing solution A and a vanadium-containing solution B with the concentration of 0.1-2.0 mol/L, wherein the concentration of the bismuth-containing solution A is consistent with that of the vanadium-containing solution B; Preparing a coating agent solution, namely preparing the coating agent solution with the total concentration of 0.5-2.0 mol/L; Mixing the bismuth-containing solution A and the vanadium-containing solution B at normal temperature for reaction for 30-90 minutes to obtain a mixed solution C, adding the coating agent solution into the mixed solution C, controlling the total metal ion content of the coating solution to be 5-20% of the total content of vanadium and bismuth, adjusting the pH value to 5-8, reacting for 30-90 minutes, filtering, washing and drying to obtain a bismuth vanadate precursor; And (3) post-treatment, namely calcining the bismuth vanadate precursor for 1-6 hours in an air atmosphere at the temperature of 250-500 ℃, and cooling to room temperature along with a furnace to obtain the environment-friendly bismuth vanadate pigment with the surface being coated and modified.
2. The method for preparing the in-situ coated multi-metal oxide high-performance bismuth vanadate pigment according to claim 1, wherein in the precursor preparation step, The bismuth-containing solution A is prepared by dissolving bismuth nitrate or bismuth oxide in nitric acid; the vanadium-containing solution B is prepared by dissolving ammonium metavanadate, vanadium pentoxide or sodium metavanadate in a NaOH solution; Wherein the concentration of nitric acid is the same as that of NaOH solution.
3. The method for preparing the in-situ coated multi-metal oxide high-performance bismuth vanadate pigment according to claim 1, wherein the coating agent solution is a single element coating agent solution or a multi-element coating agent solution, The single element coating agent solution is prepared by dissolving any one of Al salt, zr salt, zn salt, sn salt, la salt and Ce salt in deionized water; The multi-element coating agent solution is prepared by dissolving two or more of Al salt, zr salt, zn salt, sn salt, la salt and Ce salt in deionized water.
4. The method for preparing the in-situ coated multi-metal oxide high-performance bismuth vanadate pigment according to claim 3, wherein the Al salt is aluminum nitrate or aluminum chloride, the Zr salt is zirconium nitrate or zirconium oxychloride, the Zn salt is zinc nitrate or zinc sulfate, the Sn salt is tin tetrachloride or tin sulfate, the La salt is lanthanum nitrate or lanthanum chloride, and the Ce salt is cerium nitrate or cerium chloride.
5. The method for preparing the in-situ coated multi-metal oxide high-performance bismuth vanadate pigment according to claim 3, wherein in the in-situ deposition coating step, if the multi-layer coating modified bismuth vanadate pigment is prepared, a plurality of unit element coating agent solutions are sequentially added into the mixed solution C, and each unit element coating agent solution is stirred and reacted for 10-30 minutes after being added.
6. The method for preparing the in-situ coated multi-metal oxide high-performance bismuth vanadate pigment according to claim 1, wherein in the in-situ deposition coating step, Filtering by using a buchner funnel, filtering by using a sand core funnel or press filtering by using a plate frame; the washing adopts deionized water and absolute ethyl alcohol for alternating washing for 2-4 times respectively; The drying is carried out by adopting a vacuum drying oven, a blast drying oven or a microwave dryer, the drying temperature is 60-100 ℃, and the drying time is 0.5-24 hours.
7. The method for preparing the high-performance bismuth vanadate pigment coated with the multi-metal oxide in situ according to claim 1, wherein in the in situ deposition coating step, the pH value is adjusted by adding sodium hydroxide solution or nitric acid solution.
8. The method for preparing the in-situ coated multi-metal oxide high-performance bismuth vanadate pigment according to claim 1, wherein in the post-treatment step, a muffle furnace, a tube furnace, a pusher kiln or a rotary kiln is adopted for calcination.
9. The method for preparing the in-situ coated multi-metal oxide high-performance bismuth vanadate pigment according to claim 1, wherein the mass ratio and the distribution of each metal oxide in the coating layer are controlled by the use amount and the addition sequence of each metal salt in the coating agent solution.
10. The high-performance bismuth vanadate pigment coated with multi-metal oxide in situ, which is characterized in that the high-performance bismuth vanadate pigment is prepared by the method of any one of claims 1-9, and the surface of the pigment is provided with a coating layer with the thickness of 5-20 nm.

Description

High-performance bismuth vanadate pigment coated with multi-metal oxide in situ and preparation method thereof Technical Field The invention belongs to the technical field of inorganic pigment preparation, and particularly relates to a high-performance bismuth vanadate pigment coated with multi-metal oxide in situ and a preparation method thereof, which are suitable for the fields of building coatings, automobile coatings and the like with high requirements on color stability and durability. Background Bismuth vanadate (BiVO 4) is used as a novel environment-friendly yellow inorganic pigment, and is gradually replacing traditional heavy metal pigments such as lead chrome yellow, cadmium yellow and the like due to the excellent color, high covering power, good weather resistance and low toxicity, so that the bismuth vanadate is widely used in the fields of building coatings, automobile coatings, ceramic glaze materials and the like. However, different scenes have other properties than color properties for them, such as: acid and alkali resistance, weather resistance and the like are strictly required, and the application of the modified polyamide is limited in high-end paint and severe environment. For example, the building exterior wall coating needs to resist acid rain erosion and ultraviolet long-term irradiation, the color difference delta E is less than or equal to 2.0 after the pigment is soaked in 2% hydrochloric acid and sodium hydroxide solution for 24 hours, delta E is less than or equal to 3.0 after QUV is aged for 500 hours, and the automobile factory paint needs to withstand high-temperature baking (150-200 ℃) and extreme climate cycle, and the color stability delta E is less than or equal to 1.5. The pure monoclinic bismuth vanadate is difficult to meet the requirements, the comprehensive performance must be improved through surface coating modification, otherwise, the service life of the product is shortened due to fading and pulverization, and the maintenance cost is increased. In the current research on bismuth vanadate coating at home and abroad, oxides (such as Al 2O3、ZrO2、SiO2) become the main choice due to high chemical stability and good pigment compatibility. For example, chinese patent CN116023801B discloses a method for coating bismuth vanadate pigment powder, which comprises the steps of preparing bismuth vanadate slurry by using absolute ethyl alcohol, coating the bismuth vanadate slurry on a flat plate receiver of an electrostatic spinning machine, preparing a coating agent into coating agent sol, injecting the coating agent sol into the electrostatic spinning machine, repeatedly carrying out electrostatic spinning on the flat plate receiver coated with the bismuth vanadate slurry, removing the material after electrostatic spinning, and calcining to obtain the coated bismuth vanadate powder. The existing coating method mainly comprises a post-treatment process, bismuth vanadate particles are required to be prepared and then coated, and the obvious defects are that the coating layer and the substrate are combined only by physical adsorption, are easy to fall off under the condition of mechanical stirring or high temperature, so that the weather resistance is improved to a limited extent, and the particle aggregation is easy to cause uneven coating, so that the color performance is reduced. Therefore, development of a bismuth vanadate pigment powder coating technology is needed. Disclosure of Invention Aiming at the defects of the prior art, the preparation method and the application of the liquid-phase in-situ coating modified bismuth vanadate pigment are provided, and the composition and the structure of a coating layer are precisely regulated and controlled by in-situ coating a metal oxide layer in the preparation process of BiVO 4, so that the excellent color performance of the pigment is ensured, and meanwhile, the acid-base resistance, weather resistance and other performances of the pigment are obviously improved. In order to solve at least one of the technical problems, the invention adopts the following technical scheme: According to one aspect of the invention, the preparation method of the high-performance bismuth vanadate pigment with the in-situ coating of the multi-metal oxide comprises the steps of preparing a bismuth-containing solution A and a vanadium-containing solution B with the concentration of 0.1-2.0 mol/L respectively, preparing a coating agent solution, namely preparing a coating agent solution with the total concentration of 0.5-2.0 mol/L, carrying out in-situ deposition coating, namely mixing and reacting the bismuth-containing solution A and the vanadium-containing solution B at normal temperature for 30-90 minutes to obtain a mixed solution C, adding the coating agent solution into the mixed solution C, controlling the total metal ion content of the coating solution to be 5% -20% of the total content of vanadium bismuth, adjusting the pH value to be 5-8