Environmental-friendly pigment bismuth yellow and production method thereof

Abstract

The invention relates to environmental-friendly pigment bismuth yellow and a production method thereof. The production method is characterized by comprising the steps of: firstly placing solid bismuth into a mixed acid solution made of nitric acid and hydrochloric acid for soaking, then taking out for reacting with a nitric acid solution to obtain a bismuth nitrate solution; keeping the nitric acid in an excessive state, then mixing and dissolving ammonium metavanadate or ammonium metavanadate and ammonium molybdate into ammonia water to obtain a vanadium-containing or vanadium and molybdenum-containing ammonia water mixed solution; under the condition of continuously stirring, simultaneously adding the bismuth nitrate solution and the mixed solution into a reactor containing a dispersing agent and a bottom fluid to obtain a light yellow sediment; and washing, drying and pulverizing according to a conventional method, finally, calcining and sieving to obtain the environmental-friendly pigment bismuth yellow with uniform granularity. The invention has the advantages of easy control of process conditions, good product dispersity, fine and uniform granularity, good powder activity, wide source and high utilization ratio of raw materials and better economic feasibility.

Description

technical field [0001] The invention relates to a pigment and a production method thereof, in particular to a pigment bismuth yellow and a production method thereof. Background technique [0002] Pigment is one of the indispensable components of various coatings. The function of pigment is not only color and decoration, but especially important is that it can improve the strength, anti-corrosion, light resistance and weather resistance of the coating film. The existing inorganic pigments on the market may fade easily in the air due to their dark color, that is, they are not resistant to weather, especially not resistant to SO in the atmosphere 2 Gas corrosion; or because of containing lead, cadmium, chromium and other toxic heavy metals, its application in many fields is limited. Bismuth and its compounds have excellent properties such as non-toxicity, corrosion resistance and good color. Bismuth yellow prepared with bismuth as the main body, vanadium and molybdenum as the ...

AI Technical Summary

Problems solved by technology

[0003] At present, the main preparation methods of bismuth yellow in the prior art include solid-phase calcination, forced hydrolysis, wet grinding and co-precipitation. The solid-phase calcination has the disadvantages of high temperature and coarse product particle size, which limits its use. Application; the forced hydrolysis method needs to strictly control the preparation conditions such as temperature and pH value, and the obtained product particle size is relatively coarse, so the application of this method is also subject to certain restrictions; the wet grinding method is to combine bismuth (III) compound with vanadium (V ) compounds are mixed together, and the pH value is controlled for wet grinding. This method is easy to bring in impurities, and has the disadvantages of high energy consumption and poor product quality, so it is difficult to apply in industry; the co-precipitation method is currently the most widely used method for preparing bismuth yellow. , this method can well overcome the above-mentioned shortcomings, but because sodium hydroxide is used as a precipitating agent and a pH value adjusting agent, the sodium salt in the solution is not easy to wash off, and it is also difficult to be decomposed and removed during calcination, and the dispersibility of the product is also low. Poor, it is necessary to add organic additives such as dispersants to improve the dispersion performance of the product, but adding dispersants will affect the quality and performance of bismuth yellow

Chinese patent 200710095910.2 discloses a preparation method of an ultrafine bismuth vanadate yellow pigment, which uses bismuth nitrate, metavanadate or vanadate as raw materials, and the solvent for dissolving metavanadate or vanadate is nitric acid aqueous solution or The aqueous solution of sodium hydroxide, though can reach its purpose of preparing superfine bismuth vanadate yellow pigment, but this method directly uses bismuth nitrate as raw material, and cost height does not have economic feasibility, and this method adopts sodium hydroxide to make solvent and pH Adjusting agent, not only the pH value is difficult to control, but also the sodium salt in the solution is not easy to wash off, and the sodium salt is also difficult to decompose and remove during calcination, which in turn affects the quality and performance of the pigment bismuth yellow

Chinese patent 200710061841.3 discloses the production process of high-temperature-resistant bismuth vanadate yellow ceramic pigments, and its yellow pigment BiVO 4 In the preparation process, bismuth nitrate is directly used as raw material, and sodium hydroxide is used as solvent, which also has defects similar to Chinese patent 200710095910.2

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