lithopone pigment

However, the journey hasn't been without challenges. Environmental concerns, stringent regulations, and fluctuations in raw material prices have posed hurdles for the industry Environmental concerns, stringent regulations, and fluctuations in raw material prices have posed hurdles for the industry Environmental concerns, stringent regulations, and fluctuations in raw material prices have posed hurdles for the industry Environmental concerns, stringent regulations, and fluctuations in raw material prices have posed hurdles for the industrychina billions tio2. Despite these, Chinese manufacturers have demonstrated resilience through innovation and technological advancements, improving efficiency and reducing environmental impact.

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The factory's production process is a testament to precision and optimization. Raw materials, primarily ilmenite, rutile, and anatase ores, undergo a rigorous refining process that includes crushing, leaching, and solvent extraction methods. These steps ensure the purity and consistency required for high-quality pigments. Following this, gaseous chlorination converts the refined ore into titanium tetrachloride, setting the stage for the final synthesis of titanium dioxide through the oxidation of titanium tetrachloride in a heated environment.

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Lithopone B301, Lithopone B311 powder, brilliant white pigment used in paints, inks, leather, paper, linoleum, and face powder. It was developed in the 1870s as a substitute or supplement for lead carbonate (white lead), to overcome its drawbacks of toxicity, poor weathering, and darkening in atmospheres that contain sulfur compounds. Lithopone B301, Lithopone B311 powder is an insoluble mixture of barium sulfate and zinc sulfide that precipitates upon mixing solutions of barium sulfide and zinc sulfate. The precipitate is recovered by filtration, then calcined (roasted) at temperatures above 600° C (1,112° F). Although Lithopone B301, Lithopone B311 powder has been replaced in many applications by titanium dioxide, it is still widely used in a number of products, such as water paints.

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At present, the domestic wet zinc smelting mainly adopts the roasting-leaching-electrowinning production process, and the zinc content in the acid leaching residue is generally 8-15%, some up to 20%, and the sulfur mass fraction is 6-12%, of which sulfuric acid The root mass fraction is 15-30%, mainly in the form of 0^0 4 (in this ammoniatic environment, the leaching rate of sulfate leaching in multiple stages can reach 70%). The zinc in the acid leaching residue is mainly in the form of ZnFe 2 0 4 . In order to recover these zinc, the treatment methods are currently available in the fire method and the wet method. The fire method is the rotary kiln evaporation method (Wilz method) and the fumigating furnace evaporation method. . The wet method has hot acid leaching or high temperature pressure leaching. The fire treatment process is long, the equipment maintenance is large, the investment is high, the working environment is poor, and a large amount of coal or metallurgical coking coal is consumed, which has low efficiency and large environmental pollution. Therefore, it is usually leached by hot acid or high-pressure leaching. These methods still have the disadvantages of: 1 consumption of a large amount of acid, low leaching rate, due to the large amount of calcium sulfate, calcium sulphate and other ultrafine particles to isolate the zinc oxide particles, resulting in Electrolytic zinc enterprises are difficult to leach in acid environment, and the second weak acid leaching is not meaningful because the recovery rate is too low. 2 If leached with strong acid, although ZnFe 2 0 4 is destroyed, the leaching rate is improved, but the iron leaching rate is also high (up to 60%). The pressure of iron removal is large, and more reagents are consumed. 3 High temperature and high pressure equipment is corroded. Serious, complicated equipment investment; 4 high operating costs, poor economic returns. 5 The last slag discharged is acid leaching residue, which brings new pollution to the environment. It has to be cured and landfilled, which not only pollutes the environment, but also wastes resources.

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