lithopone 30% factories

In terms of production, China is the largest producer of both calcium carbonate and titanium dioxide in the world. The country has abundant reserves of both minerals and a well-developed mining and processing industry
china
china calcium carbonate vs titanium dioxide. China's calcium carbonate production is concentrated in regions such as Guangdong, Guangxi, and Jiangsu, while titanium dioxide production is centered in provinces such as Shandong, Henan, and Sichuan.

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 At present, Lide powder is mainly produced in China. Most of the domestic Lide powder production is still using traditional methods. The main raw materials are zinc oxide, sulfuric acid and barium sulfide (barite and coal are produced by high temperature reduction). Zinc 45% ~ 70%. The traditional method for producing the Liede powder process is to use zinc bakelite containing more than 45% zinc as a raw material to be leached with sulfuric acid to obtain a crude zinc sulfate solution, and then to remove iron by potassium permanganate, and then replace the heavy metal with zinc powder and filter to obtain zinc sulfate. The refined liquid is further subjected to metathesis reaction, pressure filtration, calcination, rinsing, drying, and pulverization with strontium sulfide to obtain a series of different types of lindose powder containing zinc sulfide of 30% or more. The whole process is carried out in an acidic (ra<7) environment, which consumes a large amount of sulfuric acid. The sulfuric acid has strong corrosiveness and requires high production equipment. The final discharged slag is acidic slag, which brings new pollution to the environment. High requirements, high production costs, and poor quality of the products obtained.

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The main concern with nanoparticles is that they are so tiny that they are absorbed into the skin more than we want them (ideally sunscreen should remain on the surface of the skin). Once absorbed they might form unwanted complexes with proteins and they might promote the formation of evil free radicals. But do not panic, these are concerns under investigation. A 2009 review article about the safety of nanoparticles summarizes this, to date, in-vivo and in-vitro studies have not demonstrated percutaneous penetration of nanosized particles in titanium dioxide and zinc oxide sunscreens. The English translation is, so far it looks like sunscreens with nanoparticles do stay on the surface of the skin where they should be.  

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{随机栏目} 2025-08-15 00:24 176