77891 titanium dioxide

 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 brands of lithopone of the normal class, that of chemical manufacture, are marketed under such names as Ponolith, Beckton White, Jersey Lily White, Oleum White, Zinc Sulphide White, all of these being of domestic manufacture, and their composition is of the 30 per cent. zinc sulphide type. The German manufacturers and exporters of lithopone make use of fancy names for their brands and here are a few examples of these and the composition of the pigment:-

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