fumed titanium dioxide

Although barium sulfate is almost completely inert, zinc sulfide degrades upon exposure to UV light, leading to darkening of the pigment. The severity of this UV reaction is dependent on a combination of two factors; how much zinc sulfide makes up the pigments formulation, and its total accumulated UV exposure. Depending on these factors Lithopone B301, Lithopone B311 powder itself may vary in shade over time, ranging from pure white all the way to grey or even black. To suppress this effect, a dopant might be used, like small amount of cobalt salts, which would be added to the formulation. This process creates cobalt-doped zinc sulfide. The cobalt salts help to stabilize zinc sulfide so it will not have as severe a reaction to UV exposure.

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In addition, with the increasing demand for zinc compounds and lithopone, the continuous exploitation of zinc resources in China, the increasingly poor, fine and complex mineral resources, the comprehensive utilization and environmental protection requirements continue to improve, people have begun to study the recovery of low-zinc raw materials. Use technology. The so-called low-zinc raw materials are mainly low-grade zinc oxide ore, but in addition to low-grade oxidation In addition to zinc in zinc ore, zinc is also present in the acid leaching residue.

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② Plastics: At present, it is the second largest user of titanium dioxide pigments, accounting for about 20% of the total demand for titanium dioxide. The amount of titanium dioxide used in plastic products will vary with the use requirements, generally between 0.5% and 5%. According to data from the National Bureau of Statistics, the production of plastic products in China increased from 57.81 million tons in 2012 to 81.84 million tons in 2019, with a compound annual growth rate of 5.1%. The amount of titanium dioxide increases accordingly.

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Lithopone is produced by coprecipitation of barium sulfate and zinc sulfide. Most commonly coprecipitation is effected by combining equimolar amounts of zinc sulfate and barium sulfide:

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  • However, China's Tio2 pigment industry is not without challenges
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