yellow oxide of iron and titanium dioxide factory

China's dominance in the titanium dioxide industry can be attributed to its vast mineral resources, particularly ilmenite and rutile, which are the primary sources of titanium dioxide. The country possesses an estimated 45% of the world's total titanium reserves, enabling it to maintain a consistent and large-scale production capacity. This has not only secured China's position as a leading producer but also influenced global market dynamics.

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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 the pigment itself can vary in shade over time, ranging from pure white all the way to grey or even black. To suppress this effect, a dopant may be used, such as a 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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