r902 titanium dioxide

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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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Leading titanium dioxide manufacturers have started to explore alternative synthesis routes that minimize waste and reduce energy consumption. For instance, some have turned to the sol-gel process, which allows for the production of nanoparticles at lower temperatures with better control over the particle size distribution. Others are looking into recycling waste streams from the manufacturing process to recover titanium compounds, thus closing the loop on material use Others are looking into recycling waste streams from the manufacturing process to recover titanium compounds, thus closing the loop on material use Others are looking into recycling waste streams from the manufacturing process to recover titanium compounds, thus closing the loop on material use Others are looking into recycling waste streams from the manufacturing process to recover titanium compounds, thus closing the loop on material usetitanium dioxid manufacturer.

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