r104 tio2

 2) Purification: Add ammonium persulfate to the final immersion solution for one-time oxidation and iron removal, and add activated carbon to adsorb arsenic and iron co-precipitation to achieve the purpose of removing arsenic. Add the polyacrylamide coagulant to separate and filter before separation. The sulfide solution is added to the solution to remove sulfur, and the separated filtrate obtained by the separation is replaced with zinc powder to remove the remaining impurities to obtain a zinc sulfate ammonia complex liquid, which is used in the next step;

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r104 tio22025-08-16 02:38
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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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r104 tio22025-08-16 00:01
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