china rutile and anatase titanium dioxide

It’s true that titanium dioxide does not rank as high for UVA protection as zinc oxide, it ends up being a small difference (think about it like being 10 years old versus 10 years and 3 months old). This is not easily understood in terms of other factors affecting how sunscreen actives perform (such as the base formula), so many, including some dermatologists, assume that zinc oxide is superior to titanium dioxide for UVA protection. When carefully formulated, titanium dioxide provides excellent UVA protection. Its UVA protection peak is lower than that of zinc oxide, but both continue to provide protection throughout the UVA range for the same amount of time.

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 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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