1. The process for preparing from solution, lithoponeof various grades and a soluble commercial byproduct preferably of sodium, which consists in preparing separate solutions of zinc sulfate and barium'sulfid, which solutions are mixed with each other and with that of a third salt adapted to enter into combination with a freed acid group from the firstnamed salts, the same being brought together in equivalent and calculated amounts to produce and precipitate lithopone of the desired percentage, and leave in solution the soluble by-product, substantially as described.
Still, in 2016 Skittles publicly declared it would get rid of the chemical compound in its products, according to a press release at the time from the Center for Food Safety, which called the substance harmful and potentially poisonous. But the ingredient remains, according to the lawsuit, which alleges the candy company is misleading consumers by not having eliminated titanium dioxide.
Lithopone was discovered in the 1870s by DuPont. It was manufactured by Krebs Pigments and Chemical Company and other companies. The material came in different seals, which varied in the content of zinc sulfide. Gold seal and Bronze seals contain 40-50% zinc sulfide, offering more hiding power and strength. Although its popularity peaked around 1920, approximately 223,352 tons were produced in 1990. It is mainly used in paints, putty, and in plastics.
2. The preparation of the lining powder: The above-mentioned final immersion liquid 1000 ml in a 2000 ml beaker, heated to 98 ° C, and then added 4 g of ammonium persulfate with a magnetic stirrer stirring 0. 5h, after the oxidation of the solution, adding polyacrylamide 02%。 The solution, the volume of the solution is 0.02%. After lh filtration, the obtained filtrate is subjected to sulfurization and impurity removal, and zinc powder is substituted to obtain a zinc sulfate ammonia refining complex liquid. 122. 9g of antimony sulfide (without water) and 21. 7g of sodium sulfide (without water) are mixed and dissolved in distilled water to obtain a metathesis reaction solution, and a nonionic surfactant 0P-10 (for nonylphenol and epoxy) is added to the solution. The condensate of acetamidine) 0. 2g, the reaction temperature is 40 ° C, the stirring speed is 15m / s, stir well for 40min, then slowly added to 1000ml zinc sulfate ammonia refining complex, continue to stir for 30min and then add quality The fractionation is 30% 3⁄40 2 of desulfurization bleaching, and after bleaching, the nZnS-BaS0 4 crystal filter cake is separated by filtration.