lithopone is a mixture of

To make up the batch of lithopone the solution containing the original 1050 pounds of barium sulphide and 856 pounds of titanium acid cake is added to sufiicient zinc sulphate solution of approximately 35 Baum at 60 Centigrade to completely precipitate all the BaS as zinc sulphide and barium sulphate so that the final precipitate contains a suspen-. sion of co-p'recipitated zinc sulphide barium sulphate intimately mixed with a suspension of titanium oxide. On the completion of the reaction, shown by the complete absence of either soluble zinc or barium in a filtered por-.

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3) Metathesis reaction: Dissolve the sulfide in distilled water to obtain a clear decomposition liquid, and add nonionic surfactant to stir evenly, then slowly add it to the zinc sulfate ammonia complex solution to form a metathesis reaction, and obtain Lide powder opacity. The liquid is separated by filtration, and the separated ammonia liquid is returned to the leaching after ammonia adjustment, and the separated nZnS-BaS0 4 crystal filter cake is put into the next step;

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