Method for removing As, or As and Sb and/or Bi from sulfuric acid
AssigneeSumitomo Metal Mining Co., Ltd.
InventorsSeiichi Murakita, Akio Ohta, Satoshi Narahara
Life of this patent
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Abstract
A method for removing As, or As and Sb and/or Bi wherein acidic solution of sulfuric acid such as a copper electrolyte of having a free sulfuric acid concentration of less than 700g./l. and containing at least arsenic among arsenic, antimony and bismuth as impurities is warmed to be above 50.degree. C. or preferably above 60.degree. C. with the addition of H.sub.3 AsO.sub.4 in advance as required, one or a mixture of both of Sb.sub.2 O.sub.3 and Bi.sub.2 O.sub.3 preferably kneaded with water or the added solution is added to and mixed with the solution and the produced precipitate is separated to discharge the impurities out of the solution.
Claims44
A method for reducing the concentration of As in acidic solutions of sulfuric acid comprising providing an acidic solution of sulfuric acid having a free sulfuric acid concentration of less than 700 g./l. and containing arsenic as an impurity, warming the acidic solution to about 50.degree. C., adding the mixing to the solution an additive selected from the group consisting of Sb.sub.2 O.sub.3, Bi.sub.2 O.sub.3 and mixtures thereof, allowing the solution to react with the additive for a time sufficient to cause some of the arsenic impurity to precipitate so that the concentration of arsenic in the solution is less than the initial concentration of arsenic in the solution, and separating the produced precipitate from the solution.
A method for reducing the concentration of As and Sb in acidic solutions of sulfuric acid comprising providing an acidic solution of sulfuric acid having a free sulfuric acid concentration of less than 700 g./l. and containing arsenic acid antimony as impurities, warming the acidic solution to above 50.degree. C., adding the mixing to the solution an additive selected from the group consisting of Sb.sub.2 O.sub.3, Bi.sub.2 O.sub.3 and mixtures thereof, allowing the solution to react with the additive for a time sufficient to cause some of each of the contained impurities to precipitate so that the concentration of arsenic and antimony in the solution is less than the initial concentration of arsenic and antimony in the solution, and separating the produced precipitate from the solution.
A method for reducing the concentration of As and Bi in acidic solutions of sulfuric acid comprising providing an acidic solution of sulfuric acid having a free sulfuric acid concentration of less than 700 g./l. and containing arsenic and bismuth as impurities, warming the acidic solution to above 50.degree. C., adding and mixing to the solution an additive selected from the group consisting of Sb.sub.2 O.sub.3, Bi.sub.2 O.sub.3 and mixtures thereof, allowing the solution to react with the additive for a time sufficient to cause some of each of the contained impurities to precipitate so that the concentration of arsenic and bismuth in the solution is less than the initial concentration of arsenic and bismuth in the solution, and separating the produced precipitate from the solution.
A method for reducing the concentration of As, Sb and Bi in acidic solutions of sulfuric acid comprising providing an acidic solution of sulfuric acid having a free sulfuric acid concentration of less than 700 g./l. and containing arsenic, antimony and bismuth as impurities, warming the acidic solution to above 50.degree. C., adding and mixing to the solution an additive selected from the group consisting of Sb.sub.2 O.sub.3, Bi.sub.2 O.sub.3 and mixtures thereof, allowing the solution to react with the additive for a time sufficient to cause some of each of the contained impurities to precipitate so that the concentration of arsenic, antimony and bismuth in the solution is less than the initial concentration of arsenic, antimony and bismuth in the solution, and separating the produced precipitate from the solution.
Dependencies are inferred from the claim text.