Production of lead monoxide from lead sulfate with acetic acid
AssigneeNL Industries, Inc.
InventorsEugene Striffler, Jr., Michael A. Kolakowski
Life of this patent
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Abstract
An efficient and inexpensive method for producing lead monoxide from lead sulfate bearing materials such as recycled battery mud is provided comprising: (a) reacting said material with an ammonium carbonate solution to convert lead sulfate to lead carbonate; (b) decomposing the lead carbonate to form impure lead monoxide; (c) reacting the impure lead monoxide with acetic acid to form a lead acetate solution; (d) contacting the lead acetate solution with carbon dioxide to produce insoluble lead carbonate; and (e) decomposing the lead carbonate to form lead monoxide.
Claims17
A process for producing lead monoxide from solid lead sulfate bearing material which comprises:
- (a) reacting said material with an ammonium carbonate solution to convert said lead sulfate to lead carbonate;
- (b) decomposing substantially all of the lead carbonate to impure lead monoxide by heating at temperatures from about 400.degree. to 650.degree. C.,
- (c) reacting the impure lead monoxide with an effective amount of an acetic acid solution to convert said lead monoxide to a lead acetate solution;
- (d) separating said lead acetate solution from the insoluble impurities;
- (e) contacting the lead acetate solution from step (d) with carbon dioxide gas to form lead carbonate;
- and
- (f) decomposing the lead carbonate to produce lead monoxide.
A process for producing substantially pure lead monoxide from solid lead sulfate bearing battery mud, which comprises:
- (a) reacting an aqueous dispersion of said battery mud with an ammonium carbonate solution to form lead carbonate and an ammonium sulfate solution;
- (b) separating said ammonium sulfate solution from said lead carbonate;
- (c) heating said lead carbonate to between about 400.degree. to 650.degree. C. to decompose substantially all of said lead carbonate to impure lead monoxide;
- (d) reacting said impure lead monoxide with acetic acid solution to convert said lead monoxide to a soluble lead acetate solution and an insoluble residue;
- (e) separating said lead acetate solution from said insoluble residue;
- (f) contacting said lead acetate solution from step (e) carbon dioxide gas to form insoluble lead carbonate and acetic acid solution;
- (g) separating said lead carbonate from said acetic acid solution;
- and
- (h) heating said lead carbonate to form substantially pure lead monoxide.
A process for the continuous production of substantially pure lead monoxide from solid lead sulfate bearing material containing lead dioxide which comprises:
- (a) reacting said material with an ammonium carbonate solution to form lead carbonate and an ammonium sulfate solution;
- (b) separating the ammonium sulfate solution from the lead carbonate;
- (c) heating said lead carbonate to between about 400.degree. to 650.degree. C. to decompose substantially all f said lead carbonate to impure lead monoxide;
- (d) reacting the lead monoxide with an effective amount of acetic acid solution to convert said lead monoxide to lead acetate solution and an insoluble residue;
- (e) separating said insoluble residue from said lead acetate solution;
- (f) contacting said lead acetate solution from step (e) with carbon dioxide gas to form lead carbonate and by-product acetic acid solution;
- (g) separating said by-product acetic acid solution from said lead carbonate, said by-product acetic acid solution being used as the acetic acid reactant in step (d) and
- (h) decomposing said lead carbonate to form substantially pure lead monoxide and a second by-product carbon dioxide gas which is separated from said pure lead monoxide.
A process for producing lead monoxide from solid lead sulfate bearing material, comprising:
- (a) reacting said lead sulfate bearing material with an ammonium carbonate solution containing from 1.5% to 12.5% by weight of ammonium carbonate to convert said lead sulfate to lead carbonate;
- (b) decomposing substantially all of the lead carbonate to impure lead monoxide by heating to between about 400.degree. to 650.degree. C.;
- (c) reacting the impure lead monoxide with an acetic acid solution having a concentration of from 0.1% to 15% acetic acid and further wherein said acetic acid is added to the impure lead monoxide at a mole ratio of acetate to reactive lead of 1:0.9 to 1.1;
- (d) separating said lead acetate solution from the insoluble impurities;
- (e) contacting the lead acetate solution from step (d) with carbon dioxide gas to form lead carbonate;
- and
- (f) decomposing the lead carbonate to produce lead monoxide.
Dependencies are inferred from the claim text.