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US4220628A Expired / Lapsed US ⏱️ 0.0 years remaining

Production of lead monoxide from lead sulfate with acidic ammonium acetate

Assignee: NL Industries Inc
•
Filing: 1978-10-10
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Granted: 1980-09-02
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Expires: 1998-10-10
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Abstract

Abstract An efficient and inexpensive method for producing lead monoxide from impure 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 produce impure lead monoxide; (c) reacting said impure lead monoxide with an acidic ammonium acetate solution to form a lead acetate solution; (d) reacting ammonium hydroxide with the lead acetate solution to form lead hydroxide; and (e) dehydrating the lead hydroxide to produce lead monoxide.

Inventors

  • 👤 Eugene Striffler, Jr.
  • 👤 Michael A. Kolakowski

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-03 12:35
CPC Classifications
C; C01; C01G; C01G21/00; C01G21/02; C01G21/06; H; H01; H01M; H01M10/00; H01M10/54; C01P; C01P2002/00; C01P2002/70; C01P2002/76; C01P2006/00; C01P2006/60; C01P2006/80; Y; Y02; Y02W; Y02W30/00; Y02W30/50; Y02W30/84

Claims Analysis

Total Claims: 15
Claim 1
Independent Claim 106 words
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 the lead carbonate by heating at temperatures from about 400° to 650° C. to decompose substantially all of said lead carbonate to impure lead monoxide; (c) reacting the impure lead monoxide with an effective amount of acidic ammonium acetate solution to convert said lead monoxide to a lead acetate solution; (d) reacting the lead acetate solution with ammonium hydroxide to form lead hydroxide; and (e) dehydrating said lead hydroxide to produce lead monoxide.
Claim 2
Dependent Claim 106 words
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 the lead carbonate by heating at temperatures from about 400° to 650° C. to decompose substantially all of said lead carbonate to impure lead monoxide; (c) reacting the impure lead monoxide with an effective amount of acidic ammonium acetate solution to convert said lead monoxide to a lead acetate solution; (d) reacting the lead acetate solution with ammonium hydroxide to form lead hydroxide; and (e) dehydrating said lead hydroxide to produce lead monoxide.
Claim 3
Dependent Claim 20 words
The process of claim 1 wherein said ammonium carbonate solution contains from 1.5% to 12.5% by weight of ammonium carbonate.
Claim 4
Dependent Claim 41 words
The process of claim 1 wherein said lead sulfate bearing material contains lead dioxide and said lead dioxide is decomposed with said lead carbonate by reaction with acidic ammonium acetate and a reducing agent in step (b) to form lead acetate.
Claim 5
Dependent Claim 31 words
The process of claim 1 wherein said reaction of impure lead monoxide and acidic ammonium acetate in step (c) is carried out at temperatures of from about 20° to 80° C.
Claim 6
Dependent Claim 29 words
The process of claim 1 wherein the ratio of ammonia contained in said ammonium hydroxide to acetic acid in said lead acetate solution is from about 2 to 14.
Claim 7
Dependent Claim 25 words
The process of claim 1 wherein said ammonium hydroxide and said lead acetate solution in step (d) are reacted at from 15° to 80° C.
Claim 8
Dependent Claim 19 words
The process of claim 1 wherein said lead hydroxide is dehydrated by heating at from 145° to 180° C.
Claim 9
Dependent Claim 163 words
A process for producing substantially pure lead monoxide from solid lead sulfate bearing battery mud; which comprises: (a) reacting an aqueous dispersion of battery mud with an ammonium carbonate solution to form lead carbonate and an ammonium sulfate solution; (b) decomposing the lead carbonate by heating at temperatures from about 400° to 650° C. to decompose substantially all of said lead carbonate to impure lead monoxide; (c) reacting the impure lead monoxide with an effective amount of acidic ammonium acetate solution to convert said lead monoxide to a lead acetate solution; (d) reacting said impure lead monoxide with acidic ammonium acetate to form a soluble lead acetate solution and an insoluble residue; (e) separating said lead acetate solution from said insoluble residue; (f) adding ammonium hydroxide solution to said lead acetate solution to form insoluble lead hydroxide and ammonium acetate solution; (g) separating said lead hydroxide from said ammonium acetate solution; and (h) heating said lead hydroxide to form substantially pure lead monoxide.
Claim 10
Dependent Claim 163 words
A process for producing substantially pure lead monoxide from solid lead sulfate bearing battery mud; which comprises: (a) reacting an aqueous dispersion of battery mud with an ammonium carbonate solution to form lead carbonate and an ammonium sulfate solution; (b) decomposing the lead carbonate by heating at temperatures from about 400° to 650° C. to decompose substantially all of said lead carbonate to impure lead monoxide; (c) reacting the impure lead monoxide with an effective amount of acidic ammonium acetate solution to convert said lead monoxide to a lead acetate solution; (d) reacting said impure lead monoxide with acidic ammonium acetate to form a soluble lead acetate solution and an insoluble residue; (e) separating said lead acetate solution from said insoluble residue; (f) adding ammonium hydroxide solution to said lead acetate solution to form insoluble lead hydroxide and ammonium acetate solution; (g) separating said lead hydroxide from said ammonium acetate solution; and (h) heating said lead hydroxide to form substantially pure lead monoxide.
Claim 11
Dependent Claim 17 words
The process of claim 8 wherein step (a) is conducted at between about 25° to 35° C.
Claim 12
Dependent Claim 31 words
The process of claim 8 wherein said reaction of impure lead monoxide and acidic ammonium acetate in step (c) is carried out at temperatures of from about 20° to 80° C.
Claim 13
Dependent Claim 30 words
The process of claim 8 wherein the ratio of ammonia contained in said ammonium hydroxide solution to acetic acid in said lead acetate solution is from about 2 to 14.
Claim 14
Dependent Claim 26 words
The process of claim 8 wherein said ammonium hydroxide and said lead acetate solution in step (f) are reacted at from 15° C. to 80° C.
Claim 15
Dependent Claim 53 words
The process of claim 8 wherein said ammonium acetate solution of step (g) is distilled to form a distillate consisting of ammonia and ammonium hydroxide solution and a residue of acid ammonium acetate; said acid ammonium acetate being used in step (d) and said ammonia and ammonium hydroxide being used in step (f).

References Cited (Backward Citations)

US509057A Cited
US3194633A Cited
US3230043A Cited
US3497382A Cited
US4118219A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1983-09-02 1984-03-03 1984-09-02 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1987-09-02 1988-03-03 1988-09-02 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1991-09-02 1992-03-03 1992-09-02 $7700.00 Window Closed / Lapsed

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