US4220628A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Production of lead monoxide from lead sulfate with acidic ammonium acetate
Assignee: NL Industries Inc
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Filing: 1978-10-10
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Granted: 1980-09-02
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Expires: 1998-10-10
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)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 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 |