US4103000A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for preparing copper arsenate compositions
Assignee: Hickson Corp
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Filing: 1974-05-23
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Granted: 1978-07-25
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Expires: 1994-05-23
Abstract
Abstract The present invention is directed to copper arsenate compositions which are useful in preparing chromated copper arsenate wood preserving formulations. The copper arsenate compositions are slurries of insoluble copper arsenates in an aqueous solution of copper arsenates. The copper arsenate slurries have a mole ratio of As 2 O 5 to CuO of from about 0.3:1 to about 0.9:1 and are readily soluble in chromic acid to form chromated copper arsenate solutions. The copper arsenate slurries are prepared by reacting copper metal with arsenic acid in the presence of an acid catalyst and an oxidizing agent.
Inventors
- 👤 Winslow H. Hartford
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 23:17
CPC Classifications
C; C01; C01G; C01G28/00; C01G28/02; C01G28/007; C01P; C01P2006/00; C01P2006/80
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
132 words
A method for making copper arsenate compositions which consist essentially of a slurry of water insoluble copper arsenate in an aqueous solution of soluble copper arsenate wherein the mole ratio of arsenic measured as As 2 O 5 to copper measured as CuO of the overall copper arsenate composition is within the range of from about 0.3:1.0 to 0.9:1.0 and wherein the copper arsenate composition is soluble in chromic acid comprising reacting copper metal with arsenic acid in the presence of an oxidizing agent and an acid catalyst selected from the group consisting of nitric acid, hydrochloric acid and sulfuric acid wherein the copper and arsenic acid are proportioned to produce a copper arsenate composition having a mole ratio of As 2 O 5 to CuO of from about 0.3:1.0 to 0.9:1.0.
Claim 2
Independent Claim
132 words
A method for making copper arsenate compositions which consist essentially of a slurry of water insoluble copper arsenate in an aqueous solution of soluble copper arsenate wherein the mole ratio of arsenic measured as As 2 O 5 to copper measured as CuO of the overall copper arsenate composition is within the range of from about 0.3:1.0 to 0.9:1.0 and wherein the copper arsenate composition is soluble in chromic acid comprising reacting copper metal with arsenic acid in the presence of an oxidizing agent and an acid catalyst selected from the group consisting of nitric acid, hydrochloric acid and sulfuric acid wherein the copper and arsenic acid are proportioned to produce a copper arsenate composition having a mole ratio of As 2 O 5 to CuO of from about 0.3:1.0 to 0.9:1.0.
Claim 3
Dependent Claim
12 words
A method as in claim 1 wherein the oxidizing agent is oxygen.
Claim 4
Dependent Claim
12 words
A method as in claim 1 wherein the catalyst is nitric acid.
Claim 5
Dependent Claim
16 words
A method as in claim 1 wherein a combination of nitric acid and oxygen is used.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-07-24 | 1982-01-23 | 1982-07-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-07-24 | 1986-01-23 | 1986-07-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-07-24 | 1990-01-23 | 1990-07-25 | $7700.00 | Window Closed / Lapsed |