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US4437928A
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Dissolution of metals utilizing a glycol ether
Assignee: Plastic Specialties and Technologies Inc
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Filing: 1983-08-22
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Granted: 1984-03-20
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Expires: 2003-08-22
Abstract
Abstract Improved metal dissolution rates are obtained when using a solution containing sulfuric acid, hydrogen peroxide and a catalytic amount of a glycol ether such as diethylene glycol butyl ether or ethylene glycol butyl ether.
Inventors
- 👤 Kwee C. Wong
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 21:57
CPC Classifications
C; C23; C23F; C23F1/00; C23F1/10; C23F1/14; C23F1/16
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
50 words
A method of metal dissolution which comprises contacting a metal with an aqueous solution containing from about 0.2 to about 4.5 gram moles per liter of sulfuric acid, from about 0.25 to about 8 gram moles per liter of hydrogen peroxide and a catalytically effective amount of a glycol ether.
Claim 2
Independent Claim
50 words
A method of metal dissolution which comprises contacting a metal with an aqueous solution containing from about 0.2 to about 4.5 gram moles per liter of sulfuric acid, from about 0.25 to about 8 gram moles per liter of hydrogen peroxide and a catalytically effective amount of a glycol ether.
Claim 3
Dependent Claim
21 words
The method of claim 1, wherein said additive is provided at a concentration of at least about 2 millimoles per liter.
Claim 4
Dependent Claim
25 words
The method of claim 1, wherein said additive is provided at a concentration in the range from about 5 to about 50 millimoles per liter.
Claim 5
Dependent Claim
27 words
The method of claim 1, wherein the aqueous solution contains sodium phenolsulfonate as a stabilizer to reduce the degrading effect of heavy metal ions on hydrogen peroxide.
Claim 6
Dependent Claim
22 words
The method of claim 1, wherein the hydrogen peroxide concentration is maintained between about 1 and about 4 gram moles per liter.
Claim 7
Dependent Claim
22 words
The method of claim 1, wherein the sulfuric acid concentration is maintained between about 0.3 and about 4 gram moles per liter.
Claim 8
Dependent Claim
15 words
The method of claim 1, wherein the metal is copper or an alloy of copper.
Claim 9
Dependent Claim
25 words
The method of claim 1, wherein the dissolution is carried out in the presence of free chloride or bromide ions in excess of 2 ppm.
Claim 10
Dependent Claim
14 words
The method of claim 1 wherein the glycol ether is ethylene glycol butyl ether.
Claim 11
Dependent Claim
14 words
The method of claim 1 wherein the glycol ether is diethylene glycol butyl ether.
Claim 12
Dependent Claim
45 words
A composition for metal dissolution comprising an aqueous solution of from about 2.0 to about 4.5 gram moles per liter of sulfuric acid, from about 0.25 to about 8 gram moles per liter of hydrogen peroxide and a catalytically effective amount of a glycol ether.
Claim 13
Dependent Claim
45 words
A composition for metal dissolution comprising an aqueous solution of from about 2.0 to about 4.5 gram moles per liter of sulfuric acid, from about 0.25 to about 8 gram moles per liter of hydrogen peroxide and a catalytically effective amount of a glycol ether.
Claim 14
Dependent Claim
21 words
The composition of claim 11, wherein the additive is provided at a concentration of at least about 2 millimoles per liter.
Claim 15
Dependent Claim
25 words
The composition of claim 11, wherein the additive is provided at a concentration in the range from about 5 to about 50 millimoles per liter.
Claim 16
Dependent Claim
24 words
The composition of claim 11, additionally containing sodium phenolsulfonate as a stabilizer for reducing the degrading effect of heavy metal ions on hydrogen peroxide.
Claim 17
Dependent Claim
22 words
The composition of claim 11, wherein the hydrogen peroxide concentration is maintained between about 1 and about 4 gram moles per liter.
Claim 18
Dependent Claim
22 words
The composition of claim 11, wherein the sulfuric acid concentration is maintained between about 0.3 and about 4 gram moles per liter.
Claim 19
Dependent Claim
16 words
The composition of claim 11, containing more than 2 ppm of free chloride or bromide ions.
Claim 20
Dependent Claim
14 words
The composition of claim 11 wherein the glycol ether is ethylene glycol butyl ether.
Claim 21
Dependent Claim
14 words
The composition of claim 11 wherein the glycol ether is diethylene glycol butyl ether.
References Cited (Backward Citations)
US4236957A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-03-20 | 1987-09-19 | 1988-03-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-03-20 | 1991-09-19 | 1992-03-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-03-20 | 1995-09-19 | 1996-03-20 | $7700.00 | Window Closed / Lapsed |