Patent US4600699A successfully refreshed from Google Patents.
US4600699A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Reclamation of a palladium-tin based electroless plating catalyst from the exhausted catalyst solution and accompanying rinse waters
Assignee: MacDermid Enthone Inc
•
Filing: 1983-02-14
•
Granted: 1986-07-15
•
Expires: 2003-02-14
Abstract
Abstract A method for the recovery and reuse of an expensive palladium-tin catalyst whereby alkali hydroxide or carbonate is added to the exhausted catalytic solution and/or the spent rinse water solution to precipitate out a catalyst residue, which is then filtered, collected, washed, and dissolved in a hydrohalide acid and adjusted to a predetermined concentration.
Inventors
- 👤 Constantine I. Courduvelis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 06:18
CPC Classifications
B; B01; B01J; B01J23/00; B01J23/90; B01J23/96; C; C22; C22B; C22B11/00; C22B11/04; C22B11/042; C22B11/048; C22B25/00; C22B25/06; C22B7/00; C22B7/009; C23; C23C; C23C18/00; C23C18/16; C23C18/1601; C23C18/1617; Y; Y02; Y02P; Y02P10/00; Y02P10/20
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
86 words
A method for the reclamation for reuse of an electroless plating precious metal-tin catalyst from a weakened aqueous electroless plating activator solution and/or the spent rinse water solution comprising: precipitating a precious metal-tin catalyst residue out of the solution by adding an effective amount of a base selected from the group of alkali hydroxides and alkali salts of weak-inorganic and organic acids to the weakened precious metal-tin catalyst activator solution and/or the spent rinse water solution; and filtering and collecting the precipitated residue from the solution.
Claim 2
Independent Claim
86 words
A method for the reclamation for reuse of an electroless plating precious metal-tin catalyst from a weakened aqueous electroless plating activator solution and/or the spent rinse water solution comprising: precipitating a precious metal-tin catalyst residue out of the solution by adding an effective amount of a base selected from the group of alkali hydroxides and alkali salts of weak-inorganic and organic acids to the weakened precious metal-tin catalyst activator solution and/or the spent rinse water solution; and filtering and collecting the precipitated residue from the solution.
Claim 3
Dependent Claim
36 words
A method as in claim 1 wherein the precipitated residue is further treated by: (d) dissolving the residue in an effective amount of a hydrohalide acid; and (e) adjusting the resulting solution to a desired concentration.
Claim 4
Dependent Claim
19 words
A method as in claim 2 wherein the solution from step (e) is recycled back to the catalyst solution.
Claim 5
Dependent Claim
24 words
A method as in claim 1 or 2 wherein the solutions are kept under an oxidation resistant atmosphere during the addition of the base.
Claim 6
Dependent Claim
23 words
A method as in claim 4 wherein the oxidation resistant atmosphere is selected from the group consisting of nitrogen and CO 2 gases.
Claim 7
Dependent Claim
26 words
A method as in claim 1 or 2 wherein the base added is an aqueous solution selected from the group of alkali metal hydroxides and carbonates.
Claim 8
Dependent Claim
14 words
A method as in claim 1 or 2 wherein the precious metal is palladium.
Claim 9
Dependent Claim
36 words
A method as in claim 1 or 2 wherein the addition of the base in accompanied by a predetermined cooling of the solution so as to prevent a substantial temperature rise in the solution from occurring.
Claim 10
Dependent Claim
29 words
A method as in claim 1 or 2 wherein the addition of the base is continued until the pH of the solution has risen to about 5 to 8.
Claim 11
Dependent Claim
14 words
A method as in claim 1 or 2 wherein the hydrohalide acid is HCl.
Claim 12
Dependent Claim
22 words
A method as in claim 2 wherein the resulting regenerated solution is substantially equivalent in catalytic strength to the original catalyst solution.
References Cited (Backward Citations)
US4187198A
Cited
DE2742777A1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-07-14 | 1990-01-13 | 1990-07-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-07-14 | 1994-01-13 | 1994-07-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-07-14 | 1998-01-13 | 1998-07-15 | $7700.00 | Window Closed / Lapsed |