US4496470A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Cleaning composition
Assignee: Goodrich Corp
•
Filing: 1982-01-12
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Granted: 1985-01-29
•
Expires: 2002-01-12
Abstract
Abstract A composition for cleaning fouled reverse osmosis membranes or other similar fouled surfaces. The composition will remove calcium and magnesium scale as well as iron scale and organic fouling materials. The composition is biodegradable and safe to use.
Inventors
- 👤 Anita G. Kapiloff
- 👤 Randolph T. Hatch
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 13:44
CPC Classifications
C; C02; C02F; C02F5/00; C02F5/08; B; B01; B01D; B01D61/00; B01D61/02; B01D61/10; B01D65/00; B01D65/02; B01D2321/00; B01D2321/16; B01D2321/162; B01D2321/168
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
93 words
A composition for cleaning solid surfaces in reverse osmosis water purification systems which are fouled with inorganic scale, comprising a 0.1 to 5 percent by weight water solution of a composition consisting essentially of (a) at least one of a monobasic alkali metal or ammonium phosphate; (b) at least one of a dibasic alkali metal or ammonium phosphate; (c) an effective amount of at least one of citric acid, malic acid, or sulfamic acid; and (d) an effective amount of a low-foaming nonionic detergent, and having a pH of from 2 to 4.
Claim 2
Dependent Claim
93 words
A composition for cleaning solid surfaces in reverse osmosis water purification systems which are fouled with inorganic scale, comprising a 0.1 to 5 percent by weight water solution of a composition consisting essentially of (a) at least one of a monobasic alkali metal or ammonium phosphate; (b) at least one of a dibasic alkali metal or ammonium phosphate; (c) an effective amount of at least one of citric acid, malic acid, or sulfamic acid; and (d) an effective amount of a low-foaming nonionic detergent, and having a pH of from 2 to 4.
Claim 3
Dependent Claim
69 words
A composition as claimed in claim 1, wherein said last mentioned composition comprises, in percent by weight: ______________________________________
monobasic sodium, potassium or ammonium phosphate
10-40%
dibasic sodium, potassium or ammonium phosphate
10-40%
citric acid 0-60%
malic acid 0-60%
a low foaming nonionic detergent
0.1-5%
______________________________________ provided that at least one of said citric and malic acids must be present, the combined amount of said acids being at least 20%.
Claim 4
Dependent Claim
15 words
A composition as claimed in claim 2, wherein said detergent is polyoxyethylene (12) tridecyl ether.
Claim 5
Dependent Claim
44 words
A composition as claimed in claim 3, wherein said last mentioned composition comprises, in percent by weight: ______________________________________
monobasic sodium, potassium or ammonium phosphate
29.0%
dibasic sodium, potassium or ammonium phosphate
15.2%
citric acid 30.5%
malic acid 24.5%
polyoxyethylene (12) tridecyl ether
0.8%
______________________________________
Claim 6
Dependent Claim
30 words
A composition as claimed in claim 2, which is effective for dissolving iron scale, wherein said last mentioned composition further comprises from 5 to 30 percent by weight oxalic acid.
Claim 7
Dependent Claim
47 words
A composition as claimed in claim 5, wherein said last mentioned composition comprises, in percent by weight: ______________________________________
monobasic sodium, potassium or ammonium phosphate
19.9%
dibasic sodium, potassium or ammonium phosphate
21.0%
citric acid 25.5%
malic acid 21.3%
oxalic acid 11.7%
polyoxyethylene (12) tridecyl ether
0.7%.
______________________________________
Claim 8
Dependent Claim
28 words
A composition as claimed in claim 1, 2, 3, 4, 5, or 6, wherein the concentration is about 2 percent and the pH is from 2 to 3.
Claim 9
Dependent Claim
50 words
A composition for cleaning solid surfaces in reverse osmosis water purifications systems which are fouled with inorganic scale comprising, in percent by weight: ______________________________________
monobasic sodium, potassium or ammonium phosphate
29.0%
dibasic sodium, potassium or ammonium phosphate
15.2%
citric acid 30.5%
malic acid 24.5%
polyoxyethylene (12) tridecyl ether
0.8%
______________________________________
Claim 10
Dependent Claim
50 words
A composition for cleaning solid surfaces in reverse osmosis water purifications systems which are fouled with inorganic scale comprising, in percent by weight: ______________________________________
monobasic sodium, potassium or ammonium phosphate
29.0%
dibasic sodium, potassium or ammonium phosphate
15.2%
citric acid 30.5%
malic acid 24.5%
polyoxyethylene (12) tridecyl ether
0.8%
______________________________________
Claim 11
Dependent Claim
53 words
A composition for cleaning solid surfaces in reverse osmosis water purification systems which are fouled with inorganic scale comprising in percent by weight: ______________________________________
monobasic sodium, potassium or ammonium phosphate
19.9%
dibasic sodium, potassium or ammonium phosphate
21.0%
citric acid 25.5%
malic acid 21.3%
oxalic acid 11.7%
polyoxyethylene (12) tridecyl ether
0.7%
______________________________________
Claim 12
Dependent Claim
53 words
A composition for cleaning solid surfaces in reverse osmosis water purification systems which are fouled with inorganic scale comprising in percent by weight: ______________________________________
monobasic sodium, potassium or ammonium phosphate
19.9%
dibasic sodium, potassium or ammonium phosphate
21.0%
citric acid 25.5%
malic acid 21.3%
oxalic acid 11.7%
polyoxyethylene (12) tridecyl ether
0.7%
______________________________________
References Cited (Backward Citations)
US27662A
Cited
US2934503A
Cited
US2878188A
Cited
US2994664A
Cited
US3211659A
Cited
US3397149A
Cited
USRE27662E
Cited
US3909437A
Cited
US4014804A
Cited
US4100100A
Cited
DE2855822A1
Cited
US4199469A
Cited
US4384900A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-01-29 | 1988-07-30 | 1989-01-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-01-29 | 1992-07-30 | 1993-01-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-01-29 | 1996-07-30 | 1997-01-29 | $7700.00 | Window Closed / Lapsed |