US4357254A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Cleaning composition
Assignee: TEXAS INVESTMENT Corp 654 NORTH BELT EAST SUITE 400 HOUSTON TEX A CORP OF DE
•
Filing: 1981-01-12
•
Granted: 1982-11-02
•
Expires: 2001-01-12
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
2026-11-01 17:48
CPC Classifications
C; C11; C11D; C11D3/00; C11D3/16; C11D3/20; C11D3/2075; B; B01; B01D; B01D61/00; B01D61/02; B01D61/10; B01D65/00; B01D65/02; C02; C02F; C02F5/00; C02F5/08; C11D3/02; C11D3/04; C11D3/06; B01D2321/00; B01D2321/16; B01D2321/162; B01D2321/168
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
67 words
A composition for cleaning solid surfaces which are fouled with inorganic scale, comprising a member of the group consisting of monobasic sodium phosphate and monobasic potassium phosphate, a member of the group consisting of dibasic sodium phosphate and dibasic potassium phosphate, an effective amount of at least one member of the group consisting of citric acid and malic acid, and an effective amount of non-foaming nonionic detergent.
Claim 2
Dependent Claim
67 words
A composition for cleaning solid surfaces which are fouled with inorganic scale, comprising a member of the group consisting of monobasic sodium phosphate and monobasic potassium phosphate, a member of the group consisting of dibasic sodium phosphate and dibasic potassium phosphate, an effective amount of at least one member of the group consisting of citric acid and malic acid, and an effective amount of non-foaming nonionic detergent.
Claim 3
Dependent Claim
62 words
A composition as claimed in claim 1, for cleaning reverse osmosis water purification systems, wherein the proportions of said monobasic sodium or potassium phosphate and said dibasic sodium or potassium phosphate are such that when said composition is dissolved in water at a concentration of from about 0.1 to about 5 percent by weight, the pH will be from 2 to 4.
Claim 4
Dependent Claim
62 words
A composition as claimed in claim 2, comprising, in percent by weight: ______________________________________
monobasic sodium or potassium phosphate
10-40%
dibasic sodium or potassium 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 5
Dependent Claim
15 words
A composition as claimed in claim 3, wherein said detergent is polyoxyethylene (12) tridecyl ether.
Claim 6
Dependent Claim
37 words
A composition as claimed in claim 4, comprising, in percent by weight: ______________________________________
monobasic sodium or potassium phosphate
29%
dibasic sodium or potassium phosphate
15.2%
citric acid 30.5%
malic acid 24.5%
polyoxyethylene (12) tridecyl ether
0.8%
______________________________________
Claim 7
Dependent Claim
25 words
A composition as claimed in claim 3, which is effective for dissolving iron scale, further comprising from 5 to 30 percent by weight oxalic acid.
Claim 8
Dependent Claim
40 words
A composition as claimed in claim 6, comprising, in percent by weight: ______________________________________
monobasic sodium or potassium phosphate
19.9%
dibasic sodium or potassium phosphate
21%
citric acid 26.5%
malic acid 21.3%
oxalic acid 11.7%
polyoxyethylene (12) tridecyl ether
0.7%
______________________________________
Claim 9
Dependent Claim
39 words
A composition for cleaning fouled reverse osmosis systems comprising a 0.1 to 5 percent by weight water solution of the composition of claim 2, 3, 4, 5, 6, or 7 and having a pH of from 2 to 4.
Claim 10
Dependent Claim
22 words
A composition as claimed in claim 8, wherein the concentration is about 2 percent and the pH is from 2 to 3.
References Cited (Backward Citations)
US4049467A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-11-01 | 1986-05-03 | 1986-11-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-11-01 | 1990-05-03 | 1990-11-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-11-01 | 1994-05-03 | 1994-11-02 | $7700.00 | Window Closed / Lapsed |