US4025359A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Inhibited acid composition for cleaning water systems
Assignee: Individual
•
Filing: 1975-07-03
•
Granted: 1977-05-24
•
Expires: 1995-07-03
Abstract
Abstract A pipe cleaning composition containing hydrochloric acid, furfural, dialkylthiourea, and water has a reduced tendency to attack galvanized pipe or steel pipe.
Inventors
- 👤 George F. Connelly, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 23:21
CPC Classifications
C; C23; C23G; C23G1/00; C23G1/02; C23G1/04; C23G1/06
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
52 words
A composition for cleaning galvanized and steel pipe which composition comprises an aqueous solution containing from about 7.5 to 25 parts by weight of hydrochloric acid, and a combination of inhibitors consisting essentially of 0.6 to 2.6 parts by weight of furfural, and 0.5 to 1.4 parts by weight of a dialkylthiourea.
Claim 2
Dependent Claim
52 words
A composition for cleaning galvanized and steel pipe which composition comprises an aqueous solution containing from about 7.5 to 25 parts by weight of hydrochloric acid, and a combination of inhibitors consisting essentially of 0.6 to 2.6 parts by weight of furfural, and 0.5 to 1.4 parts by weight of a dialkylthiourea.
Claim 3
Dependent Claim
18 words
A composition for cleaning galvanized and steel pipe as described in claim 1, wherein the dialkylthiourea is diethylthiourea.
Claim 4
Dependent Claim
39 words
A composition for cleaning galvanized and steel pipe cleaning which composition essentially consists of: ______________________________________
Parts by Weight
______________________________________
hydrochloric acid 7.5 to 25
furfural 0.6 to 2.6
dialkylthiourea 0.5 to 1.4
______________________________________ the balance consisting essentially of water.
Claim 5
Dependent Claim
39 words
A composition for cleaning galvanized and steel pipe cleaning which composition essentially consists of: ______________________________________
Parts by Weight
______________________________________
hydrochloric acid 7.5 to 25
furfural 0.6 to 2.6
dialkylthiourea 0.5 to 1.4
______________________________________ the balance consisting essentially of water.
Claim 6
Dependent Claim
18 words
A composition for cleaning galvanized and steel pipe as described in claim 3, wherein the dialkylthiourea is diethylthiourea.
Claim 7
Dependent Claim
36 words
A composition for cleaning galvanized and steel pipe as described in claim 4, which comprises: ______________________________________
Parts by Weight
______________________________________
hydrochloric acid
about 10
furfural about 1.3
diethylthiourea about 0.7
______________________________________ the balance being essentially water.
Claim 8
Dependent Claim
22 words
A composition for cleaning galvanized and steel pipe as described in claim 5, wherein the composition contains about 87.9 parts of water.
Claim 9
Independent Claim
85 words
A method of removing a scale deposit from galvanized or steel surfaces normally in contact with water, which deposit includes at least one of alkaline earth metal carbonate, which method comprises contacting said scale deposit with an aqueous composition containing from about 7.5 to 25 parts by weight of hydrochloric acid, and a combination of inhibitors consisting essentially of about 0.6 to 2.6 parts by weight of furfural, and about 0.5 to 1.4 parts by weight of dialkylthiourea, whereby said deposit is dissolved and/or dispersed.
Claim 10
Independent Claim
85 words
A method of removing a scale deposit from galvanized or steel surfaces normally in contact with water, which deposit includes at least one of alkaline earth metal carbonate, which method comprises contacting said scale deposit with an aqueous composition containing from about 7.5 to 25 parts by weight of hydrochloric acid, and a combination of inhibitors consisting essentially of about 0.6 to 2.6 parts by weight of furfural, and about 0.5 to 1.4 parts by weight of dialkylthiourea, whereby said deposit is dissolved and/or dispersed.
Claim 11
Dependent Claim
12 words
A method as described in claim 7, wherein said dialkylthiourea is diethylthiourea.
Claim 12
Dependent Claim
19 words
A method as described in claim 7, wherein said composition is continuously circulated in contact with said scale deposit.
Claim 13
Dependent Claim
12 words
A method as described in claim 9, wherein said dialkylthiourea is diethylthiourea.
Claim 14
Independent Claim
77 words
A method of inhibiting scale formation in galvanized and steel water systems which comprises adding to the water of said water system an effective scale inhibiting amount of a composition containing from about 7.5 to 25 parts by weight of hydrochloric acid, and a combination of inhibitors consisting essentially of about 0.6 to 2.6 parts by weight of furfural, and about 0.5 to 1.4 parts by weight of dialkylthiourea, and circulating said water throughout said water system.
Claim 15
Independent Claim
77 words
A method of inhibiting scale formation in galvanized and steel water systems which comprises adding to the water of said water system an effective scale inhibiting amount of a composition containing from about 7.5 to 25 parts by weight of hydrochloric acid, and a combination of inhibitors consisting essentially of about 0.6 to 2.6 parts by weight of furfural, and about 0.5 to 1.4 parts by weight of dialkylthiourea, and circulating said water throughout said water system.
Claim 16
Dependent Claim
12 words
A method as described in claim 11, wherein said dialkylthiourea is diethylthiourea.
Claim 17
Dependent Claim
15 words
A method as described in claim 11, wherein said water system is a closed system.
References Cited (Backward Citations)
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Cited
US2203649A
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US2380254A
Cited
US2959555A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-05-23 | 1980-11-22 | 1981-05-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-05-23 | 1984-11-22 | 1985-05-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-05-23 | 1988-11-22 | 1989-05-24 | $7700.00 | Window Closed / Lapsed |