Claims
- 1. A composition for cleaning scale encrusted copper, steel or galvanized metal surfaces wherein said scale includes at least one alkaline earth metal carbonate, said composition consisting essential of:
- an aqueous solution of from about 7.5 to 25 percent by weight of hydrochloric acid,
- a corrosion inhibiting amount of an inhibitor system including from about 0.05 to 5.0 percent by weight (based on the weight of the aqueous acid solution) of an amine-based inhibitor which is the reaction product of an acetylenic alcohol with a primary or a secondary amine, said amine-based inhibitor including a solubilizer selected from the group consisting of polyoxylated mono and diamines having the formulae: ##STR3## wherein R is an aliphatic hydrocarbon radical having from 8 to 22 carbon atoms and x, y and z are integers, the sum of which is from 2 to 50, and;
- an effective amount of a polydimethylsiloxane anti-foam agent, said siloxane having a viscosity of about 100 centistokes at 25.degree. C.
- 2. A composition as described in claim 1 wherein the amine-based inhibitor is the reaction product of from 1 to 4 moles of the acetylenic alcohol containing from 3 to 10 carbon atoms with one mole of an amine selected from the group consisting of primary and secondary amine having the formulae:
- RNH.sub.2
- and
- RR'NH
- and substituted polymethylene diamines having the formula:
- RNH(CH.sub.2).sub.x NH.sub.2
- wherein, in all instances, R and R' are hydrocarbon radicals containing from 8 to 22 carbon atoms, and x is an integer of from 2 to 6.
- 3. A composition as described in claim 1 wherein said polydimethylsiloxane anti-foam agent comprises finely divided silica.
- 4. A composition as described in claim 1 which consists essentially of:
- ______________________________________ Parts By Weight______________________________________hydrochloric acid about 10amine-based inhibitor (includingsolubilizer) about 1.0polysiloxane anti-foam agent about 1.0______________________________________
- the balance being essentially water.
- 5. A composition as described in claim 1 consisting essentially of:
- ______________________________________ Parts by Weight______________________________________hydrochloric acid 7.5 to 25amine-based inhibitor (includingsolubilizer) 0.05 to 2.5furfural 0.6 to 2.5dialkylthiourea wherein the alkylgroups contain up to about 4carbon atoms 0.5 to 1.4benzylthiocyanate 0.0 to 2.0polysiloxane anti-foam agent in an amount equal tofrom 5% to 120% by weight of the amine-based in-hibitor;______________________________________
- the balance consisting essentially of water.
- 6. A composition as described in claim 5 wherein components are present in the following approximate proportions by volume:
- ______________________________________hydrochloric acid about 10amine-based inhibitor (includingsolubilizer) about 0.3furfural about 0.6diethylthiourea about 0.6polysiloxane anti-foam agent about 0.05______________________________________
- the balance being essentially water.
- 7. A method of removing scale deposit from galvanized, steel or copper surfaces normally in contact with water, which deposit includes at least one alkaline earth metal carbonate, which method comprises contacting said scale deposit with an aqueous composition as described in claim 5, whereby said deposit is dissolved and/or dispersed.
- 8. A composition as described in claim 1 which consists essentially of:
- ______________________________________ Parts By Weight______________________________________hydrochloric acid 7.5 to 25amine-based inhibitor (includingsolubilizer) 0.2 to 5.0polysiloxane anti-foam agent 0.01 to 3.0______________________________________
- the balance consisting essentially of water.
- 9. A composition as described in claim 8 wherein the amount of anti-foam agent is from about 10 to about 120% of the weight of said amine-based inhibitor.
- 10. A method of removing scale deposit from galvanized, steel or copper surfaces normally in contact with water, which deposit includes at least one alkaline earth metal carbonate, which method comprises contacting said scale deposit with an aqueous composition as claimed in claim 9, whereby said deposit is dissolved and/or dispersed.
Parent Case Info
The present invention is a continuation-in-part of copending application Ser. No. 799,282 filed May 23, 1977 now abandoned, which in turn is a continuation in part of Ser. No. 593,037 filed July 3, 1975, now U.S. Pat. No. 4,025,359, which in turn is a continuation-in-part of application Ser. No. 456,468 filed Apr. 1, 1974, now U.S. Pat. No. 3,969,255.
US Referenced Citations (5)
Non-Patent Literature Citations (1)
Entry |
G. E. Silicones "Silicone Antifoams" prior-1969 pp. 8, 9. |
Continuation in Parts (3)
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Number |
Date |
Country |
Parent |
799282 |
May 1977 |
|
Parent |
593037 |
Jul 1975 |
|
Parent |
456468 |
Apr 1974 |
|