US1719167A - Cleaning of metals, etc. - Google Patents
Cleaning of metals, etc. Download PDFInfo
- Publication number
- US1719167A US1719167A US160526A US16052627A US1719167A US 1719167 A US1719167 A US 1719167A US 160526 A US160526 A US 160526A US 16052627 A US16052627 A US 16052627A US 1719167 A US1719167 A US 1719167A
- Authority
- US
- United States
- Prior art keywords
- acid
- pickling
- bath
- cleaning
- condensation product
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 238000004140 cleaning Methods 0.000 title description 29
- 239000002184 metal Substances 0.000 title description 28
- 229910052751 metal Inorganic materials 0.000 title description 28
- 150000002739 metals Chemical class 0.000 title description 10
- 239000002253 acid Substances 0.000 description 52
- 238000005554 pickling Methods 0.000 description 38
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 description 32
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 22
- 239000007859 condensation product Substances 0.000 description 22
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 18
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 17
- 229910000831 Steel Inorganic materials 0.000 description 12
- 239000010959 steel Substances 0.000 description 12
- 229910052742 iron Inorganic materials 0.000 description 11
- QJGQUHMNIGDVPM-UHFFFAOYSA-N nitrogen group Chemical group [N] QJGQUHMNIGDVPM-UHFFFAOYSA-N 0.000 description 10
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 9
- 239000001257 hydrogen Substances 0.000 description 9
- 229910052739 hydrogen Inorganic materials 0.000 description 9
- 229910021529 ammonia Inorganic materials 0.000 description 8
- 150000002576 ketones Chemical class 0.000 description 8
- 230000015572 biosynthetic process Effects 0.000 description 7
- 239000003517 fume Substances 0.000 description 7
- 230000002452 interceptive effect Effects 0.000 description 7
- 238000004519 manufacturing process Methods 0.000 description 7
- 230000002401 inhibitory effect Effects 0.000 description 6
- 229910052500 inorganic mineral Inorganic materials 0.000 description 6
- 238000000034 method Methods 0.000 description 6
- 239000011707 mineral Substances 0.000 description 6
- 235000010755 mineral Nutrition 0.000 description 6
- 230000001590 oxidative effect Effects 0.000 description 6
- 239000000126 substance Substances 0.000 description 6
- 239000000047 product Substances 0.000 description 5
- BAUYGSIQEAFULO-UHFFFAOYSA-L iron(2+) sulfate (anhydrous) Chemical compound [Fe+2].[O-]S([O-])(=O)=O BAUYGSIQEAFULO-UHFFFAOYSA-L 0.000 description 3
- 239000003795 chemical substances by application Substances 0.000 description 2
- 150000001875 compounds Chemical class 0.000 description 2
- 238000009833 condensation Methods 0.000 description 2
- 230000005494 condensation Effects 0.000 description 2
- 239000011790 ferrous sulphate Substances 0.000 description 2
- 235000003891 ferrous sulphate Nutrition 0.000 description 2
- 229910000359 iron(II) sulfate Inorganic materials 0.000 description 2
- UXVMQQNJUSDDNG-UHFFFAOYSA-L Calcium chloride Chemical compound [Cl-].[Cl-].[Ca+2] UXVMQQNJUSDDNG-UHFFFAOYSA-L 0.000 description 1
- AVXURJPOCDRRFD-UHFFFAOYSA-N Hydroxylamine Chemical compound ON AVXURJPOCDRRFD-UHFFFAOYSA-N 0.000 description 1
- 241001446467 Mama Species 0.000 description 1
- QAOWNCQODCNURD-UHFFFAOYSA-L Sulfate Chemical compound [O-]S([O-])(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-L 0.000 description 1
- 150000007513 acids Chemical class 0.000 description 1
- 239000001110 calcium chloride Substances 0.000 description 1
- 229910001628 calcium chloride Inorganic materials 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000004821 distillation Methods 0.000 description 1
- BCDGQXUMWHRQCB-UHFFFAOYSA-N glycine methyl ketone Natural products CC(=O)CN BCDGQXUMWHRQCB-UHFFFAOYSA-N 0.000 description 1
- 229910000358 iron sulfate Inorganic materials 0.000 description 1
- JEIPFZHSYJVQDO-UHFFFAOYSA-N iron(III) oxide Inorganic materials O=[Fe]O[Fe]=O JEIPFZHSYJVQDO-UHFFFAOYSA-N 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000003595 mist Substances 0.000 description 1
- 235000021110 pickles Nutrition 0.000 description 1
- 239000011541 reaction mixture Substances 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 229920006395 saturated elastomer Polymers 0.000 description 1
- 239000000725 suspension Substances 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23G—CLEANING OR DE-GREASING OF METALLIC MATERIAL BY CHEMICAL METHODS OTHER THAN ELECTROLYSIS
- C23G1/00—Cleaning or pickling metallic material with solutions or molten salts
- C23G1/02—Cleaning or pickling metallic material with solutions or molten salts with acid solutions
- C23G1/04—Cleaning or pickling metallic material with solutions or molten salts with acid solutions using inhibitors
- C23G1/06—Cleaning or pickling metallic material with solutions or molten salts with acid solutions using inhibitors organic inhibitors
- C23G1/061—Cleaning or pickling metallic material with solutions or molten salts with acid solutions using inhibitors organic inhibitors nitrogen-containing compounds
Definitions
- This invention relates to the pickling and cleaning of metals, and particularly to the pickling of iron or steel, to remove scale therefrom, although the invention is of more or less general application to the cleaning or pickling of metals such as iron or steel for the removal of oxides or scale therefrom.
- the pickling or cleaning of iron or steel is commonly effected by means of acid pickling or cleaning baths which dissolve the scale or oxide from the metal.
- the pickl ng baths commonly employed are acid baths which often attack the metal as well as the scale. This action on the metal is undesirable and objectionable, involving not only excessive consumption of acids, but also corrosion or dissolving of metal and tending to give a rough or pitted surface.
- the present invention provides an improved bath for pickling or cleaning iron or steel and also an improved process of pickling or cleaning the metal in which the acid pickling bath has incorporated therein a small amount of a condensation product of a nitrogenous base with a ketone.
- condensation prod iict s' o f iiiti'figiious bases with acetone are particularly advantageous such as tl e conv densationproduct of acetgllsawltlh, amnio'ni'a.
- a suitable method of making thecon'densation product of acetone with ammonia is to introduce ammonia gas into acetone containing powdered calcium chloride in suspension until the acetone is saturated, and then allowing the reaction mixture to stand until the reaction is completed.
- the resulting oily product can be freed from excess acetone and ammonia by distillation, and can be further treated to separate the different acetone amine products or fractions therefrom.
- tion products of other nitrogenous bases and ketones may be formed in a similar manner, using other nitrogenous bases and ketones as starting products.
- the acid pickling baths with which the agents mentioned are used may be acid baths such as are commonly employed for pickling or cleaning iron and steel, containing for example, about 10% of sulfuric acid. Such baths are gradually impoverished by the action of the acid in removing the scale or rust and their content of ferrous sulfate increases until the bath becomes too weak or too concentrated in ferrous sulfate for further use.
- acid baths can be used, including acid sulfate baths.
- the amount of the condensation product added to the bath for carrying out the pickling or cleaning operation can be varied. In general, only a small amount of the condensation product is required, for example,
- the condensation product of acetone with ammonia for example, about two pounds of the condensation product can be employed so for each ton of 60 degreeacid used in the pickling bath.
- the condensation product employed should be one which is stable and does not decompose to any objectionable extent in the acid bath.
- the carrying out of the pickling or cleanmg operation may be the same as in ordinary practice.
- the pickling can be carried out continuously by passing the material to be pickled, such as wire or sheets, 0 through a number of baths in a regulated manner; or by immersing the article to be pickled "lhthe pickling bath for a suitable period of time.
- the temperature of the bath can be varied, ordinarily being around 150 or 180 F.
- the pickling bath may be replenished by the addition of further amounts of acid until the iron sulfate reaches too great a concentration.
- the addition of the condensation product to the bath prevents or retards or inhibits the action of the acid bath on the metal without interfering with the removal of scaleor oxide.
- the formation of hydrogen by the action of the acid bath on the metal is also reduced and the evolution of acid mist or fumes also great- 5 ly reduced.
- the reduced amount of action of the acid on the metal and the reduction in amount of hydrogen produced correspondingly reduces the amount of hydrogen absorbed by the metal.
- cording to the present invention involves but small additional expense and results in advantages in operation, economy of acid, protection of the metal from attack, etc., which materially improve the pickling and cleaning cleaning bath and inhibiting the chemical action of the acid on the metal without interfering with the removal of scale or oxide, and
- the method of cleaning or pickling metals which comprises subjecting the same to a non-oxidizing mineral acid pickling or cleaning bath and inhibiting the chemical action of the acid on the metal without interfering with the removal ofscale or oxide, and thereby reducing the formation of hydrogen and the production of acid fumes and effecting an economy in the acid consumed, by incorporating in the acid bath a small amount of a condensation product of acetone with a compound of the formula NH R.
- the method of cleaning or pickling metals which comprises subjecting the same to a non-oxidizing mineral acid pickling or cleaning bath and inhibiting the chemical action of the acid on the metal without interfering with the removal of scale or oxide, and thereby reducing the formation of hydrogen and the production of acid fumes and effecting an economy in the acid consumed,
- the method of pickling or cleaning iron or steel which comprises subjecting the same to an acid pickling bath containing sulfuric acid and inhibiting the chemical action of the acid on the metal without interfering with the removal of scale or oxide, and thereby reducing the formation of hydrogen and the production of acid fumes and effecting an economy in the acid consumed, by incorporating in the acid bath a small fraction of one percent of a condensation product of a nitrogenous base with a ketone.
- the method of pickling or cleaning iron or steel which comprises subjecting the same to an acid pickling bath containing sulfuric acid and inhibiting the chemical action of the acid on the metal without. interfering with. the removal of scale or oxide, and thereby reducing the formation of hydrogen and the production of acid fumes and effecting an economy in the acid consumed, by incorporating in the acid bath a small fraction of one percent of a condensation product of acetone with a compound having the formula NH R.
- the method of pickling or cleaning iron or steel which comprises subjecting the same to an acid pickling bath containing sulfuric acid and inhibiting the chemical action of the acid on the metal without interfering with the removal of scale or oxide, and thereby reducing the formation of hydrogen and the production of acid fumes and efiecting an 8 economy in the acid consumed, by incorporating in the acid bath a small fraction of one percent of a condensation product of acetone with ammonia.
- a non-oxidizing mineral acid bath for pickling or cleaning metals which contains a small amount of a condensation product of a nitrogenous base with a ketone.
- a non-oxidizing mineral acid bath for pickling or cleaning metals which contains a fraction of one percent of a condensation product of acetone with a nitrogeneous base.
- a bath for pickling or cleaning iron or steel which comprises sulfuric acid and a small amount of a condensation product of duct of acetone with a nitrogenous base.
- a bath for pickling or cleaning 11011 or steel which comprises sulfuric acid and a fraction of one percent of a condensation product of acetone with ammonia.
- a bath for pickling or cleaning iron or steel which comprises sulfuric acid and a condensation product of a nitrogenous base with a ketone.
- a bath for pickling or cleaning iron or steel which comprises sulfuric acid and a condensation product of acetone with ammonia.
- a non-oxidizing mineral acid bath for pickling or cleaning metals which contains a condensation product of acetone with a nitrogenous base.
- a non-oxidizing mineral acid bath for t pickling or cleaning metals which contains a condensation product. of acetone with ammonia.
Landscapes
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Cleaning And De-Greasing Of Metallic Materials By Chemical Methods (AREA)
Description
*UUIVIIUSI I IUNS,
o -n tre c i.
mama July 2, 1929 UNITED STATES Examiner 1,719,167 PATENT OFFICE.
GEORGE D. CHAMBERLAIN, OF ASHLAND, KENTUCKY, ASSIGNOR TO B. '1. VANDER- IBILT COMPANY, INCORPORATED, OF NEW YORK, N. Y., A CORPORATION OF NEW YORK.
CLEANING OF METALS, ETC.
R Drawing. Application filed January 11 This invention relates to the pickling and cleaning of metals, and particularly to the pickling of iron or steel, to remove scale therefrom, although the invention is of more or less general application to the cleaning or pickling of metals such as iron or steel for the removal of oxides or scale therefrom.
The pickling or cleaning of iron or steel is commonly effected by means of acid pickling or cleaning baths which dissolve the scale or oxide from the metal. The pickl ng baths commonly employed are acid baths which often attack the metal as well as the scale. This action on the metal is undesirable and objectionable, involving not only excessive consumption of acids, but also corrosion or dissolving of metal and tending to give a rough or pitted surface.
The present invention provides an improved bath for pickling or cleaning iron or steel and also an improved process of pickling or cleaning the metal in which the acid pickling bath has incorporated therein a small amount of a condensation product of a nitrogenous base with a ketone.
I have found that the addition of a small amount of a suitable condensation product of a nitrogenous base with a ketone prevents or retards or inhibits the attack of the acid pickling bath on the metal Withoutinterfering with the removal of scale or oxide by the acid bath.
The agents which are added to the cleaning or pickling bath, according to the present inaaleatinn; inelndavadeu .serdsrs t e xrre ib a scs vfith iketonesl' -Amnngthesemefbe -qafiiiij i.is9eqgis i nrcdn. t ..otr iqesl asq n b s c a mmonia.and.. rials.slliifi sllis i fiii hydroxyl amine. Certain condensation prod iict s' o f iiiti'figiious bases with acetone are particularly advantageous such as tl e conv densationproduct of acetgllsawltlh, amnio'ni'a.
A suitable method of making thecon'densation product of acetone with ammonia is to introduce ammonia gas into acetone containing powdered calcium chloride in suspension until the acetone is saturated, and then allowing the reaction mixture to stand until the reaction is completed. The resulting oily product can be freed from excess acetone and ammonia by distillation, and can be further treated to separate the different acetone amine products or fractions therefrom. Condensa- 1927. Serial No. 160,526.
tion products of other nitrogenous bases and ketones may be formed in a similar manner, using other nitrogenous bases and ketones as starting products.
The acid pickling baths with which the agents mentioned are used may be acid baths such as are commonly employed for pickling or cleaning iron and steel, containing for example, about 10% of sulfuric acid. Such baths are gradually impoverished by the action of the acid in removing the scale or rust and their content of ferrous sulfate increases until the bath becomes too weak or too concentrated in ferrous sulfate for further use. Instead of using sulfuric acid baths, other acid baths can be used, including acid sulfate baths.
The amount of the condensation product added to the bath for carrying out the pickling or cleaning operation can be varied. In general, only a small amount of the condensation product is required, for example,
a small fraction of one percent. In the case of the condensation product of acetone with ammonia, for example, about two pounds of the condensation product can be employed so for each ton of 60 degreeacid used in the pickling bath. The condensation product employed should be one which is stable and does not decompose to any objectionable extent in the acid bath. The carrying out of the pickling or cleanmg operation may be the same as in ordinary practice. For example, the pickling can be carried out continuously by passing the material to be pickled, such as wire or sheets, 0 through a number of baths in a regulated manner; or by immersing the article to be pickled "lhthe pickling bath for a suitable period of time. The temperature of the bath can be varied, ordinarily being around 150 or 180 F. The pickling bath may be replenished by the addition of further amounts of acid until the iron sulfate reaches too great a concentration. a
The addition of the condensation product to the bath prevents or retards or inhibits the action of the acid bath on the metal without interfering with the removal of scaleor oxide. The formation of hydrogen by the action of the acid bath on the metal is also reduced and the evolution of acid mist or fumes also great- 5 ly reduced. There is also a saving in the acid as well as a protection of the metal. The reduced amount of action of the acid on the metal and the reduction in amount of hydrogen produced correspondingly reduces the amount of hydrogen absorbed by the metal.
The employment of the condensation prodnot in the pickling or cleaning operation, ac-
cording to the present invention, involves but small additional expense and results in advantages in operation, economy of acid, protection of the metal from attack, etc., which materially improve the pickling and cleaning cleaning bath and inhibiting the chemical action of the acid on the metal without interfering with the removal of scale or oxide, and
thereby reducing the formation of hydrogen.
andthe production of acid fumes and effecting an economy in the acid consumed, by incorporating in the acid bath a small amount of a condensation product of a nitrogenous base with a ketone.
2. The method of cleaning or pickling metals which comprises subjecting the same to a non-oxidizing mineral acid pickling or cleaning bath and inhibiting the chemical action of the acid on the metal without interfering with the removal ofscale or oxide, and thereby reducing the formation of hydrogen and the production of acid fumes and effecting an economy in the acid consumed, by incorporating in the acid bath a small amount of a condensation product of acetone with a compound of the formula NH R.
3. The method of cleaning or pickling metals which comprises subjecting the same to a non-oxidizing mineral acid pickling or cleaning bath and inhibiting the chemical action of the acid on the metal without interfering with the removal of scale or oxide, and thereby reducing the formation of hydrogen and the production of acid fumes and effecting an economy in the acid consumed,
by incorporating in the acid bath a small amount of a condensation product of acetone with ammonia.
4. The method of pickling or cleaning iron or steel which comprises subjecting the same to an acid pickling bath containing sulfuric acid and inhibiting the chemical action of the acid on the metal without interfering with the removal of scale or oxide, and thereby reducing the formation of hydrogen and the production of acid fumes and effecting an economy in the acid consumed, by incorporating in the acid bath a small fraction of one percent of a condensation product of a nitrogenous base with a ketone.
5. The method of pickling or cleaning iron or steel which comprises subjecting the same to an acid pickling bath containing sulfuric acid and inhibiting the chemical action of the acid on the metal without. interfering with. the removal of scale or oxide, and thereby reducing the formation of hydrogen and the production of acid fumes and effecting an economy in the acid consumed, by incorporating in the acid bath a small fraction of one percent of a condensation product of acetone with a compound having the formula NH R.
6. The method of pickling or cleaning iron or steel which comprises subjecting the same to an acid pickling bath containing sulfuric acid and inhibiting the chemical action of the acid on the metal without interfering with the removal of scale or oxide, and thereby reducing the formation of hydrogen and the production of acid fumes and efiecting an 8 economy in the acid consumed, by incorporating in the acid bath a small fraction of one percent of a condensation product of acetone with ammonia.
7. A non-oxidizing mineral acid bath for pickling or cleaning metals which contains a small amount of a condensation product of a nitrogenous base with a ketone.
8. A non-oxidizing mineral acid bath for pickling or cleaning metals which contains a fraction of one percent of a condensation product of acetone with a nitrogeneous base.
9. A bath for pickling or cleaning iron or steel which comprises sulfuric acid and a small amount of a condensation product of duct of acetone with a nitrogenous base.
10. A bath for pickling or cleaning 11011 or steel which comprises sulfuric acid and a fraction of one percent of a condensation product of acetone with ammonia.
11. A bath for pickling or cleaning iron or steel which comprises sulfuric acid and a condensation product of a nitrogenous base with a ketone.
12. A bath for pickling or cleaning iron or steel which comprises sulfuric acid and a condensation product of acetone with ammonia.
13. A non-oxidizing mineral acid bath for pickling or cleaning metals which contains a condensation product of acetone with a nitrogenous base.
14. A non-oxidizing mineral acid bath for t pickling or cleaning metals which contains a condensation product. of acetone with ammonia.
In testimony whereof I aflix my signature.
1 GEORGE D. CHAMBERLAIN.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US160526A US1719167A (en) | 1927-01-11 | 1927-01-11 | Cleaning of metals, etc. |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US160526A US1719167A (en) | 1927-01-11 | 1927-01-11 | Cleaning of metals, etc. |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US1719167A true US1719167A (en) | 1929-07-02 |
Family
ID=22577246
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US160526A Expired - Lifetime US1719167A (en) | 1927-01-11 | 1927-01-11 | Cleaning of metals, etc. |
Country Status (1)
| Country | Link |
|---|---|
| US (1) | US1719167A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE1104286B (en) * | 1957-01-23 | 1961-04-06 | Swift & Co | Inhibitor for treatment baths for iron and steel |
| DE1107046B (en) * | 1957-04-06 | 1961-05-18 | Siemens Ag | Process for removing rust from objects and systems made of iron and / or steel, in particular for cleaning boiler systems and arrangement for carrying out the process |
| US3770377A (en) * | 1971-03-08 | 1973-11-06 | Celanese Corp | Process for inhibiting corrosion |
-
1927
- 1927-01-11 US US160526A patent/US1719167A/en not_active Expired - Lifetime
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE1104286B (en) * | 1957-01-23 | 1961-04-06 | Swift & Co | Inhibitor for treatment baths for iron and steel |
| DE1107046B (en) * | 1957-04-06 | 1961-05-18 | Siemens Ag | Process for removing rust from objects and systems made of iron and / or steel, in particular for cleaning boiler systems and arrangement for carrying out the process |
| US3770377A (en) * | 1971-03-08 | 1973-11-06 | Celanese Corp | Process for inhibiting corrosion |
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