US3414521A - Acid corrosion inhibitors - Google Patents
Acid corrosion inhibitors Download PDFInfo
- Publication number
- US3414521A US3414521A US482602A US48260265A US3414521A US 3414521 A US3414521 A US 3414521A US 482602 A US482602 A US 482602A US 48260265 A US48260265 A US 48260265A US 3414521 A US3414521 A US 3414521A
- Authority
- US
- United States
- Prior art keywords
- acid
- acids
- thioethylamine
- inhibitors
- weight
- 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
- 239000003112 inhibitor Substances 0.000 title description 18
- 239000002253 acid Substances 0.000 title description 16
- 230000007797 corrosion Effects 0.000 title description 11
- 238000005260 corrosion Methods 0.000 title description 10
- 229910052751 metal Inorganic materials 0.000 description 17
- 239000002184 metal Substances 0.000 description 17
- 238000000034 method Methods 0.000 description 14
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 10
- 239000011260 aqueous acid Substances 0.000 description 10
- 150000001875 compounds Chemical class 0.000 description 9
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 6
- 150000002739 metals Chemical class 0.000 description 6
- PDQAZBWRQCGBEV-UHFFFAOYSA-N Ethylenethiourea Chemical compound S=C1NCCN1 PDQAZBWRQCGBEV-UHFFFAOYSA-N 0.000 description 5
- 150000007513 acids Chemical class 0.000 description 5
- 238000004140 cleaning Methods 0.000 description 5
- 229910052742 iron Inorganic materials 0.000 description 5
- WSLDOOZREJYCGB-UHFFFAOYSA-N 1,2-Dichloroethane Chemical compound ClCCCl WSLDOOZREJYCGB-UHFFFAOYSA-N 0.000 description 4
- 229910000831 Steel Inorganic materials 0.000 description 4
- 239000007795 chemical reaction product Substances 0.000 description 4
- 239000003085 diluting agent Substances 0.000 description 4
- 229910052739 hydrogen Inorganic materials 0.000 description 4
- 125000002496 methyl group Chemical group [H]C([H])([H])* 0.000 description 4
- 238000005554 pickling Methods 0.000 description 4
- 239000010959 steel Substances 0.000 description 4
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 3
- 239000000460 chlorine Substances 0.000 description 3
- -1 ferrous metals Chemical class 0.000 description 3
- 239000001257 hydrogen Substances 0.000 description 3
- 238000007654 immersion Methods 0.000 description 3
- 150000007524 organic acids Chemical class 0.000 description 3
- 235000005985 organic acids Nutrition 0.000 description 3
- 239000000047 product Substances 0.000 description 3
- SCYULBFZEHDVBN-UHFFFAOYSA-N 1,1-Dichloroethane Chemical compound CC(Cl)Cl SCYULBFZEHDVBN-UHFFFAOYSA-N 0.000 description 2
- 229910000640 Fe alloy Inorganic materials 0.000 description 2
- OAKJQQAXSVQMHS-UHFFFAOYSA-N Hydrazine Chemical compound NN OAKJQQAXSVQMHS-UHFFFAOYSA-N 0.000 description 2
- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 description 2
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 2
- 150000003973 alkyl amines Chemical class 0.000 description 2
- 229910052799 carbon Inorganic materials 0.000 description 2
- 125000004432 carbon atom Chemical group C* 0.000 description 2
- 238000009833 condensation Methods 0.000 description 2
- 230000005494 condensation Effects 0.000 description 2
- QAWTYRYXDYHQNU-UHFFFAOYSA-N diazathiane Chemical compound NSN QAWTYRYXDYHQNU-UHFFFAOYSA-N 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 229910052736 halogen Inorganic materials 0.000 description 2
- 150000002367 halogens Chemical class 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- 125000001183 hydrocarbyl group Chemical group 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 229960003151 mercaptamine Drugs 0.000 description 2
- 229910021645 metal ion Inorganic materials 0.000 description 2
- 229910052757 nitrogen Inorganic materials 0.000 description 2
- 239000000376 reactant Substances 0.000 description 2
- 125000004434 sulfur atom Chemical group 0.000 description 2
- BRNULMACUQOKMR-UHFFFAOYSA-N thiomorpholine Chemical compound C1CSCCN1 BRNULMACUQOKMR-UHFFFAOYSA-N 0.000 description 2
- ZGZUKKMFYTUYHA-HNNXBMFYSA-N (2s)-2-amino-3-(4-phenylmethoxyphenyl)propane-1-thiol Chemical compound C1=CC(C[C@@H](CS)N)=CC=C1OCC1=CC=CC=C1 ZGZUKKMFYTUYHA-HNNXBMFYSA-N 0.000 description 1
- NDIUNRFKKUBPRJ-GORDUTHDSA-N (E)-ethylidenethiourea Chemical compound C\C=N\C(N)=S NDIUNRFKKUBPRJ-GORDUTHDSA-N 0.000 description 1
- APQIUTYORBAGEZ-UHFFFAOYSA-N 1,1-dibromoethane Chemical group CC(Br)Br APQIUTYORBAGEZ-UHFFFAOYSA-N 0.000 description 1
- DGYYJSHANXEPSK-UHFFFAOYSA-N 1-methyl-10h-phenothiazine Chemical class S1C2=CC=CC=C2NC2=C1C=CC=C2C DGYYJSHANXEPSK-UHFFFAOYSA-N 0.000 description 1
- WJFKNYWRSNBZNX-UHFFFAOYSA-N 10H-phenothiazine Chemical compound C1=CC=C2NC3=CC=CC=C3SC2=C1 WJFKNYWRSNBZNX-UHFFFAOYSA-N 0.000 description 1
- HEFKKYCXFOTNTB-UHFFFAOYSA-N 2,6-dimethylthiomorpholine Chemical compound CC1CNCC(C)S1 HEFKKYCXFOTNTB-UHFFFAOYSA-N 0.000 description 1
- ZCYVEMRRCGMTRW-UHFFFAOYSA-N 7553-56-2 Chemical group [I] ZCYVEMRRCGMTRW-UHFFFAOYSA-N 0.000 description 1
- WKBOTKDWSSQWDR-UHFFFAOYSA-N Bromine atom Chemical group [Br] WKBOTKDWSSQWDR-UHFFFAOYSA-N 0.000 description 1
- 229910020314 ClBr Inorganic materials 0.000 description 1
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- PIICEJLVQHRZGT-UHFFFAOYSA-N Ethylenediamine Chemical compound NCCN PIICEJLVQHRZGT-UHFFFAOYSA-N 0.000 description 1
- CWYNVVGOOAEACU-UHFFFAOYSA-N Fe2+ Chemical compound [Fe+2] CWYNVVGOOAEACU-UHFFFAOYSA-N 0.000 description 1
- 229910001209 Low-carbon steel Inorganic materials 0.000 description 1
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 description 1
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 description 1
- 230000002378 acidificating effect Effects 0.000 description 1
- 150000001335 aliphatic alkanes Chemical class 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 229910000147 aluminium phosphate Inorganic materials 0.000 description 1
- 125000005365 aminothiol group Chemical class 0.000 description 1
- 150000004945 aromatic hydrocarbons Chemical class 0.000 description 1
- 125000004429 atom Chemical group 0.000 description 1
- 238000009835 boiling Methods 0.000 description 1
- GDTBXPJZTBHREO-UHFFFAOYSA-N bromine Chemical group BrBr GDTBXPJZTBHREO-UHFFFAOYSA-N 0.000 description 1
- 229910052794 bromium Inorganic materials 0.000 description 1
- 230000001680 brushing effect Effects 0.000 description 1
- 229910052801 chlorine Inorganic materials 0.000 description 1
- 125000001309 chloro group Chemical group Cl* 0.000 description 1
- KRKNYBCHXYNGOX-UHFFFAOYSA-N citric acid group Chemical group C(CC(O)(C(=O)O)CC(=O)O)(=O)O KRKNYBCHXYNGOX-UHFFFAOYSA-N 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- UFULAYFCSOUIOV-UHFFFAOYSA-N cysteamine Chemical group NCCS UFULAYFCSOUIOV-UHFFFAOYSA-N 0.000 description 1
- 238000007598 dipping method Methods 0.000 description 1
- 238000004821 distillation Methods 0.000 description 1
- 239000012153 distilled water Substances 0.000 description 1
- 229910000039 hydrogen halide Inorganic materials 0.000 description 1
- 239000012433 hydrogen halide Substances 0.000 description 1
- 125000002887 hydroxy group Chemical group [H]O* 0.000 description 1
- 230000002401 inhibitory effect Effects 0.000 description 1
- 229910052500 inorganic mineral Inorganic materials 0.000 description 1
- 239000011630 iodine Chemical group 0.000 description 1
- 229910052740 iodine Chemical group 0.000 description 1
- JEIPFZHSYJVQDO-UHFFFAOYSA-N iron(III) oxide Inorganic materials O=[Fe]O[Fe]=O JEIPFZHSYJVQDO-UHFFFAOYSA-N 0.000 description 1
- VZCYOOQTPOCHFL-UPHRSURJSA-N maleic acid group Chemical group C(\C=C/C(=O)O)(=O)O VZCYOOQTPOCHFL-UPHRSURJSA-N 0.000 description 1
- 239000011707 mineral Substances 0.000 description 1
- 229910017604 nitric acid Inorganic materials 0.000 description 1
- 125000004433 nitrogen atom Chemical group N* 0.000 description 1
- 235000006408 oxalic acid Nutrition 0.000 description 1
- 150000002913 oxalic acids Chemical class 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- 229950000688 phenothiazine Drugs 0.000 description 1
- 238000010992 reflux Methods 0.000 description 1
- 150000003839 salts Chemical class 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
- 238000005507 spraying Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 125000001424 substituent group Chemical group 0.000 description 1
- 239000000758 substrate Substances 0.000 description 1
- IIACRCGMVDHOTQ-UHFFFAOYSA-N sulfamic acid group Chemical group S(N)(O)(=O)=O IIACRCGMVDHOTQ-UHFFFAOYSA-N 0.000 description 1
- 125000000446 sulfanediyl group Chemical group *S* 0.000 description 1
- 229910052717 sulfur Inorganic materials 0.000 description 1
- 239000011593 sulfur Substances 0.000 description 1
- 239000012085 test solution Substances 0.000 description 1
- RSPCKAHMRANGJZ-UHFFFAOYSA-N thiohydroxylamine Chemical compound SN RSPCKAHMRANGJZ-UHFFFAOYSA-N 0.000 description 1
- 150000003573 thiols Chemical class 0.000 description 1
- 238000011282 treatment Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 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
- C23G1/065—Cleaning or pickling metallic material with solutions or molten salts with acid solutions using inhibitors organic inhibitors sulfur-containing compounds
Definitions
- ABSTRACT OF THE DISCLOSURE is a method of pickling and cleaning a metal above hydrogen in the electromotive series in which the metal is contacted with an aqueous acid containing a small but effective amount up to 0.5 percent by weight of (1) an amino thiol or amino thioether, such compounds being further characterized by the amino nitrogen and sulfur atoms being separated from each other by divalent two carbon atom hydrocarbon groups or (2) an N,N' ethylene thiourea.
- This invention relates to a method of inhibiting corrosion of metals by acids and more particularly pertains to a method of pickling and cleaning acid corrodible metals by treating the metal with an aqueous acid containing certain thioamino compounds and thereafter removing the thioamino compound from the metal surface.
- Aqueous acids are often used in treating a variety of metals, particularly for pickling and cleaning.
- inhibitors are commonly used.
- the inhibitors which can be used are certain long chain alkyl amines which have limited solubility in aqueous acid media. These long chain alkyl amines when used on reactive metals such as iron, steel, acid reactive iron alloys, copper and aluminum, coat the metal substrate and react with dissolved polyvalent metal ions to form an objectionable scum. With iron, the reaction produced is a brown, sticky, slimy material. If not removed from the iron surface, it tends to act as a corrosion center.
- Certain sulfur-containing compounds such as thiols and thio acids, can be used as inhibitors in alkaline systems, but they suffer from 3,414,521 Patented Dec. 3, 1968 or amino thioethers in which the amino nitrogen and sulfur atoms are separated from each other by divalent two carbon atom hydrocarbon groups or an N,N' ethylene thiourea,.the corrosive effects of the aqueous acids are inhibited, the inhibitors and their reaction products are soluble in aqueous acid media, so that they leave the surface of ferrous metals clean and bright with no deposit that needs a secondary removal step. Usually, from 0.02 to about 0.2% by weight of the inhibitors suffice for protecting iron against corrosion by aqueous acids in cleaning treatments.
- Representative compounds which can be used in accordance with this invention include, but are not limited to, Z-mercaptoethyl amine, thioethylamine the product formed by reacting 1,2-dihaloethane with thioethylamine and N,N' ethylene thiourea of the structure onzonmm kiur thiomorpholine, 2,6-dimethylthiomorpholine, phenothiazinc and methyl phenothiazines in which the methyl group is on the ring.
- the dihaloethane used for reacting with thioethylamine has the structure X-CH CH X in which X represents chlorine, bromine or iodine.
- the halogens can be the same or different. Stated differently, X can be any halogen having an atom weight of at least 35.5.
- the generic formula includes (CH Cl (CH Br (CH I (CH ClBr, (CH ClI and (CH BrI.
- the thioethylamine can be reacted with any of these dihaloethanes at an elevated temperature up to 200 C. or slightly higher. With dichloroethane in the absence of a diluent the reaction becomes very vigorous when a temperature of about 85 C. is reached. For best control of the reaction, a diluent is preferred.
- the diluent can be ethylene dichloride or any inert material which boils at about C. or higher. Typical diluents are the higher alkanes or aromatic hydrocarbons.
- T he reaction itself is a condensation between the dihaloethylene and the thioethylamine by splitting ofi a hydrogen halide and proceeds according to the following formula:
- the most effective way of removing scale, rust and grime from ferrous metals is to treat the surface with an aqueous acid by spraying, dipping, brushing or wiping.
- Representative acids that are useful for this purpose include strong mineral acids such as hydrochloric acid, sulfuric acid, nitric acid and phosphoric acid, and organic acids such as acetic, hydroxy acetic, formic, citric, maleic, sulfamic and oxalic acids.
- the preferred acids are the non-oxidizing acids which include the halo-acids and organic acids mentioned above.
- the condensation can continue to provide a compound having from 1 to 3 radicals of the structure HN(CH2)2S(CH2)2N(H)0-2 and l to 4 radicals of the structure (X)u-1CH2CH7 attached to at least one nitrogen atom of the thioamine.
- the compound has terminal CH CH X groups, and if a molar excess of the thioethylamine is used, the compound has terminal groups.
- one end is usually terminated with a haloethane group and the other end of the molecule is terminated with a thioethylamine group.
- a haloethane group With equimolar amounts of reactants, one end is usually terminated with a haloethane group and the other end of the molecule is terminated with a thioethylamine group. From one to four mols of XCH CH X can be reacted with one to 3 mols of thioethylamine to obtain acid soluble products.
- the N,N' ethylidene thiourea can be made by reacting ethylenediamine with CS in alkaline media.
- the inhibitors are effective over a fairly wide range of temperatures. Against a strong acid such as HCl, the inhibitors, at a concentration of 0.1 to 0.2% by weight, protect ferrous metal up to a temperature of about 160 170 F., and with the organic acids, they are effective at temperatures of 300 F. or slightly higher. At the elevated temperatures, it is preferable to use increased amounts of inhibitor, so that above 170 F. it is most desirable to use about 0.5% or more to ensure protection of the metal against HCl attack.
- test solution was prepared by adding .1% by weight of the inhibitor to the aqueous acids listed in the table. Weighed mild steel strips 1 inch x 3 inches x A inch were immersed in 200 ml.
- a method of pickling and cleaning a metal above hydrogen in the electromotive series comprising contacting said metals with an aqueous acid containing at least a small but effective amount up to about 0.5 by weight of a corrosion inhibitor selected from the class consisting of i (a) compounds with the structure RSCH CH NH wherein R is selected from the class consisting of H, H2N-CH2CH2 and groups,
- the inhibitor is the product obtained by reacting from 1 to 4 mols of 1,2-dihaloethane with 1 to 3 mols of thioethylamine at a temperature of from about 85 to about 200 C.
- EXAMPLE 2 In this test, a strip of 1 inch x 3 inches x A inch 1010 steel was immersed in 200 ml. of 5% HCl containing .01% by weight of the reaction product obtained by heating g. of 1,2-dichloroethane with 60 g. of thioethylamine to 85 C. and allowing the reaction to continue by refluxing the boiling 1,2-dichloroethane, without additional heat. After cooling at room temperature, the unreacted 1,2-dichloroethane, about 98 g., was removed by distillation. The immersion temperature was 23 C. and
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
United States Patent 3,414,521 ACID CORROSION INHIBITORS Fred N. Teumac, Lake Jackson, Tex., assignor to The Dow Chemical Company, Midland, Mich., a corporation of Delaware No Drawing. Filed Aug. 25, 1965, Ser. No. 482,602 Claims. (Cl. 252149) ABSTRACT OF THE DISCLOSURE The invention is a method of pickling and cleaning a metal above hydrogen in the electromotive series in which the metal is contacted with an aqueous acid containing a small but effective amount up to 0.5 percent by weight of (1) an amino thiol or amino thioether, such compounds being further characterized by the amino nitrogen and sulfur atoms being separated from each other by divalent two carbon atom hydrocarbon groups or (2) an N,N' ethylene thiourea.
This invention relates to a method of inhibiting corrosion of metals by acids and more particularly pertains to a method of pickling and cleaning acid corrodible metals by treating the metal with an aqueous acid containing certain thioamino compounds and thereafter removing the thioamino compound from the metal surface.
Aqueous acids are often used in treating a variety of metals, particularly for pickling and cleaning. In order to reduce the corrosive effects of the acid on metals which are above hydrogen in the electromotive series of elements, inhibitors are commonly used. Among the inhibitors which can be used are certain long chain alkyl amines which have limited solubility in aqueous acid media. These long chain alkyl amines when used on reactive metals such as iron, steel, acid reactive iron alloys, copper and aluminum, coat the metal substrate and react with dissolved polyvalent metal ions to form an objectionable scum. With iron, the reaction produced is a brown, sticky, slimy material. If not removed from the iron surface, it tends to act as a corrosion center. If the surface of the iron or iron alloy is pitted to some degree, it is especially difficult to remove the amine-iron salt reaction product from the surface. Certain sulfur-containing compounds, such as thiols and thio acids, can be used as inhibitors in alkaline systems, but they suffer from 3,414,521 Patented Dec. 3, 1968 or amino thioethers in which the amino nitrogen and sulfur atoms are separated from each other by divalent two carbon atom hydrocarbon groups or an N,N' ethylene thiourea,.the corrosive effects of the aqueous acids are inhibited, the inhibitors and their reaction products are soluble in aqueous acid media, so that they leave the surface of ferrous metals clean and bright with no deposit that needs a secondary removal step. Usually, from 0.02 to about 0.2% by weight of the inhibitors suffice for protecting iron against corrosion by aqueous acids in cleaning treatments.
Representative compounds which can be used in accordance with this invention include, but are not limited to, Z-mercaptoethyl amine, thioethylamine the product formed by reacting 1,2-dihaloethane with thioethylamine and N,N' ethylene thiourea of the structure onzonmm kiur thiomorpholine, 2,6-dimethylthiomorpholine, phenothiazinc and methyl phenothiazines in which the methyl group is on the ring.
The dihaloethane used for reacting with thioethylamine has the structure X-CH CH X in which X represents chlorine, bromine or iodine. The halogens can be the same or different. Stated differently, X can be any halogen having an atom weight of at least 35.5. Thus, the generic formula includes (CH Cl (CH Br (CH I (CH ClBr, (CH ClI and (CH BrI.
The thioethylamine can be reacted with any of these dihaloethanes at an elevated temperature up to 200 C. or slightly higher. With dichloroethane in the absence of a diluent the reaction becomes very vigorous when a temperature of about 85 C. is reached. For best control of the reaction, a diluent is preferred. The diluent can be ethylene dichloride or any inert material which boils at about C. or higher. Typical diluents are the higher alkanes or aromatic hydrocarbons. T he reaction itself is a condensation between the dihaloethylene and the thioethylamine by splitting ofi a hydrogen halide and proceeds according to the following formula:
the drawback of very low solubility in aqueous acidic media and they react with polyvalent metalions to form insoluble salts which deposit on the surface of the metal.
The most effective way of removing scale, rust and grime from ferrous metals is to treat the surface with an aqueous acid by spraying, dipping, brushing or wiping. Representative acids that are useful for this purpose include strong mineral acids such as hydrochloric acid, sulfuric acid, nitric acid and phosphoric acid, and organic acids such as acetic, hydroxy acetic, formic, citric, maleic, sulfamic and oxalic acids. The preferred acids are the non-oxidizing acids which include the halo-acids and organic acids mentioned above.
I have found that if small but effective amounts, up to about 0.5 percent by weight of certain amino thiols The condensation can continue to provide a compound having from 1 to 3 radicals of the structure HN(CH2)2S(CH2)2N(H)0-2 and l to 4 radicals of the structure (X)u-1CH2CH7 attached to at least one nitrogen atom of the thioamine. When a molar excess of 1,2-dihaloethane is used, the compound has terminal CH CH X groups, and if a molar excess of the thioethylamine is used, the compound has terminal groups. With equimolar amounts of reactants, one end is usually terminated with a haloethane group and the other end of the molecule is terminated with a thioethylamine group. From one to four mols of XCH CH X can be reacted with one to 3 mols of thioethylamine to obtain acid soluble products.
The N,N' ethylidene thiourea can be made by reacting ethylenediamine with CS in alkaline media.
The method for preparing is described in detail in detail in my copending application Ser. No. 463,919, filed June 14, 1965 now Patent No. 3,362,996.
The inhibitors are effective over a fairly wide range of temperatures. Against a strong acid such as HCl, the inhibitors, at a concentration of 0.1 to 0.2% by weight, protect ferrous metal up to a temperature of about 160 170 F., and with the organic acids, they are effective at temperatures of 300 F. or slightly higher. At the elevated temperatures, it is preferable to use increased amounts of inhibitor, so that above 170 F. it is most desirable to use about 0.5% or more to ensure protection of the metal against HCl attack.
The examples which follow are intended to illustrate the invention, not to limit it. The parts or percentages are by weight unless otherwise indicated.
EXAMPLE 1 In each instance, the test solution was prepared by adding .1% by weight of the inhibitor to the aqueous acids listed in the table. Weighed mild steel strips 1 inch x 3 inches x A inch were immersed in 200 ml.
of the solutions at various temperatures for various periods of time. After immersion, the strips were rinsed with distilled water, dried and weighed. From the loss in weight, the corrosion rate in lbs. per sq. ft. per day were calculated.
The data obtained in these tests are tabulated below in Table I.
the duration 6 hours. This small amount of inhibitor gave protection to the steel.
I claim:
1. A method of pickling and cleaning a metal above hydrogen in the electromotive series comprising contacting said metals with an aqueous acid containing at least a small but effective amount up to about 0.5 by weight of a corrosion inhibitor selected from the class consisting of i (a) compounds with the structure RSCH CH NH wherein R is selected from the class consisting of H, H2N-CH2CH2 and groups,
(b) N,N' ethylenethiourea,
(c) the reaction product obtained by heating to a temperature of -200 C. from 1 to 4 mols of a 1,2-dihaloethane with from 1 to 3 mols of thioethylarnme,
(d) thiomorpholine and methyl substituted derivatives thereof having from 1 to 2 methyl groups on the ring, and
(e) phenothiazine and ring substituted derivatives thereof in which the substituent consists of 1 to 2 methyl groups.
2. The method of claim 1 in which the corrosion inhibitor is N,N' ethylenethiourea.
3. The method of claim 1 in which the corrosion inhibitor is thioethylamine.
4. The method of claim 1 in which the corrosion inhibitor is mercaptoethylamine.
5. The method of claim 1 in which the inhibitor is the product obtained by reacting from 1 to 4 mols of 1,2-dihaloethane with 1 to 3 mols of thioethylamine at a temperature of from about 85 to about 200 C.
6. The method of claim 1 in which the corrosion inhibitor is H NCH CH SCH CH NHCH CH NH 7. The method of claim 5 in which the dihaloethane is dichloroethane.
The steel samples after immersion were clean and bright and had no deposit on their surfaces from any of the reactants.
EXAMPLE 2 In this test, a strip of 1 inch x 3 inches x A inch 1010 steel was immersed in 200 ml. of 5% HCl containing .01% by weight of the reaction product obtained by heating g. of 1,2-dichloroethane with 60 g. of thioethylamine to 85 C. and allowing the reaction to continue by refluxing the boiling 1,2-dichloroethane, without additional heat. After cooling at room temperature, the unreacted 1,2-dichloroethane, about 98 g., was removed by distillation. The immersion temperature was 23 C. and
8. The method of claim 5 in which the dihaloethane is dibromoethane.
9. The method of claim 1 in which the acid is a nonoxidizing acid.
10. The method of claim 1 in which the acid is HCl.
References Cited UNITED STATES PATENTS 3,074,825 l/1963 Gardner 252-149 3,277,012 10/1966 Krockow 252-149 LEON D. ROSDOL, Primary Examiner. W. E. SCHULZ, Assistant Examiner.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US482602A US3414521A (en) | 1965-08-25 | 1965-08-25 | Acid corrosion inhibitors |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US482602A US3414521A (en) | 1965-08-25 | 1965-08-25 | Acid corrosion inhibitors |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US3414521A true US3414521A (en) | 1968-12-03 |
Family
ID=23916716
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US482602A Expired - Lifetime US3414521A (en) | 1965-08-25 | 1965-08-25 | Acid corrosion inhibitors |
Country Status (1)
| Country | Link |
|---|---|
| US (1) | US3414521A (en) |
Cited By (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3524719A (en) * | 1968-05-13 | 1970-08-18 | Dow Chemical Co | Synergistic mixtures of certain organic amines for retarding corrosion in aqueous systems |
| US3920392A (en) * | 1972-07-26 | 1975-11-18 | Nitto Boseki Co Ltd | Method for inhibiting corrosion of metal using polysulfone compounds |
| US3982894A (en) * | 1971-12-22 | 1976-09-28 | Petrolite Corporation | Method of inhibiting acidic corrosion of ferrous metals with polyquaternary amino polymers |
| US4332967A (en) * | 1980-06-19 | 1982-06-01 | Petrolite Corporation | Compounds containing sulfur and amino groups |
| US4393026A (en) * | 1980-06-19 | 1983-07-12 | Petrolite Corporation | Compounds containing sulfur and amino groups |
| US4450137A (en) * | 1981-11-10 | 1984-05-22 | Petrolite Corporation | Processes for inhibiting corrosion using compounds containing sulfur and amino groups |
| US4450138A (en) * | 1981-11-10 | 1984-05-22 | Petrolite Corporation | Processes for inhibiting corrosion using compounds containing sulfur and amino groups |
| US4539404A (en) * | 1980-06-19 | 1985-09-03 | Petrolite Corporation | Pyrimidines containing sulfur and amino groups as corrosion inhibitors |
| US4616085A (en) * | 1980-06-19 | 1986-10-07 | Petrolite Corporation | Thioethers of imidazolines |
| US4684507A (en) * | 1981-11-10 | 1987-08-04 | Petrolite Corporation | Process of corrosion inhibition using compounds containing sulfur and amino groups |
| US4751051A (en) * | 1981-09-14 | 1988-06-14 | Petrolite Corporation | α-aminoalkylsulfur compositions |
| US4859354A (en) * | 1985-03-12 | 1989-08-22 | Ciba-Geigy Corporation | Nitrogen-containing additives for non-aqueous functional fluids |
| US6013200A (en) * | 1997-05-13 | 2000-01-11 | Baker Hughes Incorporated | Low toxicity corrosion inhibitor |
| US20060194700A1 (en) * | 2005-02-25 | 2006-08-31 | Weatherford/Lamb | Corrosion inhibitor systems for low, moderate and high temperature fluids and methods for making and using same |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3074825A (en) * | 1962-04-03 | 1963-01-22 | Chemical Cleaning Inc | Method of removing copper-containing iron oxide incrustations from ferriferous surfaces |
| US3277012A (en) * | 1961-06-29 | 1966-10-04 | Spiess G M B H Dr | Agent for unrusting iron and ironcontaining articles |
-
1965
- 1965-08-25 US US482602A patent/US3414521A/en not_active Expired - Lifetime
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3277012A (en) * | 1961-06-29 | 1966-10-04 | Spiess G M B H Dr | Agent for unrusting iron and ironcontaining articles |
| US3074825A (en) * | 1962-04-03 | 1963-01-22 | Chemical Cleaning Inc | Method of removing copper-containing iron oxide incrustations from ferriferous surfaces |
Cited By (16)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3524719A (en) * | 1968-05-13 | 1970-08-18 | Dow Chemical Co | Synergistic mixtures of certain organic amines for retarding corrosion in aqueous systems |
| US3982894A (en) * | 1971-12-22 | 1976-09-28 | Petrolite Corporation | Method of inhibiting acidic corrosion of ferrous metals with polyquaternary amino polymers |
| US3920392A (en) * | 1972-07-26 | 1975-11-18 | Nitto Boseki Co Ltd | Method for inhibiting corrosion of metal using polysulfone compounds |
| US4616085A (en) * | 1980-06-19 | 1986-10-07 | Petrolite Corporation | Thioethers of imidazolines |
| US4393026A (en) * | 1980-06-19 | 1983-07-12 | Petrolite Corporation | Compounds containing sulfur and amino groups |
| US4539404A (en) * | 1980-06-19 | 1985-09-03 | Petrolite Corporation | Pyrimidines containing sulfur and amino groups as corrosion inhibitors |
| US4332967A (en) * | 1980-06-19 | 1982-06-01 | Petrolite Corporation | Compounds containing sulfur and amino groups |
| US4751051A (en) * | 1981-09-14 | 1988-06-14 | Petrolite Corporation | α-aminoalkylsulfur compositions |
| US4450137A (en) * | 1981-11-10 | 1984-05-22 | Petrolite Corporation | Processes for inhibiting corrosion using compounds containing sulfur and amino groups |
| US4450138A (en) * | 1981-11-10 | 1984-05-22 | Petrolite Corporation | Processes for inhibiting corrosion using compounds containing sulfur and amino groups |
| US4684507A (en) * | 1981-11-10 | 1987-08-04 | Petrolite Corporation | Process of corrosion inhibition using compounds containing sulfur and amino groups |
| US4859354A (en) * | 1985-03-12 | 1989-08-22 | Ciba-Geigy Corporation | Nitrogen-containing additives for non-aqueous functional fluids |
| US6013200A (en) * | 1997-05-13 | 2000-01-11 | Baker Hughes Incorporated | Low toxicity corrosion inhibitor |
| US20060194700A1 (en) * | 2005-02-25 | 2006-08-31 | Weatherford/Lamb | Corrosion inhibitor systems for low, moderate and high temperature fluids and methods for making and using same |
| US8563481B2 (en) * | 2005-02-25 | 2013-10-22 | Clearwater International Llc | Corrosion inhibitor systems for low, moderate and high temperature fluids and methods for making and using same |
| US9234125B2 (en) | 2005-02-25 | 2016-01-12 | Weatherford/Lamb, Inc. | Corrosion inhibitor systems for low, moderate and high temperature fluids and methods for making and using same |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US3414521A (en) | Acid corrosion inhibitors | |
| US4734259A (en) | Mixtures of α,β-unsaturated aldehides and surface active agents used as corrosion inhibitors in aqueous fluids | |
| Schmitt | Application of inhibitors for acid media: report prepared for the European federation of corrosion working party on inhibitors | |
| US4100100A (en) | Cobalt-containing inhibitor for sour gas conditioning solutions | |
| US5120471A (en) | Process and composition for protecting chrome steel | |
| US2425320A (en) | Cleaning and pickling of metals | |
| US4554090A (en) | Combination corrosion/scale inhibitor | |
| US2959555A (en) | Copper and iron containing scale removal from ferrous metal | |
| US4180469A (en) | Dithiocarbamate sulfonium salt inhibitor composition | |
| US4541946A (en) | Corrosion inhibitor for amine gas sweetening systems | |
| US5611992A (en) | Corrosion inhibitor blends with phosphate esters | |
| US3079345A (en) | Propargyl compounds as corrosion inhibitors | |
| US4640786A (en) | Phosphonium salt-containing corrosion inhibitors for high density brines | |
| US4252743A (en) | Quaternaries of halogen derivatives of alkynoxymethyl amines | |
| US4187277A (en) | Process of inhibiting corrosion with quaternaries of halogen derivatives of alkynoxymethyl amines | |
| US3197403A (en) | Acidizing corrosion inhibitor | |
| US3428566A (en) | Process of corrosion inhibition with 1-hexyn-3-ol | |
| US1773024A (en) | Process for the pickling of metals | |
| US4329475A (en) | Selected poly(oxyalkylated) 1,3,4-thiadiazoles and their use as corrosion inhibitors | |
| US3585142A (en) | Method of removing copper-containing incrustations from ferrous metal surfaces using an aqueous acid solution of aminoalkyl thiourea | |
| US3535240A (en) | Sulfoximine corrosion inhibitor for acid solutions | |
| US4840667A (en) | Metal-chelating diphenolamine oligomers for corrosion inhibition of metal substrates | |
| US3458354A (en) | Method of removing copper-containing scale from metal surfaces | |
| US3249548A (en) | Corrosion inhibiting composition comprising 4-ethyl-1-octyn-3-ol | |
| US3277104A (en) | Acid corrosion inhibiting compositions |