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US4033896A Expired / Lapsed US ⏱️ 0.0 years remaining

Method of corrosion inhibition and compositions therefor

Assignee: Monsanto Co
•
Filing: 1976-06-18
•
Granted: 1977-07-05
•
Expires: 1996-06-18
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Abstract

Abstract Phosphonomethyl amino carboxylates of the general formula <IMAGE> wherein M1, M2 and M3 are each hydrogen, metal ion, ammonium ion or alkyl ammonium ion, Z is -CH2PO3M1M2, C1-4 alkanol, C1-4 alkyl carboxylic acid, or C1-10 alkaminomethylene phosphonic acid radical, and Q is C3-15 alkylene, C3-15 alkenylene, or alkaryl radical are useful alone or in combination with one or more conventional corrosion inhibitor compounds to inhibit the corrosion of metals in aqueous systems.

Inventors

  • 👤 Robert S. Mitchell
  • 👤 Thomas M. King

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-01 19:04
CPC Classifications
C; C23; C23F; C23F11/00; C23F11/08; C23F11/10; C23F11/167; C23F11/1676

Claims Analysis

Total Claims: 38
Claim 1
Independent Claim 111 words
A method of inhibiting the corrosion of metals in a water system comprising maintaining in the water of said system at least 1 part per million of phosphonomethyl amino carboxylate having the general formula ##STR4## wherein M 1 , M 2 and M 3 are individually selected from the group consisting of hydrogen, metal ions, ammonium ions, and alkyl ammonium ions containing up to about 10 carbon atoms; Z is --CH 2 PO 3 M 1 M 2 , C 1-4 alkanol, C 1-4 alkyl carboxylic acid or C 1-10 alkaminomethylene phosphonic acid; and Q is selected from the group consisting of C 3-15 alkylene, C 3-15 alkenylene, and alkaryl radicals.
Claim 2
Independent Claim 111 words
A method of inhibiting the corrosion of metals in a water system comprising maintaining in the water of said system at least 1 part per million of phosphonomethyl amino carboxylate having the general formula ##STR4## wherein M 1 , M 2 and M 3 are individually selected from the group consisting of hydrogen, metal ions, ammonium ions, and alkyl ammonium ions containing up to about 10 carbon atoms; Z is --CH 2 PO 3 M 1 M 2 , C 1-4 alkanol, C 1-4 alkyl carboxylic acid or C 1-10 alkaminomethylene phosphonic acid; and Q is selected from the group consisting of C 3-15 alkylene, C 3-15 alkenylene, and alkaryl radicals.
Claim 3
Dependent Claim 17 words
The method of claim 1 wherein M 1 , M 2 and M 3 are each hydrogen.
Claim 4
Dependent Claim 22 words
The method of claim 1 wherein M 1 , M 2 and M 3 are each an alkali metal ion or hydrogen.
Claim 5
Dependent Claim 21 words
The method of claim 1 wherein M 1 , M 2 and M 3 are each an ammonium ion or hydrogen.
Claim 6
Dependent Claim 13 words
The method of claim 1 wherein Q is a C 3-6 alkylene radical.
Claim 7
Dependent Claim 29 words
The method of claim 1 wherein the water of said system additionally contains from about 1 to about 100 ppm of a zinc compound soluble in said water system.
Claim 8
Dependent Claim 23 words
The method of claim 1 wherein the water of said system additionally contains a compound of hexavalent chromium soluble in said water system.
Claim 9
Dependent Claim 44 words
The method of claim 1 wherein the water of said system additionally contains from about 1 to about 100 ppm of a water-soluble compound of hexavalent chromium and from about 1 to about 100 ppm of a zinc compound soluble in said water system.
Claim 10
Dependent Claim 34 words
The method of claim 1 wherein the water of said system additionally contains a compound selected from the group consisting of 1,2,3-triazoles, thiols of thiazoles, thiols of oxazoles, thiols of imidazoles and mixtures thereof.
Claim 11
Dependent Claim 17 words
The method of claim 1 wherein Z is --CH 2 PO 3 M 1 M 2 .
Claim 12
Dependent Claim 15 words
The method of claim 1 wherein the said compound is bis(phosphonomethyl) amino propylene carboxylic acid.
Claim 13
Dependent Claim 15 words
The method of claim 1 wherein the said compound is bis(phosphonomethyl) amino pentamethylene carboxylic acid.
Claim 14
Dependent Claim 14 words
The method of claim 1 wherein the said compound is bis(phosphonomethyl) amino benzyl-4-carboxylic acid.
Claim 15
Dependent Claim 16 words
The method of claim 8 wherein the said carboxylate compound is bis(phosphonomethyl) amino pentamethylene carboxylic acid.
Claim 16
Dependent Claim 16 words
The method of claim 9 wherein the said carboxylate compound is bis(phosphonomethyl) amino pentamethylene carboxylic acid.
Claim 17
Dependent Claim 16 words
The method of claim 11 wherein the said compound is the disodium salt of said acid.
Claim 18
Dependent Claim 16 words
The method of claim 12 wherein the said compound is the disodium salt of said acid.
Claim 19
Dependent Claim 23 words
The method of claim 9 wherein the water system additionally contains from about 1 to about 100 ppm of a water-soluble zinc salt.
Claim 20
Dependent Claim 16 words
The method of claim 1 wherein the metal in the water system comprises a ferrous metal.
Claim 21
Dependent Claim 31 words
The method of claim 1 wherein the water system additionally contains a water soluble polymer selected from the group consisting of polyacrylates, polyamides, partially hydrolyzed polyacrylamides, sulfonated polyacrylates and sulfonated polyacrylamides.
Claim 22
Dependent Claim 14 words
The method of claim 1 wherein the water system additionally contains an inorganic phosphate.
Claim 23
Dependent Claim 22 words
The method of claim 1 wherein the water system additionally contains from about 1 to about 100 ppm of a water-soluble silicate.
Claim 24
Independent Claim 47 words
The method of inhibiting corrosion of ferrous metals in a water system comprising maintaining in the water of said system from about 3 to about 150 ppm of a phosphonomethyl amino carboxylate having the formula (H.sub.2 O.sub.3 PCH.sub.2).sub.2 -- N-- (CH.sub.2).sub.3-6 -- COOH or its water-soluble salts.
Claim 25
Independent Claim 47 words
The method of inhibiting corrosion of ferrous metals in a water system comprising maintaining in the water of said system from about 3 to about 150 ppm of a phosphonomethyl amino carboxylate having the formula (H.sub.2 O.sub.3 PCH.sub.2).sub.2 -- N-- (CH.sub.2).sub.3-6 -- COOH or its water-soluble salts.
Claim 26
Dependent Claim 114 words
A composition comprising from about 10 percent to about 80 percent by weight of a water-soluble zinc salt and from about 20 percent to 90 percent by weight of a phosphonomethyl amino carboxylate having the general formula ##STR5## wherein M 1 , M 2 and M 3 are individually selected from the group consisting of hydrogen, metal ions, ammonium ions, and alkyl ammonium ions containing up to about 10 carbon atoms; Z is --CH 2 PO 3 M 1 M 2 , C 1-4 alkanol, C 1-4 alkyl carboxylic acid or C 1-10 alkaminomethylene phosphonic acid; and Q is selected from the group consisting of C 3-15 alkylene, C 3-15 alkenylene and alkaryl radicals.
Claim 27
Dependent Claim 114 words
A composition comprising from about 10 percent to about 80 percent by weight of a water-soluble zinc salt and from about 20 percent to 90 percent by weight of a phosphonomethyl amino carboxylate having the general formula ##STR5## wherein M 1 , M 2 and M 3 are individually selected from the group consisting of hydrogen, metal ions, ammonium ions, and alkyl ammonium ions containing up to about 10 carbon atoms; Z is --CH 2 PO 3 M 1 M 2 , C 1-4 alkanol, C 1-4 alkyl carboxylic acid or C 1-10 alkaminomethylene phosphonic acid; and Q is selected from the group consisting of C 3-15 alkylene, C 3-15 alkenylene and alkaryl radicals.
Claim 28
Dependent Claim 17 words
A composition of claim 24 wherein M 1 , M 2 and M 3 are each hydrogen.
Claim 29
Dependent Claim 23 words
A composition of claim 24 wherein at least one of M 1 , M 2 and M 3 is an alkali metal ion.
Claim 30
Dependent Claim 21 words
A composition of claim 24 wherein at least one of M 1 , M 2 and M 3 is ammonium ion.
Claim 31
Dependent Claim 25 words
A composition of claim 24 wherein the water-soluble zinc salt is zinc sulfate and at least one of M 1 and M 2 is sodium.
Claim 32
Dependent Claim 26 words
A composition of claim 24 additionally containing from 1 percent to about 60 percent by weight of said carboxylate of a water-soluble hexavalent compound of chromium.
Claim 33
Dependent Claim 21 words
A composition of claim 24 wherein the phosphonomethyl amino carboxylate has the formula (H.sub.2 O.sub.3 PCH.sub.2).sub.2 -- N-- (CH.sub.2).sub.5 -- COOH.
Claim 34
Dependent Claim 27 words
A composition of claim 30 wherein the zinc salt is zinc sulfate, and the ratio of zinc ion to phosphonomethyl amino carboxylate is from 1:1 to 3:1.
Claim 35
Dependent Claim 16 words
A composition of claim 24 wherein the phosphonomethyl amino carboxylate is bis(phosphonomethyl) amino propylene carboxylic acid.
Claim 36
Dependent Claim 15 words
A composition of claim 24 wherein the phosphonomethyl amino carboxylate is bis(phosphonomethyl) amino benzyl-4-carboxylic acid.
Claim 37
Dependent Claim 41 words
A composition of claim 24 additionally containing from 1 percent to about 10 percent by weight of said carboxylate of a compound selected from the group consisting of 1,2,3-triazoles, thiols of thiazoles, thiols of oxazoles, thiols of imidazoles, and mixtures thereof.
Claim 38
Dependent Claim 27 words
A composition of claim 34 and additionally containing from 1 percent to about 60 percent by weight of said carboxylate of a water-soluble hexavalent compound of chromium.

References Cited (Backward Citations)

US3288846A Cited
US3354215A Cited
US3298956A Cited
US3483133A Cited
US3668237A Cited
US3705005A Cited
US3969260A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1980-07-04 1981-01-03 1981-07-05 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1984-07-04 1985-01-03 1985-07-05 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1988-07-04 1989-01-03 1989-07-05 $7700.00 Window Closed / Lapsed

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