Method To Control Corrosion Of A Metal Surface Using Alkyl Sulfamic Acids Or Salts Thereof

Abstract

The present invention provides a method of inhibiting corrosion of a metal surface with at least one alkyl sulfamic acid or salt thereof to the metal surface in an amount effective to inhibit corrosion of the metal surface. The alkyl sulfamic acid or salt thereof can be applied in any suitable manner to the metal surface, for example, flowing, coating, sponging, wiping, spraying, painting, showering, and/or misting.

What is claimed is: 
     
         1 . A method of inhibiting corrosion of a metal surface comprising:
 applying at least one alkyl sulfamic acid or salt thereof to the metal surface in an amount effective to inhibit corrosion of the metal surface.   
     
     
         2 . The method of  claim 1 , wherein said alkyl sulfamic acid is a C 1 -C 12  alkyl sulfamic acid or salt thereof. 
     
     
         3 . The method of  claim 1 , wherein the at least one alkyl sulfamic acid has the formula R 1 R 2 NS(O) 2 (OH), and
 R 1  and R 2  are independently a hydrogen, a C 4 -C 20  alkyl group, or a cycloalkyl group, and R1 and R2 are not both hydrogen, and/or   R 1 , R 2 , and the N form a 5-8 membered heterocyclic ring including one or more of O, NH, and CH 2 .   
     
     
         4 . The method of  claim 1 , wherein R 1  and R 2  are independently a hydrogen, a C 4 -C 20  alkyl group, or a cycloalkyl group, and R 1  and R 2  are not both hydrogen. 
     
     
         5 . The method of  claim 1 , wherein R 1  or R 2 , but not both, is a C4-C 20  alkyl group or a cycloalkyl group. 
     
     
         6 . The method of  claim 1 , wherein both R 1  and R 2  are a C 4 -C 20  alkyl group or cycloalkyl group. 
     
     
         7 . The method of  claim 1 , wherein R 1 , R 2 , and the N form a 5-8 membered heterocyclic ring including one or more of O, NH, and CH 2 . 
     
     
         8 . The method of  claim 1 , wherein the alkyl sulfamic acid or salt thereof is present in a fluid applied to the metal surface. 
     
     
         9 . The method of  claim 8 , wherein the fluid is a liquid. 
     
     
         10 . The method of  claim 8 , wherein the fluid is a vapor. 
     
     
         11 . The method of  claim 8 , wherein the fluid comprises at least one of H 2 O, NH 3 , and an alcohol. 
     
     
         12 . The method of  claim 8 , wherein the fluid comprises an acid or base in addition to the alkyl sulfamic acid or salt thereof. 
     
     
         13 . The method of  claim 8 , wherein the fluid comprises a salt solution of at least one salt independent of a alkyl sulfamic acid salt. 
     
     
         14 . The method of  claim 1 , wherein the applying comprises one or more of flowing, coating, sponging, wiping, spraying, painting, showering, and misting of the at least one alkyl sulfamic acid or salt thereof. 
     
     
         15 . The method of  claim 1 , wherein the applying comprises flowing a fluid comprising the at least one alkyl sulfamic acid or salt thereof over the metal surface. 
     
     
         16 . The method of  claim 1 , wherein the metal surface is a non-ferrous surface. 
     
     
         17 . The method of  claim 1 , wherein the metal surface comprises copper or a copper-containing alloy. 
     
     
         18 . The method of  claim 1 , further comprising contacting the metal surface with at least one corrosive agent. 
     
     
         19 . The method of  claim 16 , wherein the applying is performed before, during, and/or after the contacting. 
     
     
         20 . The method of  claim 1 , wherein the metal surface is part of a closed fluid system.