Metal oxides dispersant composition

Abstract

This invention relates to metal oxides dispersant compositions comprising (a) certain a metal oxides dispersant, and (b) an oxime. The invention also relates to a process for dispersing metal oxides in an aqueous system that involves adding the dispersant composition to the aqueous system.

We claim:  
     
         1 . A metal oxides dispersant composition for aqueous systems comprising: 
 (a) a metal oxides dispersant selected from the group consisting of (1) polymers with multiple functionalities and (2) inorganic dispersants; and    (b) an effective amount of an oxime which enhances the dispersion efficacy of (a).    
     
     
         2 . The composition of  claim 1  wherein the metal oxides dispersant is a polymer having multiple functionalities selected from the group consisting of polymers derived from more than one monomer.  
     
     
         3 . The composition of  claim 2  wherein the polymer having multiple functionalities has an anionic, nonionic, or anionic/nonionic functionality.  
     
     
         4 . The composition of  claim 1  wherein the metal oxides dispersant is a polymer having multiple functionalities has two or more functionalities selected from the group consisting of anionic, nonionic, or anionic/nonionic functionality.  
     
     
         5 . The composition of  claim 2  wherein the metal oxides dispersant is a water-soluble, hydrolyzed or partially hydrolyzed, acrylamides/acrylates copolymer polymer having anionic functionality.  
     
     
         6 . The composition of  claim 2  wherein the metal oxides is a sulfonated styrene/maleic anhydride copolymer having anionic functionality.  
     
     
         7 . The composition of  claim 4  wherein the metal oxides dispersant is a phosphonated nonionic alkyl polymer.  
     
     
         8 . The composition of  claim 4  wherein the metal oxides dispersant is a phosphino carboxylate.  
     
     
         9 . The composition of  claim 1  wherein the metal oxides dispersant is selected from the group consisting of phosphonates, polyphosphates, and orthophosphate.  
     
     
         10 . The composition of claims  1 ,  2 ,  3 ,  4 ,  5 ,  6 ,  7 ,  8 , or  9  wherein the oxime is methyl ethyl ketoxime.  
     
     
         11 . The composition of  claim 10  wherein the weight ratio of (a) to (b) is from 0.5:1 to 20:1.  
     
     
         12 . The composition of  claim 11  wherein the weight ratio of (a) to (b) is from 0.5:1.0 to 5:1.  
     
     
         13 . A process for inhibiting corrosion deposits from metal surfaces in contact with an aqueous system comprising: 
 adding a metal oxides dispersant composition to said aqueous system where said metal oxides dispersant comprises: 
 (a) a metal oxides dispersant selected from the group consisting of (1) selected from the group consisting of polymers with multiple functionalities and (2) inorganic dispersants; and  
 (b) an effective amount of an oxime which enhances the dispersion efficacy of (a).  
   whereby (a) and (b) can be added separately at the same location or independent locations or as a mixture to said aqueous system.    
     
     
         14 . The process of  claim 13  wherein the metal oxides dispersant is a polymer having multiple functionalities selected from the group consisting of polymers derived from more than one monomer.  
     
     
         15 . The process of  claim 14  wherein the polymer having multiple functionalities has an anionic, nonionic, or anionic/nonionic functionality.  
     
     
         16 . The process of  claim 13  wherein the metal oxides dispersant is a polymer having multiple functionalities has two or more functionalities selected from the group consisting of anionic, nonionic, or anionic/nonionic functionality.  
     
     
         17 . The process of  claim 14  wherein the metal oxides dispersant is a water-soluble, hydrolyzed or partially hydrolyzed, acrylamides/acrylates copolymer polymer having anionic functionality.  
     
     
         18 . The process of  claim 14  wherein the metal oxides is a sulfonated styrene/maleic anhydride copolymer having anionic functionality.  
     
     
         19 . The process of  claim 16  wherein the metal oxides dispersant is a phosphonated nonionic alkyl polymer.  
     
     
         20 . The process of  claim 16  wherein the metal oxides dispersant is a phosphino carboxylate.  
     
     
         21 . The process of  claim 14  wherein the metal oxides dispersant is selected from the group consisting of phosphonates, polyphosphates, and orthophosphate.  
     
     
         22 . The process of claims  14 ,  15 ,  16 ,  17 ,  18 ,  19 ,  20 , or  21  wherein the oxime is methyl ethyl ketoxime.  
     
     
         23 . The process of  claim 22  wherein the weight ratio of (a) to (b) is from 0.5:1 to 20:1.  
     
     
         24 . The process of  claim 23  wherein the weight ratio of (a) to (b) is from 0.5:1.0 to 5:1. 
 The process of  claim 11  wherein the metal oxides dispersant is selected from the group consisting of polymers nonionic polymers, polymers having an anionic functionality, nonionic polymers having an anionic functional group.  
 
     
     
         25 . The process of  claim 24  wherein the steam generator residual of the dispersant is from 1 to 100 ppm.  
     
     
         26 . The process of  claim 25  wherein the steam generator residual of the dispersant is from 2 to 50 ppm.  
     
     
         27 . The process of  claim 26  wherein the steam generator residual of the dispersant is from 5 to 25 ppm.  
     
     
         28 . The process of  claim 27  wherein the oxime is added to a feedpoint which will expose the said methyl ethyl ketoxime to a temperature of at least 65° C.  
     
     
         29 . The process of  claim 28  wherein the metal surface is heat exchange metal surface of a steam generating system  
     
     
         30 . The process of  claim 29  wherein the dispersant composition is added separately at the same location or independent locations or as a mixture to said aqueous system.