Preparation of Treatment Composition and System and Method of Maintaining a Treatment Bath Formed Therefrom

Abstract

Disclosed is a method of making a treatment composition. A lithium cation and carbon dioxide are combined in an aqueous medium to form the treatment composition comprising lithium carbonate in situ. Also disclosed is a system and method for maintaining a treatment bath formed from a treatment composition comprising lithium carbonate. Carbon dioxide and/or a lithium salt are supplied to the bath in an amount sufficient to maintain the pH of the treatment bath at 9.5 to 12.5, lithium in an amount of 5 ppm to 5,500 ppm (calculated as lithium cation) and carbonate in an amount of 15 ppm to 25,000 ppm (calculated as carbonate) based on total weight of the treatment bath. Substrates treated with the composition, system and method also are disclosed.

We claim: 
     
         1 . A composition comprising lithium carbonate, wherein the lithium carbonate is formed in situ by reacting a carbon dioxide source and a lithium cation in an aqueous medium. 
     
     
         2 . The composition of  claim 1 , wherein the carbon dioxide source comprises a gas, a solid, or combinations thereof. 
     
     
         3 . The composition of  claim 1 , wherein the lithium cation is present in an amount of 5 ppm to 5500 ppm (calculated as lithium cation) based on total weight of the composition. 
     
     
         4 . The composition of  claim 1 , wherein the pH is 9.5 to 12.5. 
     
     
         5 . The composition of  claim 1 , further comprising a hydroxide source. 
     
     
         6 . The composition of  claim 1 , wherein the carbonate is present in an amount of 15 ppm to 25000 ppm (calculated as carbonate) based on total weight of the treatment composition. 
     
     
         7 . A substrate treated with the composition of  claim 1 . 
     
     
         8 . A method of making a treatment composition comprising:
 combining a lithium cation and a carbon dioxide source in an aqueous medium to form the treatment composition wherein the treatment composition comprises lithium cation in an amount of 5 ppm to 5500 ppm (calculated lithium cation) based on total weight of the treatment composition and carbonate in an amount of 15 ppm to 25000 ppm (calculated as carbonate) based on total weight of the treatment composition.   
     
     
         9 . The method of  claim 8 , wherein the pH of the treatment composition is 9.5 to 12.5. 
     
     
         10 . The method of  claim 8 , further comprising adding an acid other than carbon dioxide to the treatment composition. 
     
     
         11 . The method of  claim 8 , wherein the lithium cation is present as a salt comprising lithium carbonate, lithium hydroxide, or combinations thereof. 
     
     
         12 . The method of  claim 8 , further comprising adding a hydroxide source to the aqueous medium. 
     
     
         13 . The method of  claim 8 , wherein the hydroxide source comprises lithium hydroxide, sodium hydroxide, potassium hydroxide, or combinations thereof. 
     
     
         14 . The method of  claim 8 , wherein the carbon dioxide source comprises a gas, a solid, or combinations thereof. 
     
     
         15 . A substrate treated with the method of  claim 8 . 
     
     
         16 . A system for maintaining carbonate levels in a treatment bath containing a treatment composition, comprising:
 a lithium cation; and/or   a carbon dioxide source; and   optionally, a hydroxide source.   
     
     
         17 . The system of  claim 16 , wherein the lithium cation comprises lithium carbonate, lithium hydroxide, or combinations thereof. 
     
     
         18 . The system of  claim 16 , wherein the carbon dioxide source comprises a gas, a solid, or combinations thereof. 
     
     
         19 . The system of  claim 16 , wherein the hydroxide source comprises lithium hydroxide, sodium hydroxide, potassium hydroxide, or combinations thereof. 
     
     
         20 . A substrate treated with the treatment composition in the bath maintained according to the system of  claim 16 . 
     
     
         21 . A method for maintaining carbonate levels in a treatment bath containing a treatment composition, comprising:
 supplying at least one of a carbon dioxide source and a lithium source to the bath in an amount sufficient to maintain the pH of the treatment composition at 9.5 to 12.5, lithium in an amount of 5 ppm to 5500 ppm (calculated as lithium cation) based on total weight of the treatment composition, and carbonate in an amount of 15 ppm to 25000 ppm (calculated as carbonate) based on total weight of the treatment composition.   
     
     
         22 . The method of  claim 21 , wherein the carbon dioxide source comprises a gas, a solid, or combinations thereof. 
     
     
         23 . The method of  claim 21 , wherein the lithium source comprises lithium carbonate, lithium hydroxide, or combinations thereof. 
     
     
         24 . The method of  claim 21 , further comprising supplying to the bath a hydroxide source. 
     
     
         25 . The method of  claim 21 , wherein the amount of lithium carbonate in the treatment bath following the supplying is 25 ppm to 30000 ppm (calculated as total compound) based on total weight of the treatment composition. 
     
     
         26 . The method of  claim 21 , further comprising monitoring pH of the treatment bath, amount of carbonate in the treatment bath, amount of lithium in the treatment bath, or combinations thereof. 
     
     
         27 . The method of  claim 21 , further comprising adding an acid other than carbon dioxide to the treatment bath. 
     
     
         28 . A substrate treated with the treatment composition in the bath maintained according to the method of  claim 21 .