Method of preparing copper-containing wood preserving compositions

Abstract

The present invention relates to a method for producing copper ammonia solutions by reacting a cuprous oxide with ammonia, carbon dioxide and an oxidant. The resulting copper-containing solution can then be used to formulate a variety of wood preserving products.

1 - 39 . (canceled) 
     
     
         40 . A method for producing a copper ammonia solution comprising:
 forming a mixture comprising:
 water; 
 cuprous oxide; 
 an ammonia containing compound, wherein the mixture comprises 5 to 25% by weight ammonia, based on the total weight of the mixture; 
 a carbon dioxide source; and 
 an oxidant; and 
   wherein the cuprous oxide reacts with the ammonia to dissolve the cuprous oxide and form a copper ammonia solution;   wherein the cuprous oxide dissolves at an average dissolution rate of at least 1% by weight copper per hour, based on the total weight of the copper ammonia solution.   
     
     
         41 . The method of  claim 40 , wherein the carbon dioxide source comprises gaseous carbon dioxide, dry ice, carbonic acid, ammonium carbonate, ammonium bicarbonate, or a combination thereof. 
     
     
         42 . The method of  claim 40 , further comprising introducing the carbon dioxide source into the mixture in an amount sufficient to maintain a pH of the mixture between 10 and 12. 
     
     
         43 . The method of  claim 40 , wherein the oxidant comprises oxygen, air, ozone, hydrogen peroxide, or a combination thereof. 
     
     
         44 . The method of  claim 40 , further comprising introducing the oxidant into the mixture at a flow rate of between 0.5 and 100 standard cubic feet per hour (SCFH). 
     
     
         45 . The method of  claim 44 , wherein the flow rate of the oxidant is between 0.5 and 5 SCFH. 
     
     
         46 . The method of  claim 40 , wherein the mixture is maintained at a temperature in a range of 20° C. and 100° C. 
     
     
         47 . The method of  claim 46 , wherein the mixture is maintained as a temperature in range of 50° C. and 60° C. 
     
     
         48 . The method of  claim 40 , wherein the mixture is maintained at a pressure of less than 200 psi. 
     
     
         49 . The method of  claim 40 , wherein the mixture further comprises 0.125% to 0.250% by weight of a quaternary ammonium compound based on the total weight of the mixture. 
     
     
         50 . The method of  claim 49 , wherein the quaternary ammonium compound has a chemical structure comprising: 
       
         
           
           
               
               
           
         
       
       wherein the value of m is at least 1 and at most 20, the value of n is at least 1 and at most 20, the value of a is at least 1 and at most 5, the value of b is at least 1 and at most 5, and X− is an anion selected from the group consisting of borate, chloride, carbonate, bicarbonate, bromide, iodide, formate, acetate, propionate, and other alkyl carboxylates. 
     
     
         51 . The method of  claim 49 , wherein the quaternary ammonium compound comprises n-alkydimethyl benzyl ammonium chloride, alkyldimethylbenzylammonium chloride, alkyldimethylbenzylammonium carbonate, alkyldimethylbenzylammonium bicarbonate, didecyldimethyl ammonium chloride, didecyldimethyl ammonium carbonate, didecyldimethyl ammonium bicarbonate, didodecyldimethyl ammonium chloride, didodecyldimethyl ammonium carbonate, didodecyldimethyl ammonium bicarbonate, cocobis(2-hydroxyethyl) methylammonium chloride, didecylmethylpoly(oxyethyl)ammonium propionatem, or a combination thereof. 
     
     
         52 . The method of  claim 49 , wherein the quaternary ammonium compound comprises (C12-C18) dimethylbenzylammonium chloride. 
     
     
         53 . The method of  claim 49 , wherein the value of m and n is 10 or 12, the value of a is 1, the value of b is 1, and X− is borate, chloride, propionate, carbonate, or bicarbonate. 
     
     
         54 . The method of  claim 40 , wherein the cuprous oxide, the water, the ammonia, the oxidant and the cationic surfactant are mixed in a single reaction chamber. 
     
     
         55 . The method of  claim 54 , wherein the single reaction chamber is columnar. 
     
     
         56 . The method of  claim 40 , wherein the cuprous oxide dissolves at an average dissolution rate of at least 0.2% by weight copper per minute based on the weight of the copper ammonia solution during the first 10 minutes of the reacting the cuprous oxide with the ammonia. 
     
     
         57 . A method for producing a copper ammonia solution comprising:
 forming a mixture comprising:
 cuprous oxide; 
 water; 
 an ammonia containing compound, wherein the mixture comprises 5 to 25% by weight ammonia based on the total weight of the mixture; and 
 0.125 and 0.250% by weight of a quaternary ammonium compound based on the total weight of the mixture; 
   introducing an oxidant to the mixture at a flow rate in a range of 0.5 and 100 standard cubic feet per hour (SCFH);   introducing a carbon dioxide source to the mixture in an amount sufficient to maintain a pH of the mixture in a range of 10 and 12; and   wherein the cuprous oxide reacts with the ammonia to produce a copper ammonia solution.   
     
     
         58 . The method of  claim 57 , wherein the carbon dioxide source comprises gaseous carbon dioxide, dry ice, carbonic acid, ammonium carbonate, ammonium bicarbonate, or a combination thereof. 
     
     
         59 . The method of  claim 57 , wherein the oxidant comprises oxygen, air, ozone, hydrogen peroxide, or a combination thereof.