Method of preparing metal-containing wood preserving compositions

Abstract

The present invention relates to a method for producing metal-containing amine solutions by reacting a metal or metal-containing compound, in particular, copper or a copper-containing compound, with an amine, carbon dioxide and an oxidizing agent. The resulting metal-amine solution can then be used to formulate a variety of metal-based wood preserving products.

1 . A method for dissolving copper or a copper-containing material comprising the steps of mixing copper or a copper-containing material, water, amine, carbon dioxide in an amount less than about 5% by weight, and an oxidant such that the aqueous solution contains between about 5 and about 12% dissolved copper within 5 hours.  
   
   
       2 . The method of  claim 1 , wherein the aqueous solution contains between about 5 and 12% dissolved copper within 3 hours.  
   
   
       3 . The method of  claim 1 , wherein the aqueous solution contains between about 5 and about 12% dissolved copper within 1 hour.  
   
   
       4 . The method of  claim 1 , wherein the aqueous solution further comprises a surfactant.  
   
   
       5 . The method of  claim 4 , wherein the surfactant is (C 12 -C 18 ) dimethylbenzylammonium chloride.  
   
   
       6 . A method for dissolving copper or a copper-containing material comprising the steps of mixing the copper or a copper-containing material, water, amine, carbon dioxide, and an oxidant such that the aqueous solution contains between about 5 and about 12% dissolved copper within 5 hours.  
   
   
       7 . The method of  claim 6 , wherein the aqueous solution contains between about 5 and 12% dissolved copper within 3 hours.  
   
   
       8 . The method of  claim 6 , wherein the aqueous solution contains between about 5 and 12% dissolved copper within 1 hour.  
   
   
       9 . A method for dissolving copper or a copper-containing material comprising the steps of mixing the copper or a copper-containing material, water, an amine, and carbon dioxide, and introducing an oxidant to the solution at an air at flow rate of between about 0.5 and 100 standard cubic feet per hour (SCFH).  
   
   
       10 . The method of  claim 9 , wherein the air flow rate is between about 0.5 and 5 SCFH.  
   
   
       11 . The method of  claim 9 , wherein the aqueous solution contains between about 5 and 12% dissolved copper within 5 hours.  
   
   
       12 . The method of  claim 11 , wherein the aqueous solution contains between about 5 and 12% dissolved copper within 3 hours.  
   
   
       13 . The method of  claim 12 , wherein the aqueous solution contains between about 5 and 12% dissolved copper within 1 hour.  
   
   
       14 . A method for dissolving copper or a copper-containing material comprising the steps of mixing the copper or a copper-containing material, water, amine, carbon dioxide, an oxidant and an and a quaternary ammonium change to surfactant then cationic surfactant compound in an amount sufficient to produce a rate at least twice that observed in the absence of the quaternary ammonium compound.  
   
   
       15 . The method of  claim 14 , wherein the solution contains between about 5 and about 12% dissolved copper within 5 hours.  
   
   
       16 . The method of  claim 14 , wherein the aqueous solution contains between about 5 and 12% dissolved copper within 3 hours.  
   
   
       17 . The method of  claim 14 , wherein the aqueous solution contains between about 5 and 12% dissolved copper within 1 hour.  
   
   
       18 . The method of  claim 14 , wherein the quaternary ammonium compound is present in an amount between 0.125 and 0.250% by weight.  
   
   
       19 . The method of  claim 1 , wherein the copper or a copper-containing material, water, amine and the oxidant are mixed in a single reaction chamber.  
   
   
       20 . The method of  claim 19 , wherein the single reaction chamber is columnar.  
   
   
       21 . The method of  claim 1 , wherein the water, amine and the oxidant are mixed in one reaction chamber and the resulting solution is circulated through copper or a copper-containing material in a second reaction chamber.  
   
   
       22 . A method for dissolving copper comprising the steps of mixing the copper, water, between about 40 and about 50% monoethanolamine, carbon dioxide in an amount less than about 5% by weight, an oxidant and a quaternary ammonium compound such that the aqueous solution contains between about 5 and about 12% dissolved copper within 5 hours.  
   
   
       23 . The method of  claim 22 , wherein the water, amine and the oxidant are mixed in one reaction chamber and the resulting solution is circulated through copper or a copper-containing material in a second reaction chamber.  
   
   
       24 . The method of  claim 22 , wherein the wherein the carbon dioxide is added to the solution after addition of the copper.  
   
   
       25 . A method for producing a metal amine solution, comprising the steps of: mixing a water-insoluble metal or metal-containing material, water, an amine, an oxidizing agent and a surfactant in a concentration sufficient to produce a metal-amine solution at a rate at least 1.5-fold that observed in the absence of the surfactant.  
   
   
       26 . The method of  claim 25 , wherein the surfactant is in a concentration sufficient to produce a metal-amine solution at a rate at least 2-fold that observed in the absence of the surfactant.  
   
   
       27 . The method of  claim 25 , wherein the surfactant is in a concentration sufficient to produce a metal-amine solution at a rate at least 5-fold that observed in the absence of the surfactant.  
   
   
       28 . The method of  claim 25 , wherein the surfactant is in a concentration sufficient to produce a metal-amine solution at a rate at least 10-fold that observed in the absence of the surfactant.  
   
   
       29 . The method of  claim 25 , wherein the surfactant is in a concentration sufficient to produce a metal-amine solution at a rate at least 50% greater than that observed in the absence of the surfactant.  
   
   
       30 . The method of  claim 25 , wherein the metal-containing material is a copper-containing material.  
   
   
       31 . The method of  claim 30 , wherein the copper-containing material is cuprous oxide.  
   
   
       32 . The method of  claim 25 , wherein the metal is a copper.  
   
   
       33 . The method of  claim 25 , wherein the amine is selected from the group consisting of any compound that has the following chemical structure:  
     
       
         
         
             
             
         
       
     
     wherein R1, R2, R3, R4, R5, R6 is independently selected from the group consisting of H,-CH 3 ,—C 2 H 5 ; —C 2 H 4 OH  
   
   
       34 . The method of  claim 33 , wherein the amine is monoethanolamine, diethanolamine, ethylamine, diethylamine, dimethylethylamine, dimethylethanolamine, or mixtures thereof.  
   
   
       35 . The method of  claim 34 , wherein the amine is monoethanolamine.  
   
   
       36 . The method of  claim 25 , wherein the surfactant is non-ionic.  
   
   
       37 . The method of  claim 25 , wherein the surfactant is anionic.  
   
   
       38 . The method of  claim 25 , wherein the surfactant is cationic.  
   
   
       39 . The method of  claim 38 , wherein the cationic surfactant is a quaternary ammonium compound.  
   
   
       40 . The method of  claim 39 , wherein the quaternary ammonium compound has the following structure:  
     
       
         
         
             
             
         
       
     
     wherein R 1 , R 2 , R 3 , and R4 are independently selected from alkyl or aryl groups and X − selected from chloride, bromide, iodide, carbonate, bicarbonate, borate, carboxylate, hydroxide, sulfate, acetate, laurate, or any other anionic group.  
   
   
       41 . The method of  claim 39 , wherein the quaternary ammonium compound is n− alkydimethyl benzyl ammonium chloride, alkyldimethylbenzylammonium chloride, alkyldimethylbenzylammonium carbonate/bicarbonate, dimethyldidecylammonium chloride, didecyl dimethyl ammonium chloride, or dimethyldidecylammonium carbonate/bicarbonate.  
   
   
       42 . The method of  claim 39 , wherein the quaternary ammonium compound is (C 12 -C 18 ) dimethylbenzylammonium chloride.  
   
   
       43 . The method of  claim 25  further comprising a defoaming agent.  
   
   
       44 . The method of  claim 43 , wherein the defoaming agent is a silicon polymer.  
   
   
       45 . The method of  claim 44 , wherein the silicon polymer is polyoxylalkylene silicon.  
   
   
       46 . The method of  claim 25 , wherein the surfactant is a low-foaming surfactant.  
   
   
       47 . The method of  claim 39 , wherein the quaternary ammonium compound is low foaming.  
   
   
       48 . The method of  claim 25 , wherein the oxidizing agent is oxygen, air, ozone, or hydrogen peroxide.  
   
   
       49 . The method of  claim 25 , further comprising the step of heating the solution to between 30 and  100° C.    
   
   
       50 . The method of  claim 25 , wherein temperature is maintained between about 50° and  100° C.    
   
   
       51 . The method of  claim 25 , wherein temperature is maintained between about 50° and  70° C.    
   
   
       52 . The method of  claim 25 , wherein the solution contains between about 20 and about 60% amine.  
   
   
       53 . The method of  claim 52 , wherein the solution contains between about 30 and about 50% amine.  
   
   
       54 . The method of  claim 52 , wherein the solution contains between about 40 and about 50% amine.  
   
   
       55 . The method of  claim 25 , wherein the oxidant is introduced to the aqueous solution at a flow rate of between about 0.5 and 10 SCFH.  
   
   
       56 . The method of  claim 25 , wherein the oxidant is introduced to the aqueous solution at a flow rate of between about 0.5 and 5 SCFH.  
   
   
       57 . The method of  claim 25 , further comprising the step of adding an acid to the solution.  
   
   
       58 . The method of  claim 57 , wherein the acid is carbon dioxide.  
   
   
       59 . The method of  claim 57 , wherein the acid is added to the solution prior to addition of the metal or metal-containing material.  
   
   
       60 . The method of  claim 57 , wherein the acid is added to the solution after addition of the metal or metal-containing material.  
   
   
       61 . The method of  claim 57 , wherein the solution comprises less than about 5% acid by weight.  
   
   
       62 . The method of  claim 25 , wherein the pH of the aqueous solution is initially between about 9.5 and 11.5.  
   
   
       63 . The method of  claim 62 , wherein the pH of the aqueous solution is initially between about 10.5 and 11.5.  
   
   
       64 . The method of claim, 25, wherein the pH of the aqueous solution is maintained between about 10 and 12 .  
   
   
       65 . The method of  claim 64 , wherein the acid is carbon dioxide.  
   
   
       66 . The method of  claim 25 , wherein the aqueous solution further comprises an anti-foaming agent.  
   
   
       67 . The method of  claim 25 , further comprising the step of stirring the solution.  
   
   
       68 . The method of  claim 25 , further comprising the step of circulating the solution.  
   
   
       69 . The method of  claim 25 , wherein the solution contains between about 5 and about 12% dissolved copper within 5 hours.  
   
   
       70 . The method of  claim 25 , wherein the aqueous solution contains between about 5 and 12% dissolved copper within 3 hours.  
   
   
       71 . The method of  claim 25 , wherein the aqueous solution contains between about 5 and about 12% dissolved copper within 1 hour.  
   
   
       72 . The method of  claim 25 , wherein the method is conducted at pressure greater than 1 atmosphere.