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.

Claims

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: ##STR00007## 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.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0031] FIG. 1. Production of copper ammonium carbonate according to Example 2.

[0032] FIG. 2. Production of copper ammonium carbonate according to Example 3.

[0033] FIG. 3. Production of copper ammonium carbonate according to Example 4.

[0034] FIG. 4. Production of copper ammonium carbonate according to Example 5.

[0035] FIG. 5. Production of copper ammonium carbonate according to Example 6.

[0036] FIG. 6. Production of copper ammonium carbonate according to Example 7.

DETAILED DESCRIPTION OF INVENTION

[0037] The present invention provides a method for the production of a dissolved copper ammonia solution that efficiently produces the solution at an expedited rate. For purposes of this application, the copper ammonia solution is obtained by dissolving cuprous oxide that is normally insoluble in water.

[0038] Carbon dioxide may be added prior to or after the addition of the cuprous oxide to the composition to adjust the pH of the mixture to about 11.0. However the preferred addition order is prior to the addition of the cuprous oxide. The process can be run without the addition of carbon dioxide; however, the dissolution rate of the copper source is reduced significantly. Sources of carbon dioxide include but are not limited to air, carbon dioxide (g), dry ice (s)(i.e. dry ice), carbonic acid, ammonium carbonate and ammonium bicarbonate.

[0039] Any source of oxygen can be used to oxidize copper in this process. Pure oxygen, however, is preferred. Air, ozone, and hydrogen peroxide are also suitable sources of oxygen for use in this process providing standard safety precautions are taken for using oxidants in the presence of organic compounds.

[0040] The copper dissolution process could be conducted at ambient pressure. Alternatively the copper dissolution process could be conducted under pressure, such as less than 200 PSI. Preferably, the copper dissolution process could be conducted at pressures less than 100 PSI, less than 50 PSI, Less than 25 PSI and less than 10 PSI.

[0041] In certain embodiments of the invention, the quaternary ammonium compound has a chemical structure comprising:

##STR00004##

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, acetate, propionate, and other alkyl carboxylates. In certain embodiments, the value of m is at least 8 and at most 14, and the value of n is at least 8 and at most 14. In certain embodiments, the value of m is 10 or 12, the value of n is 10 or 12, the value of a is 1, the value of b is 1. In certain embodiments X− is borate, chloride, propionate, carbonate, or bicarbonate. In certain embodiments, the value of m is 10 and the value of n is 10. In certain embodiments, the value of m is 12 and the value of n is 12.

[0042] In certain embodiments of the invention, the quaternary ammonium compound has a chemical structure comprising:

##STR00005##

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.sup.− is an anion selected from the group consisting of borate, chloride, carbonate, bicarbonate, bromide, iodide, formate, acetate, propionate, acetate, propionate, and other alkyl carboxylates. In certain embodiments, the value of m is at least 8 and at most 14. In certain embodiments, the value of n is at least 8 and at most 14. In certain embodiments, the value of a is 1, the value of b is 1. In certain embodiments X.sup.− is borate, chloride, propionate, carbonate, or bicarbonate. In certain embodiments, the value of m is 10 and the value of n is 10. In certain embodiments, the value of m is 12 and the value of n is 12.

[0043] In certain embodiments of the invention, the quaternary ammonium compound has a chemical structure comprising:

##STR00006##

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.sup.− is an anion selected from the group consisting of borate, chloride, carbonate, bicarbonate, bromide, iodides, formate, acetate, propionate, and other alkyl carboxylates. In certain embodiments, the value of m, n is 10 or 12, the value of a is 1, the value of b is 1, and X.sup.− is borate, chloride, propionate, carbonate, or bicarbonate.

[0044] In a more preferred embodiment, the quaternary ammonium compound is n-alkydimethyl benzyl ammonium chloride, alkyldimethylbenzylammonium chloride, alkyldimethylbenzylammonium carbonate/bicarbonate, didecyldimethyl ammonium chloride, didecyldimethyl ammonium carbonate/bicarbonate, didodecyldimethyl ammonium chloride, didodecyldimethyl ammonium carbonate/bicarbonate, cocobis(2-hydroxyethyl) methylammonium chloride, and didecylmethylpoly(oxyethyl)ammonium propionate. The resulting dissolved copper solution can be mixed with a variety of biocides such as fungicides and insecticides to produce a formulation suitable for the preservation of wood and other cellulose-base materials. Typical biocides that can be used for this formulation are fungicides such as azoles, quaternary ammonium compounds, and various other conventional insecticides.

[0045] Another embodiment of the present invention is a method for preserving and/or waterproofing a wood substrate by contacting a wood substrate with the composition of the present invention. The composition may be applied by any wood treating method known to one of ordinary skill in the art including, but not limited to, brushing, dipping, soaking, vacuum impregnation (e.g. double vacuum technique), and pressure treatment using various cycles.

[0046] Modifications and variations of the present invention for a process for the production of aqueous copper amine solutions will be obvious to those skilled in the art from the foregoing detailed description of the invention. Such modifications and variations are intended to come within the scope of the appended claims.

EXAMPLES

[0047] The following Examples serve to further illustrate the present invention and are not to be construed as limiting its scope in any way.

Example 1

[0048] A solution mixture of 771.4 g of water and 862.0 g of aqueous ammonium hydroxide solution containing 29% ammonia was added to a beaker. The solution was mixed while a glass frit connected to a CO2 tank was submerged in the beaker and sparged into the solution. After the sparging of CO2 was complete, a charge of 181.8 g of cuprous oxide powder was added to the beaker while mixing. A separate glass frit connected to an oxygen line was submerged into the solution. Oxygen was then sparged into the solution while mixing. Solution samples were periodically taken during the reaction process to measure the copper content of the solution. After 3 hours of sparging oxygen into the solution, a solution sample was taken and analyzed for Cu. The Cu was found to be low, about 4.0%, so more oxygen was sparged into the solution to try to react the rest of the cuprous oxide. The reaction was continued for about 9 hours and the Cu content was analyzed at approximately 4.5% which was still much lower than the theoretical value of 8.0%. It was apparent much of the cuprous oxide was unreacted due to the excess buildup of material on the walls of the beaker as well as solid material present in the beaker.

Example 2

[0049] A solution mixture of 771.4 g of water and 862.0 g of aqueous ammonium hydroxide solution, containing 29% ammonia was added to a beaker. The solution was mixed while a glass frit connected to a CO2 tank was submerged in the beaker and sparged into the solution. Approximately 120.0 g of CO2 was initially added to the solution, with the remaining 40.0 g left out to be added after the reaction is complete for pH adjustment. The temperature of the solution after the addition of CO2 was at about 50° C. Before the addition of cuprous oxide, 2.65 g of antifoam and 1.0 g of alkyldimethylbenzyl ammonium chloride (ADBAC) was added to the solution while mixing. Approximately 181.8 g of cuprous oxide powder was added to the solution while mixing. Immediately after the addition of cuprous oxide, a glass frit connected to an oxygen line was submerged into the solution. The sparging of oxygen was initiated and was continued for a total of 3 hours. During the reaction, the temperature was measured at about 60° C. Solution samples were periodically taken during the reaction process to measure the copper content of the solution. After the reaction was complete at 3 hours, the glass frit connected to the CO2 tank was re-submerged in the solution and a final 38.0 g of CO2 was added.

[0050] The final Cu concentration was analyzed at about 8.31% and the reaction ran much smoother than the previous batch with no residue left on the wall of the beaker. A graph depicting the copper results throughout the reaction are shown in the appendix as FIG. 1.

Example 3

[0051] A solution mixture of 465.2 g of water and 1077.6 g of aqueous ammonium hydroxide solution, containing 29% ammonia, was added to a beaker. The solution was mixed while a glass frit connected to a CO2 tank was submerged in the beaker and sparged into the solution. Approximately 190.0 g of CO2 was then added to the solution while mixing. The temperature of the solution after the addition of CO2 was at about 60° C. Before the addition of cuprous oxide, 2.50 g of antifoam and 1.22 g of alkyldimethylbenzyl ammonium chloride was added to the solution mixing. Immediately after the addition of cuprous oxide, a glass frit connected to an oxygen line was submerged into the solution. The sparging of oxygen was initiated and was continued for approximately 3 hours. About 90 minutes into the reaction, a large amount of foam began to form in the beaker, so an additional 0.50 g of antifoam was added to the solution while mixing. Solution samples were periodically taken during the reaction process to measure the copper content of the solution.

[0052] The final Cu concentration was analyzed at about 10.24%. A graph depicting the copper results throughout the reaction are shown in the appendix as FIG. 2.

Example 4

[0053] A solution mixture of 771.4 g of water and 862.0 g of aqueous ammonium hydroxide solution, containing 29% ammonia, was added to a beaker. The solution was mixed while a glass frit connected to a CO2 tank was submerged in the beaker and sparged into the solution. Approximately 130.0 g of CO.sub.2 was initially added to the solution, with the remaining 31.0 g left out to be added after the reaction is complete for pH adjustment. Before the addition of cuprous oxide, 2.10 g of antifoam and 1.5 g of cocobis(2-hydroxyethyl) methylammonium chloride was added to the solution while mixing. Approximately 181.8 g of cuprous oxide powder was added to the solution while mixing Immediately after the addition of cuprous oxide, a glass frit connected to an oxygen line was submerged into the solution. The sparging of oxygen was initiated and was continued for approximately 3 hours. Solution samples were periodically taken during the reaction process to measure the copper content of the solution. After the reaction was complete at 3 hours, the glass frit connected to the CO.sub.2 tank was re-submerged in the solution and a final 30.0 g of CO.sub.2 was added.

[0054] The final Cu concentration was analyzed at about 8.14%. A graph depicting the copper results throughout the reaction are shown in the appendix as FIG. 3.

Example 5

[0055] A solution mixture of 612.8 g of water and 958.0 g of aqueous ammonium hydroxide solution, containing 29% ammonia, was added to a beaker. The solution was mixed while a glass frit connected to a CO.sub.2 tank was submerged in the beaker and sparged into the solution. Approximately 140.0 g of CO.sub.2 was initially added to the solution, with the remaining 30.0 g left out to be added after the reaction is complete for pH adjustment. Before the addition of cuprous oxide, 3.20 g of antifoam and 1.6 g of cocobis(2-hydroxyethyl) methylammonium chloride was added to the solution while mixing. Approximately 229.4 g of cuprous oxide was added to the solution while mixing. Immediately after the addition of cuprous oxide, a glass frit connected to an oxygen line was submerged into the solution. The sparging of oxygen was initiated and was continued for approximately 3 hours. Solution samples were periodically taken during the reaction process to measure the copper content of the solution. After the reaction was complete at 3 hours, the glass frit connected to the CO2 tank was re-submerged in the solution and a final 30.0 g of CO.sub.2 was added.

[0056] The final Cu concentration was analyzed at about 9.23%. A graph depicting the copper results throughout the reaction are shown in the appendix as FIG. 4. After a few days of static stability, a large chuck of solid formed on the bottom of the jug.

Example 6

[0057] A solution mixture of 846.56 g of water, with the remaining 164.56 g left out for final re-adjustment, and 958.0 g of aqueous ammonium hydroxide solution, containing 29% ammonia, was added to a beaker. The solution was mixed while a glass frit connected to a CO2 tank was submerged in the beaker and sparged into the solution. Approximately 150.0 g of CO2 was added to the solution, with the remaining 130.0 g left out to be added after the reaction is complete for pH adjustment. Before the addition of cuprous oxide, 3.27 g of antifoam and 2.84 g of cocobis(2-hydroxyethyl) methylammonium chloride was added to the solution while mixing. Approximately 378.6 g of cuprous oxide was added to the solution while mixing. Immediately after the addition of cuprous oxide, a glass fit connected to an oxygen line was submerged into the solution. The sparging of oxygen was initiated and was continued for approximately 3 hours. About 60 minutes into the reaction, some foam began to form in the beaker, so an additional 1.72 g of antifoam was added to the solution while mixing. Solution samples were periodically taken during the reaction process to measure the copper content of the solution.

[0058] The final Cu concentration was analyzed at about 10.41%. A graph depicting the copper results throughout the reaction are shown in the appendix as FIG. 5. After a few days of static stability, a large chuck of solid formed on the bottom of the jug.

Example 7

[0059] A solution mixture of 682.8 g of water and 960.8 g of aqueous ammonium hydroxide solution, containing 29% ammonia, was added to a beaker. The solution was mixed while a glass frit connected to a CO2 tank was submerged in the beaker and sparged into the solution. Approximately 105.0 g of CO2 was then added to the solution while mixing. Before the addition of cuprous oxide, 2.6 g of antifoam and 1.6 g of cocobis(2-hydroxyethyl) methylammonium chloride was added to the solution while mixing. Approximately 229.4 g of cuprous oxide was added to the solution while mixing. Immediately after the addition of cuprous oxide, a glass frit connected to an oxygen line was submerged into the solution. The sparging of oxygen was initiated and was continued for approximately 3 hours. About 20 minutes into the reaction, some foam began to form in the beaker, so an additional 0.4 g of antifoam was added to the solution while mixing. Solution samples were periodically taken during the reaction process to measure the copper content of the solution.

[0060] The final Cu concentration was analyzed at about 10.66%. A graph depicting the copper results throughout the reaction are shown in the appendix as FIG. 6. No solid formation appeared in the jug after a few days of static stability.