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. A method for dissolving cuprous oxide comprising: producing a reaction by mixing cuprous oxide, water, 5 to 25% by weight ammonia based on the total weight of an aqueous solution, carbon dioxide in an amount less than 15% by weight based on the total weight of the aqueous solution, an oxidant and a cationic surfactant to form the aqueous solution such that the aqueous solution contains between 5 and 12% dissolved copper within 5 hours based on the total weight of the aqueous solution, wherein the cationic surfactant comprises a quaternary ammonium compound having a chemical structure comprising: ##STR00007## ##STR00008## ##STR00009## 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, and other alkyl carboxylates.

2. The method of claim 1, wherein carbon dioxide is provided in a form of carbon dioxide, dry ice, carbonic acid, ammonium carbonate or ammonium bicarbonate.

3. The method of claim 1, wherein the aqueous solution contains between 5 and 12% dissolved copper within 3 hours.

4. The method of claim 1, wherein the aqueous solution contains between 5 and 12% dissolved copper within 1 hour.

5. The method of claim 1, wherein the quaternary ammonium compound has a chemical structure comprising: ##STR00010## wherein the value of in 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, and other alkyl carboxylates.

6. The method of claim 1, wherein the quaternary ammonium compound has a chemical structure comprising: ##STR00011## 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, and other alkyl carboxylates.

7. The method of claim 1, wherein the quaternary ammonium compound has a chemical structure comprising: ##STR00012## 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.

8. The method of claim 1, wherein 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, or didecylmethylpoly(oxyethyl)ammonium propionate.

9. The method of claim 1, wherein the quaternary ammonium compound is (C.sub.12-C.sub.18) dimethylbenzylammonium chloride.

10. The method of claim 1, wherein the mixing comprises introducing the oxidant to the solution at a flow rate of between 0.5 and 100 standard cubic feet per hour (SCFH).

11. The method of claim 10, wherein the oxidant flow rate is between 0.5 and 5 SCFH.

12. The method of claim 10, wherein the aqueous solution contains between 5 and 12% dissolved copper within 5 hours.

13. The method of claim 10, wherein the aqueous solution contains between 5 and 12% dissolved copper within 3 hours.

14. The method of claim 10, wherein the aqueous solution contains between 5 and 12% dissolved copper within 1 hour.

15. The method of claim 10, wherein said reaction is maintained between 20° C. to 95° C.

16. The method of claim 1, wherein the cationic surfactant is an amount sufficient to produce an average dissolution rate at least twice that observed in the absence of the cationic surfactant.

17. The method of claim 16, wherein the solution contains between 5 and 12% dissolved copper within 5 hours.

18. The method of claim 16, wherein the aqueous solution contains between 5 and 12% dissolved copper within 3 hours.

19. The method of claim 16, wherein the aqueous solution contains between 5 and 12% dissolved copper within 1 hour.

20. The method of claim 16, wherein the cationic surfactant is present in an amount between 0.125 and 0.250% by weight.

21. The method of claim 16, wherein the cuprous oxide, the water, the ammonia, the oxidant and the cationic surfactant are mixed in a single reaction chamber.

22. The method of claim 16, wherein the cationic surfactant is in a concentration sufficient to produce a copper solution at an average dissolution rate at least 5-fold that observed in the absence of the cationic surfactant.

23. The method of claim 16, wherein the cationic surfactant is in a concentration sufficient to produce a copper solution at an average dissolution rate at least 10-fold that observed in the absence of the cationic surfactant.

24. The method of claim 16, wherein the cationic surfactant is in a concentration sufficient to produce a copper solution at an average dissolution rate at least 50% greater than that observed in the absence of the cationic surfactant.

25. The method of claim 16, wherein the quaternary ammonium compound has a chemical structure comprising: ##STR00013## 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, and other alkyl carboxylates.

26. The method of claim 16, wherein the quaternary ammonium compound has a chemical structure comprising: ##STR00014## 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, and other alkyl carboxylates.

27. The method of claim 16, wherein the quaternary ammonium compound has a chemical structure comprising: ##STR00015## 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.

28. The method of claim 16, wherein 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, or didecylmethylpoly(oxyethyl)ammonium propionate.

29. The method of claim 16, wherein the quaternary ammonium compound is (C.sub.12-C.sub.18) dimethylbenzylammonium chloride.

30. The method of claim 16, wherein the quaternary ammonium compound is low foaming.

31. The method of claim 16, wherein said reaction is maintained between 20° C. to 95° C.

32. The method of claim 1 further comprising a defoaming agent.

33. The method of claim 32, wherein the defoaming agent is a silicon polymer.

34. The method of claim 33, wherein the silicon polymer is polyoxylalkylene silicon.

35. The method of claim 1, wherein the cationic surfactant is a low-foaming surfactant.

36. The method of claim 1, wherein the oxidant is oxygen, air, ozone, or hydrogen peroxide.

37. The method of claim 1, wherein said reaction is maintained between 20° C. to 95° C.

38. The method of claim 1, 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.sup.− is borate, chloride, propionate, carbonate, or bicarbonate.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1. Production of copper ammonium carbonate according to Example 2.

(2) FIG. 2. Production of copper ammonium carbonate according to Example 3.

(3) FIG. 3. Production of copper ammonium carbonate according to Example 4.

(4) FIG. 4. Production of copper ammonium carbonate according to Example 5.

(5) FIG. 5. Production of copper ammonium carbonate according to Example 6.

(6) FIG. 6. Production of copper ammonium carbonate according to Example 7.

DETAILED DESCRIPTION OF INVENTION

(7) 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.

(8) 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.

(9) 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.

(10) 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.

(11) In certain embodiments of the invention, the quaternary ammonium compound has a chemical structure comprising:

(12) ##STR00004##

(13) 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. 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.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.

(14) In certain embodiments of the invention, the quaternary ammonium compound has a chemical structure comprising:

(15) ##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.

(16) In certain embodiments of the invention, the quaternary ammonium compound has a chemical structure comprising:

(17) ##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.

(18) 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.

(19) 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.

(20) 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

(21) 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

(22) 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 CO.sub.2 tank was submerged in the beaker and sparged into the solution. After the sparging of CO.sub.2 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

(23) 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 CO.sub.2 tank was submerged in the beaker and sparged into the solution. Approximately 120.0 g of CO.sub.2 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 CO.sub.2 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 CO.sub.2 tank was re-submerged in the solution and a final 38.0 g of CO.sub.2 was added.

(24) 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

(25) 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 CO.sub.2 tank was submerged in the beaker and sparged into the solution. Approximately 190.0 g of CO.sub.2 was then added to the solution while mixing. The temperature of the solution after the addition of CO.sub.2 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.

(26) 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

(27) 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 CO.sub.2 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.

(28) 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

(29) 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 CO.sub.2 tank was re-submerged in the solution and a final 30.0 g of CO.sub.2 was added.

(30) 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

(31) 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 CO.sub.2 tank was submerged in the beaker and sparged into the solution. Approximately 150.0 g of CO.sub.2 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.

(32) 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

(33) 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 CO.sub.2 tank was submerged in the beaker and sparged into the solution. Approximately 105.0 g of CO.sub.2 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.

(34) 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.