Fire-retardant compositions and their uses
Disclosed are fire-retardant concentrates and solutions comprising mixtures of ammonium phosphates. In certain embodiments, less of the concentrate is needed to form an effective fire-retardant solution. In certain embodiments, the fire-retardant solutions exhibit decreased corrosion, especially with regard to magnesium. In certain embodiments, the fire-retardant solutions exhibit decreased aquatic toxicity.
1. A fire-retardant concentrate composition comprising a mixture of ammonium phosphates and a corrosion inhibitor system that comprises at least one biopolymer, wherein the mixture of ammonium phosphates has a molar ratio of ammoniacal nitrogen to phosphorus (N/P molar ratio) in a range of from 1.4 to about 1.9, and wherein when the concentrate is mixed at a ratio of from about 0.9 to about 1.3 pounds of the concentrate per 1.0 gallon of water, the resulting aqueous solution exhibits a magnesium alloy corrosion rate equal to or less than 4.0 milli-inches per year.
2. The fire-retardant concentrate composition of claim 1 , wherein the N/P molar ratio is from about 1.5 to about 1.9.
3. The fire-retardant concentrate composition of claim 1 , wherein the N/P molar ratio is from about 1.6 to about 1.9.
4. The fire-retardant concentrate composition of claim 1 , wherein the amount of ammonium phosphate in the fire-retardant concentrate is from about 75% to about 97% by weight of the total concentrate composition.
5. The fire-retardant concentrate composition of claim 1 , wherein the ammonium phosphates comprise a mixture of at least two ammonium phosphates selected from the group consisting of ammonium orthophosphates, ammonium pyrophosphates, and ammonium polyphosphates having an average chain length of less than 20 phosphorus atoms.
6. The fire-retardant concentrate composition of claim 5 , comprising at least two ammonium orthophosphates or at least two ammonium pyrophosphates.
7. The fire-retardant concentrate composition of claim 5 , comprising at least one ammonium orthophosphate and at least one ammonium pyrophosphate.
8. The fire-retardant concentrate composition of claim 1 , wherein the mixture of ammonium phosphates comprises monoammonium orthophosphate (MAP) and diammonium orthophosphate (DAP).
9. The fire-retardant concentrate composition of claim 1 , wherein the mixture of ammonium phosphates consists essentially of monoammonium phosphate (MAP) and diammonium phosphate (DAP).
10. The fire-retardant concentrate composition of claim 8 , wherein the mixture of ammonium phosphates comprises:
MAP containing from about 10% to about 12% ammoniacal nitrogen by weight and from about 40% to about 61% phosphorus pentoxide by weight; and
DAP containing from about 16% to about 21% ammoniacal nitrogen by weight and from about 40% to about 54% phosphorus pentoxide by weight.
11. The fire-retardant concentrate composition of claim 8 , wherein the weight ratio of MAP to DAP is in the range of from about 5% to about 60% MAP to about 40% to about 95% DAP of the total ammonium phosphate in the concentrate.
12. The fire-retardant concentrate composition of claim 1 , wherein the biopolymer portion of the corrosion inhibitor system is in an amount of from about 2.0% to about 8.5% by weight of the total concentrate composition.
13. The fire-retardant concentrate composition of claim 12 , wherein the biopolymer portion of the corrosion inhibitor system is in an amount of from about 2.0% to about 3.0% by weight of the total concentrate composition.
14. The fire-retardant concentrate composition of claim 1 , wherein the corrosion inhibitor system further comprises anhydrous sodium molybdate, its dihydrate, or mixtures thereof.
15. The fire-retardant concentrate composition of claim 14 , wherein the amount of anhydrous sodium molybdate, its dihydrate, or mixtures thereof is in a range of about 0.01% to about 2.0% by weight of the total concentrate composition.
16. A fire-retardant concentrate composition comprising a mixture of ammonium phosphates and a corrosion inhibitor system that comprises a biopolymer selected from the group consisting of xanthan gum, rhamsan gum, welan gum, diutan gum, and mixtures thereof, wherein the mixture of ammonium phosphates has a molar ratio of ammoniacal nitrogen to phosphorus (N/P molar ratio) in a range of from about 1.1 to about 1.9, and wherein when the concentrate is mixed at a ratio of from about 0.9 to about 1.3 pounds of the concentrate per 1.0 gallon of water, the resulting aqueous solution exhibits a magnesium alloy corrosion rate equal to or less than 4.0 milli-inches per year.
17. The fire-retardant concentrate composition of claim 16 , wherein the biopolymer is xanthan gum.
18. The fire-retardant concentrate composition of claim 16 , wherein the biopolymer is diutan gum.
19. The fire-retardant concentrate composition of claim 1 , further comprising a pigment or dye.
20. The fire-retardant concentrate composition of claim 19 , wherein the pigment or dye is a fluorescent pigment or dye.
21. The fire-retardant concentrate composition of claim 19 , wherein the pigment or dye is UV sensitive and/or formaldehyde-free.
22. The fire-retardant concentrate composition of claim 20 , wherein the fluorescent pigment or dye has a Lab color spacing of “L” in a range from about 34 to about 89, “a” in a range from about 18 to about 83 and “b” in a range from about −61 to about 56.
23. The fire-retardant concentrate composition of claim 1 , wherein the composition comprises one or more additives selected from the group consisting of a flow conditioner, a surfactant, a foam controlling additive, a foam former, a biocide, and any combination thereof.
24. The fire-retardant concentrate composition of claim 16 , wherein the N/P molar ratio is from about 1.4 to about 1.9.
25. The fire-retardant concentrate composition of claim 16 , wherein the N/P molar ratio is from about 1.5 to about 1.9.
26. The fire-retardant concentrate composition of claim 16 , wherein the N/P molar ratio is from about 1.6 to about 1.9.
27. The fire-retardant concentrate composition of claim 16 , wherein the xanthan gum is in an amount of from about 2.0% to about 8.0% by weight of the total concentrate composition.
28. The fire-retardant concentrate composition of claim 16 , wherein the xanthan gum is in an amount of from about 2.0% to about 3.0% by weight of the total concentrate composition.
29. The fire-retardant concentrate composition of claim 16 , wherein the resulting aqueous solution exhibits a magnesium alloy corrosion rate equal to or less than 3.0 milli-inches per year.
30. The fire-retardant concentrate composition of claim 1 , wherein the resulting aqueous solution exhibits a magnesium alloy corrosion rate equal to or less than 3.0 milli-inches per year.