Inhibited aqueous deicing composition
Disclosed is an aqueous deicing and/or anti-icing composition, and the use thereof on areas in need of deicing and/or anti-icing, exhibiting substantially improved corrosion inhibition, conductivity inhibition and/or hydrogen embrittlement inhibition. Said composition comprises 40-60% by weight of at least one alkali metal carboxylate, 0.1-0.5% by weight of benzoic acid and/or at least one alkali metal benzoate, 0.05-0.5% by weight of at least one alkali metal phosphate, 0.005-0.05% by weight of at least one alkali metal metasilicate, and 0.01-0.15% by weight of succinic acid and/or at least one alkali metal succinate. Balance to 100% by weight is water and said composition is pH adjusted to pH 9-12 by addition of at least one alkali metal hydroxide and/or carbonate. Disclosed is also a method of obtaining corrosion inhibition, conductivity inhibition and/or hydrogen embrittlement inhibition by addition of 0.01-0.15% by weight of succinic acid and/or at least one alkali metal succinate to an aqueous deicing and/or anti-icing composition.
1. An aqueous deicing and/or anti-icing composition, said composition comprising:
40-60% by weight of at least one alkali metal carboxylate,
0.1-0.5% by weight of benzoic acid and/or at least one alkali metal benzoate calculated as benzoic acid,
0.05-0.5% by weight of at least one alkali metal phosphate,
0.005-0.05% by weight of at least one alkali metal metasilicate, and
0.01-0.15% by weight of succinic acid and/or at least one alkali metal succinate calculated as succinic acid,
the balance to 100% by weight being water, and
said composition being pH adjusted to pH 9-12 by addition of at least one alkali metal hydroxide and/or carbonate.
2. The composition according to claim 1 , said composition comprising:
45-55% by weight of at least one alkali metal carboxylate,
0.2-04% by weight of benzoic acid and/or at least one alkali metal benzoate calculated as benzoic acid,
0.1-0.2% by weight of at least one alkali metal phosphate,
0.01-0.03% by weight of at least one alkali metal metasilicate, and
0.05-0.1% by weight of succinic acid and/or at least one alkali metal succinate calculated as succinic acid,
the balance to 100% by weight being water, and
said composition being pH adjusted to pH 10-11 by addition of at least one alkali metal hydroxide and/or carbonate.
3. The composition according to claim 1 , said at least one alkali metal metasilicate being at least one alkali metal silicate.
4. The composition according to claim 1 , said alkali metal being potassium and/or sodium.
5. The composition according to claim 1 , said carboxylate being formate and/or acetate.
6. The composition according to claim 1 comprising:
45-55% by weight of potassium and/or sodium formate and/or acetate,
0.2-0.4% by weight of benzoic acid and/or potassium and/or sodium benzoate calculated as benzoic acid,
0.1-0.3% by weight of potassium and/or sodium phosphate,
0.01-0.03% by weight of potassium and/or sodium metasilicate and/or an anhydrous species and/or a hydrate thereof, and
0.05-0.1% by weight of succinic acid and/or potassium and/or sodium succinate calculated as succinic acid,
the balance to 100% by weight being water, and
said composition being pH adjusted to pH 10-11 by addition of potassium and/or sodium hydroxide or carbonate.
7. The composition according to claim 1 additionally comprising at least one viscosity modifier in an amount of 0.1-1.0% by weight.
8. The composition according to claim 7 , said at least one viscosity modifier being at least one hydroxyalkyl cellulose.
9. The composition according to claim 8 , said at least one hydroxyalkyl cellulose being hydroxyethyl cellulose.
10. The composition according to claim 7 , said at least one viscosity modifier being at least one microfibrillated cellulose.
11. The composition according to claim 1 additionally comprising at least one oxygen scavenger in an amount of 0.01-0.5% by weight.
12. The composition according to claim 11 , said at least one oxygen scavenger being potassium and/or sodium hydrogen sulphite.
13. A method for deicing and/or anti-icing an area in need of deicing and/or anti-icing, the method comprising application of a composition according to claim 1 to the area.
14. The method according to claim 13 , wherein the area is selected from airfield runways and taxiways, streets, roads, cycle ways, footpaths, sidewalks, bridges, backyards, parking areas, and sportsgrounds.
15. A method for obtaining corrosion inhibition, conductivity inhibition and/or hydrogen embrittlement inhibition in an aqueous deicing and/or anti-icing composition comprising as active deicing and/or anti-icing component at least one alkali metal carboxylate, said method comprising addition of succinic acid and/or at least one alkali metal succinate in an amount of 0.01-0.15% by weight calculated as succinic acid, and said method further comprising addition of benzoic acid and/or at least one alkali metal benzoate, at least one alkali metal phosphate and at least one alkali metal metasilicate.
16. The method according to claim 15 , said method comprising addition of succinic acid and/or at least one alkali metal succinate in an amount of 0.05-0.10% by weight calculated as succinic acid.
17. The method according to claim 15 , said alkali metal succinate being potassium and/or sodium succinate.
18. The method according to claim 15 , said method further comprising pH adjustment of said deicing and/or anti-icing composition by addition of at least one alkali metal hydroxide and/or carbonate to pH 9-12.
19. The method according to claim 15 , said alkali metal being potassium and/or sodium and said carboxylate being formate and/or acetate.