Abstract: Effective and environmentally benign liquid deicing and anti-icing compositions are provided by aqueous solutions of (a) alkali metal acetates, preferably KAc, (b) phosphate ion, e.g., H.sub.3 PO.sub.4 or K.sub.3 PO.sub.4, (c) soluble silicate,, e.g., K.sub.2 SiO.sub.3 or Na.sub.2 SiO.sub.3, (d) aromatic triazole, preferably tolyltriazole, (e) a dye which provides a visible hue, and (f) a compatible surfactant which lowers the surface tension to below about 50 dynes per sq. cm., prevents aggregation of components (a) to (f), and assures excellent dispersion across aircraft surfaces, preferablty octylphenoxypolyethoxy ethylphosphate. These compositions are environmentally safe and are useful in methods for deicing or preventative anti-icing of aircraft that meet AEA, ISO and SAE aviation standards. These compositions remain effective at low temperatures and are non-corrosive to metals used in aircraft construction.

Abstract: Liquid deicing and anti-icing compositions are provided by aqueous solutions of (a) alkali metal acetates, e.g., KAc or NaAc, (b) phosphate ion, e.g., K.sub.3 PO.sub.4, and (c) soluble silicate, e.g., K.sub.2 SiO.sub.3 or Na.sub.2 SiO.sub.3. These compositions are environmentally safe and meet FAA standards for metal corrosion resistance. They are effective at very low temperatures, e.g. -40.degree. F., and provide particularly effective deicing compositions when used in combination with granular CMA.