Potassium formate

Names Preferred IUPAC name Identifiers ChemSpider ECHA InfoCard 100.008.799 Edit this at Wikidata UNII Properties CHKO₂ Molar mass 84.115 g·mol⁻¹ Appearance Colorless deliquescent crystals Density 1.908 g/cm³ Melting point 167.5 °C (333.5 °F; 440.6 K) Boiling point Decomposes 32.8 g/100 mL (0 °C)
331 g/100 mL (25°C)
657 g/100 mL (80 °C) Solubility soluble in alcohol
insoluble in ether Basicity (pK_b) 10.25 Hazards GHS labelling: GHS07: Exclamation mark Warning H315, H319, H335 P261, P280, P302+P352, P305+P351+P338 Lethal dose or concentration (LD, LC): 5500 mg/kg (oral, mouse)

Potassium formate, HCO₂K, HCOOK, or KHCO₂, is the potassium salt of formic acid. This strongly hygroscopic white solid^[2] is an intermediate in the formate potash process for the production of potassium.^[3] Potassium formate has also been studied as a potential environmentally friendly deicing salt for use on roads.^{[4] [5]} It has also been suggested for use in a less corrosive liquid desiccant.^[6] A 52% solution of potassium formate has a freezing point of −60 °C (−76 °F).^[7] Potassium formate brines are sometimes used for heat transfer, despite being much more corrosive than many other liquid coolants, especially to zinc and aluminum but even to many steels,^[8] though some formulations are compatible with aluminum and steels.^[9]

Since 1995, potassium formate has been increasingly used in aqueous drilling fluids to increase density, stabilize the hole, and improve drilling performance.^{[10] [11] [12]}