Ammonium formate

Ammonium formate, NH₄HCO₂, is the ammonium salt of formic acid. It is a colorless, hygroscopic, crystalline solid.

Pure ammonium formate decomposes into formamide and water when heated, and this is its primary use in industry. Formic acid can also be obtained by reacting ammonium formate with a dilute acid, and since ammonium formate is also produced from formic acid, it can serve as a way of storing formic acid.

Ammonium formate can also be used in palladium on carbon (Pd/C) reduction of functional groups. In the presence of Pd/C, ammonium formate decomposes to hydrogen, carbon dioxide, and ammonia. This hydrogen gas is adsorbed onto the surface of the palladium metal, where it can react with various functional groups. For example, alkenes can be reduced to alkanes, or formaldehyde to methanol. Activated single bonds to heteroatoms can also be replaced by hydrogens (hydrogenolysis).