Thermal decomposition of potassium cobalt hexacyanoferrate(II)

Potassium cobalt hexacyanoferrate(II), K₂CoFe(CN)₆ · 1.4H₂O, loses its water when heated up to 170°C, and the anhydrous compound begins to decompose above 230°C. The cyanide groups are evaporated off in the temperature range 230–350°C, and the solid products thus formed are K₂CO₃, Fe₂O₃, Co₃O₄ and CoFe₂O₄. In the range 550–900°C, the cobalt-containing compounds become CoO, and K₂CO₃ probably partly decomposes to K₂O, so that the product mixture at 900°C is K₂CO₃/K₂O, Fe₂O₃ and CoO. Above this temperature, K₂CO₃ decomposes to K₂O.