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. © 1990.