Porous structures of iron, cobalt and nickel chromites

Abstract The porous structures of FeCr 2 O 4 , CoCr 2 O 4 and NiCr 2 O 4 as well as of the products of their activation with potassium ions (up to 5 mol.% K 2 O) were investigated. The nature of porosity of the above solids appeared to be polydispersive. Potassium ions, introduced during syntheses of these spinel-type compounds, caused an increase in the volume of the micropores and mesopores.