The hydrogen reduction of spinel solid solutions in the Co-Mn-Ti-O system w
as investigated by a static method. Six phase regions were identified in wh
ich the gas phase is in equilibrium with various combinations of beta -Co,
TiO2 (rutile), and solid solutions of variable composition: COAMnBTi3-A-BO4
(spinel), ComMn2-mTiO4 (spinel), CoNMn1-NTiO3 (ilmenite), and ConMn1-nO (N
aCl). The equilibrium compositions of the solid solutions and the correspon
ding oxygen partial pressures were determined, and the general trends of th
e reduction of spinel solid solutions in the Co-Mn-Ti-O system were establi
shed.