Br. Reddy et al., CORRELATION OF NICKEL EXTRACTION WITH IRON REDUCTION IN OXIDIC NICKELORE BY A THERMOGRAVIMETRIC METHOD, Thermochimica acta, 264, 1995, pp. 185-192
The reduction roasting of chromite overburden with CO/CO2/N-2 gas mixt
ure in the temperature range 700-750 degrees C has been shown to resul
t in the formation of metallic nickel and different lower valence stat
es of iron, viz: magnetite, wustite and metallic iron. The reduced cal
cine was cooled to room temperature under an inert atmosphere and leac
hed with ammonia-ammonium carbonate solution to bring the metallic nic
kel into soluble form. This paper reports the results from estimation,
by thermogravimetric (TG) and chemical methods, of the percentage iro
n reduced to lower oxide stages such as magnetite and wustite in the c
alcine under different experimental conditions. Further, the percentag
e extraction of nickel is correlated with iron reduction.y