Abstract
Purification of iron oxide obtained from Iron Precipitation of the Zinc leaching residues with Na2B407 flux have been investigated by use of the recrystallization method.
And, the effects of retention time at 1, 200°C, cooling rate, iron oxide/flux ratio, CuO and NaF additions on size, purity and the yield of hematite crystal were tested.
The main results obtained are as follows:
(1)The size of hematite crystals decreased with the increasing cooling rate from 1°C/min to 10°C/min.
(2) The purity of hematite crystals was about>99.8% of Fe203, and the contents of Zn, S, As were 130-300 ppm, 7-20ppm and about 30 ppm, respectively.
(3) The yield of hematite crystals increased up to>80% with increasing cooling rate and the iron oxide/flux ratio and with an increase of NaF addition.
