Phase evolution and cobalt and sulfur content of complex cobalt-sulfur concentrate during oxidative roasting

摘要

Oxidation roasting is the most effective method for treating sulfur in pyrite, Study the calcination temperature and time on cobalt and sulfur during oxidative roasting. After oxidizing roasting of a cobalt ore concentrate in a concentrator in Sichuan, the sulfur in the sample was basically removed, so that the cobalt grade increased from about 6% to about 9%. The results show that the desulfurization effect is best at 900°C and calcination for 2.5 hours. The grade of cobalt is also increased by about 50% compared to that before roasting. In the phase transformation analysis of the specific calcination process, it is concluded that from the beginning of500°C, pyrrhotite, magnetite and hematite are formed in sequence, and the talc gradually disappears during the temperature increase, and the magnesium iron tip is formed in parallel. The spar, a small amount of chromium forms a zinc spinel in the form of a lattice substitution, and a part of the cobalt magnesium element is lattice substituted into the chromite to form cobalt magnesium chromite ore and cobalt chromite. After 600°C, there is a significant change in the spectrum. At this time, some hematite, maghemite and magnetite are formed. Until the 900°C map tends to be stable, pyrite and pyrite (FeS_2) are largely converted into hematite and maghemite (Fe_2O_3), but some magnetite (Fe_3O_4) still exists.