The vanadium slag (V-slag) is generated from smelting vanadium
titanomagnetite ore, which contains valuable elements, such as V, Ti, Cr, Fe
and Mn. The traditional methods were mainly focused on the extractions of V
and Cr by oxidation or reduction processes. In the present work,
chlorination method was adopted to keep the valence state of each elements
as original state. In order to speed up the diffusion of elements and reduce
volatility of molten salt, microwave heating has been examined in the
current paper. The results indicated that it only took 30 min to chlorinate
V-slag at 800 ?C, and the chlorination ratios of V, Cr, Mn, Fe and Ti could
reach to 82.67%, 75.82%, 92.96%, 91.66% and 63.14%, respectively. Compared
with the results by conventional heating for 8 h, this extraction rate by
microwave heating shows greater advantages. In addition, microwave heating
can reduce effectively volatilization of AlCl3 by shortening the reaction
time. The volatilization ratio of AlCl3 in this microwave heating was 3.92%
instead of 8.97% in conventional heating (1h). The mechanism of efficient
chlorination can be summarized as the enhancement of ions diffusion process
and enhanced chemical reaction due to local high temperature.
High efficiency extractions of V, Cr, Ti, Fe and Mn from vanadium slag by microwave heating