Experimental Study on Separation of Iron and Titanium from Vanadium-titanium Iron Concentrate by Hydrochloric Acid Leaching at Atmospheric Pressure

The elements of vanadium-titanium iron concentrate were selectively leached by hydrochloric acid at atmospheric pressure,and the effects of liquid-solid ratio,leaching temperature and time,and hydrochloric acid concentration on the leaching rate of iron and titanium dioxide （TiO₂） were studied. Furthermore,the microstructure,morphology,size and elements distribution of the leaching residue were also investigated. The results show that the magnetite phase is destroyed by hydrochloric acid leaching and obvious pulverization is discovered on the surface of leaching residue,with Fe entering into the leaching solution. However,the ilmenite phase has not been destroyed and still exists in the leaching residue. The optimal leaching conditions are as follows: 18.6% of hydrochloric acid concentration,leaching at 85 ℃ for 60 min,and 9:1 of liquid-solid ratio.At the optimal conditions,the leaching ratio of Fe and TiO₂ are 85.41% and 7.22%,respectively. The yield of leaching residue is 27% and the grade of TiO₂ in the leaching residue is about 34%.