Silica and Iron Recovery from a Residue of Iron Ore Flotation

Abstract

A study of silica and iron recovery from the iron ore concentration tailing is presented. The residue is composed of 40.1% Fe, 33.4% SiO 2 , 8.31% Al 2 O 3 , 0.08% P, and 0.34% MnO. The developed process of silica and iron recovery consisted of size classification, magnetic separation, and removal of impurities by leaching. A concentration of SiO 2 from 33.4% to 67.0%, with 60.0% of mass reduction, was achieved by size classification. After magnetic separation, the SiO 2 grade increased from 67.0% to 95.0%, in non-magnegtic fraction and iron increased from 40.1% to 60.2% in magnetic fraction. The iron content in magnetic fraction achieved the commercial grade. In order to increase the content of silica, the impurities removal from the non-magnetic fraction was studied. The leaching agents investigated were HCl, H 2 SO 4 , HNO 3 , HF, C 6 H 8 O 7 , (COOH) 2 •2H 2 O and NaOH. A concentration of 98.0% SiO 2 was attained with the acid digestion.

Economic appraisal of iron ore deposit in Buttala, Sri Lanka: Preliminary mineral and chemical evidences

“…The silica mainly comes into the ore due to the accompany of quartz and silicate associated clay minerals. By employing usual floatation or magnetic separation methods, amount of silicate minerals can be reduced (Martins et al, 2017).…”