Separation of TiO2 and Fe2O3 from Indonesia Ilmenite Minerals and their Application as Photocatalysts for Eriochrome Black-T Dye Degradation

Anatase-TiO2 and alpha-Fe2O3 were successfully separated from Indonesia ilmenite minerals using a modification of the hydrometallurgy process. Sodium salt was used as an initiated roasting before hydrochloric leaching. The study investigated parameters that affect separation such as mass ratios of sodium salt to ilmenite and leaching temperature. The results revealed that Ti composition in residue-TiO2 increased to 76 % while Fe-composition in filtrate-Fe2O3 was 87 %. The XRD diffractogram analysis confirmed that main phase formed in residue of separation was anatase-TiO2 whereas in hydrolysed of filtrate from separation was hematite. Both residue-TiO2 and filtrate Fe2O3 had high thermal stability. The photocatalytic activity of anatase-TiO2 and alpha-Fe2O3 showed about 97 % and 85 % of Eriochrome Black-T dye solution was degraded, respectively, when conducted to 4 hours of UV light irradiation. Photocatalytic kinetics study of anatase-TiO2 and alpha-Fe2O3 in degradation process followed pseudo-first order with reaction rate at 0.0144 and 0.0070 min(-1), respectively.