Anatase TiO<sub>2</sub> Enrichment from Bangka Ilmenite (FeTiO<sub>3</sub>) and its Photocatalytic Test on Degradation of Congo Red

Abstract

Anatase TiO2 enrichment from Bangka ilmenite (FeTiO3) has been conducted. First, ilmenite was mechanically activated using a planetary ballmill to obtain sub-micron sized particle followd by magnetic separation. Chemical treatment, dissolution of iron using hydrochloric solution, was performed to obtain titania rich residue. EDX data shows that the iron content was reduced in the titania residue. Ammonium hydroxide (NH4OH) solution was added to the washed precipitate, before adding H2O2 solution (10%) that acted as a coordination agent to leach titanium from the the residue in the form of ammonium peroxo titanate solution. The peroxo titanate powder was obtained by evaporating the ammonium peroxo titanate solution. XRD data show that TiO2 anatase was formed after peroxo titanate powder was calcined at the temperature of 600°C. EDX data also shows that the obtained anatase TiO2 still has impurities, such as silicon (0.98%) and iron (2.75%). Its photocatalytic activity was studied on photodegradation of Congo Red and compared with the photocatalytic activity of commercial TiO2, Degussa P-25. The photoreactivity test on degradation of Congo Red solution with the as-prepared Anatase gave 20% degradation which is still inferior compared to the results given by Degussa P25 (92%). This indicates that the impurities in as-prepared Anatase may cover the titania surface hindering the contact between Congo Red as well as UV-light and the active titania species.