Recovery of titanium dioxide from iron compounds and organic material containing residual substance, comprises extraction with aqueous non-oxidizing mineral acid, and pyrolytic oxidation of the extracted organic residue

摘要

The recovery of titanium dioxide from iron compounds and organic material containing residual substances, comprises extracting the residual material with 15% of hydrochloric acid as an aqueous non-oxidizing mineral acid and pyrolytic oxidation of the extracted organic residue to CO 2 at 500-600[deg]C, after separation of the liquid extraction agent phase. The extraction is carried out at more than 75[deg]C or at the boiling temperature of the extraction agent. The recovery of titanium dioxide from iron compounds and organic material containing residual substances, comprises extracting the residual material with 15% of hydrochloric acid as aqueous non-oxidizing mineral acid and pyrolytic oxidation of the extracted organic residue to CO 2 at 500-600[deg]C, after separation of the liquid extraction agent phase. The extraction is carried out at more than 75[deg]C or at the boiling temperature of the extraction agent. The mineral acid containing extraction agent is supplied to the extraction process after separating the residue and the regenerated mineral acid is again supplied to the extraction process.