| 摘要 |
<p>High quality titanium dioxide is produced by the sulphuric acid decomposition process by reacting ilmenite and/or titanium-containing slags with high-percentage sulphuric acid, dissolving the solid decomposition materials with metal sulphate-containing aqueous sulphuric acid and optionally water and reducing the trivalent iron and separating off the insoluble crude material fraction to obtain a foreign metal salt-rich sulphuric acid-containing titanyl sulphate solution, additionally called black solution, hydrolysing the black solution with subsequent removal of the precipitated titanium oxide hydrate, intensive water washing, drying and optionally calcination, the black solution being brought into contact before the hydrolysis with an organic medium, additionally called "extracting agent", and reextraction, additionally called "stripping", of the organic phase formed in this process by means of water and/or an aqueous solution containing sulphuric acid and/or titanyl sulphate with return of the organic phase obtained in this process into the extraction, the metal sulphate-containing sulphuric acid obtained in the extraction, additionally called dilute extraction acid, being employed for dissolving the solid decomposition material. <IMAGE></p> |
