PROCESS FOR THE RECOVERY OF TITANIUM DIOXIDE AND VALUE METALS BY REDUCING THE CONCENTRATION OF HYDROCHLORIC ACID IN LEACH SOLUTION AND SYSTEM FOR SAME

摘要

The present invention describes a process and system for recovering titanium dioxide and other value metals from a titanium bearing solid. The process comprises (a) leaching the solid in hydrochloric acid to produce a leachate comprising undissolved solids and a leach solution comprising the titanium dioxide and the value metals, wherein the hydrochloric acid concentration is maintained above a value required to maintain the titanium dioxide and the value metals dissolved in the leach solution at atmospheric pressure; (b) separating the leachate into the leach solution and the undissolved solids; and (c) reducing the concentration of hydrochloric acid concentration in the leach solution to recover titanium dioxide by hydrolysis and precipitation to produce a titanium dioxide rich slurry. In a preferred embodiment, HCl is recovered with a matrix solution.