Process of providing titanium dioxide and/or vanadium oxide

The process of any one of the preceding claims, wherein the alkaline material is added to the feedstock in an amount of 3 to 20 wt %, based on the total weight of the feedstock, preferably wherein the alkaline material is added to the feedstock in an amount of 5 to 15 wt %, based on the total weight of the feedstock.

The process of any one of the preceding claims, wherein the roasting in step (c) is at a temperature in the range of 600° C. to 800° C.

The process of any one of the preceding claims, wherein the roasting in step (c) is for 0.5 hours to 4 hours.

The process of any one of the preceding claims, wherein the roasted calcine has a pH of less than 9.0, preferably wherein the roasted calcine has a pH in the range of 6.0 to 8.0.

The process of any one of the preceding claims, wherein the process comprises

• (d) leaching at least a portion of the roasted calcine under acidic conditions to provide a pre-cure leach solid and a pre-cure leach liquor;
• and
• (f) adding sulphuric acid and/or hydrochloric acid to at least a portion of the pre-cure leach solid to provide a first acidic solid.

The process of any one of the preceding claims, wherein the process comprises (e) obtaining vanadium oxide from at least a portion of the pre-cure leach liquor via solvent extraction and/or precipitation.

The process of any one of the preceding claims, wherein the feedstock further comprises aluminium, and where the process further comprises obtaining aluminium oxide from at least a portion of the pre-cure leach liquor via precipitation.

The process of any one of the preceding claims, wherein the process further comprises pelletizing the first acidic solid before curing step (g).

The process of any one of the preceding claims, wherein the curing in step (g) is at a temperature in the range of 100° C. to 200° C.

The process of any one of the preceding claims, further comprising pulverizing the at least a portion of the cured first acidic solid before leaching step (h).

The process of any one of the preceding claims, wherein the leaching of the at least a portion of the cured first acidic solid in step (h) is at a pH of less than 3.0.

The process of any one of the preceding claims, wherein the leaching of the at least a portion of the cured first acidic solid in step (h) is at a pH of less than 2.0.

The process of any one of the preceding claims, wherein the process comprises separating the post-cure leach solid and the post-cure leach liquor, preferably via filtration.

The process of any one of the preceding claims, wherein the hydrolysing at least a portion of the post-cure leach liquor in step (i) is at a temperature in the range of 50° C. to 80° C., preferably wherein the hydrolysing at least a portion of the post-cure leach liquor in step (i) is at a temperature in the range of 50° C. to 70° C.

The process of any one of the preceding claims, wherein the feedstock further comprises manganese, iron, chromium, and/or nickel, and wherein the process further comprises obtaining manganese, iron, chromium, and/or nickel from at least a portion of the post-cure leach liquor via solvent extraction and/or precipitation.

The process of any one of the preceding claims, wherein the feedstock comprises a slag comprising titanium and/or vanadium, or wherein the feedstock comprises one or more of the group consisting of ilmenite, leucoxene, rutile, and complex calcium magnesium aluminium silicates.

The process of any one of the preceding claims, wherein the feedstock comprises 0.3 to 5.0 wt % vanadium and/or 5.0 to 85.0 wt % titanium dioxide, based on the total weight of the feedstock.

The process of any one of the preceding claims, wherein the process is a process of providing titanium dioxide and vanadium oxide, and wherein the process comprises

• (i) hydrolysing at least a portion of the post-cure leach liquor to provide titanium dioxide, and
• (j) obtaining vanadium oxide from at least a portion of the post-cure leach liquor via solvent extraction and/or precipitation.

The process of any one of the preceding claims, wherein step (f) further comprises adding water to at least a portion of the roasted calcine or at least a portion of the pre-cure leach solid.