Assertion: hydrated titanium dioxide | /r/HasProperty | -3- sf
Facets:
Source sentences:
text: c a) grinding the titanium dioxide bearing material to form a particulate raw feed material; b) contacting the particulate raw feed material with predetermined amount of sulphuric acid in a relation vessel and introducing a gas consisting of preheated air into the7 reaction vessel to raise the temperature in the reaction vessel to a predetermined temperature at which a reaction takes place to produce a cake material containing titanyl sulphate; c) contacting the cake material with a sufficient quantity of water, and optionally recovered process to acid, to dissolve the cake material, which contains the titanyl sulphate; d) filtering the resultant suspension and collecting the solution containing the titanyl sulphate; e) hydrolysing the titanyl sulphate containing solution by contacting the solution with water, which has first been seeded with an appropriate amount of rutile and heated, or portion of previously hydrolysed solution containing hydrated titanium dioxide, and heating the solution to boiling point to precipitate out hydrated titanium dioxide -3- Sf) washing the hydrolysate with an ammonium solution to remove residual sulphate as ammonium sulphates followed Sby filtering off the hydrated titanium dioxide; or filtering the Shydrolysate followed by washing with sodium hydroxide, Ci 5 ammonium hydroxide, water, phosphoric acid and/or diluted sulphuric acid; and 00 g) calcining the hydrolysate to drive off any residual acid and IND water of crystallisation to produce titanium dioxide.