The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 21, 1995
Filed:
Jul. 29, 1994
Kai Butje, Duisburg, DE;
Jurgen Kischkewitz, Ratingen, DE;
Bayer Aktiengesellschaft, Leverkusen, DE;
Abstract
A process for the preparation of very pure titanium dioxide by reacting titanium tetrahalides with sulphuric acid, hydrolysis the titanyl sulphate solution obtained and calcining the hydrolysate is disclosed wherein the reaction between titanium tetrahalide and aqueous 20-40% by weight strength sulphuric acid is performed in such a way that crystallisation of titanyl sulphate does not take place, the hydrogen halide is separated, the solution is optionally concentrated and filtered and then the ratio by weight of sulphuric acid to titanium dioxide is adjusted to between 1.7 and 2.0 and the titanium dioxide concentration is adjusted to between 250 and 300 g/l, the solution is hydrolyzed and the resulting titanium oxide hydrate is filtered off and calcined to give Futile or anatase.