Oxidation catalyst and process for its preparation
US4870195A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 8, 1988 |
| Grant date | Sep 26, 1989 |
| Priority date | — |
| Expiry date | Jun 8, 2008 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01P2006/12
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
An oxidation catalyst formed from V.sub.2 O.sub.5 and TiO.sub.2 of rutile structure is obtained by a process which comprises the following stages: PA1 (a) preparation of a solution of Ti(IV) by dissolution (partial hydrolysis) of TiCl.sub.4 in an aqueous solution at a final pH below 1.0, PA1 (b) preparation of a solution of V(IV) by heating, in order to dissolve it, solid V.sub.2 O.sub.5 suspended in an aqueous oxalic acid solution, PA1 (c) precipitation of metatitanic acid from the Ti(IV) solution at a pH not higher than 1.3, PA1 (d) precipitation of vanadium oxide from the said V(IV) solution in the presence of the metatitanic acid obtained in (c), and PA1 (e) separation of the precipitate, dyring and calcination thereof at an elevated temperature. The process provides a catalyst formed from V.sub.2 O.sub.5 and TiO.sub.2 of rutile structure, which has a specific surface area of the order of 10 to 60 m.sup.2 /g, is highly active, selective and stable under conditions of catalytic oxidation, especially under the conditions of the oxidation of o-xylene to phthalic anhydride.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.