Patent · US Active

Method for starting a gas-phase oxidation reactor

US8492566B2 · kind B2 · utility

1Cited by

6References

9Claims

0Family size

Assignee

BASF SE

Inventors

Hagen Wilmer · Ludwigshafen, DE
Jürgen Zühlke · Speyer, DE
Thomas Lautensack · Altleiningen, DE
Hans-Martin Allmann · Neunkirchen, DE
Frank Rosowski · Mannheim, DE
Cornelia Katharina Dobner · Ludwigshafen, DE

Key dates

Filing date	Apr 7, 2009
Grant date	Jul 23, 2013
Priority date	—
Expiry date	Feb 16, 2030

Classification

Technology area (CPC C)Chemistry; Metallurgy
CPC primaryC07D307/89
WIPO fieldOrganic fine chemistry
WIPO sectorChemistry

Abstract

What is described is a process for starting up a gas phase oxidation reactor for oxidation of o-xylene to phthalic anhydride, said reactor comprising at least one catalyst layer and being temperature-controllable by means of a heat carrier medium, wherein a) the catalyst layer is interrupted by a moderator layer which is less catalytically active than the catalyst layer or is catalytically inactive, b) a gas stream is passed through the reactor with an initial loading of o-xylene and at an initial temperature of the heat transfer medium, c) the loading of the gas stream is increased to a target loading and, in parallel, the temperature of the heat transfer medium is lowered to an operating temperature. The introduction of the moderator layer allows the loading to be increased more rapidly and the startup time to be shortened.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.