| Patent application number | Description | Published |
|---|
| 20080200685 | Method for Preforming Oxidation Catalysts - Processes comprising providing a catalyst precursor, and heating the catalyst precursor to a temperature of at least 350° C. in an atmosphere comprising air, wherein air is fed into the atmosphere at a rate of 0.05 to 4.0 standard m | 08-21-2008 |
| 20080312450 | Method for Start-Up of Oxidation Catalysts - Methods comprising: providing an oxidation catalyst bed; and starting up the oxidation catalyst at a temperature of 360° C. to 400° C. with an amount of air of 1.0 to 3.5 standard m | 12-18-2008 |
| 20090171101 | METHOD FOR GAS PHASE OXIDATION USING A MODERATOR LAYER - A process for gas phase oxidation in which a gaseous stream which comprises at least one aromatic hydrocarbon and molecular oxygen is passed through one or more catalyst layers, wherein a moderator layer is arranged between two catalyst layers arranged in succession in flow direction of the gaseous stream, the moderator layer being less catalytically active than the catalysts adjacent upstream and downstream or being catalytically inactive. The desired oxidation products are obtained in high yield over prolonged periods. | 07-02-2009 |
| 20090286999 | CATALYST SYSTEM FOR PREPARING CARBOXYLIC ACIDS AND/OR CARBOXYLIC ANHYDRIDES - The present invention relates to a catalyst system for preparing carboxylic acids and/or carboxylic anhydrides which has at least three catalyst layers arranged one on top of the other in the reaction tube, with the proviso that the most inactive catalyst layer is preceded in the upstream direction by a more active catalyst layer. The invention further relates to a process for gas phase oxidation in which a gaseous stream which comprises one hydrocarbon and molecular oxygen is passed through a plurality of catalyst layers, the least active catalyst layer being upstream of a more active catalyst layer. | 11-19-2009 |
| 20100029955 | CATALYST SYSTEM AND METHOD FOR GAS PHASE OXIDATION USING AN UPSTREAM LAYER - The present invention relates to a process for gas-phase oxidation, in which a gaseous stream comprising an aromatic hydrocarbon and molecular oxygen is passed through two or more catalyst zones. Furthermore, the present invention relates to a catalyst system for gas-phase reaction using a preliminary zone. | 02-04-2010 |
| 20110034707 | METHOD FOR STARTING A GAS-PHASE OXIDATION REACTOR - 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. | 02-10-2011 |
