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 |
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 |
20090291845 | CONVERSION OF A PRECATALYST TO A CATALYTICALLY ACTIVE SILVER-VANADIUM OXIDE BRONZE - A process is described for converting a precatalyst which comprises an inert support, an organic carbon source and a multimetal oxide comprising silver and vanadium to a gas phase oxidation catalyst which comprises the inert support and a catalytically active silver vanadium oxide bronze, by treating the precatalyst thermally at a temperature of at least 350° C. in a gas atmosphere which comprises less than 10% by volume of oxygen, wherein, before the thermal treatment, the amount of the carbon source in the precatalyst is adjusted to a value below a critical amount The carbon content is reduced by burning-off at a temperature of from 80 to 200° C. in an oxygenous atmosphere with decomposition of a portion of the carbon source. The catalysts obtained serve for the gas phase partial oxidation of aromatic hydrocarbons to aldehydes, carboxylic acids and/or carboxylic anhydrides. | 11-26-2009 |
20090318712 | CATALYST SYSTEM AND METHOD FOR PRODUCING CARBOXYLIC ACIDS AND/OR CARBOXYLIC ACID ANHYDRIDES - Catalyst systems for preparing carboxylic acids and/or anhydrides, the catalyst system comprising a reaction zone and a layered catalyst, the reaction zone comprises a gas inlet region and a gas outlet region, the layered catalyst comprises an active composition and one or more middle layers, one or more first layers disposed on a side of the one or more middle layers toward the gas inlet region, and one or more second layers on a side of the one or more middle layers toward the gas outlet region, wherein the active composition content of one or more of the middle catalyst layers, based on total mass of the layered catalyst, is lower than the active composition content of the one or more first catalyst layers and is lower than one or more second catalyst layers; and processes for gas phase oxidation employing a layered catalyst of the present invention. | 12-24-2009 |
20100210857 | Three-Layered or Four-Layered Catalyst Systems for Producing Phthalic Anhydride - Catalyst systems for preparing phthalic anhydride by means of gas-phase oxidation of o-xylene and/or naphthalene, and a process for preparing phthalic anhydride using the catalyst systems | 08-19-2010 |
20110028740 | METHOD FOR STARTING A GAS PHASE OXIDATION REACTOR THAT CONTAINS A CATALYTICALLY ACTIVE SILVER-VANADIUM OXIDE BRONZE - What is described is a method for starting a gas phase oxidation reactor that contains a bed of a first catalyst whose active material comprises a catalytically active silver-vanadium oxide bronze, and at least one bed of a second catalyst whose catalytically active material comprises vanadium pentoxide and titanium dioxide, and whose temperature is controllable by means of a heat transfer medium. In the operating state, a gas stream which comprises a loading c | 02-03-2011 |