Abstract:
Disclosed is a method for producing a catalyst containing vanadium, phosphorus, and oxygen, which is used for oxidizing the gas phase of a hydrocarbon having at least four carbon atoms to maleic anhydride. According to the inventive method, a corresponding catalyst precursor which contains vanadium, phosphorus, and oxygen and is provided with particles having an average diameter of at least 2 mm is converted into a catalytically active form by means of calcination, and a flow of the catalyst precursor is transported on a conveyor belt across at least one calcination area over a distance ln at an essentially steady speed in order to be calcinated. The variation over time of the gas temperature in relation to the set point value amounts to
Abstract:
Disclosed is a method for producing a catalyst containing vanadium, phosphorus, and oxygen, which is used for oxidizing the gas phase of a hydrocarbon having at least four carbon atoms to maleic anhydride. According to the inventive method, a corresponding catalyst precursor which contains vanadium, phosphorus, and oxygen and is provided with particles having an average diameter of at least 2 mm is converted into a catalytically active form by means of calcination, and a flow of the catalyst precursor is transported on a conveyor belt across at least one calcination area over a distance ln at an essentially steady speed in order to be calcinated. The variation over time of the gas temperature in relation to the set point value amounts to
Abstract:
Catalysts comprising a catalytically active composition, the catalytically active composition comprising vanadium, phosphorus, iron and oxygen, wherein the catalytically active composition has an iron:vanadium atomic ratio of 0.005 to
Abstract:
A process for preparing a vanadium, phosphorus, and oxygen catalyst precursor for preparing maleic anhydride by heterogeneously catalyzed gas-phase oxidation of a hydrocarbon having at least four carbon atoms, which comprises (a) reacting vanadium pentoxide with from 102 to 110% strength phosphoric acid in the presence of a primary or secondary, noncyclic or cyclic, unbranched or branched, saturated alcohol having from 3 to 6 carbon atoms in a temperature range from 80 to 160° C.; (b) isolating the precipitate formed; (c) setting an organic carbon content of
Abstract:
Disclosed is a method for producing a catalyst containing vanadium, phosphorus, and oxygen, which is used for oxidizing the gas phase of a hydrocarbon having at least four carbon atoms to maleic anhydride. According to the inventive method, a corresponding catalyst precursor which contains vanadium, phosphorus, and oxygen and is provided with particles having an average diameter of at least 2 mm is converted into a catalytically active form by means of calcination, and a flow of the catalyst precursor is transported on a conveyor belt across at least one calcination area over a distance 1 n at an essentially steady speed in order to be calcinated. The variation over time of the gas temperature in relation to the set point value amounts to n /2 of the calcination area, while the local difference in the gas temperature between any positions in the area of the flow of the catalyst precursor, which is located within the second half 1 n /2 of the calcination area, amounts to
Abstract:
A process for preparing a vanadium, phosphorus, and oxygen catalyst precursor for preparing maleic anhydride by heterogeneously catalyzed gas-phase oxidation of a hydrocarbon having at least four carbon atoms, which comprises (a) reacting vanadium pentoxide with from 102 to 110% strength phosphoric acid in the presence of a primary or secondary, noncyclic or cyclic, unbranched or branched, saturated alcohol having from 3 to 6 carbon atoms in a temperature range from 80 to 160° C.; (b) isolating the precipitate formed; (c) setting an organic carbon content of
Abstract:
Disclosed is a method for producing a catalyst containing vanadium, phosphorus, and oxygen, which is used for oxidizing the gas phase of a hydrocarbon having at least four carbon atoms to maleic anhydride. According to the inventive method, a corresponding catalyst precursor which contains vanadium, phosphorus, and oxygen and is provided with particles having an average diameter of at least 2 mm is converted into a catalytically active form by means of calcination, and a flow of the catalyst precursor is transported on a conveyor belt across at least one calcination area over a distance 1 n at an essentially steady speed in order to be calcinated. The variation over time of the gas temperature in relation to the set point value amounts to n /2 of the calcination area, while the local difference in the gas temperature between any positions in the area of the flow of the catalyst precursor, which is located within the second half 1 n /2 of the calcination area, amounts to
Abstract:
Production of a vanadium, phosphorous and oxygen containing catalyst precursor for the production of maleic acid anhydride comprises controlled mixing and/or heating of vanadium pentoxide with a 5- or 3-valent phosphorous compound in the presence of an alcohol followed by filtration of the resulting suspension. A process for the production of a vanadium, phosphorous and oxygen containing catalyst precursor (I) for the production of maleic acid anhydride by heterogeneously catalyzed gas phase oxidation of an at least 4C-hydrocarbon comprises reaction of vanadium pentoxide with a 5- or 3-valent phosphorous compound in the presence of a prim. or sec. optionally cyclic or branched 3-6C saturated alcohol with stirring at 80-160 degrees C followed by filtration of the resulting suspension such that at least two of the following measures are observed (a) addition of the phosphorous compound to a suspension of the alcohol and vanadium pentoxide at 50-160 degrees C whereby the contact time between the vanadium pentoxide and the alcohol prior to the addition of the phosphorous compound is no greater than 1 hour at a temperature of at least 50 degrees C; (b) mixing of the vanadium pentoxide with the phosphorous compound in the presence of the alcohol at 0-50 degrees C followed by heating to 50-160 degrees C at a rate of at least 1.5 degreesC/minute; (c) adjusting the mixing regime of the suspension to 0.01-0.6 W/kg (with respect to the physical-chemical properties of the mixed ingredients at 20 degrees C prior to reaction) and; (d) filtration at 65-160 degreesC at a filtration resistance value of no greater than 50 x 1013 mPa.s/m2 Independent claims are included for (1) the resulting catalyst precursor(I); (2) a process for the production of a catalyst (II) from the precursor (I) by contacting the precursor (I) with an atmosphere comprising oxygen, water vapor and/or an inert gas at 250-600 degrees C; (3) the resulting catalyst (II); (4) a process for the production of maleic acid anhydride at contacting an at least 4C hydrocarbon with an oxygen containing gas in the presence of catalyst (II).
Abstract:
Production of a vanadium, phosphorous and oxygen containing catalyst precursor for the production of maleic acid anhydride comprises controlled mixing and/or heating of vanadium pentoxide with a 5- or 3-valent phosphorous compound in the presence of an alcohol followed by filtration of the resulting suspension. A process for the production of a vanadium, phosphorous and oxygen containing catalyst precursor (I) for the production of maleic acid anhydride by heterogeneously catalyzed gas phase oxidation of an at least 4C-hydrocarbon comprises reaction of vanadium pentoxide with a 5- or 3-valent phosphorous compound in the presence of a prim. or sec. optionally cyclic or branched 3-6C saturated alcohol with stirring at 80-160 degrees C followed by filtration of the resulting suspension such that at least two of the following measures are observed (a) addition of the phosphorous compound to a suspension of the alcohol and vanadium pentoxide at 50-160 degrees C whereby the contact time between the vanadium pentoxide and the alcohol prior to the addition of the phosphorous compound is no greater than 1 hour at a temperature of at least 50 degrees C; (b) mixing of the vanadium pentoxide with the phosphorous compound in the presence of the alcohol at 0-50 degrees C followed by heating to 50-160 degrees C at a rate of at least 1.5 degreesC/minute; (c) adjusting the mixing regime of the suspension to 0.01-0.6 W/kg (with respect to the physical-chemical properties of the mixed ingredients at 20 degrees C prior to reaction) and; (d) filtration at 65-160 degreesC at a filtration resistance value of no greater than 50 x 1013 mPa.s/m2 Independent claims are included for (1) the resulting catalyst precursor(I); (2) a process for the production of a catalyst (II) from the precursor (I) by contacting the precursor (I) with an atmosphere comprising oxygen, water vapor and/or an inert gas at 250-600 degrees C; (3) the resulting catalyst (II); (4) a process for the production of maleic acid anhydride at contacting an at least 4C hydrocarbon with an oxygen containing gas in the presence of catalyst (II).
Abstract:
Disclosed is a method for producing a catalyst containing vanadium, phosphorus, and oxygen, which is used for oxidizing the gas phase of a hydrocarbon having at least four carbon atoms to maleic anhydride. According to the inventive method, a corresponding catalyst precursor which contains vanadium, phosphorus, and oxygen and is provided with particles having an average diameter of at least 2 mm is converted into a catalytically active form by means of calcination, and a flow of the catalyst precursor is transported on a conveyor belt across at least one calcination area over a distance 1 n at an essentially steady speed in order to be calcinated. The variation over time of the gas temperature in relation to the set point value amounts to n /2 of the calcination area, while the local difference in the gas temperature between any positions in the area of the flow of the catalyst precursor, which is located within the second half 1 n /2 of the calcination area, amounts to