Patent application number | Description | Published |
20080293968 | Method for regenerating catalyst for the production of methacrylic acid and process for preparing methacrylic acid - A catalyst for the production of methacrylic acid comprising a heteropolyacid compound containing phosphorus and molybdenum is regenerated by a method comprising the steps of drying a mixture containing a deactivated catalyst, an ammonium ion, a nitrate ion and water, molding the dried mixture, firstly calcining the molded product in an atmosphere of an oxidizing gas at a temperature of 360 to 410° C., and then secondly calcining the product in an atmosphere of a non-oxidizing gas at a temperature of 420 to 500° C. The regenerated catalyst has substantially the same catalytic activity as a fresh catalyst in a gas phase catalytic oxidation reaction of methacrolein, isobutylaldehyde, isobutane or isobutyric acid to prepare methacrylic acid. | 11-27-2008 |
20090259070 | METHOD FOR REGENERATING CATALYST FOR THE PRODUCTION OF METHACRYLIC ACID AND PROCESS FOR PREPARING METHACRYLIC ACID - A catalyst for the production of methacrylic acid comprising a heteropolyacid compound containing phosphorus and molybdenum is regenerated by a method comprising the steps of heat-treating a mixture containing a deactivated catalyst, water, a nitrate ion and an ammonium ion having a molar ratio to the nitrate ion of 1.3 or less at a temperature of at least 100° C., drying the mixture to obtain a dried catalyst, and calcining the dried catalyst. The regenerated catalyst has substantially the same catalytic activity as a fresh catalyst in a gas phase catalytic oxidation reaction of methacrolein, isobutylaldehyde, isobutane or isobutyric acid to prepare methacrylic acid. | 10-15-2009 |
20090259071 | METHOD FOR REGENERATING CATALYST FOR THE PRODUCTION OF METHACRYLIC ACID AND PROCESS FOR PREPARING METHACRYLIC ACID - A catalyst for the production of methacrylic acid comprising a heteropolyacid compound containing phosphorus and molybdenum is regenerated by a method comprises the steps of heat-treating a deactivated catalyst at a temperature of at least 350° C., mixing the deactivated catalyst with water, a nitrate ion and an ammonium ion, then drying the mixture to obtain a dried catalyst, and calcining the dried catalyst. | 10-15-2009 |
20090287018 | METHOD FOR PRODUCING CATALYST FOR USE IN PRODUCTION OF UNSATURATED ALDEHYDE AND/OR UNSATURATED CARBOXYLIC ACID, AND METHOD FOR PRODUCING UNSATURATED ALDEHYDE AND/OR UNSATURATED CARBOXYLIC ACID - A catalyst for use in the production of an unsaturated aldehyde and/or an unsaturated carboxylic acid, the catalyst comparing (or, preferably, being composed of) a mixed oxide containing molybdenum, bismuth and iron, which has improved mechanical strength, is produced by a method including the steps of (1) drying an aqueous solution or an aqueous slurry containing raw materials of the catalyst and then firstly calcining a dried product in a molecular oxygen-containing gas atmosphere to obtain a calcined product; (2) heating the calcined product obtained in Step (1) in the presence of a reducing material to obtain a reduced product having a mass loss of 0.05 to 6%; and (3) secondly calcining the reduced product obtained in Step (2) in a molecular oxygen-containing gas atmosphere. | 11-19-2009 |
20110077148 | PROCESS FOR PRODUCING COMPLEX OXIDE CATALYST - A process is provided for producing a complex oxide catalyst which exhibits superior catalytic activity in a vapor phase catalytic oxidation reaction, particularly in production of unsaturated aldehyde and unsaturated carboxylic acid. The process is characterized by the steps of preparing an aqueous slurry by mixing a complex oxide containing molybdenum and cobalt with an acid and water; drying the aqueous slurry; and calcining the resulting dried solid. Preferably, the complex oxide is obtained as follows: a molybdenum- and cobalt-containing complex oxide catalyst which has been used in a vapor phase catalytic oxidation reaction is mixed with an aqueous extracting solution obtained by dissolving at least one of ammonia and an organic base in water, to thereby extract molybdenum and cobalt into the aqueous phase; and the aqueous phase is dried and is then calcined under an atmosphere of an oxidizing gas. | 03-31-2011 |
20110105789 | METHOD FOR PRODUCING CATALYST FOR PREPARATION OF METHACRYLIC ACID AND METHOD FOR PREPARING METHACRYLIC ACID - A method for producing a catalyst for the preparation of methacrylic acid comprising a heteropolyacid compound containing phosphorus, molybdenum and an element X selected from the group consisting of potassium, rubidium, cesium and thallium and having an atomic ratio of the element X to molybdenum of 0.5:12 to 2:12, which method comprises the steps of mixing aqueous slurry A containing starting compounds of the heteropolyacid compound in which an atomic ratio of the element X to molybdenum is from 2:12 to 4:12, and aqueous slurry B containing starting compounds of the heteropolyacid compound in which an atomic ratio of the element X to molybdenum is from 0:12 to 0.5:12 to form a slurry mixture; heat-treating the slurry mixture at a temperature of 100° C. or higher; drying the slurry mixture; and calcining the dried mixture. | 05-05-2011 |
20120289741 | METHOD FOR PRODUCING CATALYST FOR USE IN PRODUCTION OF UNSATURATED ALDEHYDE AND/OR UNSATURATED CARBOXYLIC ACID, AND METHOD FOR PRODUCING UNSATURATED ALDEHYDE AND/OR UNSATURATED CARBOXYLIC ACID - A catalyst for use in the production of an unsaturated aldehyde and/or an unsaturated carboxylic acid, the catalyst comparing (or, preferably, being composed of) a mixed oxide containing molybdenum, bismuth and iron, which has improved methanical strength, is produced by a method including the steps of (1) drying an aqueous solution or an aqueous slurry containing raw materials of the catalyst and then firstly calcining a dried product in a molecular oxygen-containing gas atmosphere to obtain a calcined product; (2) heating the calcined product obtained in Step (1) in the presence of a reducing material to obtain a reduced product having a mass loss of 0.05 to 6%; and (3) secondly calcining the reduced product obtained in Step (2) in a molecular oxygen-containing gas atmosphere. | 11-15-2012 |
20130261335 | PROCESS FOR PRODUCING ALKYL METHACRYLATE - An object of the present invention is to provide a process for producing methacrylic acid with good productivity over a long period of time. | 10-03-2013 |