Patent ID: 6740769
Filing Date: 2004-05-25
Classification: B01J,C07C,Y02P

Abstract:
A process for producing a molybdenum-bismuth-iron-containing metal oxide fluidized bed catalyst containing molybdenum, bismuth, iron and silica as essential components and having a controlled particle diameter, the process comprising:spray-drying a slurry containing catalyst components to effect granulation, subjecting the dry particles obtained by the spray-drying to classification to separate dry particles having a particle diameter outside a desired range, and feeding dry particles having a particle diameter within the desired range to subsequent calcination step, pulverizing the dry particles having a particle diameter outside the desired range so as to have a particle diameter of 10 &mgr;m or less to obtain a pulverized product, and mixing the pulverized product into the slurry containing catalyst components at any desired stage prior to the spray-drying so as to be in the range of not more than 50% by weight in terms of oxides based on oxides of a completed catalyst after the spray drying and the calcination, wherein the metal oxide fluidized bed catalyst is a catalyst having a composition represented by the formula MOaBibFecQdReXfYgOh(SiO2)i â€ƒwhere Mo, Bi, Fe and O respectively represent molybdenum, bismuth, iron and oxygen, Q represents at least one element selected from the group consisting of nickel, cobalt, magnesium, chromium, manganese and zinc. R represents at least one element selected from the group consisting of beryllium, phosphorus, boron, arsenic, selenium, lithium, sodium, potassium, rubidium, cesium, thallium and tellurium, X represents at least one element selected from the group consisting of vanadium, tungsten, yttrium, lanthanum, zirconium, hafnium, niobium, tantalum, aluminum, calcium, strontium, barium, lead, copper, cadmium, gallium, indium, germanium, antimony, tin and cerium, Y represents at least one element selected from the group consisting of praseodymium, neodymium, samarium, europium, gadolinium, thorium, uranium, rhenium, ruthenium, rhodium, palladium, osmium, iridium, platinum, silver and gold, and SiO2 represents silica; suffixes a, b, c, d, e, f, g, h and i represent atomic ratios of the respective elements. provided that when a=10, then 0.1&lE;b&lE;5, 0.1&lE;c&lE;10, 0&lE;d&lE;8, 0&lE;e&lE;3, 0&lE;f&lE;8, 0&lE;g&lE;2 and 10&lE;i&lE;200; and h is the number of oxygen atoms necessary for satisfying valencies of the above respective components.