| 摘要 |
PURPOSE:To obtain a fluidized catalyst improving the yield of phthalic acid anhydride by constituting the catalyst of silica, vanadium oxide, potassium oxide, cesium oxide and sulfuric acid and specifying the content of silica and the containing ratio of potassium to cesium. CONSTITUTION:A catalyst for preparing phthalic anhydride by the gaseous phase catalytic oxidation of naphthalene consists of silica, vanadium oxide, potassium oxide, cesium oxide and sulfurice acid. In this composition, the content of silica being a carrier component is set to 45-90wt.%, pref., about 60-85wt.% as SiO2 and the content of active components is set to 5510wt.%, pref., about 45-15wt.% as V2O5+K2O+Ce2O+SO3. Further, the containing ratio of K to Ce is set to 0.1-0.8 as an oxide mol. ratio [Ce2O/(K2O+Ce2O)]. A silica source is set to colloidal silica having a mean particle size of 4-50nm. By this method, a catalyst having high fluidizing properties and abrasion resistance is obtained in high yield. |
