| 摘要 |
PURPOSE:To improve abrasion resistance, resistance to thermal deterioration, etc., of the title catalyst by mixing silica hydrogel, a V compd., a K compd., and a sulfate compd., spray-drying the mixture, then calcining the dried product. CONSTITUTION:A silica sol contg. colloidal silica having 4-50nm mean particle size acidified by adding an acid thereto, then adjusting the pH of the silica sol to 6-11 by adding a base. Then, hydrogen is synthesized by heating. A V compd. A a K compd. and a sulfate compd. are mixed with the otbd. silica hydrogel as Si source, and the mixture is spray-dried and calcined to form thus a fluidized catalyst for catalytic vapor phase oxidation of naphthalene. Preferred weight average particle size of spherical fine particles obtd. by the spray-drying is 60+ or -20mum, and preferred particle size distribution is defined by that the content of particles having <=44mum is 10-40wt.%. |
