Nozzle for fluidized bed mixing/dispersing arrangement

A nozzle for use in a fluidized bed mixing/dispersing arrangement mounted in floor of a fluidized bed reactor, said nozzle being formed of reaction sintered silicon carbide consisting essentially of silicon carbide and unreacted metallic silicon and having a density of 3.07 to 3.14 g/cm.sup.3, said reaction sintered silicon carbide containing 8.0 to 15.9% by volume of metallic silicon wherein said reaction sintered silicon carbide is prepared by mixing silicon carbide, graphite powder and a binder so that the mixture consist of 40 to 70 parts by weight of silicon carbide, 15 to 35 parts by weight of graphite powder and 15 to 25 parts by weight of the binder per 100 parts by weight of the mixture, press molding the mixture into a desired shape, calcining the press molded body in an inert atmosphere at a temperature of 600.degree. to 1000.degree. C., impregnating the calcined body with metallic silicon in molten state, and reaction sintering the metallic silicon impregnated calcined body.