Fluidizable particulate materials and methods of making same
Gupta, R. (1999). IPC No. U.S.Fluidizable particulate materials and methods of making same (Patent No. 5972835.)
The invention provides fluidizable, substantially sphericalparticulate material of improved attrition resistance having anaverage particle size from about 100 to about 400 microns useful assorbents, catalysts, catalytic supports, specialty ceramics or thelike. The particles are prepared by spray drying a slurrycomprising inorganic starting materials and an organic binder.Exemplary inorganic starting materials include mixtures of zincoxide with titanium dioxide, or with iron oxide, alumina or thelike. Exemplary organic binders include polyvinyl alcohol,hydroxypropylemethyl cellulose, polyvinyl acetate and the like. Thespray dried particles are heat treated at a first temperaturewherein organic binder material is removed to thereby provide aporous structure to the particles, and thereafter the particles arecalcined at a higher temperature to cause reaction of the inorganicstarting materials and to thereby form the final inorganicparticulate material.