ABSTRACT
Background of the Process . . . . . . . . . . . . . . . . . . . 223
Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 224
Brief Description of the Drawing . . . . . . . . . . . . . . 224
Detailed Description of the Invention . . . . . . . . . 224
Drying of Spray by Moisture Removal . . . . . . 225
Separation of Dried Product from the Air . . 225
Ultimate Particle Size of the Feed . . . . . . . . . . 225
Concentration of Solids in the Feed . . . . . . . . 225
Viscosity and Temperature of the Feed . . . . . 226
Feed Rate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 226
Atomization of Feed into a Spray . . . . . . . . 226
Spray-Air Contact . . . . . . . . . . . . . . . . . . . . 226
Drying of Spray . . . . . . . . . . . . . . . . . . . . . . 226
There is disclosed a process for preparing superficially porous macroparticles comprising spray drying a
specified well-mixed slurry of core macroparticles, colloidal inorganic microparticles and a liquid, and sin-
tering the resulting product to cause a 5-30% decrease in surface area.
