Abstract: A composite membrane structure is used in a distillation apparatus and method. The composite membrane separates a distilland and a distillate, such as salt water and fresh water. The composite membrane comprises a thin lyophobic microporous layer or membrane and a thin lyophilic layer or membrane. Evaporation and condensation takes place within the micropores of the lyophobic membrane. The lyophilic layer prevents intrusion of distilland into the pores of the lyophobic layer.

Abstract: A process and apparatus are provided for making hollow macrospherical particles. The particles themselves are particularly adapted for use as anti-perspirants. The particles have a diameter between about 10 and 74 microns, preferably predominating between 15 and 44 microns, and a greater than unit density. As such, they are not subject to deep lung penetration. The process for producing the particles comprises providing a solution containing the materials from which the particles are made, diffusing the solution through small pores by centrifugal force such that the resulting hollow particles have a diameter greater than the pore diameter, and drying the solution droplets in a stream of heated air. The apparatus for producing the macrospherical particles comprises a centrifugal atomizer having a porous sintered metal filter ring which is rotated inside a spray drying chamber.