To freeze dry a large amount of matter in a solution by separating a freeze drying processing from an environment.
This apparatus is adapted such that a solution which is dissolved in acid to be converted into radioactive salt is frozen into a solid on a longitudinally placed plate 16-24 provided on a freeze drying chamber 10. The solid is sublimated to vapor, and is condensed in a low temperature condenser 12 positioned upward a freeze drying chamber and coupled with the freeze drying chamber by a conduit 70. The low temperature condenser is prevented from being contaminated owing to matter such as radioactive material separated from the solution by vertically positioning the low temperature condenser with respect to a freeze dryer 1. The system is filled with inactive gas. Thereby, inactive gas flows powerfully downward toward the freeze drying chamber, and low temperature contamination due to such matter is further prevented.
STEWART PAUL
RENZI ERNESTO
UNIV CALIFORNIA