Diffusion Separation Methods

Abstract

Diffusion separation methods refer collectively to processes such as gaseous diffusion and gas centrifugation, developed specifically for difficult separations such as those involving the isotopes of uranium. These processes, used worldwide primarily for uranium enrichment, are based on the differences that exist in the rates of gaseous diffusion of the particular isotopes. These difficult separations almost always involve an aggregation of separation units known as a casade. Casade design, unit separative capacity, ideal and real casades, and various separation factors are presented. Equipment and plant design for the enrichment of uranium‐235 by gaseous diffusion, by various pressure diffusion processes, and by jet diffusion, also known as the separation nozzle process, is discussed.

New Design Methodology Based on Self-Heat Recuperation for Production by Azeotropic Distillation

“…However, conventional distillation is energy-consuming because ethanol and water form an azeotropic mixture, and it is believed that about half of the heat value of bioethanol is required to distill the ethanol from the mixture. To separate pure ethanol from ethanol−water mixtures by distillation, it is necessary to use an entrainer (azeotroping agent) because the azeotropic mixture is one that vaporizes without any change in composition in azeotropic points. , Benzene, cyclohexane, or isopropyl alcohol can be used as entrainers for the ethanol−water mixture. Therefore, at least two separation units are required to produce pure ethanol, leading to increased energy consumption.…”