Pervaporative transport of aqueous ethanol: Dependence of permeation rates on ethanol concentration and permeate side pressures

✍ Scribed by M. Tsuyumoto; K. Akita; A. Teramoto

• Publisher: Elsevier Science
• Year: 1995
• Tongue: English
• Weight: 1012 KB
• Volume: 103
• Category: Article
• ISSN: 0011-9164
• DOI: 10.1016/0011-9164(95)00074-7

✦ Synopsis

The pervaporative transport of aqueous solutions of high ethanol content was studied on polyion complex membranes. It was found that the permeation rate of water became smaller with the decrease in the water content of the feed solution and/or with the increase in the permeate side pressure. This fact suggested that the permeation rate was dependent on the activity of water in the membrane. Therefore, on the basis of the solution-diffusion theory, an equation of the permeation rate of water was derived on the assumption that both the activity and the diffusion constant of water depended on concentration. The permeation rate was calculated for the membranes of different thickness and under various permeate side pressures. It was confirmed that the derived equation accurately described the experimental data for permeation rate of water. On the other hand, the permeation of ethanol resulted mostly from the volume flow through incomplete parts of the membrane but was negligible compared with the permeating water flow.