Membrane processes:
In contrast, membrane processes are rate governed processes wherein we talk not only of associative quantity of the substance separated but also about the rate at which the separation is taking place. In addition, membrane processes are continuous separation processes and there is no required of membrane regeneration as is required in equilibrium governed processes. Since of some of its inherent advantages, the membrane processes are replacing some of the well known separation techniques for technological applications.
The present unit is indicated to membrane separations. It starts with a simplified picture of membrane separation, familiarity along with some of the general terms and a classification of different membrane processes. The important characteristics of these processes are briefly elaborates. This is followed through a description of the different mechanisms of separation by membrane processes. The processes such as osmotic phenomena, dialysis, reverse osmosis, and electrodialysis are explained within detail. Membrane separations have multidisciplinary applications and a few of these are highlighted towards the end of the unit.
Objectives
After studying this Unit, you should be able to
- Elaborates the general aspects and importance of various membrane processes,
- Know and explain the various mechanisms involved in membrane based separations,
- Describes the terms like product flux, percent recovery, solute retention percentage, membrane fouling and concentration polarization,
- Describe osmosis, dialysis, reverse osmosis and electrodialysis processes and how they differ from each other, and
- enumerate a few of the significant applications based on membrane separations from different areas of science and technology.