Membrane Formation Experiment

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Membrane Formation Experiment
Scanning Electron Microscope image of a cellulose acetate (CA) based membrane for water filtration.

The goal of this experiment is the production of cellulose acetate (CA) based membrane for water filtration. The production stages of this membrane are similar to those of the commercially available DrinkPure™ water filter, but the production of the membrane specified herein has been simplified to be feasible with daily commodities such as a kitchen blender, mirror glass plates, scotch tape and stainless steel rulers.


The filtration effectiveness of the membrane is tested in a second step. The membrane successfully rejects dispersed watercolors, whereas dissolved colors such as food coloring freely pass the membrane. Alternatively, one can also filter water from a pond or stream and show the effectiveness of the membrane by means of LB agar plates for bacteria. Such a project would be suitable for a collaboration with a biology department. 

Experiment elaborated by Adrian Kaiser and Robert Grass

Student handout (PDF, 330 KB)

Instructor notes (PDF, 3.9 MB)

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