Internal connectivity of pores

Internal connectivity of membrane pores a potentially a factor affecting flux. All the membranes commonly used in MBR have a highly interconnected pore structure, where the water that already passed the pore entrance has multiple channels to go through until it completely passes to the permeate side of the membrane. If one channel is plugged by particles or macromolecules, the water can still pass through alternative channels. This is an important mechanism to mitigate flux loss from internal pore blocking (Ho, 2006).

It has suggested that track-etched membranes are lack of internal connectivity, thereby vulnerable to internal pore blocking. They are made by the bombardment of fission fragments on polymer film to make narrow tracks in the film followed by etching the tracks with chemicals, thereby pore size distribution is very narrow, but no internal connectivity exists in pore structure.

Fig. 1 and Fig. 2 shows surface structures of various membranes (Ho, 2006).

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Fig. 1. Scanning electron micrographs of the surface of a) PVDF, b)CA, c)MCE, and d)PTFE membranes.

 

Fig. 2. Scanning electron micrographs of the surface of 1)PCTE, and b)Anopore Al2O3 membrane

Fig. 2. Scanning electron micrographs of the surface of 1)PCTE, and b)Anopore Al2O3 membrane

 

© Seong Hoon Yoon