화학공학소재연구정보센터
Desalination, Vol.365, 1-7, 2015
A method to characterize the compressibility and stability of microfiltration membrane
In this study, the membrane compaction of polysulfone (PS), poly(ether sulfone) (PES) and poly(vinylidene fluoride) (PVDF) flat sheet membranes with finger-like porous structure during pressure-driven filtration process was investigated. The parameters of membrane compression index (s(c)), membrane rebound index (s(r)) and membrane base resistance (R-T0) were proposed to explore the microfiltration membrane compressibility and its effects to performance degradation. The results revealed that the PS, PES and PVDF membranes all showed the maximum compression index and low rebound index in the initial pressure-driven filtration process. (s(c) - s(r)) decreased after three supercharging-decompression filtration cycles. s(c) and s(r) tended to be equal and stabilized at 0.41 +/- 0.06, 0.35 +/- 0.06 and 0.25 +/- 0.04 for the PVDF, PES and PS membranes respectively. It unveiled a reduction of the residual deformation and the stability of the membrane structure. The elastic deformation exerted a more important effect on the flux of PVDF membrane than that of PES and PS membrane. The study also indicated that the compression deformation resulted in smaller pore size and larger membrane base resistance after continuing pressure-driven filtration process, which lead to the decay of membrane flux. (C) 2015 Elsevier B.V. All rights reserved.