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Title: Raman imaging of membrane fouling
Membrane processes are widely used in industrial applications such water purification, food processing and pharmaceutical manufacturing. During their operation, the accumulation of foulants in membrane pores and on membrane surfaces lead to the reduction in flux, membrane lifetime and increase in operational cost, and the understanding of the fouling phenomenon is important for mitigating these problems. In this paper we report the application of Raman chemical imaging as a means of identify and map foulants on a membrane surface. The surface of a Polytetrafluoroethylene (PTFE) membrane was studied by Raman chemical imaging before and after fouling during desalination via membrane distillation. Information about location and concentration of three different salts namely CaSO4, BaSO4 and CaCO3 was studied. The three salts showed different distribution patterns, and their distribution was analyzed by correlation mapping and multivariate curve resolution. It was observed that CaSO4 agglomerated in specific places while the BaSO4 and CaCO3 were more distributed. Raman imaging appears to be a powerful tool for studying membrane foulants and can be effective in identifying the distribution of different species on a membrane surface.  more » « less
Award ID(s):
1822130
NSF-PAR ID:
10162371
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
Separation and purification technology
Volume:
242
ISSN:
1383-5866
Page Range / eLocation ID:
116763
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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