Surfactant pretreatment of a polysulfone ultrafilter for reduction of antifoam fouling.
Effectiveness of surfactant precoat treatment of the polysulfone ultrafilter was first investigated for reduction of membrane fouling in ultrafiltration of antifoam. Fifteen different surfactants, including alcohols and synthetic nonionic surfactants, were tested. In general, pretreatment with nonionic surfactant gave a larger flux than that with alcohol did. The flux increase by pretreatment with nonionic surfactant depended on a hydrophile lipophile balance (HLB) value and type of hydrophobic tail. The most effective surfactant for reducing antifoam fouling among the 15 surfactants was Brij-58 which has an HLB value of 16 and a straight alkyl hydrophobic chain. The ultrafiltration flux of the membrane treated with Brij-58 was almost three times larger than that of untreated membrane. The precoat treatment with Brij-58 was the most effective for reducing antifoam fouling in terms of rejection properties.Furthermore, flux was also improved by the surfactant pretreatment in ultrafiltration of model process streams, such as fermentation media, broth, and yeast suspension with or without antifoam. The surfactant Brij-58 was found to be more effective for reducing membrane fouling in ultrafiltration of model stream YG compared with ethanol or Brij-35. The mean flux increase by the pretreatment with Brij-58 was about 80% in ultrafiltration of the model stream without antifoam. When antifoam was added to the model stream, flux was almost doubled by the pretreatment with Brij-58. The effectiveness of surfactant precoat treatment for reducing membrane fouling was also confirmed in terms of rejection properties. (c) 1994 John Wiley & Sons, Inc.
Yamagiwa
K
K
Department of Material and Chemical Engineering, Niigata University, 2-8050 Ikarashi, Niigata 950-21, Japan.
Kobayashi
H
H
Onodera
M
M
Ohkawa
A
A
Kamiyama
Y
Y
Tasaka
K
K