Adsorptive removal of 2,4-DCP from water by fresh or regenerated chitosan/ACF/TiO2 membrane

In order to remove micro-pollutant 2,4-DCP (dichlorophenol, 1-50 mg/L) from aqueous solution using low pressure membrane separation process, and to study photocatalytic/oxidative cleaning of membrane fouled by adsorption, a new organic/inorganic hybrid composite membrane with adsorption, filtration and photocatalysis property was studied which contains coated chitosan (CS), activated carbon fiber (ACF) adsorbent and titanium dioxide on terylene fabrics. The scanning electron microscopy (SEM) of the membrane showed TiO2 as the top layer, while CS and ACF were under TiO2. FTIR spectrum analysis reflected the feature of CS, ACF and TiO2, and water flux measurements indicated that the composite membrane with coating layer still possessed high filtration property. The adsorptive removal of 2,4-DCP using both static and dynamic modes (25-100 L m(-2) h(-1)) was highly efficient. The CS/ACF/TiO2 membrane adsorption capacity can be regenerated by oxidizing adsorbed 2,4-DCP via in situ or off-site photocatalysis and/or Fenton oxidation, and both off-site oxidation methods are more efficient than in situ oxidation. (C) 2009 Elsevier B.V. All rights reserved.