Effect of powdered activated carbon deposited ultrafiltration membrane for enhanced micro-polluted water treatment

Abstract

Aiming at the current situation that ultrafiltration membrane is inefficient to remove the dissolved organic matters (DOM) in raw water and will meet serious membrane fouling after long-term operation, powdered activated carbon (PAC) was used as the coating material to form a cake layer on the surface of 100 kDa Polyvinylidene fluoride (PVDF) ultrafiltration membrane. In order to study its capability of removing macromolecular organic matters, particles and bacteria in micro-polluted water and the corresponding mechanism, contact angle (CA), fourier transform infrared spectrometer (FTIR) and scanning electron microscope (SEM) were systematically investigated to analyze the hydrophobicity, composition of the biofilm formed and morphology on the membrane surface. Results showed that the dynamic membrane can significantly improve the removal of organic matters through the adsorption of the powdered activated carbon. The removal rates of dissolved organic carbon (DOC), UV254 and proteinaceous substance are respectively 91.5%, 94.4% and 91.1%. Compared with the control PVDF ultrafiltration membrane, the dynamic membrane has better hydrophilicity. The loose cake layer formed by powdered activated carbon can also avoid the direct interaction between DOM and UF membrane, which slowed down the membrane fouling development.

Keywords

• micro-polluted water
• ultrafiltration
• powdered activated carbon
• membrane flux
• membrane fouling