Preparation of a Novel MnOx/BC Hybrid Membrane System Functionally Integrated with Oil Absorption and Antimicrobial Activity
|關鍵字:||吸油;抗菌;antimicrobial activity;oil absorption|
The lack of the water resource and drinking water will be a potential problem due to the critical pollution and increasing population. In recent years, many scientists are devoted into the study of water purification for removal of water pollutions, such as the occurrence of oil spillage on water surface, the organic compounds and heavy metal ions in water. In this thesis, we successfully fabricate a composite membrane integrated with oil absorption ability and antibacterial property. We found, a cryptomelane-type manganese oxide (K-OMS-2) whose particular octahedral sieve structure has large surface area was used as an oil absorption material. The K-OMS-2 would be mixed with bacterial cellulose (BC) substrate and thereby form a hybrid membrane system; antimicrobial activity, then, could be achieved by the reduction of silver nanoparticles (AgNPs) on the substrate surface. First, the K-OMS-2 synthesized by hydrothermal method and reflux method was compared in their basic characteristics by SEM, EDS, TEM and SAED; the surface area and pore-size distribution were investigated by BET and BJH analysis. Next, we employ the BC that was produced by incubation of Gluconobacter xylinum bacteria in a static culture for several days as a strong substrate for composition. After hybrid with K-OMS-2, the contact angles of oil/water on the surface and oil absorption ability were measured. Hydrophilic and oleophilic performances were displayed at the same time, but PDMS coating can modulate water adhesion phenomenon from hydrophilicity into hydrophobicity. Also, the hybrid membrane has thermal stability from TGA test. Finally, good antimicrobial activity was exhibited by the reduction of AgNPs on the membrane surface. The results were proved to be effective on inhibition for the growth of both Methicillin-resistant Staphylococcus aureus (MRSA) (Gram-positive bacteria) and Acinetobacter baumannii (AB) (Gram-negative bacteria) for 24 hours. Due to the good oil absorption and effective antibacterial property, this novel composite membrane has the potential for applications of wastewater treatment.