Abstract:

Nowadays, membrane bioreactors (MBR) are the common method used to treat wastewater. In this study, a high-flux, high-strength graphene oxide (GO)-doped braided tube reinforced polyvinylidene fluoride (PVDF) hollow fiber membrane was prepared by green diluent thermal induced phase separation (TIPS) method and fiber reinforcement technology. The surface of GO had the function of abundant oxygen, which can significantly improve the permeability flux and hydrophilicity (anti-fouling) of PVDF hollow fiber membranes. The results showed that the tensile strength of the hollow fiber membrane can reach 223.75MPa, and the water contact angle of the reinforced PVDF hollow fiber membrane decreased from 102.04° to 89.71°, and the pure water flux increased from 920.74L/(m²·h) to 1417.45L/(m²·h) with the increase content of GO. Finally, the experimental test of membrane activated sludge filtration with MBR test equipment indicated that the rejection was greater than 99.50% and the stable rejection was greater than 98%. Consequently, the prepared PVDF hollow fiber membrane by the whole process of green preparation exhibited a good guiding role in replacing the secondary polluted hollow fiber membrane in the current market.

Key words: polyvinylidene fluoride (PVDF), graphene oxide (GO), hollow fiber membrane, TIPS-fiber reinforcement technology, green diluent

摘要：

目前，膜生物反应器（MBR）用中空纤维膜量大，制备过程中使用溶剂易造成二次污染，本文采用绿色稀释剂热致相分离（TIPS）法与纤维增强联用技术制备了大通量、高强度氧化石墨烯（GO）掺杂编织管增强型聚偏氟乙烯（PVDF）中空纤维膜。GO表面具有含丰富氧官能团可明显改善PVDF中空纤维膜渗透通量与亲水性（抗污染性）。结果表明：纤维增强技术可使中空纤维膜断裂强度223.75MPa，随GO含量增加，增强型PVDF中空纤维膜水接触角值从102.04°降低至89.71°，纯水通量从920.74L/(m²·h)增至1417.45L/(m²·h)。经实验用MBR小试装备测试膜活性污泥过滤表明，其截留率大于99.50%，稳定运行后截留率仍大于98%。因此，本文全流程绿色制备的增强型PVDF中空纤维膜对替代目前市场二次污染中空纤维膜可提供科学依据与技术支撑。

关键词: 聚偏氟乙烯, 氧化石墨烯, 中空纤维膜, 热致相分离法与纤维增强联用技术, 绿色稀释剂