Polyethersulfone (PES)/Cellulose Acetate Butyrate (CAB) Hybrid Hollow Fiber Membranes for Organic Matter Removal from Produced Water

摘要

In the United States, for every barrel of oil, approximately seven barrels of water are produced. Produced water consists of various amounts of organic and inorganic constituents from the source geologic formation and associated hydrocarbons. Produced water handling has become a major effort of all waterflood operations. Membrane technology has been widely used for produced water purification due to its economic and portable properties. However, the presence of organic matter in produced water causes serious membrane fouling, which shortens membrane life and increases operation costs. In this study, to reduce organic components in produced water, we fabricated a series of polyethersulfone (PES)/cellulose acetate butyrate (CAB) hybrid hollow fiber membranes (HFMs) for the removal of organic matters (benzene, toluene, octanoic acid and hexanoic acid) from produced water. The morphology of the hybrid PES/CAB hollow fiber membranes was characterized by scanning electron microscope (SEM) and atomic force microscope (AFM). The performance of the hybrid PES/CAB hollow fiber membranes was evaluated in terms of pure water flux, organic matter separation efficiency, flux decline ratio and flux recovery ratio. The results of our study reveal that the PES/CAB hybrid hollow fiber membranes showed an open-ended selective layer with homogenous CAB distribution. Compared to the pure PES hollow fiber membrane, the hybrid hollow fiber membranes improved the pure water flux by 20.3%. Separation tests showed that the hybrid PES/CAB hollow fiber membranes exhibited high separation efficiency of up to 99.8%. With 1.74 wt. % of CAB presented in the PES dope solution, the hybrid PES/CAB hollow fiber membranes possessed the lowest flux decline ratio and highest flux recovery ratio, indicating the excellent antifouling ability of the PES/CAB hollow fiber membranes. Based on these results, the PES/CAB hybrid hollow fiber membranes could serve as an attractive alternative for removing organic matter from produced water.