Construction of PES composite ultrafiltration membrane with high permeability and selectivity assisted by three-dimensional Ni-Zn MOF@Multi CNC

In this work, the novel metal organic frameworks/multi-branched nanocellulose (Ni-Zn MOF@Multi CNC) fillers with different three-dimensional nanostructures are fabricated via two in-situ growing strategies, which were blended into Polyether sulfone (PES) matrix to construct composite ultrafiltration (UF) membranes. Furthermore, the effects of two structures of fillers on construction and performance of composite membranes are detailed investigated here. The results confirmed that the obtained PES composite membranes exhibited excellent permeability and selectivity because of the ultra-high hydrophilicity, abundant pores, and more negative charge of Ni-Zn MOF@Multi CNC fillers. Besides, compared with nanosphere structure of Ni-Zn MOF@Multi CNC, the nanoflower filler could provide more pores and cavities to enable higher water permeance, and more active surface charge (more -COO- groups) to increase protein rejection. The Ni-Zn MOF@Multi CNC 0.05 /PES membrane showed an 83 % higher permeance (up to 1151.00 L/m 2 h) and greatly improved BSA rejection (99 %). The Ni-Zn MOF@Multi CNC 0.05 /PES membrane has been successfully applied to different wastewater treatment, and shows expectant ultrafiltration performance.