Ding Lin, Han Deyi, Zhang Haichuan, Yang Shujuan, Zhang Yong
State Key Laboratory of Bio-based Fiber Materials, College of Textile Science and Engineering, Zhejiang Sci-Tech University, Hangzhou 310018, China.
Department of Engineering, Hangzhou Normal University, Hangzhou 311121, PR China.
Int J Biol Macromol. 2025 May;308(Pt 4):142482. doi: 10.1016/j.ijbiomac.2025.142482. Epub 2025 Mar 30.
This study presents the development of advanced tight polyethersulfone (PES) ultrafiltration membranes enhanced with polydopamine-coated carboxylated cellulose nanocrystrals (PDA@C-CNC) as functional fillers. The PDA@C-CNC fillers were synthesized via an in situ self-polymerization approach and employed as surface segregation agents during membrane preparation. Utilizing the non-solvent-induced phase separation (NIPS) technique, the highly hydrophilic PDA@C-CNC particles migrated to the interface between the polymer solution and the coagulation bath and tightly adhered to the polyethersulfone (PES) matrix through strong hydrogen bonding and π-π interactions, forming a dense, hydrophilic selective surface layer rich in polar functional groups (amino group (-NH) and hydroxyl group(-OH)). Concurrently, the support layer developed a porous structure characterized by extended and widened cavities, facilitating enhanced mass transfer. The synergistic combination of a selective dense surface layer and an optimally structured support layer endowed the modified membranes with remarkable permeability and selectivity. Surprisingly, the water flux of the modified membrane with 0.2 % PDA@C-CNC (MPC0.2) achieved a remarkable 332 L·m·h·bar, which is 2.29 times higher than that of the unmodified membrane (M0). Additionally, MPC0.2 demonstrated exceptional dyes rejection rates (Congo red (CR) > 99.7 %, Eriochrome Black T (EBT) > 97.7 %) alongside minimal salt rejection (sodium chloride (NaCl): 0.2 %, sodium sulfate (NaSO): 1.7 %). These findings highlight the potential of PDA@C-CNC/PES composite membranes for efficient and selective removal of dyes and salts from textile wastewater.
本研究展示了一种先进的紧密聚醚砜（PES）超滤膜的开发，该膜通过聚多巴胺包覆的羧化纤维素纳米晶体（PDA@C-CNC）作为功能填料进行增强。PDA@C-CNC填料通过原位自聚合方法合成，并在膜制备过程中用作表面偏析剂。利用非溶剂诱导相分离（NIPS）技术，高度亲水的PDA@C-CNC颗粒迁移到聚合物溶液与凝固浴之间的界面，并通过强氢键和π-π相互作用紧密粘附在聚醚砜（PES）基质上，形成富含极性官能团（氨基（-NH）和羟基（-OH））的致密、亲水选择性表面层。同时，支撑层形成了具有扩展和加宽空洞特征的多孔结构，促进了传质增强。选择性致密表面层和结构优化的支撑层的协同组合赋予了改性膜显著的渗透性和选择性。令人惊讶的是，含0.2% PDA@C-CNC的改性膜（MPC0.2）的水通量达到了332 L·m⁻²·h⁻¹·bar，比未改性膜（M0）高2.29倍。此外，MPC0.2表现出优异的染料截留率（刚果红（CR）>99.7%，铬黑T（EBT）>97.7%），同时盐截留率极低（氯化钠（NaCl）：0.2%，硫酸钠（Na₂SO₄）：1.7%）。这些发现突出了PDA@C-CNC/PES复合膜在从纺织废水中高效选择性去除染料和盐方面的潜力。
