Preparation of composite nanofiltration membrane with β-cyclodextrin as aqueous monomer and dye rejection properties

Using β-cyclodextrin (β-CD) as the aqueous phase monomer and trimesyl chloride (TMC) as the oil phase monomer, a high-throughput β-CD/TMC composite nanofiltration membrane was prepared by the interfacial polymerization method. The pore model and electrostatic repulsion-steric hindrance model were used to explore the mechanism of dye separation. Infrared spectrometer, field emission electron microscope, contact angle measuring instrument and Zeta potential analyzer were used for analysis and characterization. The results showed that the peak of ester group which is generated by IP appeared in the FT-IR. Zeta potential analysis indicated that the surface of composite NF membrane was negatively charged. SEM images structure and contact angle values showed that when the concentration of β-CD was 4.0%, a lot of folds appeared on the membrane surface and the membrane was more hydrophilic. At the pressure of 0.2 MPa, the pure water flux can reach 207.81 L•m-2•h-1, the rejection of the Congo red, the Bengal rose, the reactive brilliant red X-3B and the methylene blue was 100%, 99.05%, 97.65% and 32.92%, respectively. The 6 h operation can effectively reject the dye reactive brilliant red X-3B with rejection higher than 97% flux goes down and then keeps the tendency of stable. © All Right Reserved.