MOF laminates functionalized polyamide self-cleaning membrane for advanced loose nanofiltration

Abstract

• High performance loose nanofiltration membrane was prepared by adding Zn-TCPP laminates to the interfacial polymerization of melamine and TMC. • The addition of Zn-TCPP laminates improved the permeance of membrane to 63.2 L m -2 h −1 bar −1 . • Zn-TCPP laminates enables the membrane superior dye degradation ability. Rational material design and controllable membrane preparation technology is essential to improve the separation performance and anti-fouling ability of a membrane. In this study, melamine is selected as the aqueous phase monomer of the interfacial polymerization and photocatalytic Zn-TCPP laminates are embedded into the membrane to develop a high performance self-cleaning loose TFN membrane. The melamine/TMC TFC membrane with a woven-like loose polyamide layer exhibits water permeance up to 30.1 L m -2 h −1 bar −1 and a good dye rejection (≥97%). With the addition of Zn-TCPP laminates, the membrane permeance is enhanced to 63.2 L m -2 h −1 bar −1 (TFN-2), which is twice than the TFC membrane. Furthermore, the dye rejection of TFN-2 remains high, and the rejection of salts (NaCl, Na 2 SO 4 ) is below 10%. Besides, the Zn-TCPP embedded TFN membrane can fully degrade the attached dye within 15 min under visible light, and the permeance of the treated membrane can be restored to its original state. The resultant Zn-TCPP/TFN loose nanofiltration membranes with excellent self-cleaning ability can not only provide a potential solution for the removal of organic pollutants, but also offer new inspiration for fabricating high performance self-cleaning loose nanofiltration membranes through a mature and facile interfacial polymerization method.