Dual-functionalization of amine-ZIF-8 and sulfone-GO for improved flux, antifouling, and rejection performance of thin film composite membrane

This study focuses on developing the amine-functionalized zeolitic imidazole framework-8 (NH₂-ZIF-8) encapsulated onto sulfone-functionalized graphene oxide (SGO) to enhance the properties of the PA-TFC membrane for textile wastewater treatment. Zeolitic imidazole framework-8 (ZIF-8) and graphene oxide (GO) were both functionalized with 3-amino-1,2,4-triazole (Atz) and sulfanilic acid, respectively, to achieve NH₂-ZIF-8@SGO. The composition of NH₂-ZIF-8 was varied on SGO via the in-situ growth method to acquire the optimum formulation of the NH₂-ZIF-8@SGO composite. The optimum 0.5% formulation of NH₂-ZIF-8@SGO was embedded into the PA layer to enhance membrane performance. The results confirmed that NH₂-ZIF-8@SGO-modified TFC membranes exhibited improved water flux and fouling resistance with ∼90% water flux recovery. In addition, the TFC membranes rejected above 99% of textile wastewater primarily through size exclusion and the Donnan exclusion mechanism. These results show that NH₂-ZIF-8@SGO increases the hydrophilicity of the PA-TFC membrane and contributes to its high rejection efficiency, improved antifouling performance, and prolonged operational lifespan.