Preparation and performance study of PTh/PVDF composite separation membrane: Fabrication of nanoscale selective layer using readily available thiophene

The development of high-performance microporous polymer composite separation membranes using simple and readily available monomers is a critical focus. In this study, thiophene, an aromatic compound commonly occurring in petroleum, has been employed in the fabrication of high performance PTh/PVDF composite separation membrane. The entire membrane formation process was conducted under a vapor phase environment, eliminating the need for additional solvents, which offers advantages such as simple operation, high membrane-forming efficiency and environmental friendliness. The selective performance of PTh/PVDF membrane was highly satisfactory, exhibiting rejection rates of 97.78 % for neutral red (NR), 96.34 % for azure II (Azu II), and 98.74 % for Congo red (CR). The permeability for various dye solutions ranged from 20 to 40 L m⁻²·h⁻¹·bar⁻¹, indicating excellent filtration efficiency for practical applications. Furthermore, PTh/PVDF membrane demonstrated remarkable resistance to harsh conditions, maintaining outstanding separation efficiency under conditions of high alkalinity, elevated temperatures, and saline contamination. Additionally, PTh/PVDF membrane showed promising stability, with a rejection rate for NR molecules consistently above 97.34 % over a continuous filtration test lasting 48 h. The readily available raw material and simplicity of the preparation process position the high-performance PTh/PVDF membrane as a promising candidate for applications in wastewater treatment.