Facilely prepare ultra-high molecular weight polypropylene loose nanofiltration membrane for efficient dye/salt separation

Abstract

The simple strategies and processes for preparing nanofiltration (NF) membranes with well-pore channels and high separation efficiency have received growing attention in academia. Herein, ultra-high molecular weight polypropylene (UHMWPP) has been successfully fabricated into high-performance loose NF membranes through thermally induced phase separation (TIPS). The results showed that the as-prepared UHMWPP loose NF membrane has a good water permeance (17.7 L m−2 h−1 bar−1), a high RB rejection (99 %), and a low inorganic salt retention rate (NaCl: 1.9 %), which makes the loose NF membrane a potential choice for dye/salt separation. In addition, the membrane also has good antifouling properties, acid and alkaline resistance, and long-term stability. Thus, this work offers a viable and pragmatic technical approach for addressing high-salt printing and dyeing wastewater, with broad prospects for application and practical value.