PEDOT:PSS Nanoparticle Membranes for Organic Solvent Nanofiltration

• Published in: Small (Weinheim an der Bergstrasse, Germany) Germany), 2024-12, Vol.20 (52), p.e2405285-n/a
• Main Authors: Zhang, Jia‐Chen, Lv, Tian‐Run, Yin, Ming‐Jie, Ji, Yan‐Li, Jin, Cheng‐Gang, Chen, Bo‐Hao, An, Quan‐Fu
• Format: Article
• Language: English
• Subjects: acid treatment; Charge efficiency; Food additives; free volume; Industrial applications; interparticle distance; Membranes; Nanofiltration; Nanoparticles; organic solvent nanofiltration; PEDOT:PSS nanoparticle membrane; Polystyrene resins; Rejection; Reluctance; Separation; Solvents; Stability; Sustainable development; Vacuum filtration
• ISSN: 1613-6810; 1613-6829; 1613-6829
• DOI: 10.1002/smll.202405285

Recycling of valuable solutes and recovery of organic solvents via organic solvent nanofiltration (OSN) are important for sustainable development. However, the trade‐off between solvent permeability and solute rejection hampers the application of OSN membranes. To address this issue, the poly(3,4‐ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) nanoparticle membrane with hierarchical pores is constructed for OSN via vacuum filtration. The small pores (the free volume of the polymer chain) charge for the solute rejection (high rejection efficiency for low molecule weight solute) and allow solvent passing while the large pores (the void between two PEDOT:PSS nanoparticles) promote the solvent transport. Owing to the lack of connectivity among the large pores, the fabricated PEDOT:PSS nanoparticle membrane enhanced solvent permeance while maintaining a high solute rejection efficiency. The optimized PEDOT:PSS membrane affords a MeOH permeance of 7.2 L m−2 h−1 bar−1 with over 90% rejection of organic dyes, food additives, and photocatalysts. Moreover, the rigidity of PEDOT endows the membrane with distinctive stability under high‐pressure conditions. The membrane is used to recycle the valuable catalysts in a methanol solution for 150 h, maintaining good separation performance. Considering its high separation performance and stability, the proposed PEDOT:PSS membrane has great potential for industrial applications. The PEDOT:PSS nanoparticle membrane is fabricated via a solution processing technique, and the interparticle distance of the membrane can be tailored via acid post‐treatment. Resultantly, the PEDOT:PSS membrane afforded both high MeOH permeance and rejection efficiency. The PEDOT:PSS membrane can be stably running for 150 h in a photocatalyst methanolic solution.