Thin-film liftoff assisted fabrication of amine-based PDMS TFC membrane for enhanced phenol recovery

Generally, polydimethylsiloxane (PDMS) serves as the preferred candidate for fabricating phenol separation membrane. However, PDMS membrane applications are hindered by the phenol mass transfer resistance deriving from conventional membrane preparation techniques. Here, by utilizing the thin-film liftoff (T-FLO) technique, a novel thin-film composite (TFC) membrane comprising amine-based PDMS (APDMS) nanofilm with controllable thickness was fabricated for the first time. The chemical and physical structure of the APDMS selective layer was manipulated via tuning the crosslinker composition, polymer concentration, and fabrication parameters. The TFC membrane consisting of APDMS nanofilm with thickness down to 234 nm was formed. Besides, phenol recovery performance tests were carried out at the temperature of 333.15 K, the flow rate of 70 rpm, and the feed concentration of 400 ppm. The optimized membrane had a remarkable phenol overall mass transfer coefficient (35.6 × 10−7 m/s), a high phenol recovery ratio (64.3%), excellent long-term stability, and good anti-fouling capability. The newly-developed APDMS TFC membranes have shown certain potential applications in organic acid recovery. Amine-based PDMS (APDMS) thin-film composite membranes with modified chemical composition and physical structure in selective layers were fabricated by the thin-film liftoff technique. The as-fabricated membranes showed outstanding phenol overall mass transfer coefficient, good long-term stability, and potential organic acid recovery applications. [Display omitted] •PDMS chains were functionalized with amine groups.•TFC membranes with APDMS as selective layer were fabricated via the T-FLO technique.•The chemical and physical structure of the APDMS selective layer were adjusted.•The APDMS TFC membranes had remarkable Kov of phenol.•The prepared membranes were applied in other organic acids recovery.