Activated-Carbon-Doped Non-Solvent-Induced Phase-Inversion Membranes: A Comprehensive Study on Synthesis, Characterisation, and Performance Evaluation

Abstract

Wastewater treatment often enables discharge into natural water bodies, but for effective reuse, further treatment is essential. Membrane processes provide a precise solution yet face limitations due to fouling and organic material adsorption, impacting their performance. This study focuses on synthesising ultrafiltration membranes using non-solvent-induced phase separation. These membranes are produced from a Polyethersulfone/N,N′-dimethylacetanamide (PES/DMA) solution with varying concentrations of three commercial powdered activated carbons (ACs). The membranes undergo comprehensive analysis, revealing different behaviours based on AC type and concentration in the active layer. Among the membranes, Norit R with 0.5 wt.% concentration exhibits the highest polyethylene glycol (PEG) rejection, with an impressive rejection index (R) of 80.34% and permeability coefficient of 219.29 (L·m−2·h−1·bar−1). AC-enhanced membranes display superior selectivity compared to non-doped PES membranes. This work highlights the significant influence of AC textural properties, specifically specific surface area, total micropore volume, and average micropore width, on membrane performance, particularly the rejection index.