Sustainable Membrane Preparation: Approaches Using Cellulose Acetate as a Biopolymer and Ethyl Lactate as a Green Solvent

This study investigates the fabrication of porous green membranes by the phase inversion technique under sustainable conditions, using cellulose acetate (CA) as a biopolymer and ethyl lactate (EL) as a biobased and biodegradable green solvent. Two distinct phase inversion techniques, NIPS (nonsolvent-induced phase separation) and VIPS/NIPS (vaporinduced phase separation/nonsolvent-induced phase separation), have been employed, varying the polymer concentration and the presence of additives that can act as pore-formers. This study also examines the influence of key process and preparation parameters, such as the composition of the polymeric solution and the time of exposure to water vapor, on the resulting membrane morphology and properties. Finally, the newly developed membranes were fully characterized. The microporous membranes displayed good mechanical properties, with pore sizes ranging from 0.11 to 1.12 μm, with water permeability values between 1631 and 5673 L·m−2 · h−1 ·bar−1