Preparation of cellulose triacetate/cellulose acetate (CTA/CA)-based membranes for forward osmosis

► The first study of CTA/CA mixtures for FO membrane via immersion precipitation. ► High water flux and salt rejection were obtained by optimizing the fabrication. ► Computerized image processing was useful for assessing the membrane substrates. ► Open space ratios of the support determined the membranes' water fluxes.