Properties and ultrafiltration efficiency of cellulose acetate/organically modified Mt (CA/OMMt) nanocomposite membrane for humic acid removal

• The effect of OMMt on the properties and performance of CA/OMMt membrane was investigated.
• Addition of OMMt improves hydrophilicity and porosity of nanocomposite membrane.
• Mechanical and thermal stability of CA/OMMt membranes were decreased by OMMt dosage.
• At high clay dosage, membrane performance is enhanced when compared with pure CA membrane.

In this study, asymmetric nanocomposite membranes based on cellulose acetate and organically modified montmorillonite (OMMt) were prepared by a combination of solution dispersion and phase inversion methods. The effects of OMMt on the properties and performance of prepared nanocomposite membranes were investigated. The prepared nanocomposite membranes were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), contact angle, porosity measurement, tensile strength techniques, and humic acid adsorption. Pure water flux (PWF) and humic acid rejection were studied using an ultrafiltration experimental setup. The results showed that the PWF significantly increased from 3.8 × 10− 5 to 6.6 × 10− 5 m3/m2·s with increasing OMMt concentration from 0 to 5 wt.%. By increasing the OMMt concentration, rejection decreases from 94.54% for pure cellulose acetate membrane to 91.85% for 2 wt.% OMMt/CA nanocomposite membrane, while rejection of 95.05% was obtained for 5 wt.% OMMt/CA membranes.